Background: Pain management in intensive care units (ICUs) depends on nurses' knowledge, attitudes, and confidence. Whether self-efficacy accounts for part of their association with practice remains unclear.
Objectives: This study examined how ICU nurses' knowledge and attitudes relate to pain management practice through self-efficacy, using two single-mediator models (PROCESS Model 4), each adjusted for the other predictor.
Methods: This cross-sectional study included 525 ICU nurses from seven hospitals affiliated with Tehran University of Medical Sciences between April 2025 and August 2026, recruited by census. Data were collected with the McMillan knowledge and attitude questionnaires, the Persian Pain Management Self-Efficacy Questionnaire, and a 14-item practice checklist completed through observation, record review, and nurse interviews. Mediation was tested with PROCESS Model 4 in two separate single-mediator models, one for knowledge and one for attitude, adjusting for age, gender, work experience, education, and hospital.
Results: Mean (SD) scores were 18.3 (4.7) for knowledge, 56.8 (9.1) for attitude, 52.7 (12.4) for self-efficacy, and 8.4 (2.3) for practice. Indirect effects through self-efficacy were B = 0.096 (95% CI: 0.061–0.138) for knowledge and B = 0.038 (95% CI: 0.014–0.072) for attitude. Direct effects remained significant (knowledge: B = 0.222, p < 0.001; attitude: B = 0.089, p = 0.027). The full outcome model, including covariates, explained 42.1% of the variance in practice (R² = 0.421).
Conclusion: Self-efficacy showed significant indirect associations between knowledge and attitudes and pain management practice. Given the cross-sectional design, these findings indicate associations, not causal pathways; longitudinal and interventional studies are needed.