The SSADDA is a comprehensive interview used to diagnose various substance-related and other psychiatric disorders, including antisocial personality disorder (ASPD), based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria (Pierucci-Lagha et al., 2007). The SSADDA was previously translated into Thai for the study of the genetics of opioid (Malison et al., 2011) and MA dependence (Kalayasiri et al., 2014) and been previously shown to have a high inter-rater/inter-instrument reliability (Malison et al., 2011, Kalayasiri et al., 2014). Rigorous quality control (including ten practice-interviews required for each beginning interviewer prior to data collection and regular cross-editing) for the SSADDA interview was applied based on established practice with the English version in the US (Kalayasiri et al., 2014). The instruments were administered as computerized versions and performed onsite at the treatment center by a team of six interviewers, each with a bachelor's degree in psychology or higher and specifically certified in the SSADDA protocol. Half of the interviewers were psychologists employed at the treatment center (and potentially involved in the care of patients if requested by attending clinicians). Sex was identified by using data from the national identity data with no gender match between interviewers and respondents.
