Control beliefs as mediators between education and quality of life in patients with breast, prostate, colorectal, and lung cancer: a large register based study

Abstract

Abstract Objective Control beliefs have been found to influence adaption to a cancer diagnosis. This study explored interrelationships among education, control beliefs, and health-related quality of life (HRQoL) in patients with breast, prostate, colorectal, and lung cancer and tested weather control beliefs act as mediators. Methods Six hundred and five patients with breast (n = 205), prostate (n = 205), colorectal (n = 124), and lung (n = 71) cancer from two German cancer registries answered standardized questionnaires. Response rate was 54%. HRQoL was assessed with the EORTC QLQ-C30 core questionnaire and control beliefs (internal, external, and fatalistic) were evaluated using the IPC-questionnaire. Education was measured on a scale ranging from 1 to 8. Data were analyzed using multiple mediation models. Results There was a positive correlation between education and HRQoL. Internal beliefs were positive and external beliefs were negative correlated with HRQoL. Internal control beliefs mediated the relationship between education and global health-related quality of life (.299, CI .122, .531), physical functioning (.272, CI .110, .486), emotional functioning (.325, CI .120, .578), and pain (-.288, CI − .558, − .094). External and fatalistic control beliefs did not act as mediators. Conclusion Patients with low education feel they have less control over their cancer disease and consequently a poorer health-related quality of life.

Keywords

• Control beliefs
• Quality of life
• Cancer
• Education
• Mediation analyses