The effectiveness of a behavioral weight reduction program for moderately retarded adolescents

BEHAVIORTHERAPY11, 410-416 (1980)

The Effectiveness of a Behavioral Weight Reduction Program for Moderately Retarded Adolescents ANTHONY F. ROTATORI Northern Illinois University

ROBERT F o x Western Illinois University

Thirty moderately mentally retarded adolescent subjects were assigned to either a Behavior Therapy (n = 12), a Social-Nutrition (n = 12), or a Wait-List Control group (n = 6). The behavior therapy subjects lost significantly more weight than the nutrition and control subjects. The behavior therapy subjects continued to lose weight dunng maintenance and follow-up conditions. Recently attention has been directed towards demonstrating the effectiveness of behavioral approaches to weight control with mildly retarded individuals (Foxx, 1972; Rotatori, Fox, & Switzky, in press; Staugaitis, 1978). The present study assessed the effectiveness of a multicomponent behavioral weight reduction program for overweight, moderately retarded adolescents. Essentially, the treatment program was a simplification of traditional behavioral weight programs (Hall, 1972; Stuart, 1969). This simplification involved the substitution of modeling and demonstration for verbal explanation and the minimization of academic skills necessary to complete self-monitoring forms. Additionally, training sessions involved " l i v e " practice with food as well as the attainment of mastery levels (Rotatori, 1978) for each technique taught prior to the introduction of a new technique. METHOD Subjects

Thirty moderately retarded adolescents who resided with their parents were r e c o m m e n d e d by their teachers to participate in a weight reduction program. All subjects attended vocational-oriented programs in a public Requests for reprints should be sent to Anthony F. Rotatorl, Department of Learning and Development, Northern Illinois University, Graham Hall 229, DeKalb, IL 60115 410 0005.7~)4¢~¢0410-..041651001'0 Copyright19~0by Assoclatton for Advancement of Behavior Therapy Allrightsof reproducUon in any form reserved

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high school. The following selection criteria were met by all subjects: (a) moderate mental retardation, (b) were not taking medication for weight loss, (c) were at least 10% overweight (Robinson, 1967), and (d) were not presently involved in any other weight program. Twelve subjects were randomly assigned to each a Behavior Therapy and a Social-Nutrition group. The remaining six subjects comprised the Wait-List Control group. Table 1 shows the ages, I.Q. scores, and initial percent overweight for the three groups.

PROCEDURE Behavior Therapy Parental involvement. Prior to initiating the program, parents of the subjects attended an inservice meeting. Parents were trained in the behavioral weight reduction techniques and familiarized with the recording forms to be completed by their child. The parents' role during the programs' implementation included (1) assisting their child with self-monitoring forms, (2) providing directions and feedback in carrying out the behavioral techniques, and (3) administering home reinforcement for weight loss. Subject~teacher involvement. The subjects met with their vocational teacher three times a week during the 14-week training phase. The meetings were designed to instruct the subjects in behavioral techniques for weight reduction and in procedures for completing homework assignments (i.e., food diary, daily weight records). The behavioral approaches which were trained included the following: the manipulation of emotional responses (Hall, 1972), food cue elimination techniques (Stuart, 1969), changing the acts of eating (Stuart & Davis, 1972), using energy to burn up unneeded calories, and developing alternative activities to eating (Ferguson, 1975). Two new procedures were introduced each week. The manipulation of emotional responses involved instructing subjects to verbalize aversive consequences when tempted to overeat (e.g., " m y boyfriend will call me fatty") and to verbalize pleasant consequences when the subject was successful in not overeating (i.e., " I ' m going to look great"). Food cue elimination techniques involved specifying one place to eat meals and snacks, leaving some food behind on the plate, and taking only one helping. Changing the act of eating included eating slower, chewing food completely, and putting utensils down on the table between bites. The development of alternative activities to eating involved encouraging the subjects to engage in pleasant activities which compete with eating, such as going for walks, listening to records, or working on a craft project. Lastly, the subjects were instructed to burn up unneeded calories by engaging in a 10-minute exercise period twice a day. A number of instructional modalities were employed to facilitate the retarded subjects' understanding of the behavioral procedures during the

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TABLE 1 AGES, I.Q.'s, AND PERCENTOVERWEIGHTFOR BEHAVIORTHERAPY,SOCIAL-NUTRITION, AND WAIT-LISTCONTROLGROUPSUBJECTS Ages in Years Group Behavior Therapy ~ Social-Nutritiona Walt-List Controlh

N

f(

12 12 6

18 20 17 90 17 65

S.D

1 79 1 62 1 80

IQ

Percent Overweight

.f(

S.D.

.X

44 50 45 10 44 75

3 20 2 99 2.85

20 50 19 80 20 10

S.D

9,90 10.80 10.10

a (6 males, 6 females ) (3 males, 3 females )

intervention phase. First, the behavioral p r o c e d u r e s were verbally described along with a simple rationale. The teacher then modeled the procedure for the subjects. This demonstration was followed b y each subject practicing the p r o c e d u r e in a simulated situation. F e e d b a c k was provided to the subjects on their practice trials. Additional f e e d b a c k was provided to the subjects by the teacher who o b s e r v e d the subjects during lunch periods. Parents were required to write regular progress notes of the subject's utilization of the techniques to increase the usage of the techniques in the home. The notes were followed up with bimonthly phone calls to the parents by the teacher to discuss in detail the progress of the subjects in attaining m a s t e r y of the techniques as well as implementation concerns. These progress notes and phone calls served as reliability checks to assess p r o g r a m implementation in the home. R e i n f o r c e m e n t c o m p o n e n t . During the intervention phase, all subjects received school and h o m e reinforcement at the end of the school week for weight lost. Subjects had to lose one point or m o r e since the previous session's weight to receive reinforcement for weight lost. The h o m e reinforcement was an activity desired by the subject (e.g., bowling with dad) whereas the school reinforcement was a group activity (e.g., classr o o m dance on Friday afternoon) chosen by the majority of subjects. Additionally, the subjects rated their p e r f o r m a n c e daily on the techniques that had been trained on a b e h a v i o r checklist. Based on their ratings, the subjects received a grade which was dependent upon total points earned for employing the techniques. The particular grades earned were then exchanged for an envelope which contained self-reinforcement guidelines. The self-reinforcement guidelines were divided into two areas, activity reward and self-administered positive statement. M a i n t e n a n c e c o n d i t i o n . The maintenance training phase began immediately following the 14-week treatment period and lasted for 5 weeks. During this p h a s e all subjects attended a total of five sessions. The maintenance meetings included a videotape presentation which reviewed the behavioral techniques presented during the intervention phase and a re-

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view of self-monitoring forms. Home and school reinforcement conditions were continued during this phase. Social-Nutrition Subjects in this group met approximately four times a week. The meetings were led by the school nurse. Topics for discussion included (1) good nutritious foods to eat, (2) low calorie snack substitutes, (3) the advantages of exercising, (4) reasons not to eat when emotionally upset, (5) talking about negative feelings associated with being overweight, (6) being positive about losing weight, and (7) setting weight goals. Any subject who lost weight was verbally praised by the nurse at the time of the weigh-in. Wait-List Control Control subjects were informed that the weight reduction program was filled and another program would be started later. Subjects were encouraged to lose weight on their own and informed that the diet leader (school nurse) would weigh them periodically during the next few months to assess their progress. Follow-up Sixteen weeks following the conclusion of the maintenance condition the body weights of all subjects were obtained at a weigh-in at the school. No formal treatment was in effect during this period. Also at this time a new behavioral weight program was started for subjects in the Wait-List Control group.

RESULTS The Kruskal-Wallis H test (Welkowitz, Ewen, & Cohen, 1976), a nonparametric one-way analysis of variance measure, was chosen for the data analysis as the assumptions underlying the parametric ANOVA model (particularly the homogeneity of variance assumption) were not adequately met in the present study. The Kruskal-Wallis H test allowed for comparisons between the three groups on both the matching variables and the dependent variable. A Kruskal-Wallis H test comparing ages, I.Q. scores, and initial percent overweight indicated no significant differences between the three groups on these variables (H = 5.66 for age, H = 4.79 for I.Q., and H = 4.01 for percent overweight p >.05). Active Treatment Fig. 1 presents the mean percentage body weight changes for the three groups during the experimental conditions. ANOVA H test comparing percentage weight change from pre to post weigh-ins between the three groups yielded a significant group difference (H = 20.35, p < .01). The protected Rank Sum Post Hoc Test (Welkowitz et al., 1976) revealed the

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SOCIAL-NUTRITION N-lZ

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PRE

TREATMENT MEASURE

i i

POST

POST

TREATMENT MAINTENANCE (WEEK 14) (WED(19)

FOLLOW - UP (WEEK35)

FIG 1 Meanpercentage weight loss or gain for the experimental and control subjects.

following differences at .05 level of significance: Behavior Therapy > Social-Nutrition, Behavior Therapy > Wait-List Control, and Social-Nutrition > Wait-List Control. Subjects in the Behavior Therapy and SocialNutrition groups had a mean weight loss of 10.27 and .08 pounds with a weekly average weight loss of .73 and .006 pounds per subject, respectively. In contrast the Wait-List Control group had a mean weight gain of 4.42 pounds with a weekly average weight gain of .31 pounds per subject.

Maintenance The percentage weight change of the three groups during a postmaintenance weigh-in revealed a significant difference (H = 12.19, p < .01). The following significant differences were revealed by Protected Rank Sum tests: (1) Behavior Therapy > Social-Nutrition, (2) Behavior Therapy > Wait-List Control, and (3) Social-Nutrition > Wait-List Control. Subjects in the Behavior Therapy and Social-Nutrition groups had a mean weight loss of 2.29 and .6 pounds with a weekly average weight loss of .46 and .03 pounds per subject, respectively. Control subjects had a mean weight gain of 1.25 pounds with a weekly average weight gain of .25 pounds.

Follow-up During the 16-week follow-up condition, a Kruskal-Wallis H test comparing percentages weight change of the three groups revealed a significant difference ( H = 13.36, p < .01). Protected Rank Sum tests indicat-

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ed the following significant differences: (1) Behavior T h e r a p y > Social Nutrition and (2) Behavior T h e r a p y > Wait-List Control. The B e h a v i o r T h e r a p y subjects had a m e a n weight loss 1.94 pounds with a w e e k l y average weight loss of .12 pounds per subject. In contrast the SocialNutrition and Wait-List Control had a mean weight gain of 1.83 and 3.00 pounds with a w e e k l y average weight gain of .11 and .19 pounds per subject, respectively.

DISCUSSION The Behavior T h e r a p y group lost significantly m o r e weight under all conditions than either the Social-Nutrition or Wait-List groups. The weight loss in the Behavior T h e r a p y group was clinically impressive as a m e a n b o d y weight change of 9.5 p e r c e n t was obtained. Hall (1972) indicated that studies which have p r o d u c e d significant weight loss findings have reported weekly weight loss rates which have ranged f r o m .50 to 1.00 pounds. The findings of the p r e s e n t study c o m p a r e f a v o r a b l y as the subjects in the Behavior T h e r a p y group attained weekly weight losses of .73 pounds per w e e k during the t r e a t m e n t training period. More significantly for the present study, Behavior T h e r a p y subjects continued to lose weight at the time of follow-up. This finding is meaningful b e c a u s e dieters often regain lost weight after active t r e a t m e n t terminates (Stuart & Guire, 1978). A limitation of the p r e s e n t study was the reliability with which the treatment p r o c e d u r e s were carried out in both the Behavior T h e r a p y and Social-Nutrition groups. Although attempts at obtaining this data were subjectively made in the Behavior T h e r a p y group (e.g., reviewing the forms completed by the subjects; using parental progress notes and phone calls), future research should include specific reliability checks to verify the subjective data. The present t r e a t m e n t involved a " b e h a v i o r strategy p a c k a g e . " In such a program, one c a n n o t identify which technique(s) are responsible for b e h a v i o r change. H o w e v e r , as Azrin (1977) has stressed, p a c k a g e p r o g r a m s can be used " u n a p o l o g e t i c a l l y , " as little is gained b y limiting the therapist to partial benefits for the sake of achieving experimental purity.

REFERENCES Azrm, N. H. A strategy for applied research: Learning based but outcome orientated. American Psychologist, 1977, 32, 140-149. Ferguson, J. M. Learning to eat: Behavior modification f o r weight control. Palo Alto: Bull Publishing Co , 1975 Foxx, R.M. Socialreinforcement of weight reduction: A case report on an obese retarded adolescent. Mental Retardation, 1972, 10, 21-23. Hall, S M. Self-control and therapist control in the behavioral treatment of overweight women. Behavtour Research and Therapy, 1972,10, 59-68. Robinson, C.H. Normal and therapeutic nutrition. New York: MacMillan, 1967 Rotatorl, A. F. The effect of different reinforcement schedules on the maintenance of weight loss with retarded overweight adults previously exposed to a behavioral weight reduction treatment package (Doctoral dissertation, University of Wisconsin, 1977).

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Dissertation and Abstract International, 1978, 38, 4738-N (University Microfilms No. 77-19, 7882). f . Rotatorl, A F., Fox, R , & Swltzky, H. Multlcomponent behavioral program or achieving weight loss in the adult retarded Mental Retardation, in press. Staugaitls, S. D New directions for effective weight control with mentally retarded people. Mental Retardation, 1978, la, 157-161. Stuart, R . B . Behavioral control of overeating. Behavlour Research and Therapy, 1969, 5, 357-365 Stuart, R B., & Davis, B. Shm chance tn a fat world Behavioral control of obesity Champaign, IL" Research Press, 1972 Stuart, R. B., & Gulre, R. Some correlates of the maintenance of weight lost through behavior modification. International Journal o f Obesity, 1978, 2, 225-235 Welkowltz, I., Ewen, R. B . & Cohen, J. Introductory statistics for the behavioral sciences. New York: Academic Press, 1976 RECEIVED" June 22, 1979, REVISED November 6, 1979 FINAL ACCEPTANCE" November 16, 1979