Reliability and validity of the compliance belief scales among patients with heart failure

BACKGROUND: Lack of medication and dietary compliance leads to troublesome symptoms and hospitalization in patients with heart failure. Compliance behaviors are influenced by beliefs about the behavior. OBJECTIVE: The purpose of this study was to evaluate the reliability and validity of the Reliefs about Medication Compliance Scale (BMCS) and the Beliefs about Dietary Compliance Scale (BDCS) among patients with heart failure. THEORETICAL FRAMEWORK: This study's theoretical framework is the Health Belief Model. METHODS: A convenience sample of 234 patients with heart failure completed the BMCS and the BDCS. Patients completed the scales at baseline by face-to-face interviews and at 8 and 52 weeks after baseline by telephone interview. RESULTS: Construct validity of the scales was supported by confirmatory factor analysis. Both the BMCS and the BDCS had benefits and barriers scales with clear factor loadings. The internal consistency reliability estimates of the scales ranged from .63 to .88, with the BMCS having some estimates lower than .70. The test-retest reliability estimates ranged from .07 to .57. The intraclass correlation coefficient estimates were higher between the 8-week and 52-week scores for all scales. Possible reasons for the varying estimates are discussed. CONCLUSIONS: The BMCS and the BDCS have documented reliability and validity Future work should be directed at evaluating the responsiveness of the scales to changing patient conditions and testing interventions to improve medication and dietary compliance through chaning beliefs.