Shape and weight concern as a moderator of program outcomes from the Prevention Across the Spectrum RCT

Objective

To investigate if baseline shape and weight concern moderated outcomes in the Prevention Across the Spectrum trial, a randomised-controlled trial (RCT) of 3 school-based programs aimed at reducing eating disorder and obesity risk factors.

Method

N = 1,316 Grade 7 and 8 girls and boys (M age = 13.21 years) across three Australian states were randomly allocated to: Media Smart; Life Smart; Helping, Encouraging, Listening and Protecting Peers Initiative (HELPP) or control (usual school class). Risk factors were measured at baseline, post-program (5-weeks later), and 6- and 12-month follow-up.

Results

Moderation was indicated by significant interaction effects for group (Media Smart; Life Smart; HELPP; Control) X moderator (high shape and weight concern; low shape and weight concern) X time (post-program; 6-month follow-up; 12-month follow-up), with baseline entered as a covariate. Such effects were found for shape concern, weight concern, eating concern, regular eating, body dissatisfaction, and physical activity. Post-hoc testing found Media Smart participants with high baseline shape and weight concern experienced a reduction in risk at 12-month follow-up for 4 of the 6 variables.

Discussion

This study shows it is possible for a school-based program to reduce eating disorder risk factors in participants with high baseline risk of an eating disorder.