Comparison of Quality of Well-Being scale and NYHA functional status classification in patients with atrial fibrillation. New York Heart Association.
BACKGROUND: There is an increased need to provide appropriate outcomes evaluations. Although designed as a clinical assessment tool, the New York Heart Association (NYHA) classification is often used as an outcome measure. In this study the performance of the NYHA classification is compared with that of the Quality of Well-being scale (QWB), a standard outcome instrument. METHODS: Subjects from a clinical trial were administered both the NYHA classification and the QWB. Scores for patients with NYHA classification I, II, and III were compared by use of an ordinal regression model. RESULTS: There were significant differences in mean QWB score by NYHA classification (p < 0.0001). However, each NYHA classification score was associated with a wide range of QWB scores, limiting the potential usefulness of the NYHA classification as an outcome measure. CONCLUSIONS: The NYHA classification is not a sensitive measure of health-related quality of life, and its use as an outcome measure, although providing some insights, may result in misleading findings. The NYHA classification should not be used as the sole outcome measure.