Objectives: The objective of the present study was to assess the reliability and validity of the Young Mania Rating Scale (YMRS) Thai Version in 76 patients with known manic symptoms. The study was carried out at Outpatient and Inpatient Departments of Psychiatry, Ramatibodhi Hospital, Bangkok, Thailand.
Material and Method: Cross–sectional study. A Thai version of the YMRS was developed through forwardbackward translation techniques and reviewed by five content-experts using psychometric methods to test the reliability and validity of the version.
Results: An eleven-item questionnaire was developed. The validity was established with the item coefficient >0.6 for all scales. The reliability of the YMRS Thai Version on a interrater test had a Pearson’s correlation of 0.87 and a Cronbach’s Alpha coefficient for all scales of >0.70. The scale’s Cronbach’s Alpha coefficient for the total number of items was 0.89.
Conclusion: The present study supports the use of the YMRS Thai Version as a valid measurement for mania in Thai patients.

Keywords: Outcome assessment, Reliability, Validity, Young Mania Rating Scale (YMRS) Thai Version, Mania