A systematic review and meta-analysis on the temporal relationship between appearance comparisons and body dissatisfaction

The co-occurrence of appearance comparison (AC) and body dissatisfaction (BD) is well-recognised, but there is no consensus on the direction of effects between the two constructs. We present findings from the first meta-analytic review of all longitudinal studies assessing the direction of effects between AC and BD. Furthermore, we provide a systematic review on studies that were not able to be included in the meta-analysis and on studies using an ecological momentary assessment (EMA) design. Systematic search following PRISMA guidelines identified 32 studies. Multilevel random-effects meta-analyses were conducted on 8 eligible studies and revealed small but significant effect sizes for the bidirectional relationship between AC and BD among women ($r_{\mathrm{AC}\to \mathrm{BD}}=$ 0.077; $r_{\mathrm{BD}\to \mathrm{AC}}=$ 0.078). Further meta-regression analyses of female data showed that these effects were not moderated by time-lag but were weakly moderated by age and body mass index. A systematic review of the remaining 24 studies (6 longitudinal; 18 EMA) revealed nuances in AC, such as direction, are important to consider as they are differentially related to BD. Nevertheless, a bidirectional relationship was supported between AC, especially upward AC, and BD. Future research should prioritize assessing the longitudinal relationship between AC and BD to clarify how these constructs influence each other over time. A more nuanced view of AC processes, along with an investigation of factors that can influence the size and direction of the AC-BD relationship, is also needed to inform targeted prevention strategies.