A clinical index of disability due to chronic asthma tested during a trial of cromolyn sodium treatment.

An ordinal ranking system for clinically grading disability due to chronic asthma is described, by which to quantitate the changing course of individual patients during time-sequence observations. Experience over two years with 47 asthmatic patients undergoing various trials of disodium cromoglycate therapy indicates this index is very sensitive, reasonably reproducible in the hands of clinicians trained in its use, and specific for asthma rather than for coexisting chronic obstructive lung disease in this patient population. Duplicate scoring by trained observers is recommended. Correlations between disability and daily asthma symptom scores were generally statistically significant, but coefficients were low. Correlations of disability with pulmonary function parameters (measured fortnightly) were not significant. Statistically significant improvement was evident in most asthma indices after a month of disodium cromoglycate treatment. Disability scores improved a great deal, which implies that the observed “statistically significant” improvement in the asthma patient after disodium cromoglycate treatment represents a real clinical advantage.