Transfusion and Apheresis Science 51 (2014) 146–151

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Transfusion and Apheresis Science j o u r n a l h o m e p a g e : w w w. e l s e v i e r. c o m / l o c a t e / t r a n s c i

Blood donation fears inventory: development and validation of a measure of fear specific to the blood donation setting Jennifer M. Kowalsky, Christopher R. France *, Janis L. France, Elizabeth A. Whitehouse, Lina K. Himawan Department of Psychology, Ohio University, 200 Porter Hall, Athens, OH 45701, USA

A R T I C L E

I N F O

Article history: Received 23 September 2013 Received in revised form 4 April 2014 Accepted 25 July 2014 Keywords: Blood donation Fear Scale development

A B S T R A C T

Background and Objectives: Although individual differences in fear of stimuli related to blood donation is a key determinant of donor recruitment and retention, a donation-specific fear measure has yet to be developed. Materials and Methods: A donation-related fear measure was developed and tested on an initial sample of donors and non-donors, and then re-evaluated on a second sample to confirm the observed factor structure. Results: Analyses supported a four-factor structure, with subscales related to fear of: (1) syncopal symptoms, (2) blood and needles, (3) social evaluation, and (4) health screen results. Conclusion: The Blood Donation Fears Inventory is a novel measure to assess fears held by current and potential blood donors. © 2014 Elsevier Ltd. All rights reserved.

1. Introduction Fear during exposure to blood donation stimuli, as well as anxiety in anticipation of such exposure, have long been recognized as important contributors to the experience of syncopal and presyncopal symptoms among volunteer blood donors. As early as 1942, Brown and McCormack [1] noted that a significant number of blood donors who fainted were nervous prior to the donation. Similarly, Poles and Boycott [2] observed that nervous donors experienced greater frequency and severity of syncopal symptoms compared with non-nervous donors. In more recent studies, greater levels of fear have been associated with donors’ subjective report of syncopal symptoms [3–8] and an increased likelihood of phlebotomist interventions to mitigate syncopal symptoms, such as reclining the donor’s chair [4,6]. Moreover, fear of having blood drawn has been shown to be the strongest individual predictor of syncopal symptoms when compared against other known predictors such as donor age,

* Corresponding author. Tel.: +1 740-593-1079; fax: +1 740-593-0579. E-mail address: [email protected] (C.R. France). http://dx.doi.org/10.1016/j.transci.2014.07.007 1473-0502/© 2014 Elsevier Ltd. All rights reserved.

prior donation status, body mass, and estimated blood volume [7,8]. Pre-donation fear also predicts donor attrition, with the effects of fear having both direct negative effects on 1-year retention rates as well as indirect negative effects via increased risk for syncopal symptoms [9]. Despite the growing recognition of the importance of fear and anxiety in the blood donation context, there is currently no specific measure of blood donor fears. Early studies of fear and anxiety were purely observational, with researchers deciding whether the donor “appeared nervous” or, in some cases, disclosed that they were “nervous” [1,2]. Recent studies have directly assessed donor reports using adaptations of existing fear and anxiety measures such as the Medical Fear Survey (a broad measure of fear in medical settings), the Anxiety Sensitivity Index (a measure of attention to somatic symptoms in response to feared stimuli), and the Spielberger Trait Anxiety Inventory (a measure of anxiety as a stable, trait characteristic) [3,10–15]. Although these adapted measures have proven useful in predicting risk for syncopal symptoms, because they were not developed for the blood donation context they may not be capturing the full range of concerns that are present among blood donors. Accordingly, the

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goal of the present study was to conduct a sequential, construct-oriented, psychometric development and validation of a measure of fear for use specifically in the blood donation context. 2. Materials and methods 2.1. Participants Participants were recruited through an undergraduate research participation system where they could obtain course credit. Consistent with classical test theory, two separate samples were recruited for this study, for use with each of the two phases of analysis (i.e., exploratory and confirmatory) required for scale development [16]. The questionnaires were administered through an online data collection website (Qualtrics, Provo, UT). Accurate responding was screened using test questions throughout the survey (e.g., “This is a test question, please answer very afraid or anxious.”). Participants who missed any of the test questions were excluded from the analyses as they were determined to not be paying sufficient attention to the questionnaire. The first sample for the exploratory factor analysis was comprised of 247 participants. The majority of the sample self-identified as White (n = 219, 89%; Asian = 4%; Other = 3%; Black or African American = 3%; American Indian or Alaska Native = 1%), female (n = 174, 70%), and young adults (Mean age = 19 years, SD = 1.25, range = 18–28) with slightly more non-donors than donors (non-donors: n = 141, 57%; donors: n = 106, 43%). The second sample, which was used for the confirmatory factor analysis, was comprised of 455 participants. Demographically, this second sample was very similar to the first, with the majority of the sample being White (n = 424, 93%; Asian = 2%; Other = 3%; Black or African American = 2%; American Indian or Alaska Native = 0%), female (n = 292, 64%), and young adults (mean age = 19.4 years, SD = 2.85, range = 18–51). Consistent with the first sample, slightly more than half of this second sample had never donated blood (n = 253, 56%; donors: n = 202, 44%). Both samples of participants completed the pool of potential fear scale items and a brief demographic questionnaire. Due to the analyses being conducted, additional participants were necessary for the second sample compared with the first sample. Ethics approval for the study protocol was provided by the Ohio University Institutional Review Board. 2.2. Materials Donation-related fear items were derived, in part, from a comprehensive, meta-analysis of motivations and deterrents to donate blood [17]. This list of fears served as a starting point for scale item development, with individual items developed to represent each of the reported fears, including: blood; needles; experiencing syncopal symptoms; injury; negative impact on health; and contagion [17]. Given the social nature of blood donation, items reflecting the fear of social evaluation in the event of syncopal symptoms were also created. This resulted in a 53 item-pool, with a Likerttype rating scale for each item, using anchors of 1 “Not at all afraid or anxious” and 5 “Extremely afraid or anxious”.

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Both samples of participants began by reading informed consent forms and were given the opportunity to ask questions prior to proceeding. Next, both samples of participants completed a brief questionnaire that assessed basic demographic information (e.g., age, race, ethnicity, donation experience as measured by a yes or no response to “Have you ever donated blood before”) and the pool of 53 potential fear items. The second sample of participants also completed 10-item blood and injection subscales of the Medical Fears Survey (MFS) and a three-item scale of donation intention (i.e., “I intend to give blood in the next 8 weeks” unlikely – likely; “I have decided to give blood in the next 8 weeks” disagree – agree; and “I will try to give blood in the next 8 weeks” improbable – probable). Each of these scales demonstrated excellent internal consistency reliability (MFS Fear of Blood, α = 0.96; MFS Fear of Needles, α = 0.95; Donation intention, α = 0.95). 2.3. Statistical analysis The data analysis was comprised of two key phases: (1) the exploratory factor analysis with the first sample of participants, and (2) the confirmatory factor analysis with the second sample of participants. The purpose of the exploratory factor analysis was to reduce the length of the scale to the essential number of items. First, using SPSS Statistics 19 (SPSS Inc., 2009, Chicago, IL), a parallel analysis and Velicer’s minimum average partial (MAP) analysis identified the appropriate number of factors to extract [18]. Next, a principle component analysis was used, with an Oblimin rotation to facilitate interpretation of the extracted components, and separate the items into the subscales [19]. Using the pattern matrix, items with a loading of less than 0.8 on a factor, or a cross-loading between two or more factors of 0.3 or more, were eliminated. To evaluate if the items selected for each subscale were measuring the appropriate construct, a confirmatory factor analysis was then conducted on the second sample using MPlus 6.12 computer software (Muthen & Muthen, Los Angeles, CA). To account for the non-normality of the data, a maximum likelihood method with normal correction was utilized. Fit of the scale was evaluated using the traditional indices: chi square goodness of fit test (χ2); Root Mean Squared Error of Approximation (RMSEA); Standardized Root Mean Square error (SRMR); and Comparative Fit Index (CFI). The chi square goodness of fit test statistic determines if the model structure that is proposed is significantly different from the data that were collected. Although a nonsignificant chi square test is preferred, this is extremely difficult to meet with a large sample size as even minor differences between the tested model and the data will be detected as significant. As such, the additional indices of model fit were evaluated because they are less influenced by sample size. In general, it is agreed that a good fit has been obtained when RMSEA is equal to or less than 0.06 and SRMR is below 0.08, and for CFI, a good fit is indicated by values greater than 0.95 [20,21]. Cronbach’s alpha was used to examine internal consistency reliability of the inventory as a whole and for each subscale. In general, a Cronbach’s alpha greater than 0.70 is considered to be acceptable, while 0.80 and above is

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considered to be good [22,23]. Additional correlation and regression analyses were conducted on the resulting scale, the Blood Donation Fears Inventory (Appendix), to assess convergent and discriminant validity.

3.2. Assessment of reliability of the blood donation fears inventory

3. Results 3.1. Development of the blood donation fears inventory (BDFI) Using the first sample of participants, four factors were identified in the parallel analysis and MAP analysis. The items that comprise each subscale, and their factor loadings, are detailed in Table 1. Evaluation of items that comprised each factor through the principal component analysis identified the theme of each subscale. The first factor was comprised of items that reflected fears of the syncopal symptoms (e.g., dizziness and feeling faint) that could be experienced by donors during the donation process (Fear of Syncopal Symptoms subscale). The next factor was comprised of items that reflect specific fears of needles and having blood drawn (Fear of Blood and Needles subscale). The third factor consisted of items that represented fear of being evaluated by significant others if the donor experienced syncopal symptoms (Fear of Social Evaluation subscale). The final factor was comprised of items representing fear of receiving negative personal health news (Fear of Health Screen Results subscale). Next, the confirmatory factor analysis was conducted to examine the goodness of fit of a four-subscale model when applied to the second sample. Results of this analysis confirmed that the four-factor model provided a strong fit to the data in the second sample (χ2 (129) = 339.79, p < 0.001;

Table 1 Factor loadings for the retained items that comprise the Blood Donation Fears Inventory subscales. Subscale Syncopal symptoms Feeling dizzy after donating blood while at the blood drive Feeling dizzy after leaving the blood drive Feeling dizzy while donating blood Feeling weak after leaving the blood drive Feeling lightheaded after leaving the blood drive Feeling faint after donating blood while at the blood drive Feeling lightheaded after donating blood while at the blood drive Feeling faint while donating blood Feeling faint after leaving the blood drive Blood and needles Seeing a needle Having a needle in your arm Having blood drawn from your arm Social evaluation Feeling dizzy in front of people you know Feeling faint in front of people you know Feeling weak in front of people you know Feeling lightheaded in front of people you know Health screen results Discovering that you have a disease Learning that you are not as healthy as you thought

CFI = 0.972; RMSEA = 0.060; SRMR = 0.033). Figure 1 illustrates the factor loadings for each item as well as the correlations between the subscales.

Factor loading 0.91 0.90 0.88 0.88 0.84 0.83 0.82 0.82 0.80 0.89 0.84 0.83 –0.84 –0.83 –0.81 –0.81 0.94 0.86

To evaluate each subscale, the respective items were summed to create four subscale scores. To evaluate the BDFI full scale score, each subscale was averaged, and then the four subscales summed, to create the full scale score. This allowed for each subscale to be equally weighted in the total and thereby avoided a bias toward subscales with more items. To evaluate the internal consistency reliabilities, Cronbach’s alphas were computed for the full scale and the subscales with more than 2 items, and an intraclass correlation coefficient (ICC) was computed for the 2-item Fear of Health Screen Results subscale. These analyses indicated excellent reliability for the full scale (α = 0.97) and good to excellent internal consistency reliabilities for the subscales (Fear of Syncopal Symptoms: α = 0.98; Fear of Blood and Needles: α = 0.91; Fear of Social Evaluation: α = 0.95; Fear of Health Screen: ICC = 0.80). 3.3. Assessment of validity of the blood donation fears inventory To provide an initial assessment of discriminant and convergent validity, correlational analyses were conducted to examine the relationship between the BDFI subscales and the Blood and Needle subscales of the Medical Fears Survey. As can be seen in Table 2, the Medical Fears Survey subscales are positively correlated with the BDFI subscales (r between 0.34 and 0.86, all p < 0.001). Support for convergent validity of the BDFI is provided with the strongest correlations being between the Fear of Blood and Needles subscale of the BDFI and the Fear of Needles subscale of the MFS (r = 0.86). Discriminant validity is supported through the weaker correlations between the Fear of Health Screen Results subscale of the BDFI and the Fear of Needles subscale of the Medical Fears Survey (r = 0.45) and the Blood subscale of the Medical Fears Survey (r = 0.34), indicating that this particular subscale of the BDFI is contributing to the understanding of donor fears beyond the commonly used Medical Fears Survey subscales. Construct validity of the scale was examined by comparing BDFI scores among donors and non-donors in the sample, and as expected non-donors reported significantly more fear (M = 10.23, SD = 4.01) compared with donors (M = 7.76, SD = 2.93), t(453) = 7.36, p < 0.001. A similar pattern emerged when comparing non-donors and donors for the subscales, with non-donors scoring significantly higher on Fear of Syncopal Symptoms (M = 23.02, SD = 11.71, donors: M = 17.55, SD = 9.07, t(453) = 5.46, p < 0.001), Fear of Blood and Needles (M = 8.11, SD = 4.05, donors: M = 5.42, SD = 2.78, t(453) = 8.03, p < 0.001), Fear of Social Evaluation (M = 7.74, SD = 4.32, donors: M = 6.13, SD = 3.23, t(453) = 4.41, p < 0.001), and Fear of Health Screen Results (M = 6.09, SD = 2.39, donors: M = 4.94, SD = 2.27, t(453) = 5.22, p < 0.001). Potential differences between non-donors and donors were further examined by correlating subscale scores

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BDFI 1 0.94

BDFI 2 0.87

BDFI 3 0.95

BDFI 4 BDFI 5 BDFI 6

0.91 0.93 0.94 0.95

Fear of Syncopal Symptoms

0.69

Fear of Blood and Needles

0.82

BDFI 10

0.94

BDFI 11

0.87

BDFI 12

BDFI 7 0.95

BDFI 8

0.96

0.74

0.53

0.55

0.49

BDFI 9 BDFI 13

0.93 0.90

BDFI 14

Fear of Social Evaluation

Fear of Health Screen Results

0.48

0.77 0.87

BDFI 17 BDFI 18

0.88

BDFI 15 0.91

BDFI 16 Fig. 1. Model of confirmatory factor analysis of the subscales with correlations, and corresponding items with beta weights, for the Blood Donation Fears Inventory. Double-headed arrows indicate the correlations between the subscales. Single-headed arrows indicate the factor loadings for each item with its subscale.

Table 2 Convergent and discriminant validity analysis: Pearson correlations between the Blood Donation Fears Inventory subscales and Medical Fears Survey (MFS) subscales.

Syncopal Symptoms Blood and Needles Social Evaluation Health Screen Results MFS Fear of Needles MFS Fear of Blood

Syncopal symptoms

Blood and needles

Social evaluation

Health screen results

MFS fear of needles

MFS fear of blood

–

0.68* –

0.72* 0.53* –

0.47* 0.43* 0.41* –

0.65* 0.86* 0.54* 0.45* –

0.54* 0.63* 0.42* 0.34* 0.72* –

* p < 0.001.

with reported donation intention. As can be seen in Table 3, among non-donors all BDFI subscales and the full scale were significantly correlated with intention to donate with greater fear associated with lower intention to donate. Similar correlations were observed for donors, with the exception of a non-significant relationship between Fear of Health Screen Results and donation intention. A simple linear regression analysis indicated that as the total BDFI score increased, intention to donate significantly decreased, B = –0.40, t(453) = –9.24, p < 0.05, with fear accounting for 15.8% of the variability in intention to donate.

Table 3 Pearson correlations of the Blood Donation Fears Inventory subscales and full scale with Intention to Donate for non-donors and donors. Donation intention

Syncopal symptoms Blood and needles Social evaluation Health screen results Total * p < 0.01.

Non-donors

Donors

−0.26* −0.39* −0.17* −0.19* −0.32*

−0.31* −0.33* −0.20* −0.05 −0.28*

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4. Discussion The Blood Donation Fears Inventory (BDFI) provides a novel and valuable measure of donation-related fears that may be experienced by donors and non-donors alike. Results of our initial development testing reveal that the full scale BDFI and each of the four subscales met or exceeded the criteria for internal consistency, indicating that the BDFI is a reliable measure. Initial evidence of scale validity was also provided through the examination of how the BDFI related to other measures of fear, and the demonstration of expected group differences between donors and non-donors. While donation-related fear has been measured in prior research, such assessments have relied on more general measures of anxiety and fear of medical stimuli. In this regard, the BDFI makes a unique contribution by assessing fears that are not necessarily reflected in previous measures. For example, while most medical procedures are conducted in private, blood donation occurs in a social, public setting, with a variety of peers potentially present. The Medical Fears Survey was developed without public or social concerns in mind, as they would not be relevant. In contrast, the BDFI takes into account the public setting and the present findings demonstrate that fear of social evaluation following the experience of syncopal symptoms is an important concern for some young donors and non-donors. Another blood donation fear that emerged pertains to concerns about the health screen, which all potential donors must complete prior to donating blood. This finding is consistent with an earlier study using a single item assessment of this fear, which found it an important component within donation eligibility concerns when measuring the decision to donate [24]. Interestingly, in the present study this fear was related to negative donation intention among non-donors but not donors. This may be because individuals with a history of blood donation understand that they have already been screened, hence they are less likely to receive bad news following a subsequent donation. Alternatively, this relationship may be driven by non-donors who know or strongly believe that they would test positive for infectious disease. Recent research has provided greater recognition of the negative impact of fear and anxiety on donor recruitment and retention [4,5,9], as well as evidence that donor preparation materials can significantly attenuate donor anxiety [11,13–15,25]. For example, brochures, videos, and interactive web-sites that address donor fears and present empirically-supported coping options have been shown to reduce anxiety, enhance confidence, and increase donation intention [11,13–15,25]. However, because existing studies have not pre-screened respondents for fear and anxiety, existing donor preparation materials might prove to be even more helpful when provided specifically to those who score highly on the BDFI. If so, the BDFI may help blood centers to efficiently identify donors who would benefit most from pre-donation coping interventions. In addition to providing an overall score, the BDFI allows for the identification of specific fears held by potential donors that are unique to the blood donation context. Recent studies have demonstrated that a subset of experienced and first time donors report experiencing some fear prior to donation [7–9]; however, until now, the specific fears have not been mea-

sured in one comprehensive scale. The BDFI can be used both to ensure that diverse types of fear are considered and that interventions are tailored to address only those fears that are personally relevant to each donor, ultimately improving the donor’s experience. Although the present findings are encouraging, an important potential limitation is the fact that the instrument was developed in a relatively young sample. According to the most recent blood collection and utilization survey in the U.S., young donors account for a large proportion of all donations [26], and therefore a college-age population is a relevant and important group to study. However, future studies are needed to assess the psychometric properties of the BDFI among samples that are more diverse with respect to age and evaluate if the BDFI is a valid and reliable measure for older donors. Similarly, there was limited diversity in race and ethnicity for the participants, with the majority identifying as White. Future research should evaluate the BDFI’s validity and reliability to confirm its appropriateness for use with other racial and ethnic groups. Finally, this scale was developed using self-identified donors and non-donors at a Midwest U.S. college, and consistent with good assessment practices, if the BDFI is used in other countries, the psychometrics of the scale should be analyzed and reported. Authors statement of conflict of interest and adherence to ethical standards J.M. Kowalsky, C.R. France, J.L. France, E.A. Whitehouse, and L.K. Himawan certify that they have no conflicts of interest or financial involvement with this manuscript. All procedures, including the informed consent process, were approved by the Ohio University Institutional Review Board and conducted in accordance with the ethical standards of the Helsinki Declaration of 1975, as revised in 2000. Appendix: Blood donation fears inventory Directions: The following list includes some situations that will be encountered when donating blood, such as having a needle in your arm. Other situations may or may not be encountered, such as feeling dizzy. Using the scale below, please rate how you feel when considering each situation.

1. Feeling dizzy after donating blood while at the blood drive 2. Feeling dizzy after leaving the blood drive 3. Feeling dizzy while donating blood 4. Feeling weak after leaving the blood drive 5. Feeling lightheaded after leaving the blood drive 6. Feeling faint after donating blood while at the blood drive

1 = Not at all afraid or anxious 2 = Somewhat afraid or anxious 3 = Moderately afraid or anxious 4 = Very afraid or anxious 5 = Extremely afraid or anxious 1 2 3 4 5 1

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7. Feeling lightheaded after donating blood while at the blood drive 8. Feeling faint while donating blood 9. Feeling faint after leaving the blood drive 10. Seeing a needle 11. Having a needle in your arm 12. Having blood drawn from your arm 13. Feeling dizzy in front of people you know 14. Feeling faint in front of people you know 15. Feeling weak in front of people you know 16. Feeling lightheaded in front of people you know 17. Discovering that you have a disease 18. Learning that you are not as healthy as you thought

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Scoring: Fear of: – – – – –

Syncopal Symptoms = items 1 thru 9 Blood and Needles = items 10 thru12 Social Evaluation = items 13 thru 16 Health Screen Results = items 17 and 18 Total = Syncopal Symptoms/9 + Blood and Needles/ 3 + Social Evaluation/4 + Health Screen Results/2.

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[8] France CR, France JL, Himawan LK, Stephens KY, Frame-Brown TA, Venable GA, et al. How afraid are you of having blood drawn from your arm? A simple fear question predicts vasovagal reactions without causing them among high school donors. Transfusion 2013;53:315– 21. [9] France CR, France JL, Carlson BW, Himawan LK, Stephens KY, Frame-Brown TA, et al. Fear of blood draws, vasovagal reactions, and retention among high school donors. Transfusion 2014;54:918– 24. [10] Labus JS, France CR, Taylor BK. Vasovagal reactions in volunteer blood donors: analyzing the predictive power of the medical fears survey. Int J Behav Med 2000;7:62–72. [11] France CR, Montalva R, France JL, Trost Z. Enhancing attitudes and intentions in prospective blood donors: evaluation of a new donor recruitment brochure. Transfusion 2008;48:526–30. [12] France CR, Ditto B, Wissel ME, France JL, Dickert T, Rader A, et al. Predonation hydration and applied muscle tension combine to reduce presyncopal reactions to blood donation. Transfusion 2010;50:1257– 64. [13] France CR, France JL, Kowalsky JM, Cornett TL. Education in donation coping strategies encourages individuals to give blood: further evaluation of a new donor recruitment brochure. Transfusion 2010;50:85–91. [14] France CR, France JL, Wissel ME, Kowalsky JM, Bolinger EM, Huckins JL. Enhancing blood donation intentions using multimedia donor education materials. Transfusion 2011;51:1796–801. [15] France CR, France JL, Kowalsky JM, Copley DM, Lewis KN, Ellis GD, McGlone SM, Sinclair KS. A web-based approach to blood donor preparation. Transfusion 2013;53:328–36. [16] DeVellis RF. Classical test theory. Med Care 2006;44:50–9. [17] Bednall TC, Bove LL. Donating blood: a meta-analytic review of self-reported motivators and deterrents. Transfus Med Rev 2011;25:317–34. [18] O’Connor BP. SPSS and SAS programs for determining the number of components using parallel analysis and Velicer’s MAP test. Behav Res Method Instr Comp 2000;32:396–402. [19] Fabrigar LR, Wegener DT, MacCallum RC, Strahan EJ. Evaluating the use of exploratory factor analysis in psychological research. Psychol Method 1999;4:272–99. [20] Tabachnik BG, Fidell LS. Using multivariate statistics. 6th ed. New Jersey: Pearson Education Inc; 2013. [21] Hu L, Bentler PM. Cutoff criteria for fit indexes in covariance structure analysis: conventional criteria versus new alternatives. Struct Equation Model A Multidiscip J 1999;6:1–55. [22] Cortina JM. What is coefficient alpha? An examination of theory and applications. J Appl Psychol 1993;78:98–104. [23] Field A. Discovering Statistics using SPSS. 3rd ed. California: SAGE Publications, Inc.; 2009. [24] Burditt C, Robbins ML, Paiva A, Velicer WF, Koblin B, Kessler D. Motivation for blood donation among African Americans: developing measures for stage of change, decisional balance and self-efficacy constructs. J Behav Med 2009;32:429–42. [25] Masser BM, France CR. An evaluation of a donation coping brochure with Australian non-donors. Transfus Apher Sci 2010;43:291–7. [26] Report of the US Department of Health and Human Services. The 2011 national blood collection and utilization survey report. Washington, DC: US Department of Health and Human Services, Office of the Assistant Secretary for Health; 2013.