Development and content validity testing of the Cardiac Symptom Survey in patients after coronary artery bypass grafting.

BACKGROUND: Patients who have undergone coronary artery bypass grafting often experience numerous symptoms after surgery. There is a need for a symptom tool for this population that is disease-specific, comprehensive, and responsive to change. AIMS: The aims of this study were to describe the development and preliminary content validity testing of the Cardiac Symptom Survey (CSS), assess further content validity of the CSS through an expert panel, and assess responsiveness of the CSS to change. METHODS: The original development of the CSS is described. An expert panel of four judges was used to rate the clarity of the items (content validity) and the relevance of the symptoms and items to the domain. Responsiveness to change of the CSS was assessed in a sample of 90 subjects who underwent coronary artery bypass grafting. RESULTS: Percent agreement and content validity index coefficients ranged from .90 to 1.00. Repeated measures analyses of variance showed significant changes over time as hypothesized in some of the symptom evaluation and symptom response scores. CONCLUSION: Support is documented for both content validity and responsiveness of the CSS.

Longitudinal field comparison of the RT3 and an activity diary with cardiac patients.

This study investigated reliability and validity of two methods of measuring patients' physical activity following coronary artery bypass graft (CABG) surgery. Sixty-five patients wore an RT3 accelerometer and recorded activity in a diary at 3 weeks, 6 weeks, and 3 months postsurgery. Generalizability coefficients greater than .80 required approximately 2 to 4 days of data, fewer than reported elsewhere. Energy expenditure estimates correlated .77, .72, and .57 (p < .01), with mean RT3 estimates higher, especially when overall energy expenditure was low. Changes from 3 to 6 weeks correlated only moderately (r = .37-.46) across methods. The methods produce reliable but differing estimates of physical activity in this population. Although no method bias is evident in assessing change over time, correlations support the importance of using multiple methods.