Objective: To validate the attention-deficit/hyperactivity disorder (ADHD) Self-Report Scale (ASRS) v1.1 Symptom Checklist versus the clinician-administered ADHD Rating Scale (ADHD-RS) in adolescents with ADHD.
Method: A total of 88 adolescents with ADHD aged 13-17 years participated in the study. The study was completed in one or two visits, 1-9 weeks apart. At each visit, participants completed the ASRS v1.1 Symptom Checklist, after which raters administered the ADHD-RS. Internal consistency of the ASRS v1.1 Symptom Checklist was assessed by Cronbach's alpha (Cronbach's α). Concurrent validity between the scales was assessed using Pearson's correlation coefficients. Item-by-item reliability between the scales was assessed by the Kappa coefficient of agreement.
Results: The mean age of participants was 14.9±1.5 SD years. 76.1% (n=67) were male. 73.9% (n=65) were currently receiving medication for ADHD. Internal consistency of ASRS v1.1 Symptom Checklist items was high, with Cronbach's α coefficients of 0.93 at Visit 1 and 0.94 at Visit 2. Pearson's correlation coefficients between the ASRS v1.1 Symptom Checklist and ADHD-RS were highly significant at Visit 1 (r=0.72, p<0.0001) and Visit 2 (r=0.73, p<0.0001). There was moderate item-by-item agreement between individual items on the scales (% agreement: 35.2%-63.4%) with statistically significant kappa coefficients for 17 of the 18 items.
Conclusion: The ASRS v1.1 Symptoms Checklist showed high internal consistency and high concurrent validity with the clinician-administered ADHD-RS in adolescents with ADHD. Results of this study suggest that the ASRS v1.1 Symptom Checklist is an internally consistent self-report scale for the assessment of adolescent ADHD and is moderately associated with a concurrently administered clinician measure of ADHD symptoms.