Impact of a Weight Management Intervention on Eating Competence: Importance of Measurement Interval in Protocol Design.

Purpose: To examine changes in eating competence (EC) in 12-month weight loss intervention.
Design: Randomized, parallel-arm with weight loss phase (baseline to month 4) and weight-maintenance phase (months 4-12).
Setting: Face-to-face in University classrooms, supervised and self-directed fitness sessions at University fitness center, and home.
Participants: Premenopausal, mostly college-educated Pennsylvania women, body mass index >25 (n = 101).
Intervention: Twenty-eight, 1-hour classes tailored for extremes of the Dietary Guidelines' fat recommendations, based on social cognitive theory, problem-based learning delivery over 12 months. Exercise component included supervised and self-directed stretching, aerobics, and strength training.
Measures: Anthropometrics, lipid profile, blood pressure, 24-hour dietary recalls, cognitive behavioral measures, Satter Eating Competence Inventory (ecSI).
Analysis: General linear model repeated measures analysis of variance for outcome variables.
Results: A total of 40% (n = 40) completed the ecSI. Overall, education and supervised exercise session attendance were 77% and 88%, respectively. Similar weight loss for lower and moderate fat groups (6.7 kg and 5.4 kg). The EC was unchanged baseline to month 4 but increased significantly from months 4 to 12, baseline to month 12 for both groups. The EC change baseline to month 12 was inversely associated with weight change from baseline to months 4 and 12.
Conclusion: Weight management interventions, likely to introduce concerns with eating attitudes, behaviors, and foods, can reduce EC. Short-term measurement of EC change captures these consequent adjustments without opportunity to regain self-efficacy. Extending the measurement interval better reflects intervention impact on EC.