Psychometric Evaluation of Family Illness Perceptions of Relatives with Schizophrenia

Abstract Background: Family caregivers in Taiwan significantly affect relatives with schizophrenia because Chinese culture values familial interdependence. A validated instrument is needed to examine the caregivers’ perceptions of relatives with schizophrenia. Purpose: This cross-sectional study tested the psychometric quality of the Illness Perception Questionnaire-Revised Version for Families of Patients with Schizophrenia (IPQ-RFS). Methods: Two-hundred forty primary family caregivers of outpatients with schizophrenia living in a community in central Taiwan were purposively recruited. All participants completed the IPQ-RFS and the Perceived Psychiatric Stigma Scale (PPSS). The psychometric quality of the IPQ-RFS was evaluated using internal consistency and test-retest correlations for reliability and using correlations with PPSS and exploratory factor analysis for construct validity. Results: Adequate Cronbach’s α values showed internal consistencies, and significant correlations between 3 subscales and the 4-week test-retest results of the IPQ-RFS in most subscales validated the reliability of the IPQ-RFS subscales. Exploratory factor analysis showed good construct validity and correlations with PPSS: acceptable Kaiser-Meyer-Olkin measures of sampling adequacy, Bartlett’s values, and factor loadings. Seven factors with 38 items explained 67.73% of the total variance. Conclusion: We validated the psychometric quality of the IPQ-RFS. Future studies should investigate how family caregivers’ perceptions of relatives with schizophrenia affect the treatment adherence and recovery of patients.