This study aimed to translate the revised oral assessment guide (ROAG) into Thai and modify it to improve validity and reliability for use by non-dentists. The English ROAG was translated into Thai, then revised (ndROAG), incorporating nine oral assessment categories with a three-level response system. Criterion validity was tested using 82 participants and 46 non-dentists, with a calibrated dentist as the reference standard. The ndROAG showed improved weighted Kappa (κ), intraclass correlation coefficient (ICC), and Cronbach alpha values compared to the pre-test ROAG. Sensitivity ranged from 57.1% to 100%, and specificity from 90.9% to 100%. The ndROAG offers a valid and reliable tool for non-dentists to assess oral health in adults and older individuals.
