Assessment of the Reliability of the Serbian Version of the Sickness Impact Profile Questionnaire in Patients with Chronic Viral Hepatitis.

INTRODUCTION Health-related quality of life (HRQL) of chronic patients has been researched as the ultimate goal of modern treatment of chronic diseases to improve patients'quality of life. OBJECTIVE The objective was to assess the reliability of the Serbian version of the Sickness Impact Profile (SIP) questionnaire on the sample of patients with chronic viral hepatitis. METHODS The research covered 102 patients with chronic hepatitis (47 type B and 55 type C). The assessment of the reliability of the SIP questionnaire was performed by testing the internal consistency of the questions by calculating the Cronbach's alpha coefficient. The factor analysis was used to assess whether the grouping of the questions within dimensions matches the distribution of the questions in the original English version of the questionnaire administered to U.S. patient population. RESULTS The Cronbach's alpha coefficient for the entire questionnaire is 0.925, 0.869 for the physical dimension, and 0.857 for the psychosocial dimension. After running a factor analysis of the psychosocial dimension, "emotional instability" was extracted as the key factor, confirming the results of previous research. Compared with the English version of the questionnaire, the Cronbach's alpha coefficient of the Serbian version does not diverge significantly, whereas the factor analysis confirms the classification of the questionnaire into two dimensions. CONCLUSION Our study has shown that the Serbian version of the SIP questionnaire is a reliable tool for assessing the HRQL of patients with chronic hepatitis B and C before starting treatment.