Evaluation of the Reliability and Validity of the Persian Version of the Fatigue Assessment Scale in Iranian Sarcoidosis Patients

INTRODUCTION: Fatigue is one of the common symptoms of sarcoidosis, which occurs in about 50-70% of patients. AIM: Considering that there are no valid Iranian questionnaires for evaluating fatigue in sarcoidosis, in the present study, for the first time, we translated Fatigue Questionnaire into Persean and evaluated its validity and reliability among Iranian patients with sarcoidosis. MATERIAL AND METHODS: In methodological research, English version of Fatigue assessment scale (FAS) 10 items questionnaire which is designed to assess physical or mental fatigue in chronic disease patients, was translated into Persian and back-translated into English. Its validity and reliability were studied on the one hundred and thirteen confirmed sarcoidosis patients are referring to respiratory referral hospital of Iran. Reliability analysis was performed by estimation of Cronbach`s alpha test. RESULTS: According to the cut-off point of 22.84 (74%) of the studied patients were suffering from fatigue. The internal consistency calculation revealed that the alpha value of the physical fatigue and mental fatigue was 0.945 and 0.896, respectively. CONCLUSION: We concluded that the existence of questions number 4 and 10 in the questionnaire reduces the continuity of the questions, and therefore we suggest applying the FAS questionnaire without the two questions 4 and 10. This study showed that FAS questionnaire was very practical and can routinely be applied to assess the fatigue scale in sarcoidosis patients.