Psychological predictors of attrition in geriatric weight loss

Abstract

The present study aimed to clarify psychological factors that would discriminate between the completers and dropouts of a voluntary weight loss program. The Dietary Intervention: Evaluation of Technology (DIET) study was a community based study of older adults that, using behaviorally oriented interventions, aimed to achieve weight loss and weight maintenance, to reduce cardiovascular risk, and to reduced practitioner time. A sample of 302 subjects was dichotomized into dropouts' and "completers".;The measures used were the Brief Symptom Inventory (BSI), and the Psychological Well-Being Index (PGWB). There were no significant differences between dropouts and compliers in terms of age, sex, or any of the BSI questions, scales, or summary scores. There were a number of significant differences between the groups on individual PGWB questions, but not on the PGWB itself (the sum of the questions) or any of the subscales. Multivariate analyses were done to evaluate the combined action of the 22 PGWB questions as predictors.;Discriminant function analysis produced a model with 12 variables. This was highly significant (p = .002), and correctly classified 65% of the group as a whole, 77% of the completers, and 52% of the dropouts. Principal Components Analysis yielded a simple, interpretable three factor model. The factor scores effectively discriminated the two groups when submitted as predictors to a discriminant function analysis. One factor, which accounted for most of the total variance, reflected states of anxiety and depression. However, this did not differ between the groups. The second factor expressed issues of energy and perceived health. The third factor expressed the degree to which subjects felt in control of their emotions, thoughts and behaviors.;Completers are characterized by a lower sense of self control, but are energetic and not worried about their health. Dropouts feel firmly in control of their emotions thoughts and behaviors, but have lower levels of energy and express concerns about their health.