Validation of the Longitudinal Effect of an Integrated Nursing Intervention Based on the Integrated Theory of Health Behavior Change (ITHBC) on Multidimensional Health Indicators in Older Radiotherapy Patients.

Introduction: The Integrated Theory of Health Behavior Change (ITHBC) offers a structured framework for promoting sustained health behavior change through cognitive beliefs, self-regulation, and social facilitation. However, its application in geriatric oncology remains unexplored.

Methods: This quasi-experimental study enrolled 291 older adult patients who underwent radiotherapy at the Jiangsu Cancer Hospital. Patients hospitalized from July to December 2024 (n=146) received ITHBC-guided multidisciplinary nursing intervention, while those treated from January to June 2024 (n=145) received conventional individualized nursing care. Key outcomes, including disease cognition, self-management efficacy, and quality of life, were assessed at baseline and five months post-intervention using validated instruments. Statistical analyses included t-tests, ANCOVA, and effect-size calculations.

Results: After 5 months, the intervention group showed significantly greater improvements in disease cognition (Δ=+23.5 vs +16.4), self-management efficacy (Δ=+10.63 vs +3.77), and quality of life scores (Δ=+22.07 vs +6.98), all P < 0.001. The effect size for disease cognition was 1.32 (95% CI: 1.08-1.56).

Discussion: These findings confirm the efficacy of the ITHBC-based nursing model in enhancing cognitive, behavioral, and psychosocial outcomes in older patients undergoing radiotherapy. Structuring geriatric oncology care around behavioral theories, such as ITHBC, yields measurable benefits and supports its broader application in nursing interventions.