Mediating factors in dietary change: Understanding the impact of a worksite nutrition intervention

This report, based on 1,795 participants in the Next Step Trial, examines h ow a dietary intervention program affected mediating factors for dietary ch ange. The model tested whether intervention increased predisposing (skills, knowledge, and beliefs) and enabling (social support and norms) factors fo r change and advanced participants into action and maintenance stages of ch ange. The intervention significantly increased both predisposing factors fo r dietary change and the likelihood of moving into or remaining in action a nd maintenance stages of change. Changes in predisposing and enabling facto rs and stage of change at follow-up (regardless of stage at baseline) were associated with significant dietary change. Changes in mediating variables explained between 34% and 55% of the effects of the dietary intervention. T hese results support the value of measuring mediating factors as part of di etary intervention evaluations and suggest that interventions that target n orms and eating environments in addition to skills and knowledge may furthe r increase intervention effectiveness.