Validity and Reliability of Adult ADHD Self-Report Scale Thai Version (ASRS-V1.1 TH).

Background: The adult ADHD Self-Report Scale Thai version (ASRS-V1.1) (18 items) is a questionnaire for screening adult ADHD.

Aim: To test the validity and reliability of the 18-question ASRS-V1.1 Thai version (ASRS-V1.1 TH) as a screening tool for adult ADHD.

Methods: The original 18-question ASRS-V1.1 version was translated into Thai. The process was composed of forward-translation, synthesis of the translation, and back translation. Cross cultural adaptation, field testing, and final adjustment were completed consecutively. The 18-question ASRS-V1.1 TH were sent to 1,500 parents of kindergarten and elementary school students in Bangkok, Thailand. The diagnostic interview was randomly selected for 50 parents from the positive result group and 50 parents from the negative result group. The clinical interview for confirming diagnosis was run by 3 psychiatrists who were blinded to the results and used DSM-5 ADHD criteria for diagnosis.

Results: The 18-question ASRS-V1.1 TH had satisfactory internal consistency (Cronbach's alpha = 0.92: Cronbach's alpha = 0.87 for inattentive scale, Cronbach's alpha = 0.84 for hyperactive / impulsive scale). For testing the criteria validity, the questionnaire has an adequate. The AUC from the first 6 questions was 0.80 (95% CI: 0.68-0.92) while from the 18 questions was 0.71(95% CI: 0.55-0.86).

Conclusions: The 18-question ASRS-V1.1TH is a psychometrically reliable and valid measure for screening adult ADHD in Thai clinical samples, especially the first 6 questions of the questionnaire.