Evans et al. (2021). The efficacy of cognitive video game training for ADHD and what FDA clearance means for clinicians.” – Article summary

EndeavorRX refers to a videogame-delivered cognitive training treatment intended to improve neurocognitive deficits associated with ADHD. Children play the game for 30 minutes or more every day for several weeks. The idea is that when core cognitive deficits are reduced, the problems that are associated with these deficits will also reduce. This treatment has some evidence for near-transfer but there is very limited evidence for far transfer of skills.

The hyperactive subtype of ADHD is often attributed to frontrostriatal dysfunction. It projects from the striatum to the prefrontal cortex and is involved in reward-based learning. The striatum may be under-responsive to anticipated rewards in people with the hyperactive subtype. They require larger and more immediate rewards and they habituate to rewards more quickly. In this subtype, inattention may be a secondary symptom due to low motivation as a result of frontoparietal and temporal lobe dysfunction. Next to the neural mechanisms, there are several underdeveloped neurocognitive abilities which leads to heterogeneity in ADHD (e.g. working memory deficits).

Treatment needs to improve both the neurocognitive deficiency and impairment exhibited by children with ADHD (e.g. failure to complete tasks). The outcomes thus need to generalize. Cognitive therapy may not always lead to reduced impairments in children with ADHD as it improves neurocognitive functioning but this may not generalize. Improving neurocognitive functioning may be necessary but insufficient for improvement in daily tasks (i.e. reduce impairment). Computer games may achieve far transfer which CT often fails at.

To evaluate interventions, several things are essential:

• Study design
  This refers to how a treatment is manipulated to test its efficacy.
• Outcome measures
  This refers to what is assessed (e.g. measure ADHD symptoms). The outcome measures need to take parent and child concerns into account (e.g. when the problem is not making schoolwork and the treatment improves other aspects but not this, then the treatment does not improve the right outcomes).
• Measurement timing
  This refers to when outcomes are measured.
• Magnitude of change
  This refers to the clinical significance of the change in outcome measures.

Proximal outcomes refer to measures of direct treatment targets (e.g. hypothesized maintaining factors of presenting problems). This provides valuable information about the treatment but may not directly address presenting problems. Proximal measures help in establishing underlying mechanisms of treatment and their relations to the presenting problems. However, treatment should also impact specific impairments. This is measured using impairment measures. Treatments with long-term gains as opposed to short-term improvements are preferred.

Treatments are most effective when they result in meaningful individual change on an ecologically valid outcome that is prioritized by the client and persists over time.  

CT is classified as an experimental treatment due to non-significant findings in RCTs. However, this may be due to methodological issues as most CT treatments target different neurocognitive functions while some are still intact in children with ADHD. Occasionally, there is near transfer but far transfer (e.g. improve academic achievement) is rare in CT. Attempts to improve working memory rarely translate into objective, real-world benefits. However, again, this may be due to methodological issues as other attempts to improve working memory did lead to symptom reductions, although this does not necessarily mean that it will lead to far transfer.

Behaviour management interventions for youth with ADHD involves working with parents and teachers to create optimal environments where the child can thrive. This includes clear structure and routines (1), clear expectations (2), praise for appropriate behaviours (3) and consistent consequences for rule-breaking and aggression (4). These interventions lead to improvements in ADHD symptoms and associated impairments. It is well-established for youth but probably efficacious for adolescents.

Organization skills training involves direct instruction, practice and coaching in use of new or replacement behaviours designed to address ADHD symptoms and associated impairments. Participants are taught to organize materials and time and to practice with performance feedback. The amount of practice and performance feedback and the degree to which the content of training matches real-world behaviour and domains of impairment determine efficacy of this treatment.

CT is low on the list of possible treatments that are likely to work for children and adolescents with ADHD as these two treatments (among others) work better than CT. CT has received FDA clearance but there are differences between empirical evidence that a treatment is effective and having FDA clearance. To obtain FDA clearance for a non-high-risk treatment (e.g. EndeavorRX), it needs to be demonstrated that it provides more benefits than risks while this does not mean that it is an evidence-based treatment. This means that the treatment is safe but not necessarily effective.

When a clinician discusses a requested treatment that is not supported by science (e.g. EndeavorRX), it is important to emphasize factual information about strengths, costs and limitations (1), review specific treatment goals to determine which treatments are most likely to be beneficial for the child (2) and conduct an informal analysis of goals, barriers, and availability (3).