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GM Crops & Food: Biotechnology in Agriculture and the Food Chain Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/kgmc20
Surveys suck a
Douglas A Powell a
Powell Food Safety; Brisbane, Australia Published online: 12 Nov 2013.
To cite this article: Douglas A Powell (2013) Surveys suck, GM Crops & Food: Biotechnology in Agriculture and the Food Chain, 4:3, 195-201, DOI: 10.4161/gmcr.26777 To link to this article: http://dx.doi.org/10.4161/gmcr.26777
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Special Issue: Consumer Affairs
Special Issue: Consumer Affairs
GM Crops and Food: Biotechnology in Agriculture and the Food Chain 4:3, 195–201; July–December 2013; © 2013 Landes Bioscience
Surveys suck
Consumer preferences when purchasing genetically engineered foods Douglas A Powell
Keywords: genetically modified, GM food, consumer behavior, theory of planned behavior
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Abbreviations: GE, genetic engineering; GM, genetically modified; GMO, genetically modified organism; PBC, perceived behavioral control; TPB, Theory of Planned Behavior
Many studies have attempted to gauge consumers’ acceptance of genetically engineered or modified (GM) foods. Surveys, asking people about attitudes and intentions, are easy-to-collect proxies of consumer behavior. However, participants tend to respond as citizens of society, not discrete individuals, thereby inaccurately portraying their potential behavior. The Theory of Planned Behavior improved the accuracy of self-reported information, but its limited capacity to account for intention variance has been attributed to the hypothetical scenarios to which survey participants must respond. Valuation methods, asking how much consumers may be willing to pay or accept for GM foods, have revealed that consumers are usually willing to accept them at some price, or in some cases willing to pay a premium. Ultimately, it’s consumers’ actual—not intended—behavior that is of most interest to policy makers and business decision-makers. Real choice experiments offer the best avenue for revealing consumers’ food choices in normal life.
Introduction Mark Lynas has strong opinions about genetic engineering (GE). By his own admission, the British author and environmental activist was a dedicated campaigner against GE in the 1990s, helping to destroy test fields of genetically modified (GM) crops, pronouncing the risks of GE in television and radio interviews, and penning numerous articles on “the evils of Genetically Modified Organisms [GMOs]” (see also http://www.guardian. co.uk/environment/2013/mar/09/mark-lynas-truth-treacherygm). In January 2013, he caused substantial media and Internet buzz by delivering a lecture to the Oxford Farming Conference in which he apologized for his years of anti-GE actions and announced his support of GM as a means to decrease the impact of agricultural production on the environment and combat nutritional deficiencies in impoverished populations around the world.1-3 Although high-profile public proclamations about Correspondence to: Douglas A Powell; Email: [email protected] Submitted: 06/17/2013; Revised: 09/17/2013; Accepted: 10/10/2013 http://dx.doi.org/10.4161/gmcr.26777
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GMOs are not uncommon from many sides of the debate, how influential on, or reflective of, the broader sentiment such public proclamations may be is fodder for psychological and social influence researchers. How the consuming public actually behaves relative to their own attitudes and convictions—or those of the prevailing public—are of particular interest to behavioral scientists, public policymakers and business marketers. How to predict a consumer’s future behavior based on current measurements of intentions or actions is the holy grail of social science research. This paper offers a review of methodologies for assessing consumer behavior as they relate to GM foods, and demonstrates how inappropriate assessment can lead to erroneous conclusions about the public’s acceptance of GM foods and restrict consumers’ choices.
Attitudes, Intentions, and Planned Behaviors Surveys are a well-established method through which to measure public opinions and attitudes. Asking people about their intentions serves as easy-to-collect proxies of behavior.4,5 The designs and administrators of surveys vary widely, ranging from in-depth studies by academic researchers and government agencies to up-to-the-minute polling by media organizations.6 The selection of respondents who are representative of a larger population allows the results to be extrapolated to this larger group. The Eurobarometer is one example of this methodology by which data on a population’s perceptions has been gathered in the European Union’s member states since 1973.7 Public opinion on biotechnology, including genetic modification, is measured through a special Eurobarometer; the 2010 survey was the seventh in the series since 1991.8 In 2010, 84% of Europeans across 27 member states had heard of GM food; of those aware of GM food, 70% agreed that it is fundamentally unnatural, and 61% disagreed with the statement that the development of GM food should be encouraged. Survey results indicated that, overall, Europeans did not see the benefits of genetically modified food and considered them unsafe or harmful. These findings were consistent with previous issues of the Eurobarometer on biotechnology in which survey respondents in most European countries were generally opposed to agricultural biotechnologies and GM food.9 According to the sixth issue, published in 2006, Europeans and Canadians hold similar negative
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also possible that asking questions will reduce the strength of the relationship between intention and behavior if it does not align with perceived social norms.20 However, adjustment mechanisms can be employed to mitigate the impacts of such measurementreactivity effects on behavior models.4 Despite the strong relationship between attitudes and behaviors, it is widely recognized that the two do not directly correspond. The Theory of Planned Behavior (TPB) is one of the most frequently used frameworks to link attitudes with behavior and allows compensation for other factors beyond attitude that contribute to behavior. TPB is based on the premise that behavior results from intentions that are derived from attitudes toward the behavior, subjective norms and perceived behavioral control (PBC).22 However, behavioral achievement depends jointly on intention and PBC (Fig. 1).13,23 The three determinants of intention are conceptually independent: • attitude toward the behavior refers to whether a person has a favorable or unfavorable attitude toward or appraisal of the behavior in question; • subjective norm is the perceived social pressure for or against carrying out the behavior; and • perceived behavioral control (PBC) is the sense of ease or difficulty of performing the behavior, and reflects past experiences as well as impediments and obstacles.23 Under the TPB model, an individual’s intention to perform a behavior is strengthened by a more favorable attitude, agreement with social norms, and greater PBC.23 The model is often adjusted by including additional components, for example moral norms (i.e., personal norms of right vs. wrong), self-identity concepts (i.e., personal or social identity) or affective influences such as emotional involvement.13 Sparks et al.24 assessed attitudes toward genetic modification based on the TPB, with perceived ethical obligation as an additional determinant of intention. A questionnaire was mailed to 2,000 randomly selected individuals in the United Kingdom; the response rate was 17%. Attitude was found to be the most strongly related of the model components to both the intention to eat GM food and the intention to support food production using gene technology; greater perceived ethical obligation to avoid GM foods was associated with lower expectations of eating GM foods. In a similar study, Cook et al.25 developed a postal survey to measure the intentions of residents of Canterbury, New Zealand to purchase GM foods based on the TPB model with self-identity as an additional determinant of intention. The model included a number of factors that the researchers hypothesized would have negative relationships with an individual’s intention to purchase GM foods, such as concern for the environment and one’s personal health, and intention to purchase organic foods. Although the response rate was low (22.4% of 1,200 surveys distributed), 60% of respondents had negative intentions toward purchasing GM foods while 10% of respondents had positive intentions. Attitude had the greatest influence on intention. Selfidentity, subjective norm and perceived behavioral control also significantly influenced intention. Respondents with concerns
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views on GM foods, while people in the US view them as more beneficial and less risky. These results are in agreement with other surveys that have been conducted in Europe, Canada and the US (for examples see refs. 10–12). When asked if they would consider purchasing food under a certain conditions, more than half of the Eurobarometer respondents would consider buying GM food if it was healthier or contained less pesticide residues than other foods and 49% might be persuaded if GM foods were more environmentally friendly; however, approval by relevant health authorities and better prices reportedly would have caused only 44% and 36% respectively to consider purchasing GM foods. One difficulty with surveys is that respondents are asked to form opinions and make choices about hypothetical scenarios. In this artificial environment, respondents may become susceptive to social desirability effects and demand characteristics, giving false answers to meet perceived expectations or avoid violating social norms.6,13 Self-report methods may be impacted by other method biases as well, such as common method variance, consistency motif and implicit theories, that may lead to inflated or deflated associations between stated responses and behavior and associated inferences.13,14 Cognitive biases may further obfuscate the relationship between survey responses and actual behavior.6 How questions are framed, the order in which they are presented and the contextual information provided may also influence how a respondent answers survey questions.6,15 Moreover, some consumers may have not had an intention about a specific behavior prior to being surveyed and may have formed the intention only when asked about it.16 This issue was highlighted in a multicountry study examining the intention of European consumers to buy GM food products, in which the researchers noted that the topic may have been of little interest to survey respondents until brought to their attention, and that respondents determined how to respond based on the framing of the question rather than through an established intention.17 In addition, Noussair et al.18 suggested that survey participants respond as citizens of society rather than as discrete individuals, providing judgments that are more reflective of their perceived role in a broader group rather than as a private consumer. In the citizen role, respondents may be more inclined to support their image of a good society, as opposed to private consumer role with the focus on self-interests and personal wants.19 Paradoxically, asking someone about their intentions to perform a future action may cause that person to change their behavior through a phenomenon known as self-generated validity or the question-behavior effect.4,20 In a study by Spangenberg,21 health club members who were asked to predict their use of the club facilities were found to increase their frequency of use for up to six months following the survey when compared with the non-surveyed control group. Chandon et al.4 cautioned that by measuring intentions through surveys, respondents form judgments that they might not otherwise form or might not access in their memory, and put more emphasis on intentions compared with other decision inputs such as tastes, mood and competitive products. Self-generated validity strengthens the association between intention and behavior, consequently leading to an overstatement of the predictive accuracy of the intention.4 It is
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about herbicide use in food production or food additives tended to not hold positive attitudes toward GM food purchase. Using their extension of the TPB model with the self-identity incorporated, the researchers determined that 166 of the responses (63.1%) were correctly predicted. Despite careful adjustments, a reasonably good fit of the TPB will only achieve correlation coefficients among the model’s constructs of about 0.60.26 Although the TPB model has provided substantial advancement in linking intentions to behavior, it is unlikely that the complexity of a consumer’s motivations and behavior can be fully determined through the simple mechanism of questioning intentions. Figure 1. Theory of Planned Behavior, adapted from Ajzen. 23 There are arguments in the published literature in support of moving away from the selfreported approach employed by surveys toward methods that measure actual purchasing behavior through equivalent gain behavioral lottery task in which varying monexperiments that offer varying prices and information that a etary options were offered as alternatives to a box of GM chococonsumer may encounter in a true marketplace (for examples lates or non-GM chocolates. The survey also queried participants see refs. 27–29). Köster30 argued that the TPB model, in which directly on the TPB constructs, such as: “How much control do actions are provoked by rational, conscious intentions, cannot be you feel you have over eating a GM free diet?” Research results adequately applied to frequent human behaviors such as eating, showed that the standard TPB model with only the original drinking and food choices, as they occur with little conscious determinants (Fig. 1) accounted for about 51% of the variance in control. Consequently, indirect methods of analysis that allow intentions, while including the additional determinants of selfthe study of natural, complex behavior in its totality, such as identity, moral norms and emotional involvement increased the situational analysis and observational methods, may be better amount of variance for which the model accounted to 66%. In suited to assessing the interactive integration of determinants of general, the participants’ attitudes toward GM foods were relatively neutral, in line with results of Eurobarometer studies in behavior.30 the British population. However, behavior was determined to Estimated Valuation Methods be much more positive than attitudes indicated: most participants were prepared to accept GM chocolates over some amount Noussair et al.18 questioned whether surveys can reflect actual of money. This was attributed to the format of the elicitation, purchase behavior when an individual’s decisions in a hypotheti- wherein the participant made a private decision rather than a cal situation may differ from a real commitment to purchase. For decision as a public citizen, and that the choice was real (parexample, most surveys do not ask respondents about what their ticipants received the options they chose, to encourage truthful purchase decisions would be at specific prices nor do they include responding) rather than hypothetical.13 subtle contextual influences that may influence an individual’s In a different valuation approach, Noussair et al.18 created an purchasing decisions. auction-like shopping environment to assess French consumers’ However, contingent valuation is a survey-based economic willingness to pay for similar types of biscuits that differed mainly technique that is used to probe respondents’ actual purchase deci- in their labeled content of GMOs. Participants were required to sions by asking how much they would be willing to pay or accept bid for real consumer goods, using money to denote their preferfor a particular good. Spence and Townsend13 used contingent ences – a mechanism that, in principle, permits true valuation to valuation to extend the TPB to examine consumers’ propensity be revealed rather than one that is inferred. The bid submitted to purchase non-GM vs. GM chocolates. Although the scenario in the auction was also used to weight the importance of the bisemployed was fictitious, since chocolates containing GM ingre- cuit characteristics to the participants, including taste, appeardients would not have been commercially available to the British ance and price, along with the GMO content. Thirty-five percent community involved in the study, requiring survey respondents of the participants were unwilling to purchase products labeled to assign monetary values to their choices provided a more real- as containing GMOs, while 23% were indifferent or valued the istic representation of consumers’ purchasing behavior in a retail presence of GMOs and 42% were willing to purchase foods with environment than the constructs of the TPB (i.e., intention and GMOs if they were sufficiently inexpensive. Participants were PBC) on their own. Recruitment of participants was topic-blind also influenced by brand names of the products; when brand in order to avoid self-selection of individuals with particular names were revealed, average bids increased for three of the four interest in GM food issues. Participants were provided with an products. Of note was the difference between these experimental
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were willing to pay premiums of 19.5% and 38% respectively for it over non-GM rice.34,35 However, Depositario et al.36 determined that the tone of information (e.g., positive, negative or two-sided) provided to participants in a valuation study with Philippine consumers substantially affected their willingness to pay a premium for Golden Rice vs. non-GM rice. With regulatory approval for commercial production and sale of Golden Rice by the Philippine government anticipated as early as 2014,37 whether consumer behavior related to GM rice estimated through valuation studies truly reflects real market behavior may soon be elucidated.
Real Choice Experiments Paasovaara and Luomala 28 described consumers’ food choices as complex processes influenced by an array of individual and environmental factors ranging from demographics and personality traits to social interactions and sensory attributes. They argued that the most reliable results will be achieved if choices are made in a real purchasing context rather than on paper or in scenarios where alternative product choices are not available. Powell et al.12 explored consumers’ purchasing behavior of GM vs. non-GM foods in an established farm market in Hillsburgh, Ontario Canada during the 2000 growing season. Both GM and non-GM corn varieties were grown at the farm where the market was located. Shoppers were presented with GM sweet corn sideby-side with conventionally-grown sweet corn, with signage on each bin outlining the differences between the two commodities, including the production practices required for each. Endof-season tallies determined that shoppers purchased about 50% more of the GM sweet corn compared with the conventional sweet corn. A limited number of intercept interviews were conducted with market shoppers who indicated that pesticide use— required more frequently on the conventional corn—was more of a concern than GE, but that taste and quality had the most influence on their purchasing decisions. In a similar study, Aerni et al.38 offered three clearly labeled types of corn bread (organic, conventional and GM) at five different market stands across the French and German-speaking parts of Switzerland. Since Bt-11, a variety of GM corn, was approved for human consumption in Switzerland since 1998, the researchers were able to offer a real GM product for sale. Consumers were more likely to buy organic corn bread and less likely to buy the bread made with GM corn when compared with the conventional corn bread. Varying the price also affected buying behavior: shoppers bought more GM corn bread when it was cheap, and bought less of it when it was as expensive as the organic bread. However, price variation did not fully explain buying patterns as 26% of consumers bought at least one loaf of GM corn bread when it was the cheaper price, but 20% still purchased at least one loaf at the higher price. Researchers speculated that consumers might have appreciated the freedom of choice and transparency, were convinced of GM technology’s usefulness or were simply curious. However, it was evident from their research that some consumers would purchase GM foods if given the opportunity. Comparable market studies have been conducted in other countries, albeit without real GM food products. Knight et al.39
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results and the results of surveys of French consumers indicating an overwhelming opposition to GM foods.18 Lusk et al.31 assessed the public acceptance of GM foods by studying the consumer’s willingness to pay and willingness to accept the foods. The authors determined the percentage premium for non-GM food over GM food through a meta-analysis of 25 published research studies that used a range of methods for estimating valuation, including auctions, payment cards and dichotomous choice, in real or hypothetical elicitations. Percentage premiums for non-GM food ranged from a low of −67% —meaning that consumers valued the GM-food over the non-GM food—to a high of +784%, with an average premium across all valuation studies of 42%. Overall, consumers could be viewed as being averse to GM foods, but the complexity of consumer choice was apparent when the more detailed information was considered. European consumers had valuations for nonGM food 29% higher than US consumers. Premiums elicited in non-hypothetical contexts were lower than premiums elicited in hypothetical scenarios. Willingness to accept non-GM premiums exceeded willingness-to-pay valuations by 59%. Premiums were also dependent on the type of food; for example, premiums for non-GM oil were 49% lower than premiums for nonGM meat, signifying less concern over GM oil than GM meat. Influence on acceptance or intention to purchase by food type was also noted by Spence and Townsend13 who surmised that the results they observed concerning GM chocolates—a luxury food item—could have been different if another type of food had been studied. The econometric model that Lusk et al.31 created, controlling for consumer characteristics, method used to elicit consumer valuation, and characteristics of the food being valued, was able to explain more than 89% of the variation in existing premium estimates for non-GM over GM food. While valuation studies performed in developed countries of GM foods that have similar non-GM versions already commercially available have revealed somewhat mixed results, research examining the interests of consumers in developing countries toward GM foods with nutritional enhancements to address significant public health concerns experienced in these regions has produced more positive results. De Steur et al.32 used open-ended valuation questions in intercept interviews with randomly selected participants from three different shopping venues in Shanxi Province, China, to assess consumers’ willingness to accept GM rice with high folate content. Shanxi Province has one of the world’s highest rates of neural tube defects, which is a common congenital malformation that is alleviated by adequate maternal folate intake prior to and during pregnancy. De Steur et al.32 found that more than 62% of the consumers interviewed were willing to accept the GM rice, and were even willing to pay an average premium of 34% for it over the price of conventional rice. These results were reinforced by a subsequent experimental auction study with 251 women of childbearing age from Shanxi Province, in which bidding behavior revealed that participants were prepared to pay a premium of 33.7% for folate-enhance GM rice over regular rice.33 Similarly, valuation studies examining Golden Rice, modified with enhanced β-carotene content as a method to help alleviate Vitamin A deficiency, revealed that consumers in India and China
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do, as measured in typical surveys. The majority of consumers in most countries participating claimed that they were aware of the labeling requirement for GM ingredients in food, but only half of the consumers questioned admitted to reading product labels. In addition, many of the consumers did not take care in avoiding GM products despite indicating that it mattered to them that the products they purchased were GM-free. To illustrate this lack of care, researchers determined that 21% of consumers in four of the countries (Czech Republic, the Netherlands, Poland and Spain) who believed they had purchased GM products had actually done so, and 23% who believed they had purchased GM products had not; of the consumers who did actually purchase GM-labeled products, 48% claimed they would not buy these products. Point-of-purchase records of shopping behavior, rather than selfreported intentions to purchase—or not purchase—GM products therefore provided an instructive and highly reliable indicator of consumer acceptance and willingness to purchase GM foods. Consumer tasting experiments could be considered as real-life equivalents to willing-to-accept valuations, and a complement to the information gleaned through point-of-purchase observations. Townsend and Campbell40 conducted one such experiment in the United Kingdom, in which 100 participants who had been topicblind recruited, meaning that they were not aware that the focus of the study would be on GM food, were asked to compare the taste and appearance of a traditionally-grown apple, an organic apple and a GM apple. Participants were not told which apple was which, although in reality all three apples were traditionally grown. Although the researchers varied the false attribute of the GM apple between a health benefit (preventing tooth decay) and a money-saving benefit (delayed onset of rot), no difference in the outcome measures were observed between the participants. In fact, 93% of the participants willingly tasted what they believed to be GM food despite the option to decline to do so, and 48% of participants indicated they would buy GM food in the future. The researchers also noted the 85.7% of participants who stated they would not purchase GM food still tasted what they believed to be a GM apple. These surprising results may have indicated that the participants had a range of possible attitudes about GM foods, and that those with mild opposition may accept GM foods despite the intent to avoid their purchase.40 Lähteenmäki et al.41 also assessed the willingness of 738 consumers in Denmark, Finland, Norway and Sweden to taste cheese they believed to be a GM product, although it had been falsely labeled as such. Although the attitudes of the participants were generally negative toward the use of gene technology in food production, only two of the participants refused to taste the cheese labeled as GM. In this study, the researchers also concluded that consumers who did not strongly object to GM foods may select them if they are presented as real product alternatives.
Providing Consumers with Sufficient Information Would consumers choose GM foods if given to the opportunity to do so, and the tools with which to make an informed choice? The valuation research conducted by Depositario et al.36
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investigated the buying behavior of GM food products labeled with clearly stated consumer benefits in six countries—New Zealand, Sweden, Belgium, France, Germany and the United Kingdom—purported to have negative public perceptions of GM technology. The researchers set up real roadside fruit stalls to offer shoppers choice in a genuine shopping situation and to minimize the influence of social desirability bias. Conventional fruit was labeled as organic, spray-free genetically modified and conventional (or appropriate translations thereof) and combined with three different price levels (prevailing market price, +15% and −15%) to create a balanced fractional factorial design with nine price-label offerings. When fruit was sold at the prevailing market price, the largest share of fruit purchased was that labeled as organic. However, when the organic fruit sold at a premium and the spray-free GM fruit at a discount—considered the most likely real-life scenario by the researchers—the GM fruit gained the highest market share at stalls in all countries except Belgium. It was concluded that consumers were willing to purchase GM fruit if there was a price advantage coupled with consumer benefit (e.g., spray-free). Nielsen27 also found that consumers would choose GM-labeled foods if presented with consumer benefits in a study of buying behavior of conventional fries compared with fries labeled as produced from late-blight resistant GM potatoes; in this study 22.4% consumers at mobile fast food stands in Germany chose GM fries and 21.1% had no preference when given the choice to purchase fries fictitiously labeled as being from “environmentally friendlier genetically modified potatoes (much less sprays).” Since multiple opinion polls continue to indicate the majority of Europeans would avoid GM foods in the marketplace, some European research studies have examined consumers’ actual purchasing behavior through point of sales methods to determine whether these expressed sentiments are truly reflective of consumers’ food selection behavior. Kalaitzandonakes et al.6 collected national-level point-of-sale grocery store scanner data from supermarkets across the Netherlands that had sales of $2 million or more. The data set spanned 260 consecutive weeks, beginning in April 1997 and ending in April 2002, and included information on four categories of products containing GM ingredients as well as those that did not. At the ninth week of the study (June 1997), labels were introduced on relevant products containing GM soybean ingredients, and then removed in May 2000 as food manufacturers sourced non-GM ingredients. Analysis of the scanner data revealed that, in aggregate, Netherlands consumers did not significantly change their purchasing behavior toward foods that gained labels indicating the presence of GM ingredients, nor did they substantially alter their purchasing behavior once the labels were removed. There were neither gradual shifts away from foods with GM-labeling, nor any abrupt adjustments. In a similar approach, barcode analyses of consumer purchases were compared with GM or non-GM labeled products as part of a larger study of GM food product availability in ten European states during the period of May 2006 through October 2008.17 After making their purchases, consumers were asked about what they actually did when faced with options of buying GM or GM-free products—not just what they would hypothetically
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opinion surveys at the time of its introduction recorded widespread concern about food safety and biotechnology. Flipse and Osseweijer47 pointed out that providing the public with information is no guarantee of balanced public opinion, but without correct information the public is unable to change its reflection and may continue to base opinions on incomplete or incorrect information.
Conclusion The divergence between consumer attitudes (and what they say they do) and their actual behavior is not uncommon. Increasingly, research has sought to elucidate consumer behavior by fine-tuning models and incorporating additional factors that may influence the trajectory between intention and action. Real choice experiments offer potentially improved estimations of consumer behavior, but may be more time consuming and expensive to conduct than other methods such as surveys and valuation studies. However, research conducted in European retail environments has demonstrated that many consumers do purchase or are willing to purchase GM foods, in direct contrast to survey results indicating the majority of Europeans would avoid GM foods in the marketplace. Similar disparities have been observed in other countries as well, as discussed in this paper. Valuation and real choice experiments have also indicated that consumers may choose GM foods over conventional or organic foods, particularly if there are benefits in doing so such as less pesticide residue, lower cost or nutritional enhancement. Köster30 suggested that those who wish to better understand the complexities of food choice should look to the insights gained over the past 20 y in the fields of physiology and psychology. Köster argued that past behavior, habits and hedonic appreciation are better predictors of human behavior than attitudes and intentions, and that many food habits and food choice behaviors are rooted in childhood and are not fully accessible to conscious control. Research by Höfling48 seems to support these arguments, as food choices and behavior of participants toward GM foods were more strongly influenced by hunger or disgust than by conscious evaluations of food. Future work in this area would benefit from a multidisciplinary approach to bring methods that incorporate evolutionary, familial and social community influences into the field of consumer behavior and food-related decision-making. Disclosure of Potential Conflicts of Interest
No potential conflict of interest was disclosed.
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suggested that consumers’ willingness to pay for GM foods can be negatively influenced not only by information describing the risks of products derived through GE, but also by information considered as balanced that presents both the risks and benefits in a two-sided manner. In contrast, providing positive information to the participants in their study had only a marginal effect on willingness to pay over providing no information at all, leading the researchers to conclude that information dissemination campaigns concerning Golden Rice should be curtailed until consumer information requirements for more positively influencing consumer acceptance can be identified.36 However, as demonstrated by the research examples above, in which participants purchased or tasted GM-labeled foods despite reported negative attitudes toward the technology, the caution raised by Depositario et al.36 may have been unnecessarily generated through ineffective measurement of consumer behavior toward GM foods. Making food choices in a research environment, regardless of how well that environment is constructed, seldom is equivalent to buying food as part of the normal routine of life where purchases are often hurried with little time or inclination for deep thought. Familiarity of products from previous purchases and the perception that the food on grocery stores shelves is safe to eat are deterrents to label-reading by consumers.17 Nevertheless, labels are viewed as a key source of information for consumers and can also assist in the perception of personal control with respect to food selection.42,43 Labeling can also be used to provide additional information about GM technologies, thereby raising awareness and improving transparency.43 Using the TPB model, Spence and Townsend13 found that an increasing PBC negatively impacted intentions, suggesting that labeling GM foods would likely decrease consumers’ intentions to try GM foods. Actual experiences with real GM foods labeled as such would seem to contradict this. For example, labeled GM tomato purée that was sold side-by-side with non-GM brands in the United Kingdom from 1996 to 1999 outsold the non-GM brands that were offered at the same price, possibly due to the 10% larger can size for the GM product, used to pass on the process cost savings to consumers, and better taste.44 A Japanese supermarket chain that began offering labeled GM foods in 2000 reported no significant impact on sales after one year, despite surveys reporting that the majority of Japanese consumers did not support GM products.45 Similarly, Aldrich and Blisard46 reported that milk sales in the US remained steady after rBST was made available to dairy producers in 1994. rBST is a version of the bovine growth hormone that stimulates milk production, produced by genetically altered bacteria in the laboratory, and public
1. Kloor K. Mark Lynas responds to his detractors. Discovery Magazine. Collide-aScape blog [Internet]. 2013 January 31. Waukesha (WI): Kalmbach Publishing Co.; c2013 [cited 2013 Apr 22]. Available from: http://blogs.discove r m a g a z i n e .c om / c o l l i d e a s c a p e / 2 013 / 01/ 31/ mark-lynas-responds-to-his-detractors/ 2. Lynas M. Lecture to Oxford Farming Conference. Mark Lynas [Internet]. 2013 January 3. c2013 [cited 2013 Apr 22]. Available from: http://www.marklynas.org/2013/01/lecture-to-oxford-farming-conference-3-january-2013/ 3. Storr W. Mark Lynas: truth, treachery and GM food. The Observer [Internet]. 2013 March 9 [cited 2013 Apr 22]. Available from: http://www. g u a r d i a n .c o.u k / e nv i r on m e nt / 2 013 / m a r / 0 9 / mark-lynas-truth-treachery-gm 4. Chandon P, Morwitz VG, Reinantz WJ. Do intentions really predict behaviour? Self-generated validity effects in survey research. J Mark 2005; 69:1-14; http://dx.doi.org/10.1509/jmkg.69.2.1.60755 5. Manski CF. The use of intentions data to predict behavior: a best-case analysis. J Am Stat Assoc 1990; 85:934-40; http://dx.doi.org/10.1080/01621459.199 0.10474964 6. Kalaitzandonakes N, Marks LA, Vickner SS. Sentiments and acts towards genetically modified foods. Int J Biotechnol 2005; 7:161-77; http://dx.doi. org/10.1504/IJBT.2005.006452 7. European Commission. Standard Eurobarometer [Internet]. Brussels: European Commission; 2013 [cited 2013 Apr 22]. Available from http://ec.europa. eu/public_opinion/archives/eb_arch_en.htm 8. European Commission. Eurobarometer 73.1: Biotechnology. Special Eurobarometer 34.1/Wave 73.1–TNS Opinion & Social [Internet]. Brussels: European Commission; 2010 [cited 2013 Apr 22]. Available from http://ec.europa.eu/public_opinion/ archives/ebs/ebs_341_en.pdf 9. Gaskell G, Stares S, Allansdottir A, Allum N, Corchero C, Jackson J. Europeans and biotechnology in 2005: patterns and trends. Final report on Eurobarometer 64.3 [Internet]. Brussels: European Commission; 2006 [cited 2013 Apr 22]. Available from http://ec.europa.eu/research/biosociety/pdf/ eb_64_3_final_report_second_edition_july_06.pdf 10. Chern WS, Rickertsen K, Tsuboi N, Fu T. Consumer acceptance and willingness to pay for genetically modified vegetable oil and salmon: a multiple-country assessment. AgBioForum 2002 [cited 2013 Apr 22];5(3):105-112. Available from: http://agbioforum.org/v5n3/v5n3a05-chern.htm 11. International Food Information Council Foundation. 2012 Consumer Perceptions of Technology Survey; 2012 [cited 2013 Apr 22]. Available from http:// www.foodinsight.org/Resources/Detail.aspx?topic= 2012ConsumerPerceptionsofTechnologySurvey 12. Powell DA, Blaine K, Morris S, Wilson J. Agronomic and consumer considerations for Bt and conventional sweet-corn. Br Food J 2003; 105:700-13; http:// dx.doi.org/10.1108/00070700310506254 13. Spence A, Townsend E. Examining consumer behavior toward genetically modified (GM) food in Britain. Risk Anal 2006; 26:657-70; PMID:16834625; http://dx.doi.org/10.1111/j.1539-6924.2006.00777.x 14. Hui W. Self-generated validity, framing effects, and survey research in IS. Nottingham University Business School Research Paper No. 2010-12; 2010 [cited 2013 Mar 17]. Available from http://papers. ssrn.com/sol3/papers.cfm?abstract_id=1612263 15. Tourangeau R, Rasinski KA. Cognitive processes underlying context effects in attitude measurement. Psychol Bull 1988; 103:299-314; http://dx.doi. org/10.1037/0033-2909.103.3.299
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16. Feldman JM, Lynch JG. Self-generated validity and other effects of measurement on belief, attitude, intention, and behaviour. J Appl Psychol 1988; 73:421-35; http://dx.doi.org/10.1037/0021-9010.73.3.421 17. European Commission. Do European consumers buy GM foods? Consumerchoice Final Report. European Commission Framework Programme 6 [Internet]. London: King’s College London; 2008 [cited 2013 Apr 22]. Project No.: 518435. Available from: http:// www.kcl.ac.uk/consumerchoice 18. Noussair C, Robin S, Ruffieux B. Do consumers really refuse to buy genetically modified food? Econ J 2004; 114:102-20; http://dx.doi. org/10.1046/j.0013-0133.2003.00179.x 19. Sagoff M. The economy of the earth: Philosophy, law, and the environment. Cambridge: Cambridge University Press; 1988:53. 20. Sprott DE, Spangenberg ER, Block LG, Fitzsimons GJ, Morwitz VG, Williams P. The question–behavior effect: what we know and where we go from here. Soc Influence 2006; 1:128-37; http://dx.doi. org/10.1080/15534510600685409 21. Spangenberg ER. Increasing health club attendance through self-prophecy. Mark Lett 1997; 8:23-31; http://dx.doi.org/10.1023/A:1007977025902 22. Ajzen I. From intentions to actions: a theory of planned behavior. In: Kuhl J, Beckmann J, eds. Action–control: From Cognition to Behavior. Heidelberg: Springer, 1985: 11-39. 23. Ajzen I. The theory of planned behavior. Organ Behav Hum Decis Process 1991; 50:179-211; http:// dx.doi.org/10.1016/0749-5978(91)90020-T 24. Sparks P, Shepherd R, Frewer LJ. Assessing and structuring attitudes toward the use of gene technology in food production: the role of perceived ethical obligation. Basic Appl Soc Psych 1995; 16:267-85; http:// dx.doi.org/10.1207/s15324834basp1603_1 25. Cook AJ, Kerr GN, Moore K. Attitudes and intentions towards purchasing GM food. J Econ Psychol 2002; 23:557-72; http://dx.doi.org/10.1016/ S0167-4870(02)00117-4 26. Ajzen I. The theory of planned behaviour: reactions and reflections. Psychol Health 2011; 26:1113-27; PMID:21929476; http://dx.doi.org/10.1080/08870 446.2011.613995 27. Nielsen T. Consumer buying behavior of genetically modified fries in Germany. J Food Prod Mark 2013; 19:41-53; http://dx.doi.org/10.1080/10454446.2013 .739552 28. Paasovaara R, Luomala HT. Enticing the effects of consumer values on actual choices of food products by applying the Value Activation Theory: chasing ghosts? Adv Consum Res 2009; 8:202-7 29. Rimal AP, McWatters KH, Hashim IB, Fletcher SM. Intended vs. actual purchase behavior for irradiated beef. J Food Prod Mark 2004; 10:1-15; http://dx.doi. org/10.1300/J038v10n04_01 30. Köster EP. Diversity in the determinants of food choice: a psychological perspective. Food Qual Prefer 2009; 20:70-82; http://dx.doi.org/10.1016/j. foodqual.2007.11.002 31. Lusk JL, Jamal M, Kurlander L, Roucan M, Taulman L. A meta-analysis of genetically modified food valuation studies. Journal of Agricultural and Resource Economics 2005; 30:28-44 32. De Steur H, Gellynck X, Storozhenko S, Liqun G, Lambert W, Van Der Straeten D, Viaene J. Willingness-to-accept and purchase genetically modified rice with high folate content in Shanxi Province, China. Appetite 2010; 54:118-25; PMID:19815041; http://dx.doi.org/10.1016/j.appet.2009.09.017
33. De Steur H, Gellynck X, Feng S, Rutsaert P, Verbeke W. Determinants of willingness-to-pay for GM rice with health benefits in a high-risk region: evidence from experimental auctions for folate biofortified rice in China. Food Qual Prefer 2012; 25:87-94; http:// dx.doi.org/10.1016/j.foodqual.2012.02.001 34. Deodhar S, Ganesh S, Chern W. Emerging markets for GM foods: a study of consumer’s willingness to pay in India. Int J Biotechnol 2008; 10:570-87; http://dx.doi.org/10.1504/IJBT.2008.022493 35. Li Q, Curtis K, McCluskey J, Wahl T. Consumer attitudes toward genetically modified foods in Beijing, China. AgBioForum 2002 [cited 2013 Apr 22];5(4):145-52. Available from: http://www.agbioforum.org/v5n4/v5n4a03-wahl.htm 36. Depositario DPT, Nayga RM Jr., Wu X, Laude TP. Effects of information on consumers’ willingness to pay for golden rice. Asian Econ J 2009; 23:457-76; http://dx.doi.org/10.1111/j.1467-8381.2009.02021.x 37. International Rice Research Institute. FAQ, resources and links; 2012 [cited 2013 Apr 22]. Available from. http://www.irri.org/index.php?option=com_k2&vi ew=item&layout=item&id=10245&Itemid=100574 &lang=en 38. Aerni P, Scholderer J, Ermen D. How would Swiss consumers decide if they had freedom of choice? Evidence from a field study with organic, conventional and GM corn bread. Food Policy 2011; 36:8308; http://dx.doi.org/10.1016/j.foodpol.2011.08.002 39. Knight JG, Mather DW, Holdsworth DK, Ermen DF. Acceptance of GM food--an experiment in six countries. Nat Biotechnol 2007; 25:507-8; PMID:17483829; http://dx.doi.org/10.1038/ nbt0507-507 40. Townsend E, Campbell S. Psychological determinants of willingness to taste and purchase genetically modified food. Risk Anal 2004; 24:1385-93; PMID:15563302; http://dx.doi. org/10.1111/j.0272-4332.2004.00533.x 41. Lähteenmäki L, Grunert K, Ueland Ø, Åström A, Arvola A, Bech-Larsen T. Acceptability of genetically modified cheese presented as real product alternative. Food Qual Prefer 2002; 13:523-33; http://dx.doi. org/10.1016/S0950-3293(01)00077-5 42. Costa-Font M, Gil JM, Traill WB. Consumer acceptance, valuation of and attitudes towards genetically modified food: review and implications for food policy. Food Policy 2008; 33:99-111; http://dx.doi. org/10.1016/j.foodpol.2007.07.002 43. Frewer LJ, Howard C, Aaron I. Consumers acceptance of transgenic crops. Pestic Sci 1998; 52:388-93; http://dx.doi.org/10.1002/(SICI)10969063(199804)52:43.0.CO;2-F 44. Nunn J. What lies behind the GM label on UK foods. AgBioForum 2000 [cited 2013 Apr 22];3(4), 250254. Available from: http://www.agbioforum.org/ v3n4/v3n4a12-nunn.htm 45. Hur J. New GMO rules may curb Japan’s appetite for US corn. Reuters. 2001 Mar 29. Available from: http://www.biotech-info.net/curbing_appetites.html 46. Aldrich LM, Blisard N. Consumer acceptance of biotechnology: lessons from the rBST experience. United States Department of Agriculture, Economic Research Service; 1998. No.: 33663. 47. Flipse SM, Osseweijer P. Media attention to GM food cases: An innovation perspective. Public Underst Sci 2013; 22:185-202; PMID:23833024; http://dx.doi. org/10.1177/0963662512458631 48. Höfling A. Beggars cannot be choosers–the influence of food deprivation on food related disgust. [dissertation] Würzburg: Universität Würzburg; 2009 [cited 2013 Mar 17]. Available from: http://opus.bibliothek.uni-wuerzburg.de/volltexte/2009/3460/pdf/ Hoefling_Diss2008_OPUS.pdf
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References
GM Crops & Food: Biotechnology in Agriculture and the Food Chain Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/kgmc20
Surveys suck a
Douglas A Powell a
Powell Food Safety; Brisbane, Australia Published online: 12 Nov 2013.
To cite this article: Douglas A Powell (2013) Surveys suck, GM Crops & Food: Biotechnology in Agriculture and the Food Chain, 4:3, 195-201, DOI: 10.4161/gmcr.26777 To link to this article: http://dx.doi.org/10.4161/gmcr.26777
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Special Issue: Consumer Affairs
Special Issue: Consumer Affairs
GM Crops and Food: Biotechnology in Agriculture and the Food Chain 4:3, 195–201; July–December 2013; © 2013 Landes Bioscience
Surveys suck
Consumer preferences when purchasing genetically engineered foods Douglas A Powell
Keywords: genetically modified, GM food, consumer behavior, theory of planned behavior
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Abbreviations: GE, genetic engineering; GM, genetically modified; GMO, genetically modified organism; PBC, perceived behavioral control; TPB, Theory of Planned Behavior
Many studies have attempted to gauge consumers’ acceptance of genetically engineered or modified (GM) foods. Surveys, asking people about attitudes and intentions, are easy-to-collect proxies of consumer behavior. However, participants tend to respond as citizens of society, not discrete individuals, thereby inaccurately portraying their potential behavior. The Theory of Planned Behavior improved the accuracy of self-reported information, but its limited capacity to account for intention variance has been attributed to the hypothetical scenarios to which survey participants must respond. Valuation methods, asking how much consumers may be willing to pay or accept for GM foods, have revealed that consumers are usually willing to accept them at some price, or in some cases willing to pay a premium. Ultimately, it’s consumers’ actual—not intended—behavior that is of most interest to policy makers and business decision-makers. Real choice experiments offer the best avenue for revealing consumers’ food choices in normal life.
Introduction Mark Lynas has strong opinions about genetic engineering (GE). By his own admission, the British author and environmental activist was a dedicated campaigner against GE in the 1990s, helping to destroy test fields of genetically modified (GM) crops, pronouncing the risks of GE in television and radio interviews, and penning numerous articles on “the evils of Genetically Modified Organisms [GMOs]” (see also http://www.guardian. co.uk/environment/2013/mar/09/mark-lynas-truth-treacherygm). In January 2013, he caused substantial media and Internet buzz by delivering a lecture to the Oxford Farming Conference in which he apologized for his years of anti-GE actions and announced his support of GM as a means to decrease the impact of agricultural production on the environment and combat nutritional deficiencies in impoverished populations around the world.1-3 Although high-profile public proclamations about Correspondence to: Douglas A Powell; Email: [email protected] Submitted: 06/17/2013; Revised: 09/17/2013; Accepted: 10/10/2013 http://dx.doi.org/10.4161/gmcr.26777
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GMOs are not uncommon from many sides of the debate, how influential on, or reflective of, the broader sentiment such public proclamations may be is fodder for psychological and social influence researchers. How the consuming public actually behaves relative to their own attitudes and convictions—or those of the prevailing public—are of particular interest to behavioral scientists, public policymakers and business marketers. How to predict a consumer’s future behavior based on current measurements of intentions or actions is the holy grail of social science research. This paper offers a review of methodologies for assessing consumer behavior as they relate to GM foods, and demonstrates how inappropriate assessment can lead to erroneous conclusions about the public’s acceptance of GM foods and restrict consumers’ choices.
Attitudes, Intentions, and Planned Behaviors Surveys are a well-established method through which to measure public opinions and attitudes. Asking people about their intentions serves as easy-to-collect proxies of behavior.4,5 The designs and administrators of surveys vary widely, ranging from in-depth studies by academic researchers and government agencies to up-to-the-minute polling by media organizations.6 The selection of respondents who are representative of a larger population allows the results to be extrapolated to this larger group. The Eurobarometer is one example of this methodology by which data on a population’s perceptions has been gathered in the European Union’s member states since 1973.7 Public opinion on biotechnology, including genetic modification, is measured through a special Eurobarometer; the 2010 survey was the seventh in the series since 1991.8 In 2010, 84% of Europeans across 27 member states had heard of GM food; of those aware of GM food, 70% agreed that it is fundamentally unnatural, and 61% disagreed with the statement that the development of GM food should be encouraged. Survey results indicated that, overall, Europeans did not see the benefits of genetically modified food and considered them unsafe or harmful. These findings were consistent with previous issues of the Eurobarometer on biotechnology in which survey respondents in most European countries were generally opposed to agricultural biotechnologies and GM food.9 According to the sixth issue, published in 2006, Europeans and Canadians hold similar negative
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also possible that asking questions will reduce the strength of the relationship between intention and behavior if it does not align with perceived social norms.20 However, adjustment mechanisms can be employed to mitigate the impacts of such measurementreactivity effects on behavior models.4 Despite the strong relationship between attitudes and behaviors, it is widely recognized that the two do not directly correspond. The Theory of Planned Behavior (TPB) is one of the most frequently used frameworks to link attitudes with behavior and allows compensation for other factors beyond attitude that contribute to behavior. TPB is based on the premise that behavior results from intentions that are derived from attitudes toward the behavior, subjective norms and perceived behavioral control (PBC).22 However, behavioral achievement depends jointly on intention and PBC (Fig. 1).13,23 The three determinants of intention are conceptually independent: • attitude toward the behavior refers to whether a person has a favorable or unfavorable attitude toward or appraisal of the behavior in question; • subjective norm is the perceived social pressure for or against carrying out the behavior; and • perceived behavioral control (PBC) is the sense of ease or difficulty of performing the behavior, and reflects past experiences as well as impediments and obstacles.23 Under the TPB model, an individual’s intention to perform a behavior is strengthened by a more favorable attitude, agreement with social norms, and greater PBC.23 The model is often adjusted by including additional components, for example moral norms (i.e., personal norms of right vs. wrong), self-identity concepts (i.e., personal or social identity) or affective influences such as emotional involvement.13 Sparks et al.24 assessed attitudes toward genetic modification based on the TPB, with perceived ethical obligation as an additional determinant of intention. A questionnaire was mailed to 2,000 randomly selected individuals in the United Kingdom; the response rate was 17%. Attitude was found to be the most strongly related of the model components to both the intention to eat GM food and the intention to support food production using gene technology; greater perceived ethical obligation to avoid GM foods was associated with lower expectations of eating GM foods. In a similar study, Cook et al.25 developed a postal survey to measure the intentions of residents of Canterbury, New Zealand to purchase GM foods based on the TPB model with self-identity as an additional determinant of intention. The model included a number of factors that the researchers hypothesized would have negative relationships with an individual’s intention to purchase GM foods, such as concern for the environment and one’s personal health, and intention to purchase organic foods. Although the response rate was low (22.4% of 1,200 surveys distributed), 60% of respondents had negative intentions toward purchasing GM foods while 10% of respondents had positive intentions. Attitude had the greatest influence on intention. Selfidentity, subjective norm and perceived behavioral control also significantly influenced intention. Respondents with concerns
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views on GM foods, while people in the US view them as more beneficial and less risky. These results are in agreement with other surveys that have been conducted in Europe, Canada and the US (for examples see refs. 10–12). When asked if they would consider purchasing food under a certain conditions, more than half of the Eurobarometer respondents would consider buying GM food if it was healthier or contained less pesticide residues than other foods and 49% might be persuaded if GM foods were more environmentally friendly; however, approval by relevant health authorities and better prices reportedly would have caused only 44% and 36% respectively to consider purchasing GM foods. One difficulty with surveys is that respondents are asked to form opinions and make choices about hypothetical scenarios. In this artificial environment, respondents may become susceptive to social desirability effects and demand characteristics, giving false answers to meet perceived expectations or avoid violating social norms.6,13 Self-report methods may be impacted by other method biases as well, such as common method variance, consistency motif and implicit theories, that may lead to inflated or deflated associations between stated responses and behavior and associated inferences.13,14 Cognitive biases may further obfuscate the relationship between survey responses and actual behavior.6 How questions are framed, the order in which they are presented and the contextual information provided may also influence how a respondent answers survey questions.6,15 Moreover, some consumers may have not had an intention about a specific behavior prior to being surveyed and may have formed the intention only when asked about it.16 This issue was highlighted in a multicountry study examining the intention of European consumers to buy GM food products, in which the researchers noted that the topic may have been of little interest to survey respondents until brought to their attention, and that respondents determined how to respond based on the framing of the question rather than through an established intention.17 In addition, Noussair et al.18 suggested that survey participants respond as citizens of society rather than as discrete individuals, providing judgments that are more reflective of their perceived role in a broader group rather than as a private consumer. In the citizen role, respondents may be more inclined to support their image of a good society, as opposed to private consumer role with the focus on self-interests and personal wants.19 Paradoxically, asking someone about their intentions to perform a future action may cause that person to change their behavior through a phenomenon known as self-generated validity or the question-behavior effect.4,20 In a study by Spangenberg,21 health club members who were asked to predict their use of the club facilities were found to increase their frequency of use for up to six months following the survey when compared with the non-surveyed control group. Chandon et al.4 cautioned that by measuring intentions through surveys, respondents form judgments that they might not otherwise form or might not access in their memory, and put more emphasis on intentions compared with other decision inputs such as tastes, mood and competitive products. Self-generated validity strengthens the association between intention and behavior, consequently leading to an overstatement of the predictive accuracy of the intention.4 It is
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about herbicide use in food production or food additives tended to not hold positive attitudes toward GM food purchase. Using their extension of the TPB model with the self-identity incorporated, the researchers determined that 166 of the responses (63.1%) were correctly predicted. Despite careful adjustments, a reasonably good fit of the TPB will only achieve correlation coefficients among the model’s constructs of about 0.60.26 Although the TPB model has provided substantial advancement in linking intentions to behavior, it is unlikely that the complexity of a consumer’s motivations and behavior can be fully determined through the simple mechanism of questioning intentions. Figure 1. Theory of Planned Behavior, adapted from Ajzen. 23 There are arguments in the published literature in support of moving away from the selfreported approach employed by surveys toward methods that measure actual purchasing behavior through equivalent gain behavioral lottery task in which varying monexperiments that offer varying prices and information that a etary options were offered as alternatives to a box of GM chococonsumer may encounter in a true marketplace (for examples lates or non-GM chocolates. The survey also queried participants see refs. 27–29). Köster30 argued that the TPB model, in which directly on the TPB constructs, such as: “How much control do actions are provoked by rational, conscious intentions, cannot be you feel you have over eating a GM free diet?” Research results adequately applied to frequent human behaviors such as eating, showed that the standard TPB model with only the original drinking and food choices, as they occur with little conscious determinants (Fig. 1) accounted for about 51% of the variance in control. Consequently, indirect methods of analysis that allow intentions, while including the additional determinants of selfthe study of natural, complex behavior in its totality, such as identity, moral norms and emotional involvement increased the situational analysis and observational methods, may be better amount of variance for which the model accounted to 66%. In suited to assessing the interactive integration of determinants of general, the participants’ attitudes toward GM foods were relatively neutral, in line with results of Eurobarometer studies in behavior.30 the British population. However, behavior was determined to Estimated Valuation Methods be much more positive than attitudes indicated: most participants were prepared to accept GM chocolates over some amount Noussair et al.18 questioned whether surveys can reflect actual of money. This was attributed to the format of the elicitation, purchase behavior when an individual’s decisions in a hypotheti- wherein the participant made a private decision rather than a cal situation may differ from a real commitment to purchase. For decision as a public citizen, and that the choice was real (parexample, most surveys do not ask respondents about what their ticipants received the options they chose, to encourage truthful purchase decisions would be at specific prices nor do they include responding) rather than hypothetical.13 subtle contextual influences that may influence an individual’s In a different valuation approach, Noussair et al.18 created an purchasing decisions. auction-like shopping environment to assess French consumers’ However, contingent valuation is a survey-based economic willingness to pay for similar types of biscuits that differed mainly technique that is used to probe respondents’ actual purchase deci- in their labeled content of GMOs. Participants were required to sions by asking how much they would be willing to pay or accept bid for real consumer goods, using money to denote their preferfor a particular good. Spence and Townsend13 used contingent ences – a mechanism that, in principle, permits true valuation to valuation to extend the TPB to examine consumers’ propensity be revealed rather than one that is inferred. The bid submitted to purchase non-GM vs. GM chocolates. Although the scenario in the auction was also used to weight the importance of the bisemployed was fictitious, since chocolates containing GM ingre- cuit characteristics to the participants, including taste, appeardients would not have been commercially available to the British ance and price, along with the GMO content. Thirty-five percent community involved in the study, requiring survey respondents of the participants were unwilling to purchase products labeled to assign monetary values to their choices provided a more real- as containing GMOs, while 23% were indifferent or valued the istic representation of consumers’ purchasing behavior in a retail presence of GMOs and 42% were willing to purchase foods with environment than the constructs of the TPB (i.e., intention and GMOs if they were sufficiently inexpensive. Participants were PBC) on their own. Recruitment of participants was topic-blind also influenced by brand names of the products; when brand in order to avoid self-selection of individuals with particular names were revealed, average bids increased for three of the four interest in GM food issues. Participants were provided with an products. Of note was the difference between these experimental
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were willing to pay premiums of 19.5% and 38% respectively for it over non-GM rice.34,35 However, Depositario et al.36 determined that the tone of information (e.g., positive, negative or two-sided) provided to participants in a valuation study with Philippine consumers substantially affected their willingness to pay a premium for Golden Rice vs. non-GM rice. With regulatory approval for commercial production and sale of Golden Rice by the Philippine government anticipated as early as 2014,37 whether consumer behavior related to GM rice estimated through valuation studies truly reflects real market behavior may soon be elucidated.
Real Choice Experiments Paasovaara and Luomala 28 described consumers’ food choices as complex processes influenced by an array of individual and environmental factors ranging from demographics and personality traits to social interactions and sensory attributes. They argued that the most reliable results will be achieved if choices are made in a real purchasing context rather than on paper or in scenarios where alternative product choices are not available. Powell et al.12 explored consumers’ purchasing behavior of GM vs. non-GM foods in an established farm market in Hillsburgh, Ontario Canada during the 2000 growing season. Both GM and non-GM corn varieties were grown at the farm where the market was located. Shoppers were presented with GM sweet corn sideby-side with conventionally-grown sweet corn, with signage on each bin outlining the differences between the two commodities, including the production practices required for each. Endof-season tallies determined that shoppers purchased about 50% more of the GM sweet corn compared with the conventional sweet corn. A limited number of intercept interviews were conducted with market shoppers who indicated that pesticide use— required more frequently on the conventional corn—was more of a concern than GE, but that taste and quality had the most influence on their purchasing decisions. In a similar study, Aerni et al.38 offered three clearly labeled types of corn bread (organic, conventional and GM) at five different market stands across the French and German-speaking parts of Switzerland. Since Bt-11, a variety of GM corn, was approved for human consumption in Switzerland since 1998, the researchers were able to offer a real GM product for sale. Consumers were more likely to buy organic corn bread and less likely to buy the bread made with GM corn when compared with the conventional corn bread. Varying the price also affected buying behavior: shoppers bought more GM corn bread when it was cheap, and bought less of it when it was as expensive as the organic bread. However, price variation did not fully explain buying patterns as 26% of consumers bought at least one loaf of GM corn bread when it was the cheaper price, but 20% still purchased at least one loaf at the higher price. Researchers speculated that consumers might have appreciated the freedom of choice and transparency, were convinced of GM technology’s usefulness or were simply curious. However, it was evident from their research that some consumers would purchase GM foods if given the opportunity. Comparable market studies have been conducted in other countries, albeit without real GM food products. Knight et al.39
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results and the results of surveys of French consumers indicating an overwhelming opposition to GM foods.18 Lusk et al.31 assessed the public acceptance of GM foods by studying the consumer’s willingness to pay and willingness to accept the foods. The authors determined the percentage premium for non-GM food over GM food through a meta-analysis of 25 published research studies that used a range of methods for estimating valuation, including auctions, payment cards and dichotomous choice, in real or hypothetical elicitations. Percentage premiums for non-GM food ranged from a low of −67% —meaning that consumers valued the GM-food over the non-GM food—to a high of +784%, with an average premium across all valuation studies of 42%. Overall, consumers could be viewed as being averse to GM foods, but the complexity of consumer choice was apparent when the more detailed information was considered. European consumers had valuations for nonGM food 29% higher than US consumers. Premiums elicited in non-hypothetical contexts were lower than premiums elicited in hypothetical scenarios. Willingness to accept non-GM premiums exceeded willingness-to-pay valuations by 59%. Premiums were also dependent on the type of food; for example, premiums for non-GM oil were 49% lower than premiums for nonGM meat, signifying less concern over GM oil than GM meat. Influence on acceptance or intention to purchase by food type was also noted by Spence and Townsend13 who surmised that the results they observed concerning GM chocolates—a luxury food item—could have been different if another type of food had been studied. The econometric model that Lusk et al.31 created, controlling for consumer characteristics, method used to elicit consumer valuation, and characteristics of the food being valued, was able to explain more than 89% of the variation in existing premium estimates for non-GM over GM food. While valuation studies performed in developed countries of GM foods that have similar non-GM versions already commercially available have revealed somewhat mixed results, research examining the interests of consumers in developing countries toward GM foods with nutritional enhancements to address significant public health concerns experienced in these regions has produced more positive results. De Steur et al.32 used open-ended valuation questions in intercept interviews with randomly selected participants from three different shopping venues in Shanxi Province, China, to assess consumers’ willingness to accept GM rice with high folate content. Shanxi Province has one of the world’s highest rates of neural tube defects, which is a common congenital malformation that is alleviated by adequate maternal folate intake prior to and during pregnancy. De Steur et al.32 found that more than 62% of the consumers interviewed were willing to accept the GM rice, and were even willing to pay an average premium of 34% for it over the price of conventional rice. These results were reinforced by a subsequent experimental auction study with 251 women of childbearing age from Shanxi Province, in which bidding behavior revealed that participants were prepared to pay a premium of 33.7% for folate-enhance GM rice over regular rice.33 Similarly, valuation studies examining Golden Rice, modified with enhanced β-carotene content as a method to help alleviate Vitamin A deficiency, revealed that consumers in India and China
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do, as measured in typical surveys. The majority of consumers in most countries participating claimed that they were aware of the labeling requirement for GM ingredients in food, but only half of the consumers questioned admitted to reading product labels. In addition, many of the consumers did not take care in avoiding GM products despite indicating that it mattered to them that the products they purchased were GM-free. To illustrate this lack of care, researchers determined that 21% of consumers in four of the countries (Czech Republic, the Netherlands, Poland and Spain) who believed they had purchased GM products had actually done so, and 23% who believed they had purchased GM products had not; of the consumers who did actually purchase GM-labeled products, 48% claimed they would not buy these products. Point-of-purchase records of shopping behavior, rather than selfreported intentions to purchase—or not purchase—GM products therefore provided an instructive and highly reliable indicator of consumer acceptance and willingness to purchase GM foods. Consumer tasting experiments could be considered as real-life equivalents to willing-to-accept valuations, and a complement to the information gleaned through point-of-purchase observations. Townsend and Campbell40 conducted one such experiment in the United Kingdom, in which 100 participants who had been topicblind recruited, meaning that they were not aware that the focus of the study would be on GM food, were asked to compare the taste and appearance of a traditionally-grown apple, an organic apple and a GM apple. Participants were not told which apple was which, although in reality all three apples were traditionally grown. Although the researchers varied the false attribute of the GM apple between a health benefit (preventing tooth decay) and a money-saving benefit (delayed onset of rot), no difference in the outcome measures were observed between the participants. In fact, 93% of the participants willingly tasted what they believed to be GM food despite the option to decline to do so, and 48% of participants indicated they would buy GM food in the future. The researchers also noted the 85.7% of participants who stated they would not purchase GM food still tasted what they believed to be a GM apple. These surprising results may have indicated that the participants had a range of possible attitudes about GM foods, and that those with mild opposition may accept GM foods despite the intent to avoid their purchase.40 Lähteenmäki et al.41 also assessed the willingness of 738 consumers in Denmark, Finland, Norway and Sweden to taste cheese they believed to be a GM product, although it had been falsely labeled as such. Although the attitudes of the participants were generally negative toward the use of gene technology in food production, only two of the participants refused to taste the cheese labeled as GM. In this study, the researchers also concluded that consumers who did not strongly object to GM foods may select them if they are presented as real product alternatives.
Providing Consumers with Sufficient Information Would consumers choose GM foods if given to the opportunity to do so, and the tools with which to make an informed choice? The valuation research conducted by Depositario et al.36
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investigated the buying behavior of GM food products labeled with clearly stated consumer benefits in six countries—New Zealand, Sweden, Belgium, France, Germany and the United Kingdom—purported to have negative public perceptions of GM technology. The researchers set up real roadside fruit stalls to offer shoppers choice in a genuine shopping situation and to minimize the influence of social desirability bias. Conventional fruit was labeled as organic, spray-free genetically modified and conventional (or appropriate translations thereof) and combined with three different price levels (prevailing market price, +15% and −15%) to create a balanced fractional factorial design with nine price-label offerings. When fruit was sold at the prevailing market price, the largest share of fruit purchased was that labeled as organic. However, when the organic fruit sold at a premium and the spray-free GM fruit at a discount—considered the most likely real-life scenario by the researchers—the GM fruit gained the highest market share at stalls in all countries except Belgium. It was concluded that consumers were willing to purchase GM fruit if there was a price advantage coupled with consumer benefit (e.g., spray-free). Nielsen27 also found that consumers would choose GM-labeled foods if presented with consumer benefits in a study of buying behavior of conventional fries compared with fries labeled as produced from late-blight resistant GM potatoes; in this study 22.4% consumers at mobile fast food stands in Germany chose GM fries and 21.1% had no preference when given the choice to purchase fries fictitiously labeled as being from “environmentally friendlier genetically modified potatoes (much less sprays).” Since multiple opinion polls continue to indicate the majority of Europeans would avoid GM foods in the marketplace, some European research studies have examined consumers’ actual purchasing behavior through point of sales methods to determine whether these expressed sentiments are truly reflective of consumers’ food selection behavior. Kalaitzandonakes et al.6 collected national-level point-of-sale grocery store scanner data from supermarkets across the Netherlands that had sales of $2 million or more. The data set spanned 260 consecutive weeks, beginning in April 1997 and ending in April 2002, and included information on four categories of products containing GM ingredients as well as those that did not. At the ninth week of the study (June 1997), labels were introduced on relevant products containing GM soybean ingredients, and then removed in May 2000 as food manufacturers sourced non-GM ingredients. Analysis of the scanner data revealed that, in aggregate, Netherlands consumers did not significantly change their purchasing behavior toward foods that gained labels indicating the presence of GM ingredients, nor did they substantially alter their purchasing behavior once the labels were removed. There were neither gradual shifts away from foods with GM-labeling, nor any abrupt adjustments. In a similar approach, barcode analyses of consumer purchases were compared with GM or non-GM labeled products as part of a larger study of GM food product availability in ten European states during the period of May 2006 through October 2008.17 After making their purchases, consumers were asked about what they actually did when faced with options of buying GM or GM-free products—not just what they would hypothetically
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opinion surveys at the time of its introduction recorded widespread concern about food safety and biotechnology. Flipse and Osseweijer47 pointed out that providing the public with information is no guarantee of balanced public opinion, but without correct information the public is unable to change its reflection and may continue to base opinions on incomplete or incorrect information.
Conclusion The divergence between consumer attitudes (and what they say they do) and their actual behavior is not uncommon. Increasingly, research has sought to elucidate consumer behavior by fine-tuning models and incorporating additional factors that may influence the trajectory between intention and action. Real choice experiments offer potentially improved estimations of consumer behavior, but may be more time consuming and expensive to conduct than other methods such as surveys and valuation studies. However, research conducted in European retail environments has demonstrated that many consumers do purchase or are willing to purchase GM foods, in direct contrast to survey results indicating the majority of Europeans would avoid GM foods in the marketplace. Similar disparities have been observed in other countries as well, as discussed in this paper. Valuation and real choice experiments have also indicated that consumers may choose GM foods over conventional or organic foods, particularly if there are benefits in doing so such as less pesticide residue, lower cost or nutritional enhancement. Köster30 suggested that those who wish to better understand the complexities of food choice should look to the insights gained over the past 20 y in the fields of physiology and psychology. Köster argued that past behavior, habits and hedonic appreciation are better predictors of human behavior than attitudes and intentions, and that many food habits and food choice behaviors are rooted in childhood and are not fully accessible to conscious control. Research by Höfling48 seems to support these arguments, as food choices and behavior of participants toward GM foods were more strongly influenced by hunger or disgust than by conscious evaluations of food. Future work in this area would benefit from a multidisciplinary approach to bring methods that incorporate evolutionary, familial and social community influences into the field of consumer behavior and food-related decision-making. Disclosure of Potential Conflicts of Interest
No potential conflict of interest was disclosed.
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suggested that consumers’ willingness to pay for GM foods can be negatively influenced not only by information describing the risks of products derived through GE, but also by information considered as balanced that presents both the risks and benefits in a two-sided manner. In contrast, providing positive information to the participants in their study had only a marginal effect on willingness to pay over providing no information at all, leading the researchers to conclude that information dissemination campaigns concerning Golden Rice should be curtailed until consumer information requirements for more positively influencing consumer acceptance can be identified.36 However, as demonstrated by the research examples above, in which participants purchased or tasted GM-labeled foods despite reported negative attitudes toward the technology, the caution raised by Depositario et al.36 may have been unnecessarily generated through ineffective measurement of consumer behavior toward GM foods. Making food choices in a research environment, regardless of how well that environment is constructed, seldom is equivalent to buying food as part of the normal routine of life where purchases are often hurried with little time or inclination for deep thought. Familiarity of products from previous purchases and the perception that the food on grocery stores shelves is safe to eat are deterrents to label-reading by consumers.17 Nevertheless, labels are viewed as a key source of information for consumers and can also assist in the perception of personal control with respect to food selection.42,43 Labeling can also be used to provide additional information about GM technologies, thereby raising awareness and improving transparency.43 Using the TPB model, Spence and Townsend13 found that an increasing PBC negatively impacted intentions, suggesting that labeling GM foods would likely decrease consumers’ intentions to try GM foods. Actual experiences with real GM foods labeled as such would seem to contradict this. For example, labeled GM tomato purée that was sold side-by-side with non-GM brands in the United Kingdom from 1996 to 1999 outsold the non-GM brands that were offered at the same price, possibly due to the 10% larger can size for the GM product, used to pass on the process cost savings to consumers, and better taste.44 A Japanese supermarket chain that began offering labeled GM foods in 2000 reported no significant impact on sales after one year, despite surveys reporting that the majority of Japanese consumers did not support GM products.45 Similarly, Aldrich and Blisard46 reported that milk sales in the US remained steady after rBST was made available to dairy producers in 1994. rBST is a version of the bovine growth hormone that stimulates milk production, produced by genetically altered bacteria in the laboratory, and public
1. Kloor K. Mark Lynas responds to his detractors. Discovery Magazine. Collide-aScape blog [Internet]. 2013 January 31. Waukesha (WI): Kalmbach Publishing Co.; c2013 [cited 2013 Apr 22]. Available from: http://blogs.discove r m a g a z i n e .c om / c o l l i d e a s c a p e / 2 013 / 01/ 31/ mark-lynas-responds-to-his-detractors/ 2. Lynas M. Lecture to Oxford Farming Conference. Mark Lynas [Internet]. 2013 January 3. c2013 [cited 2013 Apr 22]. Available from: http://www.marklynas.org/2013/01/lecture-to-oxford-farming-conference-3-january-2013/ 3. Storr W. Mark Lynas: truth, treachery and GM food. The Observer [Internet]. 2013 March 9 [cited 2013 Apr 22]. Available from: http://www. g u a r d i a n .c o.u k / e nv i r on m e nt / 2 013 / m a r / 0 9 / mark-lynas-truth-treachery-gm 4. Chandon P, Morwitz VG, Reinantz WJ. Do intentions really predict behaviour? Self-generated validity effects in survey research. J Mark 2005; 69:1-14; http://dx.doi.org/10.1509/jmkg.69.2.1.60755 5. Manski CF. The use of intentions data to predict behavior: a best-case analysis. J Am Stat Assoc 1990; 85:934-40; http://dx.doi.org/10.1080/01621459.199 0.10474964 6. Kalaitzandonakes N, Marks LA, Vickner SS. Sentiments and acts towards genetically modified foods. Int J Biotechnol 2005; 7:161-77; http://dx.doi. org/10.1504/IJBT.2005.006452 7. European Commission. Standard Eurobarometer [Internet]. Brussels: European Commission; 2013 [cited 2013 Apr 22]. Available from http://ec.europa. eu/public_opinion/archives/eb_arch_en.htm 8. European Commission. Eurobarometer 73.1: Biotechnology. Special Eurobarometer 34.1/Wave 73.1–TNS Opinion & Social [Internet]. Brussels: European Commission; 2010 [cited 2013 Apr 22]. Available from http://ec.europa.eu/public_opinion/ archives/ebs/ebs_341_en.pdf 9. Gaskell G, Stares S, Allansdottir A, Allum N, Corchero C, Jackson J. Europeans and biotechnology in 2005: patterns and trends. Final report on Eurobarometer 64.3 [Internet]. Brussels: European Commission; 2006 [cited 2013 Apr 22]. Available from http://ec.europa.eu/research/biosociety/pdf/ eb_64_3_final_report_second_edition_july_06.pdf 10. Chern WS, Rickertsen K, Tsuboi N, Fu T. Consumer acceptance and willingness to pay for genetically modified vegetable oil and salmon: a multiple-country assessment. AgBioForum 2002 [cited 2013 Apr 22];5(3):105-112. Available from: http://agbioforum.org/v5n3/v5n3a05-chern.htm 11. International Food Information Council Foundation. 2012 Consumer Perceptions of Technology Survey; 2012 [cited 2013 Apr 22]. Available from http:// www.foodinsight.org/Resources/Detail.aspx?topic= 2012ConsumerPerceptionsofTechnologySurvey 12. Powell DA, Blaine K, Morris S, Wilson J. Agronomic and consumer considerations for Bt and conventional sweet-corn. Br Food J 2003; 105:700-13; http:// dx.doi.org/10.1108/00070700310506254 13. Spence A, Townsend E. Examining consumer behavior toward genetically modified (GM) food in Britain. Risk Anal 2006; 26:657-70; PMID:16834625; http://dx.doi.org/10.1111/j.1539-6924.2006.00777.x 14. Hui W. Self-generated validity, framing effects, and survey research in IS. Nottingham University Business School Research Paper No. 2010-12; 2010 [cited 2013 Mar 17]. Available from http://papers. ssrn.com/sol3/papers.cfm?abstract_id=1612263 15. Tourangeau R, Rasinski KA. Cognitive processes underlying context effects in attitude measurement. Psychol Bull 1988; 103:299-314; http://dx.doi. org/10.1037/0033-2909.103.3.299
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16. Feldman JM, Lynch JG. Self-generated validity and other effects of measurement on belief, attitude, intention, and behaviour. J Appl Psychol 1988; 73:421-35; http://dx.doi.org/10.1037/0021-9010.73.3.421 17. European Commission. Do European consumers buy GM foods? Consumerchoice Final Report. European Commission Framework Programme 6 [Internet]. London: King’s College London; 2008 [cited 2013 Apr 22]. Project No.: 518435. Available from: http:// www.kcl.ac.uk/consumerchoice 18. Noussair C, Robin S, Ruffieux B. Do consumers really refuse to buy genetically modified food? Econ J 2004; 114:102-20; http://dx.doi. org/10.1046/j.0013-0133.2003.00179.x 19. Sagoff M. The economy of the earth: Philosophy, law, and the environment. Cambridge: Cambridge University Press; 1988:53. 20. Sprott DE, Spangenberg ER, Block LG, Fitzsimons GJ, Morwitz VG, Williams P. The question–behavior effect: what we know and where we go from here. Soc Influence 2006; 1:128-37; http://dx.doi. org/10.1080/15534510600685409 21. Spangenberg ER. Increasing health club attendance through self-prophecy. Mark Lett 1997; 8:23-31; http://dx.doi.org/10.1023/A:1007977025902 22. Ajzen I. From intentions to actions: a theory of planned behavior. In: Kuhl J, Beckmann J, eds. Action–control: From Cognition to Behavior. Heidelberg: Springer, 1985: 11-39. 23. Ajzen I. The theory of planned behavior. Organ Behav Hum Decis Process 1991; 50:179-211; http:// dx.doi.org/10.1016/0749-5978(91)90020-T 24. Sparks P, Shepherd R, Frewer LJ. Assessing and structuring attitudes toward the use of gene technology in food production: the role of perceived ethical obligation. Basic Appl Soc Psych 1995; 16:267-85; http:// dx.doi.org/10.1207/s15324834basp1603_1 25. Cook AJ, Kerr GN, Moore K. Attitudes and intentions towards purchasing GM food. J Econ Psychol 2002; 23:557-72; http://dx.doi.org/10.1016/ S0167-4870(02)00117-4 26. Ajzen I. The theory of planned behaviour: reactions and reflections. Psychol Health 2011; 26:1113-27; PMID:21929476; http://dx.doi.org/10.1080/08870 446.2011.613995 27. Nielsen T. Consumer buying behavior of genetically modified fries in Germany. J Food Prod Mark 2013; 19:41-53; http://dx.doi.org/10.1080/10454446.2013 .739552 28. Paasovaara R, Luomala HT. Enticing the effects of consumer values on actual choices of food products by applying the Value Activation Theory: chasing ghosts? Adv Consum Res 2009; 8:202-7 29. Rimal AP, McWatters KH, Hashim IB, Fletcher SM. Intended vs. actual purchase behavior for irradiated beef. J Food Prod Mark 2004; 10:1-15; http://dx.doi. org/10.1300/J038v10n04_01 30. Köster EP. Diversity in the determinants of food choice: a psychological perspective. Food Qual Prefer 2009; 20:70-82; http://dx.doi.org/10.1016/j. foodqual.2007.11.002 31. Lusk JL, Jamal M, Kurlander L, Roucan M, Taulman L. A meta-analysis of genetically modified food valuation studies. Journal of Agricultural and Resource Economics 2005; 30:28-44 32. De Steur H, Gellynck X, Storozhenko S, Liqun G, Lambert W, Van Der Straeten D, Viaene J. Willingness-to-accept and purchase genetically modified rice with high folate content in Shanxi Province, China. Appetite 2010; 54:118-25; PMID:19815041; http://dx.doi.org/10.1016/j.appet.2009.09.017
33. De Steur H, Gellynck X, Feng S, Rutsaert P, Verbeke W. Determinants of willingness-to-pay for GM rice with health benefits in a high-risk region: evidence from experimental auctions for folate biofortified rice in China. Food Qual Prefer 2012; 25:87-94; http:// dx.doi.org/10.1016/j.foodqual.2012.02.001 34. Deodhar S, Ganesh S, Chern W. Emerging markets for GM foods: a study of consumer’s willingness to pay in India. Int J Biotechnol 2008; 10:570-87; http://dx.doi.org/10.1504/IJBT.2008.022493 35. Li Q, Curtis K, McCluskey J, Wahl T. Consumer attitudes toward genetically modified foods in Beijing, China. AgBioForum 2002 [cited 2013 Apr 22];5(4):145-52. Available from: http://www.agbioforum.org/v5n4/v5n4a03-wahl.htm 36. Depositario DPT, Nayga RM Jr., Wu X, Laude TP. Effects of information on consumers’ willingness to pay for golden rice. Asian Econ J 2009; 23:457-76; http://dx.doi.org/10.1111/j.1467-8381.2009.02021.x 37. International Rice Research Institute. FAQ, resources and links; 2012 [cited 2013 Apr 22]. Available from. http://www.irri.org/index.php?option=com_k2&vi ew=item&layout=item&id=10245&Itemid=100574 &lang=en 38. Aerni P, Scholderer J, Ermen D. How would Swiss consumers decide if they had freedom of choice? Evidence from a field study with organic, conventional and GM corn bread. Food Policy 2011; 36:8308; http://dx.doi.org/10.1016/j.foodpol.2011.08.002 39. Knight JG, Mather DW, Holdsworth DK, Ermen DF. Acceptance of GM food--an experiment in six countries. Nat Biotechnol 2007; 25:507-8; PMID:17483829; http://dx.doi.org/10.1038/ nbt0507-507 40. Townsend E, Campbell S. Psychological determinants of willingness to taste and purchase genetically modified food. Risk Anal 2004; 24:1385-93; PMID:15563302; http://dx.doi. org/10.1111/j.0272-4332.2004.00533.x 41. Lähteenmäki L, Grunert K, Ueland Ø, Åström A, Arvola A, Bech-Larsen T. Acceptability of genetically modified cheese presented as real product alternative. Food Qual Prefer 2002; 13:523-33; http://dx.doi. org/10.1016/S0950-3293(01)00077-5 42. Costa-Font M, Gil JM, Traill WB. Consumer acceptance, valuation of and attitudes towards genetically modified food: review and implications for food policy. Food Policy 2008; 33:99-111; http://dx.doi. org/10.1016/j.foodpol.2007.07.002 43. Frewer LJ, Howard C, Aaron I. Consumers acceptance of transgenic crops. Pestic Sci 1998; 52:388-93; http://dx.doi.org/10.1002/(SICI)10969063(199804)52:43.0.CO;2-F 44. Nunn J. What lies behind the GM label on UK foods. AgBioForum 2000 [cited 2013 Apr 22];3(4), 250254. Available from: http://www.agbioforum.org/ v3n4/v3n4a12-nunn.htm 45. Hur J. New GMO rules may curb Japan’s appetite for US corn. Reuters. 2001 Mar 29. Available from: http://www.biotech-info.net/curbing_appetites.html 46. Aldrich LM, Blisard N. Consumer acceptance of biotechnology: lessons from the rBST experience. United States Department of Agriculture, Economic Research Service; 1998. No.: 33663. 47. Flipse SM, Osseweijer P. Media attention to GM food cases: An innovation perspective. Public Underst Sci 2013; 22:185-202; PMID:23833024; http://dx.doi. org/10.1177/0963662512458631 48. Höfling A. Beggars cannot be choosers–the influence of food deprivation on food related disgust. [dissertation] Würzburg: Universität Würzburg; 2009 [cited 2013 Mar 17]. Available from: http://opus.bibliothek.uni-wuerzburg.de/volltexte/2009/3460/pdf/ Hoefling_Diss2008_OPUS.pdf
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References
