Development and psychometric evaluation of nursing care psychological ownership scale: a sequential-exploratory mixed-method study

Psychological ownership can lead to better caring behavior. This study developed a reliable and valid Nursing Care Psychological Ownership Scale (NCPOS) to accurately measure this concept among a sample of Iranian nurses. This cross-sectional study comprised two phases: a qualitative phase (involving 13 nurses) and a quantitative phase (involving 400 nurses). Following the qualitative phase and item analysis, a 28-item NCPOS scale was developed. Exploratory Factor Analysis (EFA) extracted five factors: “Holistic Support” (7 items), “Professional Identity” (5 items), “Responsibility” (6 items), “Interactive Interaction” (6 items), and “Competence” (4 items), accounting for 42.26% of the total variance (KMO = 0.935, Bartlett’s p < 0.001). Confirmatory Factor Analysis (CFA) confirmed the five-factor model with acceptable fit indices (CMIN/DF = 2.27, RMSEA = 0.056). Convergent validity (CR, AVE), discriminant validity (HTMT), and internal consistency (Cronbach’s Alpha and McDonald’s Omega > 0.7) were confirmed. Scale stability was strong with ICC = 0.951. Analyses indicated the absence of floor and ceiling effects. The final 28-item NCPOS scale demonstrated a five-factor structure with desirable psychometric properties, including validity, reliability, stability, and the absence of floor and ceiling effects among Iranian nurses. The 28-item NCPOS scale is a valid and reliable instrument for measuring nurses’ psychological ownership of care within the Iranian nursing community.