The SAFE (SGRQ score, air-flow limitation and exercise tolerance) Index: a new composite score for the stratification of severity in chronic obstructive pulmonary disease

Abstract

We have developed the SGRQ, Air-Flow limitation and Exercise tolerance Index (SAFE Index) for the stratification of severity in COPD. This index incorporates the SGRQ score, the FEV(1) % predicted and the 6 min walk distance. The SAFE Index is moderately correlated with the number of disease exacerbations.