The relationship of the SF-36 health survey and the NYHA classification system in measuring functional capacity of congestive heart failure patients

Abstract

The purpose of this secondary data analysis was to investigate the relationship between two instruments frequently used to assess physical functioning capacity in persons with congestive heart failure (CHF). Functional capacity in this population predicts morbidity and is used as a guide for treatment. The New York Heart Association (NYHA) functional capacity classification and the Medical Outcome Study Short Form- 36 (SF-36) physical component, evaluate functional capacity from differing perspectives; the former is an observational tool and the latter a self-report tool. In the original study, 60 persons with documented CHF were evaluated for functional capacity using the NYHA classification and the SF-36, at hospital discharge and again in eight weeks after implementation of a weekly nurse case management intervention. It was expected in this study to find the two tools comparable in measuring physical capacity of CHF persons; including baseline measurements and change in capacity measurements. There was a statistically significant relationship showing the SF-36 physical component comparable with the NYHA functional capacity classification level in the cross sectional analysis at Time Two (F = 4.99, df = 2, :p = .01). But, the tools appeared unrelated in measuring functional capacity when magnitude of change was included in the statistical analysis.