4. Non-Pharmacological interventions
4.3 Cognitive Training
Based on the evidence reviewed in developing this guideline, cognitive training for ADHD refers largely to the use of computerised training programs to improve aspects of cognition such as attention and memory (and ultimately broader aspects of functioning as well as ADHD symptom severity).
No evidence was identified to assess effectiveness of cognitive training in this age group.
Cognitive training versus waitlist/usual care
New evidence was identified in one RCT (Bikic, Leckman, Christensen, Bilenberg, & Dalsgaard, 2018) and integrated with the NICE evidence (5 studies) resulting in 6 studies with very low- to low-certainty evidence. Findings of the pooled data across studies showed there were statistically significant benefits of cognitive training over waitlist/usual care for parent-rated ADHD inattention and hyperactivity symptoms (6 studies).
There were no statistically significant benefits of cognitive training for ADHD total symptoms (self-rated, one RCT, very low certainty; parent-rated, 3 RCTs, very low certainty; and teacher-rated, 2 RCTs, moderate certainty); teacher-rated ADHD inattention (6 studies) and hyperactivity symptoms (4 studies); parent-rated other symptoms (5 studies), and academic literacy (one study) and numeracy outcomes (one study).
One RCT (low risk of bias) reported no statistically significant differences for the Child Behaviour Checklist internalising and externalising subscales, Clinical Global Impression scale, and Children’s Global Impression scale.
Cognitive training versus non-specific supportive therapy
New evidence was identified for a new comparison consisting of a single RCT (Bikic, Christensen, Leckman, Bilenberg, & Dalsgaard, 2017) with moderate risk of bias, conducted in adolescents with ADHD, comparing cognitive training (Scientific Brain Training; SBT) and non-specific supportive therapy (the puzzle video game Tetris) over 7 weeks. There was insufficient evidence (very low certainty) to decide on the benefit of cognitive training in this group of adolescents for total ADHD symptoms, whether rated by the adolescent, parent, or teacher.
Cognitive training & behaviour parent training versus cognitive training
No new evidence was found. NICE previously identified one moderate quality RCT (Steeger, Gondoli, Gibson, & Morrissey, 2016), which compared combined child cognitive (Cogmed working memory training) and behaviour parent training with cognitive training alone. There was no clinically important benefit for parent-reported ADHD inattention, parent and teacher reported hyperactivity symptoms and other symptoms. There was a clinically important harm of intervention for teacher-reported ADHD inattention symptoms.
Cognitive training & exercise versus usual care
No new evidence was found. NICE previously identified one RCT (Smith et al., 2016) with low to moderate quality evidence. The intervention group received computerised cognitive training, exercise and a social skills game. There were no clinically important benefits for parent-reported ADHD total symptoms.
Cognitive training plus social skills versus waitlist care
New evidence was identified for a new comparison consisting of a single RCT (Lan, Liu, & Fang, 2020) with high risk of bias conducted in children with ADHD combined, comparing cognitive training plus social skills training and waitlist over 12 weeks. Raw data from this study were of very low certainty. Analysis showed that there were statistically significant benefits of the intervention for social adjustment (problems with peers), working memory, Conners’ continuous performance tasks (commission and omissions), and social skills (cooperation and empathy), but not for social adjustment (interaction with peers) or social skills (self-control). There were no statistically significant differences for ADHD symptoms (inattention and hyperactivity) or social skills (responsibility, assertion).
Cognitive training versus non-specific supportive therapy
New evidence was identified for a new comparison consisting of one RCT with moderate risk of bias and moderate certainty (Kollins et al., 2020). The RCT investigated a digital therapeutic designed to target attention and cognitive control delivered through a video game-like interface compared with a control digital device over 4 weeks. No statistically significant differences between the interventions were found for ADHD total, inattention, and hyperactivity symptoms, working memory and inhibition, impairment rating scale, and Clinician Global Impression scale.
Cognitive training versus waitlist care
No new evidence was found. NICE previously identified one study of very low quality (Virta et al., 2010). There was no clinically important benefit for quality of life, Clinical Global Impression scale or self-reported ADHD symptoms.
Cognitive training versus Non-specific supportive therapy
New evidence was identified in one RCT (Dentz, Guay, Parent, & Romo, 2020) but not integrated with the NICE evidence due to the outcome data being of low certainty and insufficiently similar to existing evidence to enable pooling. The new RCT (Dentz et al., 2020), with high risk of bias, was conducted in adults with ADHD, comparing Cogmed training and a low-intensity version of Cogmed over 5 weeks.
There were no statistically significant differences for self-reported ADHD symptoms on the Conners’ Adult ADHD Rating Scale for inattention and hyperactivity, and on the Brown Attention Deficit Disorder working memory, or executive function in daily life subscales. There were also no statistically significant differences for the Wechsler Adult Intelligence Scales III Matrix reasoning task.
NICE previously identified one RCT of low-to-moderate quality (Mawjee, Woltering, & Tannock, 2015) exploring standard Cogmed training versus a shortened version. There was no clinically important benefit for self-rated ADHD total symptoms total, functioning, academic literacy and numeracy outcomes.
Evidence to recommendation statement for cognitive training
For children and adolescents, there was no evidence to support improvements in parent-reported overall ADHD symptom severity through the delivery of cognitive training. Although there was some improvement in parent-reported inattention and hyperactivity symptoms, evidence was from studies of very low and low certainty. Furthermore, there was no robust evidence to support any improvements in parent-rated broader functioning or improved teacher-rated ADHD symptoms.
Evidence for adults suggests that there is no clear benefit of cognitive training with only 2 studies meeting inclusion criteria, both with very low to low certainty. The only clinically important findings from the two studies which were low quality were that CBT is more beneficial in comparison to cognitive training, and cognitive training may be harmful compared to waitlist.
The GDG debated whether to include a recommendation regarding cognitive training. The GDG noted the review did not identify sufficient evidence to support a recommendation of cognitive training, and there was not a body of evidence showing no effect of these interventions. The GDG agreed that further research may provide greater clarity and allow for recommendations in the future. Based on the evidence reviewed, the GDG decided to make no recommendations for cognitive training.