The study aims to translate and validate the generic medicine scale (GMS) among the Malaysian population. A standard “forward–backward” procedure of translation was used and the translated version was then validated on a convenience sample of 202 patients. Face validity of translated GMS was confirmed with pilot testing. Content validity of the translated GMS was evaluated by eight postgraduate students who are experts in the field. For reliability, the instrument demonstrated good internal consistency (Cronbach’s α = 0.734) with correlation coefficient ranging from 0.198 to 0.500. Alpha value for efficacy dimension of the scale was 0.623 and for similarity dimension was 0.716. The test–retest reliability of the GMS indicates good reliability and stability of the instrument with Spearman’s rank correlation coefficient of 0.532 (rs = 0.532, n = 202, p = 0.005). In conclusion, the Malaysian version of the GMS is a reliable and valid measure of patients’ belief about generic medicines.
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