Development and psychometric properties of the ADHD-SCL-90-R screening scale for adult ADHD

Objective: Adult attention-deficit/hyperactivity disorder (ADHD) is a prevalent disorder with serious impairments, but it often remains undetected. The aim of the study was to develop an ADHD screening scale from the Symptom Check-List-90-R (SCL-90-R) and describe its psychometric properties. The item selection was based on the ADHD-specific Conners' Adult ADHD Rating Scale (CAARS-S:L).

Method: In total, 412 subjects of an ADHD Special Consultations Unit were investigated, who completed the SCL-90-R, CAARS-S:L, and ADHD Self-Rating Behavior Questionnaire.

Results: The ADHD-SCL-90-R Screening Scale consisted of 16 items with a four-factor structure, including Inattention/Memory Problems, Hyperactivity/Restlessness, Impulsivity/Emotional Lability, and Problems with Self-Concept. It showed excellent internal consistency (Cronbachs α = .90) and good convergent validity (r = .57-.59). Sensitivity was 78%, specificity was 56%, and the discriminatory power was acceptable (area under the curve = 0.74).

Conclusion: The newly developed ADHD-SCL-90-R Screening Scale showed good psychometric properties, and it has a versatile application in clinical practice.