Objective: To assess the validity and reliability of the Montgomery and Asberg Depression Rating Scale (MADRS Thai) by comparing DSM-IV TR criteria and Hamilton Rating Scale for Depression (HRSD).
Material and method: Descriptive study. Subjects were recruited from the psychiatric out-patient clinic Siriraj Hospital. Subjects were assessed by MADRS Thai version and clinical interview.
Validity: Opinion from psychiatric and social science experts, evaluating 13 study cases and 2 7 control cases, compared to the Global Assessment Scale (GAS) and to the changed scale of HRSD.
Reliability: Inter-rater and Intra-rater reliability and Internal consistency.
Results: Content validity is above 0.5 except the item oflnner tension, Lassitude and Inablilty to feel. Criterion validity when compared to DSM-IV TR or HRSD, the sensitivity, specificity, PPV and NPV were all 100%. Pearson correlation coefficients sensitive to change were -0. 49 (p -value = 0. 11) and 0. 679 (p-value = 0. 025) when compared to 1) DSM-IV TR and 2) HRSD, respectively. ICC oflnter-rater and Intra-rater reliability were both 0.99 when compared to either 1) DSM-IV TR or 2) HRSD. Cronbach 's alpha of Internal consistency was 0. 96 and 0. 92 when compared to 1) DSM-IV TR and 2) HRSD, respectively.
Conclusion: The result suggested that the Thai version of the Montgomery and Asberg Depression Rating Scale had a very good validity and reliability. Therefore, it can be used as a diagnostic test in Thai depressed patients.