Chest, Vol 85, 751-758, Copyright © 1984 by American College of Chest Physicians

ARTICLES

The measurement of dyspnea. Contents, interobserver agreement, and physiologic correlates of two new clinical indexes

DA Mahler, DH Weinberg, CK Wells and AR Feinstein

To improve the clinical measurement of dyspnea, we developed a baseline dyspnea index that rated the severity of dyspnea at a single state and a transition dyspnea index that denoted changes from that baseline. The scores in both indexes depend on ratings for three different categories: functional impairment; magnitude of task, and magnitude of effort. At the baseline state, dyspnea was rated in five grades from 0 (severe) to 4 (unimpaired) for each category. The ratings for each of the three categories were added to form a baseline focal score (range, 0 to 12). At the transition period, changes in dyspnea were rated by seven grades, ranging from -3 (major deterioration), to +3 (major improvement). The ratings for each of the three categories were added to form a transition focal score (range, -9 to +9). In 38 patients tested with respiratory disease, interobserver agreement was highly satisfactory for both indexes. The baseline focal score had the highest correlation (r = 0.60; P less than 0.001) with the 12-minute walking distance (12 MW), while significant, but lower, correlations existed for lung function. For the transition focal score, there was a significant correlation only with the 12 MW (r = 0.33; p = 0.04). These results indicate that dyspnea can receive a direct clinical rating that provides important information not disclosed by customary physiologic tests.