The effectiveness of the Visual Analogue Scale 8 in measuring health-related quality of life for COPD patients

The Visual Analogue Scale 8 (VAS8), consisting of eight linear scales, has been developed to measure health-related quality of life (HRQoL) in chronic obstructive pulmonary disease (COPD) patients. The purpose of this study was to examine the validity and responsiveness of the VAS8. First, HRQoL was assessed in a cross-sectional study with the VAS8 and the St George's Respiratory Questionnaire (SGRQ) in 46 COPD patients. Relationships between the VAS8 and various physiological parameters were examined. Second, in a longitudinal study, changes in HRQoL scores after pulmonary rehabilitation were evaluated in 29 COPD patients. The total VAS8 scores showed a weak correlation with vital capacity and maximal inspiratory pressure and a moderately strong correlation with 6-min walking distance and dyspnoea rating. The total VAS8 score showed a significant correlation with each SGRQ score. Furthermore, almost every VAS8 and SGRQ score improved significantly after pulmonary rehabilitation. The change in the total VAS8 value showed a strong correlation with that of the SGRQ. The VAS8 is well-suited to assess HRQoL in COPD patients. Visual analogue scales are generally useful in measuring HRQoL in COPD patients, and the VAS8 is particularly beneficial because of its ease of use.