Central coherence in eating disorders: An updated systematic review and meta-analysis

Objectives. A bias towards local information over the global gist (weak central coherence, WCC), has been identified as a possible contributing and maintaining factor in eating disorders (ED). The present study aimed to provide an updated review of the WCC literature and examine the hypothesis that individuals with ED have WCC. Methods. The new search found 12 eligible studies. Meta-analyses were performed on nine of these 12 studies, the remaining three were commented on individually. Data were combined with data from the previous 2008 review, and meta-analyses were performed on 16 studies (nine studies from the new search and seven studies from 2008 review). Results. Meta-analysis of the Group Embedded Figures Task provided evidence of superior local processing across all ED subtypes (pooled effect size of d = -0.62 (95% CI = -0.94, -0.31), P < 0.001). Evidence of poorer global processing in ED groups was found from meta-analyses of the Rey-Osterrieth Complex Figures task (d = -0.63 (95% CI = -0.77, -0.49, P < 0.001), and the Object Assembly Task (d = -0.65 (95% CI = -0.94, -0.37), P < 0.0001). Conclusions. As well as supporting the results of previous studies by providing evidence of inefficient global processing, this review has provided evidence of superior local processing, which supports the WCC hypothesis in ED.