JMIR Publications

ABSTRACT

Background:

Recent advances in digital therapeutics (DTx) have led to the development of game-based, home-delivered interventions for children with attention-deficit/hyperactivity disorder (ADHD). Prior studies have demonstrated the feasibility and clinical potential of DTx for reducing ADHD symptoms but have primarily evaluated usage metrics, including training frequency and duration, which do not capture in-game performance or learning processes during training. In addition, the association between task difficulty regulation during DTx training and ADHD symptom improvement in children is not well studied.

Objective:

This study aimed to evaluate the clinical relevance of task difficulty regulation during DTx training in children with ADHD.

Methods:

In this study, a secondary post hoc analysis of data from 35 children aged 6–13 years with ADHD who participated in a randomized controlled trial was performed. The participants had completed a 4-week training program comprising five digital cognitive tasks from the DTx Neuro-World. During training, task difficulty was automatically adjusted in real time according to participants’ response accuracy to maintain an appropriate challenge level. Training difficulty was quantified by three indices: average task difficulty, task difficulty variability, and task difficulty slope. ADHD symptoms were assessed before and after the DTx intervention using the Korean version of the ADHD Rating Scale (K-ARS) and the Korean Child Behavior Checklist (K-CBCL). Associations between difficulty indicators and ADHD symptom changes were examined using regression analyses and group comparisons.

Results:

We found that higher average task difficulty during Tasks 1, 2, and 4 of Neuro-World was associated with improvements in ADHD symptoms as assessed by the total K-ARS score. In addition, the average task difficulty of Tasks 1–4 was positively related to improvements in hyperactivity/impulsivity symptoms of ADHD as assessed by the K-ARS hyperactivity/impulsivity sub-score but not improvements in inattention symptoms. Moreover, lower variability of task difficulty in Task 5 improved ADHD hyperactivity/impulsivity symptoms as assessed by K-ARS but did not affect K-CBCL scores. Finally, we found that a negative task difficulty slope was associated with alleviation of ADHD hyperactivity/impulsivity.

Conclusions:

Our findings suggest that improvement in ADHD symptoms are associated with maintaining optimally regulated task difficulty with an achievable range rather than reaching higher difficulty levels. Therefore, designing DTx difficulty settings to support individualized levels that enable children to perform at a consistent task difficulty may enhance the therapeutic effectiveness of DTx in reducing symptoms in children with ADHD. Clinical Trial: The Korea Clinical Research Information Service KCT0009326; https://cris.nih.go.kr/cris/search/detailSearch.do?seq=26799