Background & Aims: Schizophrenia is a severe psychological disorder that adversely affects the life quality of patients and their caregivers. In addition, life quality is a multidimensional and important index in determining the impact of the disease on the patient (18) and is assessed from two objective and mental aspects. It is the family of these patients who always incur the burden of support and care. Not only families must provide preliminary care (personal care and financial support) for patients, but also, they should adjust to the symptoms of the disease and accept and manage them. the Schizophrenia Caregiver Quality of Life Questionnaire encompasses significant experiences of Schizophrenia caregivers and is completely different from the conventional general quality of life questionnaires. The present study aimed to evaluate the psychometric properties of the Farsi version of the schizophrenia caregiver quality of life questionnaire (S-CGQoL).
Materials & Methods: This psychological study was conducted on all the caregivers of schizophrenia patients in Isfahan, Iran in 2018. Caregivers of schizophrenia patients were selected via continuous sampling from three mental hospitals and three nursery centers during three months and were asked to fill the S-CGQoL by Richieri et al., which was translated in the present study, and the World Health Organization Quality of Life Questionnaire (WHOQOL) (Skevington et al.). The items of this tool are scored based on a five-point Likert scale from never (score=1), to rarely (score=2), sometimes (score=3), often (score=4) and always (score=5). The S-CGQoL includes 25 items and evaluates seven dimensions of psychological and physical well-being (five items), psychological burden and daily life (seven items), relationships with spouse (three items), relationships with the psychiatric team (three items), relationships with family (two items), relationships with friends (two items) and material burden (three items). The total score is obtained from the sum of these questions, and higher scores in this questionnaire mean a higher quality of life. The tool was translated into Farsi by the translation-retranslation method. In addition, the retest reliability of the instrument was assessed by asking 40 previous participants to refill the questionnaires after two weeks. Overall, 13 out of 40 individuals returned questionnaires and 27 tools were excluded due to being incomplete. The inclusion criteria were: 1) having a family member diagnosed with schizophrenia based on DSM.5, 2) being the main caregiver of a person with schizophrenia based on interviews and being the closest relative of the patient, and 3) giving full consent to participate in the research. On the other hand, the exclusion criterion was incomplete questionnaires. Reliability was assessed by the Cronbach’s alpha method and split-half test. Following that, 200 questionnaires were distributed, 155 of which were returned. Data analysis was performed in SPSS version 24 and Amos version 21 using psychometric indexes such as confirmatory factor analysis (CFA), correlation coefficient and Cronbach’s alpha.
Results: The results of the CFA indicated significant correlations between the factorial load of all the items in the S-CGQoL with the related factor (P<0. 05) with relatively appropriate efficiency indices. Moreover, the results of internal reliability indicated the Cronbach’s alpha range of 0. 54-0. 92 in various sub-indices of the questionnaire. The results of the retest reliability showed that Pearson’s correlation coefficients for all the sub-indices of the S-CGQoL were significant in the two performed stages (P<0. 05), with the overall correlation coefficient of 0.96. In addition, the results of concurrent validity of the sub-indices of the SCGQoL with WHOQOL with the correlation-coefficient was significant (P<0.05) with a correlation coefficient of -0.56, which means that there was a strong and reverse correlation between the two instruments. According to the retest correlation coefficient results, there was a significant correlation between the scores of the first and second implementations of the S-CGQoL (P<0.01). Furthermore, the reliability of the entire S-CGQoL was approved at a Cronbach’s alpha of 0.92 and split-half of 0.78. 
Conclusion: According to the results, the Farsi version of the S-CGQoL had proper validity and reliability and could be used for the caregivers of patients with schizophrenia in the healthcare centers in Iran. Based on our findings, the overall score of the instrument with subscales of psychological and physical well-being, psychological burden and daily life, relationships with spouse, relationships with the psychiatric team, relationships with family, relationships with friends, and material burden had a favorable fit, and the questions were able to properly fit the factors related to themselves. According to the CFA and internal consistency of the S-CGQoL, the Farsi version of the instrument had construct validity and significant fit. It is suggested that the retest reliability of the tool be assessed at intervals longer than two weeks.