The relation between measures of health status and quality of life in COPD

Because quality of life (QoL) and health status (HS) scales contain different kinds of items and are shown not to be equivalent, there is a recommendation to use both types of scales. We investigated the relationship between either type of scale but focusing on the subscales of HS measures. A sample of chronic obstructive pulmonary disease (COPD) patients completed two QoL scales and two HS scales (BPQ and SGRQ), neuroticism, six-minute walk test and FEV1. Factor analysis revealed a two-factor structure (consistent with previous research), and showed that one type of HS subscale is different from QoL but another is equivalent to QoL. If total HS scores are used then it is valuable to include a QoL measure, but if HS subscales are reported, then these cover both latent variables, with the BPQ providing a clearer separation of the latent variables than the SGRQ.