Objective: To assess inter and intra rater reliability of the Thai version of Use of Alcohol and Use of Tobacco Section of the WHO Schedules for Clinical Assessment in Neuropsychiatry (SCAN).

Material and Method: Fifteen alcohol and/or tobacco dependence patients and fifteen controls with ages of ≥18 years were recruited from October 2003 to August 2004 at Srinagarind Hospital. One psychiatrist interviewed and first rated under video-recording, then re-rated two weeks later. Another psychiatrist rated independently by looking at the videotapes for inter-rater reliability testing.

Results: The intra-rater kappa was ‘excellent’ for both sections. The inter-rater kappa for all items of “tobacco use” were ‘excellent’(mean κ =0.84), and ‘good’(mean κ = 0.66) for the “alcohol use”. Items of dependence had ‘good’ kappa (mean κ = 0.73-0.95), except items of ‘activities limitation (interest neglect)’ and ‘use despite knowledge of psychological/physical problems (continued use)’ was ‘fair’ (mean κ 062-0.49). The poor kappa (mean κ = 0.17-0.38) was found in the item of ‘physical and mental health problems due to drinking’.

Conclusion: Thai SCAN provided reliable inter-rater diagnostic information for alcohol and tobacco dependence, but fair reliability for alcohol abuse. Improve understanding of the item concepts, better validity in questioning; giving examples of the focus symptoms, and frequent discussion about the respondent’s answers, might improve overall validity and reliability.

Keywords: Inter rater reliability, Intra-rater reliability, SCAN, Schedules for clinical assessment in neuropsychiatry, Alcohol use disorder, Tobacco use disorder, Validity