Comparing Working Memory Deficits Across ADHD and Anxiety in Youth: A Preliminary Meta-Analysis

Abstract

Although attention-deficit/hyperactivity disorder (ADHD) and anxiety disorders are conventionally treated as distinct diagnostic categories, both have been linked to working memory (WM) impairment in children and adolescents, prompting an inquiry into whether the magnitude of WM impairment may be comparable across the two conditions. This preliminary meta-analysis pooled the Hedges’ g effect sizes across six studies (four ADHD studies, two anxiety studies), comparing WM performance in youth with ADHD, clinically diagnosed anxiety, or elevated trait anxiety against comparison groups. A random effects model calculated effect for ADHD (g = 1.12, 95% CI [0.46, 1.78], p < .001) and for anxiety (g=0.69, 95% CI [0.34, 1.05], p<.001); heterogeneity was high for ADHD (I2 = 91.0%) and low for anxiety (I2 = 26.5%). A leave-one-out sensitivity analysis identified one ADHD study (Cockcroft, 2011) as the leading factor, as its exclusion lowered the ADHD estimate to g = 0.80 (95% CI [0.30, 1.29]), a value that converges closer with the anxiety estimate. The results provide support that WM impairment across ADHD and anxiety may reach a comparable magnitude; however, because the anxiety estimate rests on only two studies and the ADHD subgroup shows heterogeneity, the present analysis cannot determine whether these deficits arise from a shared processing mechanism. Future research should prioritize additional pediatric WM-anxiety studies and longitudinal designs.