Impact of a 6-month family-based weight management programme on child food and activity behaviours: short-term and long-term outcomes of the PEACH™ intervention

Background: The PEACH™ randomized controlled trial measured changes to children's food and activity behaviours following participation in a weight management programme. We have previously reported a 10% reduction in body mass index z-score at intervention end (6-month post-baseline) that was maintained to 24 months with no further intervention for the full study sample. Objectives: The objective of the study is to report changes in food and activity outcomes in the full sample at (i) the end of the 6-month intervention and (ii) 24-month post-baseline (18-month post-intervention). Methods: Changes in dietary and activity outcomes were assessed over time (baseline: n = 169, 8.1 ± 1.2 years, body mass index z-score 2.72 ± 0.62). Dietary intake was assessed using the Child Dietary Questionnaire, and times spent active and sedentary were assessed using a study-specific questionnaire. Linear mixed models were used. Results: There were significant time effects for all Child Dietary Questionnaire scores and activity and sedentary behaviours in the expected direction. Significant sex effects were observed for fruit and vegetable and sweetened beverages scores and for time spent in small screen-based activity. Conclusions: This is one of few child weight management studies to report short-term and long-term behaviour outcomes. It demonstrates that an intervention promoting food and activity behaviours consistent with guidelines can achieve modest changes, mediating improvements in relative weight.