Reliability and validity of ADHD diagnostic criteria in the Assessment System for Individuals with ADHD (ASIA): a Japanese semi-structured diagnostic interview.

Background: With reports of a high prevalence of attention-deficit/hyperactivity disorder (ADHD) in adults, publication of ADHD diagnostic criteria in DSM-5, and the urgent need for a relevant diagnostic instrument conforming to DSM-5, we developed the Assessment System for Individuals with ADHD (ASIA), a Japanese semi-structured diagnostic interview. We report here the reliability and validity of ASIA ADHD diagnostic criteria.
Methods: ASIA ADHD criterion A corresponds to DSM-5 ADHD criterion A and has 144 original questions assessing nine inattention symptoms and nine hyperactivity-impulsivity symptoms, each having four childhood and four adulthood questions. The 144 questions are evaluated on a 3-point frequency scale. ASIA ADHD criteria B to E correspond to DSM-5 ADHD criteria B to E and are evaluated on a 2-point scale. ASIA was administered to 60 adults (mean age, 29.9 ± 9.0 years; 28 males; 36 ADHD and 24 non-ADHD participants diagnosed by consensus of two experts).
Results: For ASIA ADHD criterion A, values of Cronbach's α for the adulthood and childhood inattention and hyperactivity-impulsivity symptoms ranged from 0.64 to 0.90. Values of κ for two independent raters ranged from 0.98 to 1.00 for the 144 questions and raw agreement rates ranged from 0.97 to 1.00 for criteria B, C, D, and E. The consensus DSM-5 diagnoses endorsed 59 of the 60 ASIA diagnoses (ADHD and non-ADHD). The ADHD group scored significantly higher on 125 of the 144 questions for criterion A than the non-ADHD group. Correlations between ASIA total and subscale scores in adulthood and corresponding scores on the Japanese version of the Conners' Adult ADHD Scales-Self Report were high.
Conclusions: ASIA ADHD criteria showed acceptable psychometric properties, although further investigation is necessary. The use of ASIA ADHD criteria could facilitate clinical practice and research into adult ADHD in Japan.