Cultural Adaptation and Measurement Properties of the Iranian Version of the Families' Importance in Nursing Care—Nurses Attitudes Questionnaire Based on COSMIN Checklist: A Methodological Study

ABSTRACT Background Family involvement in nursing care is a key component of patient‐centered care and is associated with improved patient outcomes and satisfaction. However, in Iran, there is a need for a culturally adapted and psychometrically sound instrument to assess nurses' attitudes toward family involvement in care using a standardized framework. Objective To adapt and evaluate the psychometric properties of the Persian version of the Families' Importance in Nursing Care—Nurses’ Attitudes (FINC‐NA) questionnaire among Iranian nurses based on the COSMIN framework. Method This cross‐sectional methodological study was conducted among 430 nurses from Tabriz educational hospitals between January and March 2025. Participants were randomly divided into exploratory ( n = 215) and confirmatory ( n = 215) factor analysis groups. The Persian FINC‐NA was evaluated for content and face validity, construct validity (EFA and CFA), and reliability (internal consistency and test–retest reliability) following COSMIN guidelines. Data were analyzed using SPSS version 27 and AMOS version 24. Results Exploratory and confirmatory factor analyses supported a four‐factor structure of the Persian FINC‐NA: Family as an Active Care Partner, Family Engagement and Support, Family Burden, and Family Strengths and Communication. This structure explained 56.65% of the total variance and demonstrated acceptable model fit indices ( χ 2 /df = 3.63, CFI = 0.901, TLI = 0.949, RMSEA = 0.078, SRMR = 0.069). Internal consistency was acceptable for most subscales ( α ≥ 0.83), and test–retest reliability ranged from poor to good across subscales (ICC = 0.158–0.839). Conclusion The Persian version of the FINC‐NA demonstrates acceptable validity and reliability for assessing nurses' attitudes toward family involvement in nursing care in Iran. However, further refinement of certain subscales may be required to improve stability over time.