INTRODUCTION: Poor adherence to anti-hypertensive treatment significantly contributes to the failure to achieve well-controlled blood pressure in patients with hypertension.

AIM: To convert the original English version of Medication Adherence Self-efficacy Scale (MASES) into a Persian version for clinical application in hypertensive patients.

METHODS: The backward-forward translation method was used to produce the Persian version of the questionnaire. Then the internal consistency was assessed using Cronbach's alpha. Exploratory Factor Analysis was applied to extract the components of the questionnaire. Correlation between blood pressures and drug adherence was then determined using the Persian MASES in hypertensive patients.

RESULTS: Cronbach's alpha coefficient of the Persian version of MASES was >0.92, suggesting that it can yield consistent results. Exploratory Factor Analysis suggested an uni-dimensionality of the scale. Patients with uncontrolled hypertension showed poor adherence to hypertensive medications, therefore had significant lower self-efficacy scores than those with well-controlled blood pressure by medications.

CONCLUSION: The Persian version of MASES is valid and reliable to assess self-efficacy of antihypertensive medication adherence in hypertensive patient, which is helpful to improve medication compliance in such patients in order to achieve better blood pressure controls.