Psychometric Properties and Cultural Adaptation of the Persian Version of the Family Functioning Questionnaire in Rehabilitation (FFQR) in Parents of Children with Disabilities

Background: Children with special needs require extensive medical and rehabilitative interventions, which pose significant challenges for their families. The Family Functioning Questionnaire in Rehabilitation (FFQR) assesses family performance in this context. Objectives: This study aimed to evaluate the reliability, validity, and cultural adaptation of the Persian version of the FFQR among Iranian parents of children with special needs. Methods: This observational cross-sectional study focused on psychometric validation and cultural adaptation of the Persian FFQR. Rigorous evaluations of face and content validity, criterion validity, internal consistency, test-retest reliability, and construct validity were conducted. Participants included 250 parents of children aged 3 to 18 with special needs, recruited from rehabilitation facilities in Tehran province. Results: The translation process, along with assessments of face and content validity, led to adjustments in questionnaire items. The Persian version of the FFQR demonstrated excellent internal consistency (Cronbach's alpha = 0.946) and high test-retest reliability (correlation coefficient (ICC) = 0.94). However, criterion validity with the Child Adjustment and Parent Efficacy Scale-developmental disability was not established. Confirmatory factor analysis supported the original factor structure of the FFQR, affirming its cross-cultural applicability. Model fit indices indicated reasonable fit, although the chi-square test suggested an imperfect fit (χ² = 2409.03, df = 1074, P < 0.001). Conclusions: The Persian FFQR proved to be a reliable and culturally relevant tool for assessing family functioning in rehabilitation of Iranian children with special needs. These findings highlight the importance of employing culturally sensitive measurement tools in research and clinical applications.