Reliability and validity of the Thai version of the Rapid Mood Screener (RMS-T)

by Chayanis Som-On, Chawisa Suradom, Roger S. McIntyre, Sirijit Suttajit, Suttipong Kawilapat, Sutrak Pilakanta, Manit Srisurapanont

Bipolar disorder (BD) is frequently misdiagnosed as unipolar depression, leading to inappropriate treatment and adverse outcomes. The Rapid Mood Screener (RMS) was developed to improve BD detection, a prerequisite for improving health outcomes in BD. This study aimed to translate and culturally adapt the RMS into Thai (RMS-T) and to evaluate its psychometric properties in Thai adults with bipolar I disorder (BD-I) and bipolar II disorder (BD-II).

The RMS was translated using forward–backward translation and cultural adaptation. Participants included outpatients at a tertiary psychiatric clinic with diagnosed major depressive disorder (MDD; n = 109) and BD (n = 31; BD-I = 21, BD-II = 10). Psychometric properties included internal consistency, item-total correlations, test–retest reliability, and criterion validity against the Mini International Neuropsychiatric Interview (MINI-5). Receiver operating characteristic (ROC) analyses compared RMS-T with the Thai Mood Disorder Questionnaire (T-MDQ), and optimal cutoffs were determined using Youden’s index.

Internal consistency was acceptable for a brief six-item screening tool (Cronbach’s alpha = 0.610; McDonald’s Omega = 0.632). RMS-T demonstrated good discriminative ability for BD (AUC = 0.805), comparable to T-MDQ. Optimal cutoffs were ≥ 4 for BD (sensitivity 64.5%, specificity 78.9%, Youden’s index 0.43). Test–retest reliability was strong.

The RMS-T is a valid, practical, and time-efficient screening tool for BD patients presenting with depressive episodes. Further research should investigate end-user satisfaction, the impact on health outcomes, clinical utility, and cost-effectiveness in broader settings and populations.