Validation of the Visual COPD Symptom Rating Questionnaire

The VSRQ was initially developed by a team of three pulmonary physicians involved in COPD management (TP, ABT, and JMG), and a specialist of HRQoL (BA), after a thorough and extensive analysis of existing generic and COPD specific questionnaires. Selection of questions was further based on two preliminary studies of questionnaires with five to eight visual analog scales.20 . Formulation of questions was further refined after ten face-to-face comprehension tests with COPD patients. Its final structure contains eight items covering dyspnea, state of anxiety, depressed mood, quality of sleep, energy, daily activities, social activities and sexual life. Each question is administered separately by the physician, through a fenestrated cardboard, and is assessed on a 10-cm long horizontal numerical rating scale that ranged from 0 to 10, with gradation lines every 1 cm; lower scores indicate higher impact on patients’ HRQoL. Labels of each extremity are specific to the item.
The VSRQ was included in a clinical trial that aimed to determine the impact of tiotropium on HRQoL in patients with mild to severe COPD, as defined by the 1995 American Thoracic Society criteria.19 (link) Patients with very severe COPD requiring long term oxygen therapy were excluded. Complete description of the criteria patients had to meet to be eligible is found in the treatment-effect article.19 (link) The study was a French multicenter, nine-month, double blind, placebo controlled-trial. Physicians administered the VSRQ and the SGRQ at screening visit (V1), baseline-visit (14 days, V2), three-month visit (V3), six- and nine-month visits. At V1, physicians also completed a case report form and established a global health assessment for each patient. Spirometric measures were performed at each visit, and included FEV₁, forced vital capacity (FVC), FEV₁/FVC and inspiratory capacity (IC).19 (link) Trial medication (tiotropium or placebo) was introduced at V2. Design and rules regarding treatment protocol during the study are fully described in the treatment-effect paper.19 (link)
Reliability and validity of the questionnaire were determined at V2, on the cross-sectional population, ie, all subjects for whom VSRQ and SGRQ questionnaires were completed at all visits, and for which at least 50% of all VSRQ and SGRQ items were filled out at V1 (Figure 1). In order to prevent a learning effect bias, the cross-sectional population was randomly split into a 2:1 ratio: 2/3 of the patients were included in the finalization step of the VSRQ (‘finalization set’ population), and 1/3 in the validation step (‘validation set’ population).21 The responsiveness of the questionnaire was assessed on the longitudinal population (patients for whom VSRQ and SGRQ were completed at V2 and V3 and were assessable, ie, at least 50% of the items completed) (Figure 1). The reproducibility was measured on patients with assessable VSRQ and SGRQ at V2 and a clinically stable status (ie, no COPD exacerbation) between V1 and V2 (Figure 1).