An evaluation of a body image intervention in adolescent girls delivered in single-sex versus co-educational classroom settings

Body dissatisfaction is now recognized as having considerable negative impact on social, psychological, and physical health, particularly in adolescent girls. Consequently, we have developed a six-session co-educational body image intervention (Happy Being Me Co-educational) designed to reduce body dissatisfaction and its risk factors in Grade 7 girls. In addition to evaluating the program's efficacy, we aimed to identify whether girls would benefit equally when it was delivered as a universal intervention to a whole class including both boys and girls (co-educational delivery), or delivered as a selective intervention to girls only (single-sex delivery). Participants were 200 Grade 7 girls from five schools in Melbourne, Australia. Schools were randomly allocated to receive the intervention in single-sex classes (n = 74), co-educational classes (n = 73), or participate as a no -intervention control (n = 53). Girls completed self-report assessments of body dissatisfaction, psychological (internalization of the thin ideal, appearance comparison, and self-esteem) and peer environment (weight -related teasing and appearance conversations) risk factors for body dissatisfaction, and dietary restraint, at baseline, post -intervention, and at 6-month follow-up. Significant improvements in body dissatisfaction and psychological risk factors were observed in the intervention group at post -intervention and these were maintained at follow-up for psychological risk factors. Importantly, no significant differences between universal and selective delivery were observed, suggesting that the intervention is appropriate for dissemination in both modes. (C) 2016 Elsevier Ltd. All rights reserved.