Validation of Tools to Assess Predictors of Successful Weight Loss Outcome in Individuals With Overweight and Obesity.

OBJECTIVE

To develop and validate questionnaires to assess the behavioral, psychosocial, and environmental predictors of successful weight loss outcomes.

DESIGN

Mixed method study. Questionnaires were developed using 5 steps: item generation by literature review and preexisting questionnaires, expert evaluation, pilot testing, factor analysis, and internal consistency.

SETTING

Adults with obesity recruited via web-based survey hyperlink.

PARTICIPANTS

One hundred participants with a mean body mass index of 28.7 ± 4.4 kg/m.

VARIABLES MEASURED

The questionnaires were generated using 221 items. Establishing content, face and construct validity, and internal consistency.

ANALYSIS

Content validity was analyzed using content validity index and content validity ratio, internal consistency through Cronbach α (CA), and structural validity by factor analysis via principal varimax rotation.

RESULTS

All three questionnaires had good content validity. The Behavioral Predictor Questionnaire had good internal consistency (CA, 0.7) and excellent structural validity (69.7%). Psychosocial Predictors Questionnaire (CA, 0.8, 67.5%) and Environmental Predictors Questionnaire (CA: 0.8, 72.2%) had excellent internal consistency and structural validity.

CONCLUSION AND IMPLICATION

Questionnaires seem to be practical, valid, and reliable tools for baseline assessment of individual-specific factors related to weight loss success.