Research Review: Social cognition and everyday social skills in children and adolescents with attention-deficit/hyperactivity disorder: a meta-analysis of case-control studies.

BACKGROUND: Previous studies that have assessed social cognition in Attention-Deficit/Hyperactivity Disorder (ADHD) have produced inconsistent findings. To summarize these data and shed light upon moderators that may explain observed inconsistencies, we conducted a systematic review and meta-analysis exploring social cognition (Theory of Mind (ToM), Empathy, Facial and Non-Facial Emotion Recognition) and Everyday Social Skills in children and adolescents with ADHD. METHODS: The current meta-analysis involved 142 studies including 652 effect sizes. These studies compared children and adolescents with ADHD (n = 8,300) and with typical development (n = 7,983). RESULTS: Participants with ADHD exhibited moderate to very large deficits in ToM (SMD = 0.84, 95% CI = 0.68-0.99), Facial Emotion Recognition (SMD = 0.63, 95% CI = 0.46-0.81), and Everyday Social Skills (SMD = 1.23, 95% CI = 1.08-1.37). The magnitude of these impairments was similar when considering effect sizes adjusted for some covariates and the methodological quality of the studies. Few studies have investigated Empathy and Non-Facial Emotion Recognition, which precludes definitive conclusions. CONCLUSIONS: Children and adolescents with ADHD experience robust impairments in ToM, Facial Emotion Recognition and Everyday Social Skills. Future studies should explore whether these deficits are a consequence of difficulties in other areas of cognition (e.g., executive functioning). We have made all our raw data open access to facilitate the use of the present work by the community (e.g., clinicians looking for tools, assessing social impairments, or researchers designing new studies).

Placebo effects in randomized trials of pharmacological and neurostimulation interventions for mental disorders: An umbrella review.

There is a growing literature exploring the placebo response within specific mental disorders, but no overarching quantitative synthesis of this research has analyzed evidence across mental disorders. We carried out an umbrella review of meta-analyses of randomized controlled trials (RCTs) of biological treatments (pharmacotherapy or neurostimulation) for mental disorders. We explored whether placebo effect size differs across distinct disorders, and the correlates of increased placebo effects. Based on a pre-registered protocol, we searched Medline, PsycInfo, EMBASE, and Web of Knowledge up to 23.10.2022 for systematic reviews and/or meta-analyses reporting placebo effect sizes in psychopharmacological or neurostimulation RCTs. Twenty meta-analyses, summarising 1,691 RCTs involving 261,730 patients, were included. Placebo effect size varied, and was large in alcohol use disorder (g = 0.90, 95% CI [0.70, 1.09]), depression (g = 1.10, 95% CI [1.06, 1.15]), restless legs syndrome (g = 1.41, 95% CI [1.25, 1.56]), and generalized anxiety disorder (d = 1.85, 95% CI [1.61, 2.09]). Placebo effect size was small-to-medium in obsessive-compulsive disorder (d = 0.32, 95% CI [0.22, 0.41]), primary insomnia (g = 0.35, 95% CI [0.28, 0.42]), and schizophrenia spectrum disorders (standardized mean change = 0.33, 95% CI [0.22, 0.44]). Correlates of larger placebo response in multiple mental disorders included later publication year (opposite finding for ADHD), younger age, more trial sites, larger sample size, increased baseline severity, and larger active treatment effect size. Most (18 of 20) meta-analyses were judged 'low' quality as per AMSTAR-2. Placebo effect sizes varied substantially across mental disorders. Future research should explore the sources of this variation. We identified important gaps in the literature, with no eligible systematic reviews/meta-analyses of placebo response in stress-related disorders, eating disorders, behavioural addictions, or bipolar mania.