Executive function in children with neurodevelopmental conditions: a systematic review and meta-analysis

Abstract

Executive function (EF) delays are well documented in paediatric neurodevelopmental conditions (NDCs). There is no consensus about whether EF delay represents a transdiagnostic feature of NDCs. This systematic review and meta-analysis synthesized 180 studies reporting two or more NDC comparisons on EF, examined differences between NDCs, and the moderating effects of gender, age, publication year, DSM editions and assessment types. Studies using established EF measures across seven domains (attention, fluency, set-shifting, set-switching, response inhibition, planning and working memory) in participants under 18 were included. Summary effects were compared: (1) for all reported NDCs relative to control, (2) for each individual NDC relative to control and (3) between NDC groups. Results confirmed that EF delay was a transdiagnostic feature of neurodevelopmental delay, with a moderate effect size of delay across all NDCs (g = 0.56, 95% confidence interval (CI) 0.49-0.63) compared with control. This effect increased with comorbidities (g = 0.72, 95% CI 0.59-0.86), DSM-5 criteria and informant measures. Comparisons between NDCs revealed few differences: children with tic disorders (TD) showed smaller EF delays, children with attention-deficit/hyperactivity disorder (ADHD) showed larger delays in attention, response inhibition, planning and working memory compared with TD and specific learning disorders, while children with autism spectrum disorders showed greater delays on set-switching compared with ADHD. Findings support transdiagnostic models of neurodevelopment to further a developmentally sensitive science that can reveal how EF delays contribute to brain circuitry, symptom profiles and functioning, and ultimately support early interventions and outcomes for all children with NDCs.

Fig. 1. The PRISMA diagram of this systematic review.

The retrieval processes are illustrated, covering the stages of identification, screening and inclusion of studies. Note that the use of n indicates the number of studies included at each stage.

Fig. 2. Forest plot summaries overall effects (Hedges’ g) for EF in NDCs versus controls.

Here N refers to the number of studies across EF comparisons made within the meta-analysis, and k refers to the number of outcome measures reported. Mean effects and their 95% CI are presented by the central black circle and the horizontal line. The size of the black circle reflects the number of studies included in each comparison. The dashed line at g = 0 indicates no effect, while the P values show whether the effect was statistically significant. The P values reported from the random-effects models are two-sided. Source data

Fig. 3. Forest plot summaries overall effects (Hedges’ g) for each single NDC versus control.

Here N refers to the number of studies reported, and k refers to the number of outcome measures reported. Mean effects and their 95% CI are presented by the central black circle and the horizontal line. The size of the black circle reflects the number of studies included in each comparison. The dashed line at g = 0 indicates no effect, while the P values show whether the effect was statistically significant. The P values reported from the random-effects models are two-sided. FASD, fetal alcohol spectrum disorder; velo-cardio-facial syndrome (including 22q11DS), WS, fragile X syndrome (FXS), motor disorders (MD). Other group comparisons, including DS, neurofibromatosis-1, intellectual disability, Turner syndrome, communication disorders (speech, language and specific language impairments), Prader–Willi syndrome, developmental disability and prenatal alcohol exposure, were not conducted (N ≤ 2). Source data

Fig. 4. Effect sizes for seven areas of EF across NDC comparisons.

Mean effects and their 95% CI are presented by the central black circle and the horizontal line. The size of the black circle reflects the number of studies included in each comparison. The dashed line at g = 0 indicates no effect, while the P values show whether the effect was statistically significant. The P values reported from the random-effects models are two-sided. Source data