Self-directed weight control through eating and exercise

A weight control program using a written contract and other self-control behavior modification techniques for changing eating habits was compared with a similar program concentrating on both eating and exercise behavior and with an attention-placebo control condition. Participants in all three programs lost weight during the 12 week program, with no significant differences between groups. A seven-month follow-up revealed that Ss in the two behavior modification groups lost more than those in the control group and that those in the eating plus exercise group lost more than those in the group dealing only with eating behavior.     

Diminished weight loss and behavioral compliance during repeated diets in obese patients with type II diabetes.

Compared weight losses during first and second bouts of a very low calorie diet (VLCD) and examined whether decreased compliance might in part explain the decrease in weight loss during the second bout. Forty-five Type II diabetic patients participated in a year-long behavioral weight-reduction program that incorporated a VLCD (400 to 500 kcal/day) during Weeks 1 to 12 and 28 to 40. Weight losses decreased dramatically from the first to the second VLCD (15.54 vs. 1.42 kg, p less than .0001). There was also markedly diminished adherence as assessed by weeks ketonuric, attendance, and completeness of self-monitoring records. The percentage of weeks subjects were in ketosis dropped from 61% during VLCD 1 to 13% during VLCD 2 (p less than .0001). Similarly, subjects attended significantly fewer treatment meetings during VLCD 2 and self-monitored less during VLCD 2 than during VLCD 1. Weeks ketonuric and initial weight accounted for 63% of the variance in weight loss during VLCD 1 (p less than .0001); weeks ketonuric and attendance predicted weight loss during VLCD 2 (p less than .0001), accounting for 54% of the variance. These results suggest the importance of behavioral factors in explaining poorer performance on a repeated diet.     

A comparison of a self-control and a contract procedure for weight control

A self-control procedure involving the use of behavior modification techniques was compared with a contract system and an attention-placebo control group. One study revealed significant losses for both treatments after 12 weeks with the contract group losing more; however, a ten month follow-up revealed that the weight loss was not permanent. A second study found no differences between a self-control group and a control group after 16 weeks. Reasons for the poor long-term results of these and other weight-control programs were discussed.     

Perceived calorie intake and state body-image satisfaction in women attempting weight loss: A preliminary investigation

State body-image satisfaction levels (BIS) can be predicted by appearance concerns, eating attitudes and body mass index (BMI). Determinants of state BIS and its variability were examined in women attempting weight loss. Little is known about contextual cues that influence state BIS; therefore the effect of eating on BIS was examined. Forty-six females attending a commercial weight loss group completed measures of shape and weight concerns, appearance beliefs and dietary restraint, followed by completion of a diary that assessed state BIS, mood and perceived calorie intake immediately following evening meals. Regression analysis indicated that after controlling for mood, state BIS was associated with higher BMI and dietary restraint. Greater variability in state BIS was associated with greater variability in perceived calorie intake. This relationship was fully mediated by greater variability in mood. The findings imply that state BIS warrants investigation as a process that may influence weight loss management.     

INCREASING THE IMMUNIZATION OF PRESCHOOL CHILDREN; AN EVALUATION OF APPLIED COMMUNITY INTERVENTIONS

We evaluated the relative impact of four procedures designed to encourage parents to obtain immunizations for their children. In a public health setting, the families of 1,133 immunization-deficient preschool children were randomly assigned to six conditions: (a) a general prompt; (b) a more client-specific prompt; (c) a specific prompt and increased public health clinic access; (d) a specific prompt and monetary incentives; (e) contact control; and (f) no contact control. All interventions, except the general prompt, produced some evidence of improvement when compared with the control groups. The monetary incentive group revealed the largest effect, followed by the increased access group, specific prompt group, and general prompt group, respectively. The data suggest that relatively powerful and immediate effects on preschoolers' clinic attendance for immunization may be produced by monetary incentives in conjunction with client-specific prompts. However, client-specific prompts alone appear to be the most cost-effective of the interventions.     

Behavior therapy for obesity: Booster sessions and long-term maintenance of weight loss

Following 8 weekly sessions of group behavioral self-control treatment, 75 obese women were assigned to one of five different maintenance conditions: (a) structured behavioral booster sessions held every two weeks; (b) structured behavioral booster sessions held every month; (c) unstructured nonspecific booster sessions held every two weeks; (d) unstructured nonspecific booster sessions held every month; and (e) a control group that received no booster sessions. Follow-ups were conducted at 3, 6, 9 and 12 month intervals. The study was completed in two replications. Results failed to show a significant effect of either booster session content or frequency. All groups continued to lose weight during the first three months of follow-up. Thereafter subjects in Replication 1 showed significant increases in weight over the next 9 months, whereas subjects in Replication 2 maintained their treatment-produced weight loss. The data do not support the view that booster sessions facilitate maintenance.     

Individual differences in self-reinforcement style and performance in self-and therapist-controlled weight reduction programs

Thirty-seven overweight subjects were recruited from the staff of a V. A. Hospital for a weight reduction program. A self-reinforcement (SR) test was administered prior to treatment and subjects were classified as high or low self-reinforcers. Subjects were then exposed to one of two behavioral weight-reduction programs or a minimal treatment control condition. One treatment program emphasized self-control (SC) and the other incorporated a therapist controlled financial contingency for weight loss (EC). A significant interaction was found between SR group and treatment condition. High SR subjects lost weight at the rate of 1.49 pounds per week in the SC condition and only 0.37 pounds per week in EC. Low SR subjects lost at the rate of 1.06 and 1.01 pounds per week respectively in SC and EC. Implications for treatment and future research were discussed. The financial contingency had either neutral or negative effects. Caution was advised for any future use of that procedure.     

Predictors of attrition and weight loss success: Results from a randomized controlled trial

Attrition is a common problem in weight loss trials. The present analysis examined several baseline and early-treatment process variables, as predictors of attrition and outcome in a clinical trial that combined pharmacotherapy and behavior therapy for weight loss. Participants were 224 obese adults who were treated with sibutramine alone, lifestyle modification alone, combined therapy, or sibutramine plus brief lifestyle modification. Predictors included baseline characteristics (e.g., demographic, weight-related, psychological, and consumption-related variables), plus attendance, adherence, and weight loss in the early weeks of treatment. Outcomes were attrition and weight loss success (i.e., ≥5% reduction in body weight) at 1 year. Multivariable models, adjusting for other relevant variables, found that younger age and greater baseline depressive symptoms were related to increased odds of attrition (ps ≤ 0.003). Greater early weight loss marginally reduced the odds of attrition (p = 0.06). Predictors of weight loss success at 1 year were Caucasian ethnicity (p = 0.04), lower baseline depressive symptoms (p = 0.04), and weight loss during the first 3 weeks of treatment (p < 0.001). Thus, depressive symptoms at baseline were a significant predictor of both attrition and weight loss success. As a process variable, early weight loss appears to have more predictive value than early attendance at treatment sessions or early adherence.     

Cognitive dissonance and psychotherapy: The role of effort justification in inducing weight loss

The role of effort justification in psychotherapy was examined. It was hypothesized that the effort involved in therapy, plus the conscious decision to undergo that effort, leads to positive therapeutic changes through the reduction of cognitive dissonance. An experiment was conducted in which overweight subjects attempted to lose weight through one of two forms of “effort therapy”. These therapies were bogus in that they were based solely on the expenditure of effort on a series of cognitive tasks that were unrelated to any existing techniques or theory addressing weight loss. One of the therapies called for a high degree of effort while the degree of effort in the second therapy was low. A no-treatment control group was also included. It was predicted that greater weight loss would occur for high-effort than low-effort or control subjects, and that this weight loss would be maintained or increased over time. Results supported these predictions. Over an initial 3-week period, high-effort subjects lost slightly more weight than low-effort subjects or controls. A 6-month follow-up revealed that the effects of effort on weight loss had increased and were highly significant. Reliable differences remained even 1 year after the initial experimental sessions. Possible mechanisms mediating the dissonance effect were discussed, as were several alternative explanations.     

Clinical and experimental utility of refundable deposits

The purpose of this study was to investigate the effects of a refund system on court-referred clients' adherence to the attendance and data-collection requirements of a program contract. Male and female clients admitted to a group treatment program for driving under the influence of alcohol were or were not required to place a $50 refundable deposit at the beginning of treatment. The results showed that subjects in the refundable deposit groups had fewer unexcused absences and were more efficient in returning data-collection forms, suggesting that deposits have considerable utility in a clinical/research setting.     

Challenging body weight: evidence from a community-based intervention on weight,behaviour and motivation

The objective of this study was to examine the effectiveness of a 12 week weight loss intervention within a commercial fitness centre on body weight, moderate to vigorous physical activity (MVPA), dietary intake, and behavioural regulations for exercise and healthy eating. Using a quasi-experimental design, the intervention group received weekly coaching sessions and bi-weekly seminars designed to increase MVPA and improve dietary intake. Outcome variables were assessed at three time points over a six month period. Results showed a significant interaction for body weight (p = .04) and dietary changes (p < .05) following the weight loss challenge but were not maintained across the six month period. Changes in behavioural regulations favoured the intervention condition. Results imply that a 12 week weight loss challenge within a commercial fitness centre may be effective at prompting short-term weight loss and support the internalization of behavioural regulations specific to healthy eating and exercise.     

海洛因戒断者对金钱奖赏的反馈加工异常：来自ERP的证据

本研究采用金钱奖赏延迟任务考察了海洛因戒断者对金钱奖赏和损失的预期和反馈加工及其电生理机制。结果发现,预期阶段两组被试由不同线索诱发的P3波幅不存在显著差异。在金钱奖赏加工的反馈阶段,海洛因戒断组由金钱收益条件诱发的RewP波幅显著小于对照组由金钱收益条件诱发的RewP波幅,而在无收益无损失条件下两组被试诱发的RewP波幅不存在显著差异。此外,海洛因戒断组由金钱收益条件诱发的P3波幅与无收益无损失条件诱发的P3波幅不存在显著差异,而对照组由金钱收益条件诱发的P3波幅显著大于其由无收益无损失条件诱发的P3波幅。在金钱损失加工的反馈阶段,由金钱损失和无收益无损失条件诱发的RewP波幅在两组被试之间不存在显著差异,且两组被试由金钱损失条件诱发的P3波幅均显著大于其由无收益无损失条件诱发的P3波幅。以上结果说明海洛因戒断者对金钱奖赏的反馈加工存在异常,具体表现为其对金钱奖赏的敏感性降低或对金钱奖赏的趋近动机减弱。     

Interdependent Group Contingency Management for Cocaine-Dependent Methadone Maintenance Patients

Contingency management (CM) for drug abstinence has been applied to individuals independently even when delivered in groups. We developed a group CM intervention in which the behavior of a single, randomly selected, anonymous individual determined reinforcement delivery for the entire group. We also compared contingencies placed only on cocaine abstinence (CA) versus one of four behaviors (CA, treatment attendance, group CM attendance, and methadone compliance) selected randomly at each drawing. Two groups were formed with 22 cocaine-dependent community-based methadone patients and exposed to both CA and multiple behavior (MB) conditions in a reversal design counterbalanced across groups for exposure order. The group CM intervention proved feasible and safe. The MB condition improved group CM meeting attendance relative to the CA condition.     

Effects of preexisting and manipulated self-efficacy on weight loss in a self-control program

The present study was designed to investigate the effects of self-efficacy on weight loss utilizing self-control techniques. Subjects high and low in preexisting self-efficacy were randomly assigned to high or low manipulated self-efficacy groups in a 2 × 2 (preexisting self-efficacy × manipulated self-efficacy) factorial design. Preexisting self-efficacy was assessed using procedures employed byBandura and Adams (1977, Cognitive Therapy and Research, 1, 287–308). Selfefficacy was manipulated by having subjects attribute successful task performance to a previously unrecognized capacity for self-control. Subjects met in groups once a week for a total of 8 weeks and received a comprehensive weight control program within the context of self-control. Results indicated significant manipulated and preexisting × trials interactions with both the high manipulated and preexisting self-efficacy groups losing more weight over the 8 weeks than the low preexisting and manipulated groups. In addition, locus of control was predictive of weight loss, with internals tending to lose more weight than externals. Results are discussed in terms of Bandura's (1977, Psychological Review, 84, 191–215) theory of self-efficacy.     

TREATING OVERWEIGHT CHILDREN THROUGH PARENTAL TRAINING AND CONTINGENCY CONTRACTING1

Fifteen overweight girls aged 5 to 11 yr were randomly assigned to one of two weight-reduction treatments: response-cost plus reinforcement, response-cost only, or a no-treatment control group. In the response-cost plus reinforcement group, parents contracted to facilitate their child's weight loss by carrying out reinforcement and stimulus control techniques, completing weekly charts and graphs, and encouraging their child to exercise. The response-cost only group parents did not contract to reinforce their child's performance. The response-cost program applied to both experimental groups was conducted in weekly meetings in which parents lost previously deposited sums of money. Twenty-five per cent was deducted for missing the weekly meeting, 25% for failing to fill out charts and graphs, and 50% if their child failed to meet her specified weekly weight-loss goal. At the end of the 12-week treatment period, both experimental groups had lost significantly more weight than the control group. After an eight-week, no-contact follow-up, some of the lost weight was regained. The response-cost plus reinforcement group was still significantly below the controls. The response-cost group just missed significance. A 31-week, no-contact follow-up failed to show a treatment effect, but did show a trend towards slower weight gain by the response-cost plus reinforcement group.     

Preventing weight gain in adults: a pound of prevention

This study evaluated the feasibility and effectiveness of a program for weight gain prevention in normal-weight adults. Two hundred nineteen participants were randomized to either weight gain prevention treatment or no treatment for a period of 12 months. Those in the treatment group received monthly newsletters relating to weight management, participated in a financial incentive system, and were offered an optional four-session education course in the sixth month of the program. Results demonstrated high interest in weight gain prevention among individuals who were not objectively overweight. Participation, as measured by return of postcards sent with each newsletter, was approximately 75%. Results after 1 year showed a net weight loss in the group receiving the program of 1.8 lb compared to those in the control group. Eighty-two percent of program participants maintained or lost weight, compared to 56% of the control group. It is concluded that programs for weight gain prevention are feasible in adults and may be more effective than weight loss treatment programs in addressing the problem of community-wide obesity.     

Exploration of likely engagement with Monetary Contingency Contracts for weight loss: a questionnaire study

Monetary Contingency Contracts (MCCs) are schemes that ask individuals to pledge money that is returned contingent on behaviour change. In relation to weight loss, this study explored likely levels of engagement with MCCs, how much individuals would be willing to pay into an MCC, and how these amounts vary under different contract conditions. Fifty-six individuals with BMI above 25 who were motivated to lose weight were recruited. The majority of participants (87.5%) indicated that they would be willing to engage with weight loss MCCs, but showed more reluctance to subscribe to pair-based MCCs which offered; (a) refunds contingent on the weight loss of a weight loss partner, and (b) ‘all or nothing refunds’ in which no reward is given for any weight loss below the target weight loss goal. This study provides preliminary evidence that individuals motivated to lose weight may be willing to engage with weight loss MCCs. Further research is needed to explore reasons for reluctance to subscribe to MCCs with certain conditions, to inform the design of future experimental studies testing the efficacy of MCCs as part of an intervention for weight loss.     

Value self-confrontation as a method to aid in weight loss

The impact on weight loss of an adaptation of the Rokeach (1973) value self-confrontation method was investigated in a field experiment. This method confronts people who have ranked their own values with information about the value priorities that discriminate between a positive and a negative reference group. A preliminary study revealed that successful weight losers differ from unsuccessful weight losers in valuing "wisdom" more than "happiness." Eighty-seven overweight adults were randomly assigned to one of three conditions: value self-confrontation, group discussion, or non-treatment control. Value self-confrontation subjects lost more weight than the other subjects over 2 months, and this weight loss persisted for an additional year. Changes in value priorities during the first 2 months suggest that weight loss was mediated by an increase in the importance attributed to wisdom relative to happiness. Implications for the theory of value-behavior relations and for practical application in weight loss programs are discussed.     

Effect of dichotomous thinking on the association of depression with BMI and weight change among obese females

This study tested whether a dichotomous thinking style moderates the association of depression with body mass, and investigated the effect of dichotomous thinking and depression on weight loss during a cognitive behavioural therapy (CBT) intervention.Overweight and obese females (n = 76) participated in CBT for weight management for 12 weeks. Before treatment, dichotomous thinking moderated the association of depression with BMI, such that depression was positively associated with BMI among those with low dichotomous thinking, but was not associated among those with high dichotomous thinking. Weight loss was negatively associated with pre-treatment depression and frequency of treatment attendance, but not with dichotomous thinking. Females who regard their weight as unacceptably high and who think dichotomously may experience high levels of depression irrespective of their actual weight, while depression may be proportionate to the degree of obesity among those who do not think dichotomously. Depression, but not dichotomous thinking, is likely to interfere with the ability to adhere to short-term weight loss strategies.