Cognitive training for attention-deficit/hyperactivity disorder: meta-analysis of clinical and neuropsychological outcomes from randomized controlled trials
Cortese S, Ferrin M, Brandeis D, Buitelaar J, Daley D, Dittmann RW, Holtmann M, Santosh P, Stevenson J, Stringaris A, Zuddas A, Sonuga-Barke EJS · 2015
grade Bmeta-analysisindependentunreplicated
Sample
16 RCTs, 759 children with ADHD
Population
Children and adolescents with ADHD
Design
The cleanest natural demonstration in this whole literature that measurement, not mechanism, drives reported benefit: the same trials are analysed twice, once using ratings by the assessor closest to the treatment (typically unblinded) and once using probably-blinded raters.
Key findings
With most-proximal (typically unblinded) raters: total ADHD SMD 0.37 (95% CI 0.09-0.66), inattention SMD 0.47 (0.14-0.80). With probably-blinded raters these fall to 0.20 (0.01-0.40) and 0.32 (-0.01 to 0.66) - i.e. inattention becomes non-significant. Laboratory working-memory measures improved (verbal SMD 0.52, visual 0.47) but effects on ACADEMIC performance were not statistically significant, and working-memory training specifically had no effect on ADHD symptoms.
Genetic confound
Low - randomised trials. The relevant bias here is rater expectancy, which blinding quantifies directly.
Effects
| Outcome | Metric | Value | Measure | Timing | Vs | Horizon | Class |
|---|---|---|---|---|---|---|---|
| Total ADHD symptoms, unblinded raters | SMD | 0.37 (95% CI 0.09-0.66) | self-report survey | post-training | unclear | end-of-treatment | behaviour |
| Total ADHD symptoms, probably-blinded raters | SMD | 0.20 (95% CI 0.01-0.40) | self-report survey | post-training | unclear | end-of-treatment | behaviour |
| Inattention, probably-blinded raters | SMD | 0.32 (95% CI -0.01 to 0.66) - non-significant | self-report survey | post-training | unclear | end-of-treatment | behaviour |
| Academic performance | SMD | not statistically significant | standardized | post-training | unclear | end-of-treatment | domain-skill |
| Laboratory working memory | SMD | verbal 0.52 (0.24-0.80); visual 0.47 (0.23-0.70) | researcher-designed | post-training | unclear | end-of-treatment | near-transfer |
Cited by
- Does working-memory or brain training transfer to intelligence and achievement?no effectconf: highgc: low