Modelling a Multi-Dimensional Model of Memory Performance in Obsessive-Compulsive Disorder: A Multi-Level Meta-Analytic Review.
Even though memory performance is a commonly researched aspect of Obsessive-Compulsive Disorder (OCD), a coherent and unified explanation of the role of specific cognitive factors has remained elusive. To address this, the present meta-analysis examined the predictive validity of Harkin and Kessler’s (2011) Executive Function (E), Binding Complexity (B) and Memory Load (L) Classification System with regards to affected vs. unaffected memory performance in OCD. We employed a multi-level meta-analytic approach (Viechtbauer, 2010) to accommodate the interdependent nature of the EBL model and interdependency of effect sizes (305 effect sizes from 144 studies, including 4424 OCD patients). Results revealed that the EBL model predicted memory performance, i.e., as EBL demand increases, those with OCD performed progressively worse on memory tasks. Executive function was the driving mechanism behind the EBL’s impact on OCD memory performance and negated effect size differences between visual and verbal tasks in those with OCD. Comparisons of sub-task effect sizes were also generally in accord with the cognitive parameters of the EBL taxonomy. We conclude that standardised coding of tasks along individual cognitive dimensions and multi-level meta-analyses provides a new approach to examine multi-dimensional models of memory and cognitive performance in OCD and other disorders.