Addicrive Behaviors, Vol. 15, pp. 153-163, Printed in the USA. All rights reserved.
CRITERION-RELATED
1990 Copyright
0306-4603/90 $3.00 + .OO e 1990 Pergamon Press plc
VALIDITY OF THE ANORECTIC QUESTIONNAIRE
COGNITIONS
J. SCOTT MIZES Case Western Reserve University
School of Medicine
Abstract - Several authors have suggested core cognitive dysfunction as central to anorexia and bulimia nervosa. However, psychometrically sound assessment devices for these cognitions are notably lacking. Previous research with the Anorectic Cognitions Questionnaire (MAC) has suggested that it has good concurrent and criterion-related validity, and high internal consistency. As well, the factor structure has been supported. The purpose of this investigation was to further assess the criterion-related validity of the MAC. Male and female college students completed the MAC and a questionnaire about eating and weight-related behavior and attitudes in four areas: general emphasis on weight regulation, relative importance of specific benefits of losing or maintaining weight (i.e., psychological, appearance, and health benefits), use of calorie restriction strategies, and use of calorie burning strategies. In general, persons scoring above the mean on the MAC showed more evidence of pathological eating attitudes and behavior in all four areas.
Several authors have suggested that core cognitive dysfunction is central to the psychopathology of anorexia and bulimia nervosa. For example, Fairbum (1985) suggests that the pathological eating behavior of bulimics is understandable once it is appreciated that shape and weight are of fundamental psychological importance to these patients. Mizes (1985) posits a cognitive-behavioral model that suggests that excessive concerns about approval from others and basing self-worth on performance accomplishments are central to bulimia. For example, bulimics’ excessive emphasis on physical appearance and weight represents an attempt to excel at something to get the attention and approval of others, thereby compensating for low feelings of self-worth. Garner and Bemis (1982) have similarly emphasized cognitive factors in anorexia nervosa, suggesting three areas of faulty cognitions. First, eating disordered persons use weight and appearance as the sole or major determinant for judging their self-worth. Second, they evaluate self-worth in terms of their ability to show self-control of eating and weight. Thirdly, they fail to understand normal processes regarding eating and weight and thus attempt to tightly regulate food consumption and weight. Another cognitive perspective is offered by Polivy and Herman (1987), who describe the concept of “dietary restraint.” The model posits that chronic dieters (such as bulimics and anorexics) cognitively define food consumption limits to inhibit eating and produce weight loss. Counter-regulatory eating (i.e., binges) arises either from the real or perceived violation of the dietary boundary (i.e., having “blown it”) and/or weakening of eating self-control due to emotional distress. Dietary restraint has received a great deal of research attention. Several measures of dietary restraint have been developed, and there have been several laboratory studies investigating the effects of food pre-loads on counter-regulatory eating in restrained and unrestrained eaters (cf. Wardle & Beales, 1987). There have been fewer studies of dietary
Portions of this research were presented at the Society of Behavioral Medicine Convention, Boston, 1988. Thanks to Anne Farrell for her assistance with data analysis. Portions of this research were supported by a grant from the Geisinger Research Foundation. Requests for reprints should be sent to J. Scott Mizes, Ph.D., Dept. of Psychiatry, MetroHealth Medical Center, Case Western Reserve University School of Medicine, 3395 Scranton Rd., Cleveland, OH 44109. 153
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restraint in clinical eating disordered subjects (Johnson, Corrigan, Crusco, & Schlundt, 1986). Compared to dietary restraint, there has been suprisingly little research on other cognitive conceptualizations of eating disorders, such as those suggested by Garner and Bemis (1982). In part, this is due to the lack of validated assessment devices. Although several assessment devices exist, they have shortcomings. The Eating Attitudes Test (EAT, Garner & Garfinkel, 1979) has received much research attention, and its psychometric properties have been well supported. However, the EAT appears to better assess eating disorder symptoms rather than underlying cognitions. For example, sample items on the EAT include “Vomit after I have eaten, ” “Avoid foods with sugar in them,” and “Eat diet foods. ” There have been efforts to develop more cognitively oriented questionnaires such as the Bulimia Cognitive Distortions Scale (Schulman, Kinder, Powers, Prange, & Gleghom, 1986), and the Bulimic Thoughts Questionnaire (Phelan, 1987). While these scales may eventually prove useful, First, they were not specifically they suffer from one or more of three shortcomings. designed to assess the three cognitive domains suggested by Garner & Bemis (1982). Second, they also use items reflective of symptoms rather than cognitions (though to a lesser extent than the EAT). Lastly, their reliability and validity have not yet been firmly established. The lack of a well-validated instrument to assess eating disordered cognitions along the lines suggested by Garner and Bemis (1982) led to the development of the Anorectic Cognitions Questionnaire (MAC, Mizes & Klesges, 1989). The MAC is a 45item objective questionnaire that respondents rate on a 5point Likert scale, and is designed to assess cognitions relevant to both anorexia and bulimia nervosa. Initial research on the validity and reliability of the MAC has been encouraging. Mizes (1988), found that bulimics scored significantly higher on the MAC than did normals. Equally as important, the MAC accounted for 60% of the variance between the two groups. Thus, criterion-related validity in clinical groups was supported. The MAC was also shown to be correlated with several theoretically related dependent measures, such as measures of binge eating, body image distortion, and dieting. Thus, initial evidence of concurrent validity was shown. Mizes and Klesges (1989) conducted a factor analysis which empirically supported the three cognitive factors hypothesized by Garner and Bemis (1982). The criterion-related validity of the MAC was further supported by the finding, as predicted, of sex and relative weight status influences on MAC scores. Females scored significantly higher on the MAC, and underweight persons scored lower. A significant sex by relative weight interaction was also found. Additionally, the MAC was found to be correlated with measures of binge eating and body image distortion, as well as various measures of ideal weight, further supporting its concurrent validity. Finally, the overall scale and the specific subscales were found to be internally consistent, with a coefficient alpha of 0.91 for the total score. The purpose of the current investigation was to further examine the criterion-related validity of the MAC in a non-clinical sample. This was accomplished by comparing the self-reported eating and weight related behavior and attitudes of persons scoring high versus low on the MAC. A non-clinical sample was used on the assumption that the cognitions thought to be present in anorexia and bulimia differ from the normal population more quantitatively than qualitatively. This was based on the observation that maladaptive eating behavior is quite frequent even in so-called “normal” populations, especially for females (for example, see Klesges, Mizes, & Klesges, 1987). Thus, pathological cognitions should be present even in normal populations, though to a lesser degree. Therefore, it was decided that a logical progression in examining the criterion-related validity of the MAC was to assess its association with maladaptive eating behavior and attitudes in the normal population. Moreover, it was felt important to demonstrate that the MAC was sensitive to
Criterion-related
validity of the MAC
155
Table 1. Sample MAC subscale items Rigid weight regulation 1. If I don’t have a specific routine for my daily eating, 1’11lose all control and I’ll gain weight. 2. When I feel hungry, I can’t give into hunger. If I do I’ll never stop eating and I’ll soon be. fat. 3. If my weight goes up a couple of pounds, I don’t worry about it. It’s probably just temporary (due to water retention, for example), and eventually my weight will return to normal. Self-control
of eating and self-esteem
1. I feel victorious over my hunger when I am able to refuse sweets. 2. I am proud of myself when I control my urge to eat. 3. I feel guilty when I have eaten foods that I shouldn’t and exercising Appearance,
makes the guilt go away.
weight, and approval
1. How much I weigh has little to do with how popular I am. 2. My friends will like me regardless of how much I weigh. 3. People like you because of your personality, not whether you are overweight
or not.
pathological, though sub-clinical, eating behavior. This would help establish the MAC as potentially useful for longitudinal investigations of the initial development of eating disordered cognitions and subsequent emergence of clinical eating disorders. METHOD
The MAC includes items associated with rigid weight regulation, excessive self-control as the basis of self-esteem, and weight as a basis of approval. Sample items are shown in Table 1. The MAC was administered (in a group format) to 105 college males and 100 college females at a moderate sized midwestem state university. Their height and weight was determined on a balance beam scale accurate to l/4 lb. and l/4 in. Students participated to gain extra credit in their undergraduate psychology courses. All participants completed a semi-structured questionnaire’ on variety of eating and weight related behaviors and attitudes in four areas: general emphasis on weight regulation, importance of specific benefits for losing or maintaining weight (i.e., appearance, psychological, and health benefits), use of calorie restriction strategies, and use of calorie burning strategies. These variables were chosen due to their relevance to either subclinical eating pathology or clinical anorexia or bulimia nervosa. For example, Huenemann, Shapiro, Hampton, and Mitchell (1966) report nearly three-quarters of teenage girls expressed a strong desire to lose weight, although only 25% were overweight. Klesges et al. (1987) found that 89% of females and 54% of males had used some form of calorie restriction strategy in the preceding 6 months, and 80% of females and 46% of males reported using some strategy to increase energy expenditure. This was despite the fact that only 18% of the sample was obese. The diagnostic criteria for anorexia and bulimia nervosa (and associated features) note that persistent overconcern about weight, chronic dieting, and pathological strategies to avoid/ eliminate calories (purging, vigorous exercise) are crucial parts of the clinical picture (ARA, 1987). Thus, variables associated with overemphasis on weight, the psychological meaning of weight, dieting, and calorie expenditure were felt to be relevant criterion variables that should be related to measures of eating disordered cognitions. Regarding general emphasis on weight regulation, subjects indicated (yes/no) whether or not they had seriously attempted to lose weight in the previous 6 months, or if they had ‘Copies of the semi-structured the author.
questionnaire,
the MAC, and scoring procedures
for the MAC are available from
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J. SCOTT MIZES
seriously attempted to maintain their weight. On a l-9 scale (9 = high), subjects rated how important it was to achieve or maintain their ideal body weight. Subjects also stated their ideal weight. This self-ideal was then compared to the projected actual ideal weight, which was defined as the 50th percentile, based on DHEW (1979) age-, sex-, and height-adjusted norms. Subjects were asked to rate several indices of the relative importance of the benefits they saw to achieving or maintaining their ideal weight. The benefits were divided into health benefits (i.e., reduced risk of heart disease), appearance benefits (i.e., thinner hips), and psychological benefits (i.e., feel more confident about myself). After reading a brief description of these three areas, subjects rated the global importance of each area using a l-9 scale (9 = high). For each of the global benefits categories, subjects were asked to list in an open-ended fashion specific benefits that were important to them, and to rate the importance of each specific benefit on a l-9 scale. For example, one subject listed the following psychological benefits to maintaining/achieving ideal weight: “more confidence” (rated 6), “friends look up to you” (4), “better outlook on life” (7), “more sex appeal” (6), “more daring to try new experiences” (5), and “less trouble meeting new people” (6). The data were reviewed to develop classification categories and associated scoring criteria to characterize the range of specific benefits spontaneously listed by subjects (see Table 2 for category titles). The categories were rationally derived and arrived at by consensus of several raters. Five judges (who had assisted in development of scoring categories) received extensive training until they could score practice protocols to a criterion of 90% correct. Next the judges reviewed the open-ended responses and placed them into the various categories. Each subject’s responses were scored by two judges, and overall inter-rater agreement was 84%. For each specific benefit category, the number of times a subject listed that category was recorded. As well, the average importance rating for that category was recorded (if the subject did not list a particular category, a “0” was scored; if a category was listed once, the rating was scored; if the category was listed multiple times, the average of the ratings was recorded). For calorie restricting strategies, subjects were given a list of 27 specific strategies and asked to indicate if they had used the strategy anytime in the previous six months. In order to discern differences regarding intensity of use of a strategy, subjects were asked to indicate the number of times they attempted a strategy, the average duration of the attempt (in weeks), and the frequency the strategy was used per week. These numbers were then multiplied, resulting in an “intensity” figure. As an example, a person might indicate that they had 2 periods in the last 6 months where they fasted; that, on average, these fasting periods lasted 3 weeks; and that they typically fasted 4 days of the week. The resulting intensity figure would be 24. A similar approach was used for calorie burning strategies. Subjects were presented with a list of 23 strategies for increasing calories burned. Some strategies actually produce increased calorie expenditure (i.e., swimming, tennis), while others are popularly thought to contribute to calorie expenditure and weight loss even though in reality they do not (i.e., “cellulite” removal products, vibrating belts). As described above, an “intensity” value was determined. RESULTS
All analyses were conducted using a mean split procedure based on subjects’ MAC scores. For all subjects, the mean MAC score was 101.41, SD = 22.02. One hundred thirteen subjects scored below the mean, 92 above. High scorers on the MAC were compared to low
Criterion-related
Table 2. Specific benefits of weight loss or maintenance A. Psychological 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
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validity of the MAC
categories
benefits
Will be able to do physical activities better Will have improved self-concept Will have better moods overall Will have more confidence People will like me more Social relationships will improve Will feel better about my appearance Relationship with specific significant other will improve Will be better able to cope with life’s day-to-day tasks and problems Will feel more comfortable in sexual interactions Other
B. Appearance
benefits
1. Clothes will fit better 2. Can wear more attractive clothing 3. Specific body part will be thinner: Calves Buttocks Face Waist Chest kegs Other Thighs Al-lIlS 4. Will look better 5. Will be more attractive to opposite sex 6. Other C. Health benefits 1. 2. 3. 4. 5. 6. 7. 8. 9.
Reduce risk of heart attack Reduce risk of high blood pressure Reduce risk of other cardiovascular disorder Reduce risk of cancer Will be in better physical shape or condition Will generally feel better Will be less likely to get colds, flu, sickness Will be healthier and/or live longer Reduce risk of diabetes
using t tests, or Chi-Squares. Regarding general emphasis on weight regulation, more high MAC scorers (49.5%) than low MAC scorers (31.9%) worked to maintain their weight, F( 1, 202) = 6.66, p = .Oi I. Similarly, more high MAC (54.9%) than low MAC (21.2%) scorers actively attempted weightloss, F(1, 202) = 27.92,~ < .OOl. HighMACscorers (M = 7.19, SD = l.S)rated it as more important to achieve or maintain their ideal weight than did low MAC scorers (M = 6.15, SD = 1.8), t = 4.38, scorers
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Table 3. Specific psychological benefit/Mean importance endorsement frequencies
Benefit category Physical activities Self-concept Better moods More confidence Like me more Social life Like my looks Significant other Cope better Sex better Other
Low MAC Ratmg Frequency 1.2 3.3 1.1 2.0 1.9 2.2 2.0 .36 1.1 .14 1.2
(2.7) (3.9) (2.7) (3.3) (2.9)* (3.2)* (3.1) (1.6) (2.7) (1.1) (2.7)
.19 .52 .22 .34 .37 .46 .36 .05
(.43) (.67) c.56) i.56j (S9) (.78)* (.60) (.22) .17 (.42) .02 (. 13) .23 (.52)
ratings and
High MAC Ratmg Frequency .85 4.1 1.9 2.5 3.1 3.6 2.1 .66 1.5 0 1.6
(2.5) (4.0) (3.3) (3.8) (3.7)* (3.4)* (3.4) (2.3) (2.8) (0) (3.1)
.12 .62 .32 .33 .58 .87 .37 .11 .29 0 .36
(.36) (.66) (.55) (.49) (.74) (1.0)* (.74j (.41) (.62) (0) (.72)
Nofe. Numbers in parentheses are standard deviations. *p < .05 univariate test.
larger. Means and standard deviations for frequency and importance ratings of psychological benefits are presented in Table 3. Regarding the global rating of the importance of appearance benefits, high MAC scorers (M = 7.6, SD = 2.7) rated it higher than did low MAC scorers (M = 6.9, SD = 2.4), F( 1, 192) = 4.2, p = .04. For the specific appearance benefits, a MANOVA on the frequency of category endorsement was significant, Wilks’ lambda = .88, F(14, 188) = 1.9, p = .03. Univariate tests were significant for “clothing will fit better” (p = .Ol), “legs will be thinner” 0, = .05), and “will be more attractive to opposite sex” @ = .Ol), with high MAC scorers ratings being higher. On the mean ratings of appearance benefits, the MANOVA was also significant, Wilks’ lambda = .87, F(14, 188) = 2.1, p = .02. Univariate tests were significant for “clothing will fit better” @ = .004), “legs will be thinner” (p = .04), “thinner other” (p = .OS), and “more attractive to opposite sex” (JI = .03), with high MAC scorers ratings being larger. Means and standard deviations for frequency and importance ratings for appearance benefits are presented in Table 4. For the global rating of health benefits, a significant difference between high MAC scorers (M = 7.2, SD = 3.5) and low MAC scorers (M = 7.1, SD = 3.2) was not found, F(l, 192) = 1.1, p = .3. A MANOVA on the frequency of specific health benefits was not significant, Wilks’ lambda = .97, F(l0, 192) = .5, p = .9. Similarly, a MANOVA on mean ratings was not significant, Wilks’ lambda = .95, F(10, 192) = .9, p = .5. For the calorie restriction and burning strategies, individual t tests were conducted on the intensity scores. A MANOVA was not conducted due to the low number of subjects relative to the number of variables (Tabachnick & Fidell, 1983). On variables that had zeros in one cell, thereby precluding use of a t test, a Chi square was conducted on a yes/no frequency of strategy usage. For the calorie restriction strategies, 9 of the 27 strategies (13 including trends) were significantly different (see Table 5). Specifically, high MAC scorers had significantly higher intensity scores on “generally eat less” (p = .05), “fasting” @ = .02), “specific daily calorie limit” 0, = .04), “formal weight loss program” (p = .05), “high protein diet” @ = .03), “avoiding places where food is available” @ = .004), “eating at a consistent place or time” @ = .03), “self-reward for making daily calorie limit” @ = .Ol), and “eat only in kitchen or dining room” @ = .04). Trends were observed for “skipping meals” @ =
Criterion-related
validity of the MAC
159
Table 4. Specific appearance benefitMean importance endorsement frequencies
Benefit category Cloths fit Nicer clothes Thinner face Chest AllllS
waist Buttocks kegs Thighs Calves Other
Low MAC Ratmg Frequency 2.9 1.4 1.6 .13 .28 3.0 1.1 .34 1.2 .20 .35
(3.4) (2.6)* (2.8) (1.0) (1.3) (3.5) (2.7) (1.5)* (2.6) (1.2) (1.6)*
.49 .24 .29 .02 .06 .50 .14 .06 .18 .03
(.6Q) (.45)* (.53) (.13) (.24) (60) (.35) (.24)* (.38) (.16)
ratings and
High MAC Frequency
Ratmg 3.8 2.8 1.8 .41 .64 3.5 1.1 1.2 1.9 .15
(3.9) (3.6)* (3.1) (1.7) (2.0) (3.8) (2.7) (2.7)* (3.5) (1.0)
.65 .50 .30 .07 .ll .57 .15
(.72) (.75)* (.49) (.25) (.31) (.63) (.36) .19 (.42)* .25 (.44) .02 (.15)
.12
*p < .05 univariate test.
.lO), “weight control pills” @ = .OS), “serve meal on one plate” (p = .07), and “serve smaller portions” (p = .lO). For the calorie burning strategies, 5 of 23 strategies (7 counting trends) were significantly different, with high MAC scorers having higher intensity scores than low MAC scorers (see Table 6). Specifically, differences were found on “movie star exercise program” @ = .OS), “dance class or dancing” @ = .04), “gymnastics” (p = .Ol), “sit-ups, chin-ups, push-ups” @ = .Ol), and “ate foods to increase metabolic rate” @ = .Ol). Trends were observed for “jazzercise” @ = .08) and “jump rope” (p = .lO). DISCUSSION The MAC was developed to empirically assess cognitions thought to be related to anorexia and bulimia nervosa. Previous studies have supported the MAC’s criterion related validity, concurrent validity, factor structure, and internal consistency. Results of the current investigation further support the criterion-related validity of the MAC, and show that it is sensitive to subclinical differences in eating-related behavior and attitudes. In general, persons scoring high on the MAC showed more emphasis on weight regulation, placed greater emphasis on the psychological and appearance benefits of achieving or maintaining an ideal weight, used more calorie restriction strategies, and to a lesser extent, used more calorie burning strategies. Regarding emphasis on weight regulation, high MAC scorers had more frequently been involved in active attempts to maintain or lose weight in the previous six months, and rated it as more important to achieve or maintain their ideal weight. They also had a larger discrepancy between a DHEW ideal weight and their self-ideal weight, showing an endorsement of biologically unrealistic low weights. For the benefits of achieving or maintaining ideal weight, high MAC scorers showed strong endorsement of the importance of the psychological benefits of ideal weight, as evidenced by a global rating of importance. On an open-ended listing and importance rating of specific psychological benefits, high MAC scorers indicated greater endorsement of the
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Table 5. Calorie burning strategy intensify scores Strategy Running, jogging Swimming Bicycling Movie star exercise program** Richard Simmons’ exercise program Weight Lifting Jazzercise* Dance class or dancing** Jump rope* Tennis Walking Racquetball/squash Basketball Gymnastics** Sauna or steam bath Plastic pants or belts Increase routine exercise Self-reward for exercise Cellulite removal” Vibrating belts/rollers” Sit-ups, chin-ups, push-ups** Foods to increase metabolic rate** Othef
Low MAC 98.3 13.9 17.0 0.9 1.5 66.7 0.5 3.0 2.0 3.6 31.9 13.5 15.7 0.2 3.5 2.1 41.8 1.1 0 0 23.2 0.2 0
(681.1) (46.6) (40.0) (3.6) (8.7) (455.9) (2.8) (9.5) (11.6) (11.7) (70.1) (76.2) (86.9) (1.7) (15.8) (15.6) (206.9) (9.6) (0) (0) (43.4) (1.4)
Note. Numbers in parentheses are standard deviations. “Chi-square conducted due to no variance in 1 group, strategy. *p < .lO. **p < .05.
High MAC 39.3 22.1 44.0 5.0 2.1 13.5 2.2 8.9 6.2 3.5 33.8 5.4 39.5 2.5 6.8 1.3 63.0 1.9 1.2 1.1 43.6 7.7 15
(93.9) (78.9) (195.3) (22.1) (10.5) (35.5) (10.1) (27.5) (23.7) (11.0) (70.1) (28.9) (196.3) (9.5) (20.0) (9.6) (197.1) (12.0) (8.9) (10.0) (71.6) (36.2) (140.9)
data recorded
f statistic 0.8 0.9 1.4 1.9 0.4 1.1 1.8 2.1 1.7 0.1 0.2 1.0 1.2 2.5 1.3 0.4 0.7 0.5 2.2 0.8 2.5 2.2 1.9
as yes/no on use of
belief that ideal weight would result in people liking them more and in improvements in their social life. While several other potential particular benefits of ideal weight were listed, it is interesting that these beliefs were two of the most frequently occurring. These two categories would be expected to be highly related to the MAC given the presence of the “weight and eating behavior as the basis of approval” factor. For the appearance benefits of ideal weight, high MAC scorers showed a higher global endorsement of this belief. For the specific appearance benefits, high MAC scorers indicated greater endorsement of being able to wear nicer clothes that fit better, of having thinner legs, and of being more attractive to the opposite sex. Again, the emphasis on approval from others is noted. It is interesting that simply “looking better” did not discriminate high and low MAC scorers, but being attractive did. This would suggest physical attractiveness per se is not the issue, but rather physical attractiveness as the basis of approval from others. This distinction is consistent with the construction of the items for the “approval” subscale of the MAC. In addition, the distinction is consistent with theorizing about the specific nature of the pathological emphasis on weight and appearance. That is, it is one thing to want to look nice, it is quite another to see appearance as a major mechanism for gaining approval and self-esteem. High and low MAC scorers did not differ on the importance of health benefits, either for the global rating or for specific benefits. Theoretically, this could be predicted since the pathological attitudes that the MAC is designed to assess has little to do with health issues relevant to weight. Rather, the focus is on psychological and social variables. The data on weight benefits are particularly useful because of the manner in which they
Criterion-related
validity of the MAC
Table 6. Calorie restriction Strategy Generally eat less** Fasting** Scarsdale diet” Weight Watchers diet Skipping meals* Stillman’s Water diet Diabetic Food Exchange” Specific daily calorie limit** Eliminate/reduce sweets Self-induced vomiting Laxative? Diuretics Weight control pills* Starch blockers” Grapefruit diet Formal weight loss program**a High fiber diet Smoke or drink caffeine High protein diet**’ Avoid food places** Consistent eating place/time** Limit “forbidden food” access Self-reward /self-monitor food intake** Serve 1 plate of food* Serve smaller portions* Serve food on smaller plates Eat only in kitchen**
161
strategy intensity scores Low MAC
42.8 0.2 0 0 27.9 0 0 3.3 37.9 0.0
(87.0) (1.4) (0) (0) (127.0) (0) (0) (17.3) (145.3) (0.1)
0 (0) 0.1 2.8 0.2 0.2 0.7 42.6 0 2.6 4.7 23.8 0.4 0.2 15.2 2.6 5.5
(0.9) (14.7) (2.6) (1.2)
io, (6.8)
(328.2) (0) (11.5) (26.2) (123.0) (2.9) (2.0) (65.5) (17.9) (25.4)
Note. Numbers in parentheses are standard deviations. “Chi-square conducted due to no variance in 1 group, strategy. *p < .lO. **p < .05.
High MAC 90.5 3.8 0.5 0
t statistic
(237.3) (15.7) (3.3) (0)
2.0 2.4 1.5 -
88.5 (362.7) 0 (0)
1.7 -
5.7 (47.0) 13.5 (48.6) 34.7 (57.8) 3.0 (23.5) 1.6 (13.2) 1.5 (13.2) 9.1 (34.5) 0 (0) 1.9 (17.5) 3.4 (15.9) 2.9 (26.1) 17.7 (45.4) 5.4 (41.9) 27.1 (87.8) 18.1 (55.7) 38.0 (89.3) 4.7 (17.1) 11 .O (62.5) 31.7 (78.3) 4.6 (15.2) 14.9 (40.1)
1.5 2.1 0.2 0.2 1.5 1.2 1.8 0 1.0 3.8 0.9 0.7 4.8 2.9 2.2 0.9 2.6 1.8 1.6 .9 7.1
data recorded
as yes/no on use of
are collected. Because subjects did not respond to objective questionnaires in addition to the MAC, the likelihood of method error variance is reduced. Also, by allowing subjects to list freely the benefits they found important, we have a much better idea of what the population of relevant weight benefits are in the normal population. This allows greater confidence in the validity of any associations observed with MAC scores. Persons scoring higher on the MAC showed a greater tendency to be involved in a variety of calorie restricting activities. These included generally eating less, fasting, having a specific daily calorie limit, using weight control pills, participating in a weight loss program, going on a high protein diet, and self-rewarding for staying within a daily calorie limit. Also included were a variety of stimulus control strategies such as avoiding places where food is available, having a consistent eating place or time, serving only one plate of food, serving smaller portions, and eating only in the kitchen. While not statistically significant, data for a few particularly pathological low frequency behaviors were notable. Laxative abuse was endorsed by three high MAC scorers, but none of the low MAC scorers. Self-induced vomiting was reported by six high MAC scorers, but only one low MAC scorer. Persons scoring higher on the MAC showed some tendency to be engaged in more exercise or other calorie burning activities. Specifically, high MAC scorers were more likely to use a movie star’s exercise program (such as the Jane Fonda workout), participate in jazzercise, dance class or dancing, gymnastics, jumping rope, calisthenics such as sit-ups, chin-ups, and
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push-ups, and to eat foods presumed to increase metabolic rate. While several physical activities did not discriminate high and low MAC scorers, an interesting pattern emerged. Activities associated with recreation or health (i.e., swimming, running, tennis) did not differ, while those associated with improving appearance (Jane Fonda workout, dance class) did show differences. Also, consistent with sex-role expectations regarding the importance of appearance, the discriminating activities were those that women tend to engage in for appearance reasons. While the data for the calorie restriction and calorie burning strategies support the validity of the MAC, it is important to note that these data are retrospective self-reports and subject to the limitations of accurate recall. This is less of a concern for a simple indication of whether a strategy was used or not, more so for the “intensity” of use. While recognizing this limitation, this self-report assessment was felt to be a practical compromise between obtaining the potentially more sensitive measure of intensity of strategy use versus the sizeable problem of following 200 people over 6 months and accurately logging their calorie burning and restriction activities. Also, the large number of statistical tests for the calorie restriction and calorie burning strategies raises the possibility of Type I error. This is less of a concern for the calorie restriction strategies because several significant effects were found. However, fewer significant effects were found for calorie burning strategies, so these results should be viewed more conservatively. Overall, the findings of the current study support the criterion-related validity and sensitivity of the MAC, adding to the growing research supporting the psychometric characteristics of the questionnaire. As the MAC’s utility is hopefully supported, it may serve a valuable role as a valid and reliable measure of presumed eating disordered cognitions. This will allow research on the role of cognitions in anorexia and bulimia to proceed from a firmer empirical base. As well, the MAC may eventually become a useful clinical tool.
REFERENCES American Psychiatric Association. (1987). Diagnostic and statistical manual of mental disorders (3rd ed. rev.). Washington, DC: Author. Department of Health, Education, and Welfare. (1979). Weight by height and age for adults 18-74 years: U.S. 1971-1974 (DHEW Publication No. 79-1656. Series 11. No. 280). Bethesda, MD: Author. Fairbum, C.G. (1985). A cognitive behavioral treatment of bulimia. in D.M. Garner, & P.E. Gartinkel (Eds.), Handbook ojpsychotherapy for anorexia nervosa and bulimia (pp. 160-192). New York: Guilford Press. Garner, D.M., & Bemis, K.M. (1982). A cognitive behavioral approach to anorexia nervosa. Cognitive Therapy and Research, 6, 123-150. Garner, D.M., & Garfinkel, P.E. (1979). The Eating Attitudes Test: An index of the symptoms of anorexia nervosa. Psychological Medicine, 9, 273-279. Huenemann, R.L., Shapiro, L.R., Hampton, M.C.. & Mitchell, B.W. (1966). A longitudinal study of gross body composition and body conformation and their association with food and activity in a teenage population. American Journal of Clinical Nutrition, 18, 325-338. Johnson, W.G., Corrigan, S.A., Crusco, A.H., & Schlundt, D.G. (1986). Restraint among bulimic women. Addictive Behaviors, 11, 351-354. Klesges, R.C., Mizes, J.S., & Klesges, L.M. (1987). Self-help dieting strategies in college males and females. International Journal of Eating Disorders, 6, 409-417. Mizes, J.S. (1985). Bulimia: A review of its symptomatology and treatment. Advances in Behavior Research and Therapy, 7, 91-142. Mizes, J.S. (1988). Personality characteristics of bulimic and non-eating disordered female controls: A cognitive behavioral perspective. International Journal of Eating Disorders, 7, 541-550. Mixes, J.S., & Klesges, R.C. (1989). Validity, reliability, and factor structure of the Anorectic Cognitions Questionnaire. Addictive Behaviors, 14, 589-594. Phelan, P.W. (1987). Cognitive correlates of bulimia: The Bulimic Thoughts Questionnaire. lmernational Journal of Eating Disorders, 6, 59347. Polivy, J., & Herman, C.P. (1987). Diagnosis and treatment of normal eating. Journal Consultingand Clinical Psychology, 42, 635&M.
of
Criterion-related
validity of the MAC
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Schulman, R.G., Kinder, B.N., Powers, P.S., Prange, M., & Gleghorn, A. (1986). The development of a scale to measure cognitive distortions in bulimia. Jourd of PersonalityAssessment, 50, 630439. Tabachnick, B.G., & Fidell, L. (1983). Using multivariate statistics. New York: Harper $ Row. Wardle, J., & Beales, S. (1987). Restraint and food intake: An experimental study of eating patterns in the laboratory and in normal life. Behavior Research Therapy, 25, 179-185.
CRITERION-RELATED
1990 Copyright
0306-4603/90 $3.00 + .OO e 1990 Pergamon Press plc
VALIDITY OF THE ANORECTIC QUESTIONNAIRE
COGNITIONS
J. SCOTT MIZES Case Western Reserve University
School of Medicine
Abstract - Several authors have suggested core cognitive dysfunction as central to anorexia and bulimia nervosa. However, psychometrically sound assessment devices for these cognitions are notably lacking. Previous research with the Anorectic Cognitions Questionnaire (MAC) has suggested that it has good concurrent and criterion-related validity, and high internal consistency. As well, the factor structure has been supported. The purpose of this investigation was to further assess the criterion-related validity of the MAC. Male and female college students completed the MAC and a questionnaire about eating and weight-related behavior and attitudes in four areas: general emphasis on weight regulation, relative importance of specific benefits of losing or maintaining weight (i.e., psychological, appearance, and health benefits), use of calorie restriction strategies, and use of calorie burning strategies. In general, persons scoring above the mean on the MAC showed more evidence of pathological eating attitudes and behavior in all four areas.
Several authors have suggested that core cognitive dysfunction is central to the psychopathology of anorexia and bulimia nervosa. For example, Fairbum (1985) suggests that the pathological eating behavior of bulimics is understandable once it is appreciated that shape and weight are of fundamental psychological importance to these patients. Mizes (1985) posits a cognitive-behavioral model that suggests that excessive concerns about approval from others and basing self-worth on performance accomplishments are central to bulimia. For example, bulimics’ excessive emphasis on physical appearance and weight represents an attempt to excel at something to get the attention and approval of others, thereby compensating for low feelings of self-worth. Garner and Bemis (1982) have similarly emphasized cognitive factors in anorexia nervosa, suggesting three areas of faulty cognitions. First, eating disordered persons use weight and appearance as the sole or major determinant for judging their self-worth. Second, they evaluate self-worth in terms of their ability to show self-control of eating and weight. Thirdly, they fail to understand normal processes regarding eating and weight and thus attempt to tightly regulate food consumption and weight. Another cognitive perspective is offered by Polivy and Herman (1987), who describe the concept of “dietary restraint.” The model posits that chronic dieters (such as bulimics and anorexics) cognitively define food consumption limits to inhibit eating and produce weight loss. Counter-regulatory eating (i.e., binges) arises either from the real or perceived violation of the dietary boundary (i.e., having “blown it”) and/or weakening of eating self-control due to emotional distress. Dietary restraint has received a great deal of research attention. Several measures of dietary restraint have been developed, and there have been several laboratory studies investigating the effects of food pre-loads on counter-regulatory eating in restrained and unrestrained eaters (cf. Wardle & Beales, 1987). There have been fewer studies of dietary
Portions of this research were presented at the Society of Behavioral Medicine Convention, Boston, 1988. Thanks to Anne Farrell for her assistance with data analysis. Portions of this research were supported by a grant from the Geisinger Research Foundation. Requests for reprints should be sent to J. Scott Mizes, Ph.D., Dept. of Psychiatry, MetroHealth Medical Center, Case Western Reserve University School of Medicine, 3395 Scranton Rd., Cleveland, OH 44109. 153
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restraint in clinical eating disordered subjects (Johnson, Corrigan, Crusco, & Schlundt, 1986). Compared to dietary restraint, there has been suprisingly little research on other cognitive conceptualizations of eating disorders, such as those suggested by Garner and Bemis (1982). In part, this is due to the lack of validated assessment devices. Although several assessment devices exist, they have shortcomings. The Eating Attitudes Test (EAT, Garner & Garfinkel, 1979) has received much research attention, and its psychometric properties have been well supported. However, the EAT appears to better assess eating disorder symptoms rather than underlying cognitions. For example, sample items on the EAT include “Vomit after I have eaten, ” “Avoid foods with sugar in them,” and “Eat diet foods. ” There have been efforts to develop more cognitively oriented questionnaires such as the Bulimia Cognitive Distortions Scale (Schulman, Kinder, Powers, Prange, & Gleghom, 1986), and the Bulimic Thoughts Questionnaire (Phelan, 1987). While these scales may eventually prove useful, First, they were not specifically they suffer from one or more of three shortcomings. designed to assess the three cognitive domains suggested by Garner & Bemis (1982). Second, they also use items reflective of symptoms rather than cognitions (though to a lesser extent than the EAT). Lastly, their reliability and validity have not yet been firmly established. The lack of a well-validated instrument to assess eating disordered cognitions along the lines suggested by Garner and Bemis (1982) led to the development of the Anorectic Cognitions Questionnaire (MAC, Mizes & Klesges, 1989). The MAC is a 45item objective questionnaire that respondents rate on a 5point Likert scale, and is designed to assess cognitions relevant to both anorexia and bulimia nervosa. Initial research on the validity and reliability of the MAC has been encouraging. Mizes (1988), found that bulimics scored significantly higher on the MAC than did normals. Equally as important, the MAC accounted for 60% of the variance between the two groups. Thus, criterion-related validity in clinical groups was supported. The MAC was also shown to be correlated with several theoretically related dependent measures, such as measures of binge eating, body image distortion, and dieting. Thus, initial evidence of concurrent validity was shown. Mizes and Klesges (1989) conducted a factor analysis which empirically supported the three cognitive factors hypothesized by Garner and Bemis (1982). The criterion-related validity of the MAC was further supported by the finding, as predicted, of sex and relative weight status influences on MAC scores. Females scored significantly higher on the MAC, and underweight persons scored lower. A significant sex by relative weight interaction was also found. Additionally, the MAC was found to be correlated with measures of binge eating and body image distortion, as well as various measures of ideal weight, further supporting its concurrent validity. Finally, the overall scale and the specific subscales were found to be internally consistent, with a coefficient alpha of 0.91 for the total score. The purpose of the current investigation was to further examine the criterion-related validity of the MAC in a non-clinical sample. This was accomplished by comparing the self-reported eating and weight related behavior and attitudes of persons scoring high versus low on the MAC. A non-clinical sample was used on the assumption that the cognitions thought to be present in anorexia and bulimia differ from the normal population more quantitatively than qualitatively. This was based on the observation that maladaptive eating behavior is quite frequent even in so-called “normal” populations, especially for females (for example, see Klesges, Mizes, & Klesges, 1987). Thus, pathological cognitions should be present even in normal populations, though to a lesser degree. Therefore, it was decided that a logical progression in examining the criterion-related validity of the MAC was to assess its association with maladaptive eating behavior and attitudes in the normal population. Moreover, it was felt important to demonstrate that the MAC was sensitive to
Criterion-related
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155
Table 1. Sample MAC subscale items Rigid weight regulation 1. If I don’t have a specific routine for my daily eating, 1’11lose all control and I’ll gain weight. 2. When I feel hungry, I can’t give into hunger. If I do I’ll never stop eating and I’ll soon be. fat. 3. If my weight goes up a couple of pounds, I don’t worry about it. It’s probably just temporary (due to water retention, for example), and eventually my weight will return to normal. Self-control
of eating and self-esteem
1. I feel victorious over my hunger when I am able to refuse sweets. 2. I am proud of myself when I control my urge to eat. 3. I feel guilty when I have eaten foods that I shouldn’t and exercising Appearance,
makes the guilt go away.
weight, and approval
1. How much I weigh has little to do with how popular I am. 2. My friends will like me regardless of how much I weigh. 3. People like you because of your personality, not whether you are overweight
or not.
pathological, though sub-clinical, eating behavior. This would help establish the MAC as potentially useful for longitudinal investigations of the initial development of eating disordered cognitions and subsequent emergence of clinical eating disorders. METHOD
The MAC includes items associated with rigid weight regulation, excessive self-control as the basis of self-esteem, and weight as a basis of approval. Sample items are shown in Table 1. The MAC was administered (in a group format) to 105 college males and 100 college females at a moderate sized midwestem state university. Their height and weight was determined on a balance beam scale accurate to l/4 lb. and l/4 in. Students participated to gain extra credit in their undergraduate psychology courses. All participants completed a semi-structured questionnaire’ on variety of eating and weight related behaviors and attitudes in four areas: general emphasis on weight regulation, importance of specific benefits for losing or maintaining weight (i.e., appearance, psychological, and health benefits), use of calorie restriction strategies, and use of calorie burning strategies. These variables were chosen due to their relevance to either subclinical eating pathology or clinical anorexia or bulimia nervosa. For example, Huenemann, Shapiro, Hampton, and Mitchell (1966) report nearly three-quarters of teenage girls expressed a strong desire to lose weight, although only 25% were overweight. Klesges et al. (1987) found that 89% of females and 54% of males had used some form of calorie restriction strategy in the preceding 6 months, and 80% of females and 46% of males reported using some strategy to increase energy expenditure. This was despite the fact that only 18% of the sample was obese. The diagnostic criteria for anorexia and bulimia nervosa (and associated features) note that persistent overconcern about weight, chronic dieting, and pathological strategies to avoid/ eliminate calories (purging, vigorous exercise) are crucial parts of the clinical picture (ARA, 1987). Thus, variables associated with overemphasis on weight, the psychological meaning of weight, dieting, and calorie expenditure were felt to be relevant criterion variables that should be related to measures of eating disordered cognitions. Regarding general emphasis on weight regulation, subjects indicated (yes/no) whether or not they had seriously attempted to lose weight in the previous 6 months, or if they had ‘Copies of the semi-structured the author.
questionnaire,
the MAC, and scoring procedures
for the MAC are available from
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seriously attempted to maintain their weight. On a l-9 scale (9 = high), subjects rated how important it was to achieve or maintain their ideal body weight. Subjects also stated their ideal weight. This self-ideal was then compared to the projected actual ideal weight, which was defined as the 50th percentile, based on DHEW (1979) age-, sex-, and height-adjusted norms. Subjects were asked to rate several indices of the relative importance of the benefits they saw to achieving or maintaining their ideal weight. The benefits were divided into health benefits (i.e., reduced risk of heart disease), appearance benefits (i.e., thinner hips), and psychological benefits (i.e., feel more confident about myself). After reading a brief description of these three areas, subjects rated the global importance of each area using a l-9 scale (9 = high). For each of the global benefits categories, subjects were asked to list in an open-ended fashion specific benefits that were important to them, and to rate the importance of each specific benefit on a l-9 scale. For example, one subject listed the following psychological benefits to maintaining/achieving ideal weight: “more confidence” (rated 6), “friends look up to you” (4), “better outlook on life” (7), “more sex appeal” (6), “more daring to try new experiences” (5), and “less trouble meeting new people” (6). The data were reviewed to develop classification categories and associated scoring criteria to characterize the range of specific benefits spontaneously listed by subjects (see Table 2 for category titles). The categories were rationally derived and arrived at by consensus of several raters. Five judges (who had assisted in development of scoring categories) received extensive training until they could score practice protocols to a criterion of 90% correct. Next the judges reviewed the open-ended responses and placed them into the various categories. Each subject’s responses were scored by two judges, and overall inter-rater agreement was 84%. For each specific benefit category, the number of times a subject listed that category was recorded. As well, the average importance rating for that category was recorded (if the subject did not list a particular category, a “0” was scored; if a category was listed once, the rating was scored; if the category was listed multiple times, the average of the ratings was recorded). For calorie restricting strategies, subjects were given a list of 27 specific strategies and asked to indicate if they had used the strategy anytime in the previous six months. In order to discern differences regarding intensity of use of a strategy, subjects were asked to indicate the number of times they attempted a strategy, the average duration of the attempt (in weeks), and the frequency the strategy was used per week. These numbers were then multiplied, resulting in an “intensity” figure. As an example, a person might indicate that they had 2 periods in the last 6 months where they fasted; that, on average, these fasting periods lasted 3 weeks; and that they typically fasted 4 days of the week. The resulting intensity figure would be 24. A similar approach was used for calorie burning strategies. Subjects were presented with a list of 23 strategies for increasing calories burned. Some strategies actually produce increased calorie expenditure (i.e., swimming, tennis), while others are popularly thought to contribute to calorie expenditure and weight loss even though in reality they do not (i.e., “cellulite” removal products, vibrating belts). As described above, an “intensity” value was determined. RESULTS
All analyses were conducted using a mean split procedure based on subjects’ MAC scores. For all subjects, the mean MAC score was 101.41, SD = 22.02. One hundred thirteen subjects scored below the mean, 92 above. High scorers on the MAC were compared to low
Criterion-related
Table 2. Specific benefits of weight loss or maintenance A. Psychological 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.
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validity of the MAC
categories
benefits
Will be able to do physical activities better Will have improved self-concept Will have better moods overall Will have more confidence People will like me more Social relationships will improve Will feel better about my appearance Relationship with specific significant other will improve Will be better able to cope with life’s day-to-day tasks and problems Will feel more comfortable in sexual interactions Other
B. Appearance
benefits
1. Clothes will fit better 2. Can wear more attractive clothing 3. Specific body part will be thinner: Calves Buttocks Face Waist Chest kegs Other Thighs Al-lIlS 4. Will look better 5. Will be more attractive to opposite sex 6. Other C. Health benefits 1. 2. 3. 4. 5. 6. 7. 8. 9.
Reduce risk of heart attack Reduce risk of high blood pressure Reduce risk of other cardiovascular disorder Reduce risk of cancer Will be in better physical shape or condition Will generally feel better Will be less likely to get colds, flu, sickness Will be healthier and/or live longer Reduce risk of diabetes
using t tests, or Chi-Squares. Regarding general emphasis on weight regulation, more high MAC scorers (49.5%) than low MAC scorers (31.9%) worked to maintain their weight, F( 1, 202) = 6.66, p = .Oi I. Similarly, more high MAC (54.9%) than low MAC (21.2%) scorers actively attempted weightloss, F(1, 202) = 27.92,~ < .OOl. HighMACscorers (M = 7.19, SD = l.S)rated it as more important to achieve or maintain their ideal weight than did low MAC scorers (M = 6.15, SD = 1.8), t = 4.38, scorers
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MIZES
Table 3. Specific psychological benefit/Mean importance endorsement frequencies
Benefit category Physical activities Self-concept Better moods More confidence Like me more Social life Like my looks Significant other Cope better Sex better Other
Low MAC Ratmg Frequency 1.2 3.3 1.1 2.0 1.9 2.2 2.0 .36 1.1 .14 1.2
(2.7) (3.9) (2.7) (3.3) (2.9)* (3.2)* (3.1) (1.6) (2.7) (1.1) (2.7)
.19 .52 .22 .34 .37 .46 .36 .05
(.43) (.67) c.56) i.56j (S9) (.78)* (.60) (.22) .17 (.42) .02 (. 13) .23 (.52)
ratings and
High MAC Ratmg Frequency .85 4.1 1.9 2.5 3.1 3.6 2.1 .66 1.5 0 1.6
(2.5) (4.0) (3.3) (3.8) (3.7)* (3.4)* (3.4) (2.3) (2.8) (0) (3.1)
.12 .62 .32 .33 .58 .87 .37 .11 .29 0 .36
(.36) (.66) (.55) (.49) (.74) (1.0)* (.74j (.41) (.62) (0) (.72)
Nofe. Numbers in parentheses are standard deviations. *p < .05 univariate test.
larger. Means and standard deviations for frequency and importance ratings of psychological benefits are presented in Table 3. Regarding the global rating of the importance of appearance benefits, high MAC scorers (M = 7.6, SD = 2.7) rated it higher than did low MAC scorers (M = 6.9, SD = 2.4), F( 1, 192) = 4.2, p = .04. For the specific appearance benefits, a MANOVA on the frequency of category endorsement was significant, Wilks’ lambda = .88, F(14, 188) = 1.9, p = .03. Univariate tests were significant for “clothing will fit better” (p = .Ol), “legs will be thinner” 0, = .05), and “will be more attractive to opposite sex” @ = .Ol), with high MAC scorers ratings being higher. On the mean ratings of appearance benefits, the MANOVA was also significant, Wilks’ lambda = .87, F(14, 188) = 2.1, p = .02. Univariate tests were significant for “clothing will fit better” @ = .004), “legs will be thinner” (p = .04), “thinner other” (p = .OS), and “more attractive to opposite sex” (JI = .03), with high MAC scorers ratings being larger. Means and standard deviations for frequency and importance ratings for appearance benefits are presented in Table 4. For the global rating of health benefits, a significant difference between high MAC scorers (M = 7.2, SD = 3.5) and low MAC scorers (M = 7.1, SD = 3.2) was not found, F(l, 192) = 1.1, p = .3. A MANOVA on the frequency of specific health benefits was not significant, Wilks’ lambda = .97, F(l0, 192) = .5, p = .9. Similarly, a MANOVA on mean ratings was not significant, Wilks’ lambda = .95, F(10, 192) = .9, p = .5. For the calorie restriction and burning strategies, individual t tests were conducted on the intensity scores. A MANOVA was not conducted due to the low number of subjects relative to the number of variables (Tabachnick & Fidell, 1983). On variables that had zeros in one cell, thereby precluding use of a t test, a Chi square was conducted on a yes/no frequency of strategy usage. For the calorie restriction strategies, 9 of the 27 strategies (13 including trends) were significantly different (see Table 5). Specifically, high MAC scorers had significantly higher intensity scores on “generally eat less” (p = .05), “fasting” @ = .02), “specific daily calorie limit” 0, = .04), “formal weight loss program” (p = .05), “high protein diet” @ = .03), “avoiding places where food is available” @ = .004), “eating at a consistent place or time” @ = .03), “self-reward for making daily calorie limit” @ = .Ol), and “eat only in kitchen or dining room” @ = .04). Trends were observed for “skipping meals” @ =
Criterion-related
validity of the MAC
159
Table 4. Specific appearance benefitMean importance endorsement frequencies
Benefit category Cloths fit Nicer clothes Thinner face Chest AllllS
waist Buttocks kegs Thighs Calves Other
Low MAC Ratmg Frequency 2.9 1.4 1.6 .13 .28 3.0 1.1 .34 1.2 .20 .35
(3.4) (2.6)* (2.8) (1.0) (1.3) (3.5) (2.7) (1.5)* (2.6) (1.2) (1.6)*
.49 .24 .29 .02 .06 .50 .14 .06 .18 .03
(.6Q) (.45)* (.53) (.13) (.24) (60) (.35) (.24)* (.38) (.16)
ratings and
High MAC Frequency
Ratmg 3.8 2.8 1.8 .41 .64 3.5 1.1 1.2 1.9 .15
(3.9) (3.6)* (3.1) (1.7) (2.0) (3.8) (2.7) (2.7)* (3.5) (1.0)
.65 .50 .30 .07 .ll .57 .15
(.72) (.75)* (.49) (.25) (.31) (.63) (.36) .19 (.42)* .25 (.44) .02 (.15)
.12
*p < .05 univariate test.
.lO), “weight control pills” @ = .OS), “serve meal on one plate” (p = .07), and “serve smaller portions” (p = .lO). For the calorie burning strategies, 5 of 23 strategies (7 counting trends) were significantly different, with high MAC scorers having higher intensity scores than low MAC scorers (see Table 6). Specifically, differences were found on “movie star exercise program” @ = .OS), “dance class or dancing” @ = .04), “gymnastics” (p = .Ol), “sit-ups, chin-ups, push-ups” @ = .Ol), and “ate foods to increase metabolic rate” @ = .Ol). Trends were observed for “jazzercise” @ = .08) and “jump rope” (p = .lO). DISCUSSION The MAC was developed to empirically assess cognitions thought to be related to anorexia and bulimia nervosa. Previous studies have supported the MAC’s criterion related validity, concurrent validity, factor structure, and internal consistency. Results of the current investigation further support the criterion-related validity of the MAC, and show that it is sensitive to subclinical differences in eating-related behavior and attitudes. In general, persons scoring high on the MAC showed more emphasis on weight regulation, placed greater emphasis on the psychological and appearance benefits of achieving or maintaining an ideal weight, used more calorie restriction strategies, and to a lesser extent, used more calorie burning strategies. Regarding emphasis on weight regulation, high MAC scorers had more frequently been involved in active attempts to maintain or lose weight in the previous six months, and rated it as more important to achieve or maintain their ideal weight. They also had a larger discrepancy between a DHEW ideal weight and their self-ideal weight, showing an endorsement of biologically unrealistic low weights. For the benefits of achieving or maintaining ideal weight, high MAC scorers showed strong endorsement of the importance of the psychological benefits of ideal weight, as evidenced by a global rating of importance. On an open-ended listing and importance rating of specific psychological benefits, high MAC scorers indicated greater endorsement of the
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Table 5. Calorie burning strategy intensify scores Strategy Running, jogging Swimming Bicycling Movie star exercise program** Richard Simmons’ exercise program Weight Lifting Jazzercise* Dance class or dancing** Jump rope* Tennis Walking Racquetball/squash Basketball Gymnastics** Sauna or steam bath Plastic pants or belts Increase routine exercise Self-reward for exercise Cellulite removal” Vibrating belts/rollers” Sit-ups, chin-ups, push-ups** Foods to increase metabolic rate** Othef
Low MAC 98.3 13.9 17.0 0.9 1.5 66.7 0.5 3.0 2.0 3.6 31.9 13.5 15.7 0.2 3.5 2.1 41.8 1.1 0 0 23.2 0.2 0
(681.1) (46.6) (40.0) (3.6) (8.7) (455.9) (2.8) (9.5) (11.6) (11.7) (70.1) (76.2) (86.9) (1.7) (15.8) (15.6) (206.9) (9.6) (0) (0) (43.4) (1.4)
Note. Numbers in parentheses are standard deviations. “Chi-square conducted due to no variance in 1 group, strategy. *p < .lO. **p < .05.
High MAC 39.3 22.1 44.0 5.0 2.1 13.5 2.2 8.9 6.2 3.5 33.8 5.4 39.5 2.5 6.8 1.3 63.0 1.9 1.2 1.1 43.6 7.7 15
(93.9) (78.9) (195.3) (22.1) (10.5) (35.5) (10.1) (27.5) (23.7) (11.0) (70.1) (28.9) (196.3) (9.5) (20.0) (9.6) (197.1) (12.0) (8.9) (10.0) (71.6) (36.2) (140.9)
data recorded
f statistic 0.8 0.9 1.4 1.9 0.4 1.1 1.8 2.1 1.7 0.1 0.2 1.0 1.2 2.5 1.3 0.4 0.7 0.5 2.2 0.8 2.5 2.2 1.9
as yes/no on use of
belief that ideal weight would result in people liking them more and in improvements in their social life. While several other potential particular benefits of ideal weight were listed, it is interesting that these beliefs were two of the most frequently occurring. These two categories would be expected to be highly related to the MAC given the presence of the “weight and eating behavior as the basis of approval” factor. For the appearance benefits of ideal weight, high MAC scorers showed a higher global endorsement of this belief. For the specific appearance benefits, high MAC scorers indicated greater endorsement of being able to wear nicer clothes that fit better, of having thinner legs, and of being more attractive to the opposite sex. Again, the emphasis on approval from others is noted. It is interesting that simply “looking better” did not discriminate high and low MAC scorers, but being attractive did. This would suggest physical attractiveness per se is not the issue, but rather physical attractiveness as the basis of approval from others. This distinction is consistent with the construction of the items for the “approval” subscale of the MAC. In addition, the distinction is consistent with theorizing about the specific nature of the pathological emphasis on weight and appearance. That is, it is one thing to want to look nice, it is quite another to see appearance as a major mechanism for gaining approval and self-esteem. High and low MAC scorers did not differ on the importance of health benefits, either for the global rating or for specific benefits. Theoretically, this could be predicted since the pathological attitudes that the MAC is designed to assess has little to do with health issues relevant to weight. Rather, the focus is on psychological and social variables. The data on weight benefits are particularly useful because of the manner in which they
Criterion-related
validity of the MAC
Table 6. Calorie restriction Strategy Generally eat less** Fasting** Scarsdale diet” Weight Watchers diet Skipping meals* Stillman’s Water diet Diabetic Food Exchange” Specific daily calorie limit** Eliminate/reduce sweets Self-induced vomiting Laxative? Diuretics Weight control pills* Starch blockers” Grapefruit diet Formal weight loss program**a High fiber diet Smoke or drink caffeine High protein diet**’ Avoid food places** Consistent eating place/time** Limit “forbidden food” access Self-reward /self-monitor food intake** Serve 1 plate of food* Serve smaller portions* Serve food on smaller plates Eat only in kitchen**
161
strategy intensity scores Low MAC
42.8 0.2 0 0 27.9 0 0 3.3 37.9 0.0
(87.0) (1.4) (0) (0) (127.0) (0) (0) (17.3) (145.3) (0.1)
0 (0) 0.1 2.8 0.2 0.2 0.7 42.6 0 2.6 4.7 23.8 0.4 0.2 15.2 2.6 5.5
(0.9) (14.7) (2.6) (1.2)
io, (6.8)
(328.2) (0) (11.5) (26.2) (123.0) (2.9) (2.0) (65.5) (17.9) (25.4)
Note. Numbers in parentheses are standard deviations. “Chi-square conducted due to no variance in 1 group, strategy. *p < .lO. **p < .05.
High MAC 90.5 3.8 0.5 0
t statistic
(237.3) (15.7) (3.3) (0)
2.0 2.4 1.5 -
88.5 (362.7) 0 (0)
1.7 -
5.7 (47.0) 13.5 (48.6) 34.7 (57.8) 3.0 (23.5) 1.6 (13.2) 1.5 (13.2) 9.1 (34.5) 0 (0) 1.9 (17.5) 3.4 (15.9) 2.9 (26.1) 17.7 (45.4) 5.4 (41.9) 27.1 (87.8) 18.1 (55.7) 38.0 (89.3) 4.7 (17.1) 11 .O (62.5) 31.7 (78.3) 4.6 (15.2) 14.9 (40.1)
1.5 2.1 0.2 0.2 1.5 1.2 1.8 0 1.0 3.8 0.9 0.7 4.8 2.9 2.2 0.9 2.6 1.8 1.6 .9 7.1
data recorded
as yes/no on use of
are collected. Because subjects did not respond to objective questionnaires in addition to the MAC, the likelihood of method error variance is reduced. Also, by allowing subjects to list freely the benefits they found important, we have a much better idea of what the population of relevant weight benefits are in the normal population. This allows greater confidence in the validity of any associations observed with MAC scores. Persons scoring higher on the MAC showed a greater tendency to be involved in a variety of calorie restricting activities. These included generally eating less, fasting, having a specific daily calorie limit, using weight control pills, participating in a weight loss program, going on a high protein diet, and self-rewarding for staying within a daily calorie limit. Also included were a variety of stimulus control strategies such as avoiding places where food is available, having a consistent eating place or time, serving only one plate of food, serving smaller portions, and eating only in the kitchen. While not statistically significant, data for a few particularly pathological low frequency behaviors were notable. Laxative abuse was endorsed by three high MAC scorers, but none of the low MAC scorers. Self-induced vomiting was reported by six high MAC scorers, but only one low MAC scorer. Persons scoring higher on the MAC showed some tendency to be engaged in more exercise or other calorie burning activities. Specifically, high MAC scorers were more likely to use a movie star’s exercise program (such as the Jane Fonda workout), participate in jazzercise, dance class or dancing, gymnastics, jumping rope, calisthenics such as sit-ups, chin-ups, and
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push-ups, and to eat foods presumed to increase metabolic rate. While several physical activities did not discriminate high and low MAC scorers, an interesting pattern emerged. Activities associated with recreation or health (i.e., swimming, running, tennis) did not differ, while those associated with improving appearance (Jane Fonda workout, dance class) did show differences. Also, consistent with sex-role expectations regarding the importance of appearance, the discriminating activities were those that women tend to engage in for appearance reasons. While the data for the calorie restriction and calorie burning strategies support the validity of the MAC, it is important to note that these data are retrospective self-reports and subject to the limitations of accurate recall. This is less of a concern for a simple indication of whether a strategy was used or not, more so for the “intensity” of use. While recognizing this limitation, this self-report assessment was felt to be a practical compromise between obtaining the potentially more sensitive measure of intensity of strategy use versus the sizeable problem of following 200 people over 6 months and accurately logging their calorie burning and restriction activities. Also, the large number of statistical tests for the calorie restriction and calorie burning strategies raises the possibility of Type I error. This is less of a concern for the calorie restriction strategies because several significant effects were found. However, fewer significant effects were found for calorie burning strategies, so these results should be viewed more conservatively. Overall, the findings of the current study support the criterion-related validity and sensitivity of the MAC, adding to the growing research supporting the psychometric characteristics of the questionnaire. As the MAC’s utility is hopefully supported, it may serve a valuable role as a valid and reliable measure of presumed eating disordered cognitions. This will allow research on the role of cognitions in anorexia and bulimia to proceed from a firmer empirical base. As well, the MAC may eventually become a useful clinical tool.
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of
Criterion-related
validity of the MAC
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Schulman, R.G., Kinder, B.N., Powers, P.S., Prange, M., & Gleghorn, A. (1986). The development of a scale to measure cognitive distortions in bulimia. Jourd of PersonalityAssessment, 50, 630439. Tabachnick, B.G., & Fidell, L. (1983). Using multivariate statistics. New York: Harper $ Row. Wardle, J., & Beales, S. (1987). Restraint and food intake: An experimental study of eating patterns in the laboratory and in normal life. Behavior Research Therapy, 25, 179-185.
