A new validation of the Spanish Work Productivity and Activity Impairment Questionnaire-Crohn's disease version.

OBJECTIVES: The Work Productivity and Activity Impairment Questionnaire (WPAI) is an instrument that measures work impairment in the setting of different diseases. One previous study validating the WPAI in Crohn's disease (CD) patients suggested that its reproducibility may be unsatisfactory. This study evaluated the validity and reproducibility of the Spain Spanish version of the WPAI questionnaire in CD patients. METHODS: In a prospective study, convergent validity was tested comparing WPAI with quality of life and CD activity indices. Known-groups validity was assessed by comparing WPAI scores in CD patients with active versus inactive disease. Reproducibility of repeated tests was evaluated by comparing two WPAI measures obtained two to four weeks apart in stable patients. RESULTS: One hundred eight patients were included in the various steps of the analysis. The WPAI showed adequate known groups validity and convergent validity. The reproducibility of the test and, specifically, that of the evaluation of presenteeism (the impairment of productivity while working) were good. CONCLUSIONS: This study confirms the validity of WPAI for measuring work impairment in CD patients. In contrast to previous studies, the test reproducibility was adequate.

Validation of the Spanish Work Productivity and Activity impairment questionnaire: Crohn's disease version.

BACKGROUND: The Work Productivity and Activity Impairment questionnaire has only been partially validated in Crohn's disease. OBJECTIVE: To test the Work Productivity and Activity Impairment questionnaire for use in Crohn's disease patients. METHODS: A validated Spanish translation of the test was assessed. 'Discriminant validity' was evaluated by comparing Work Productivity and Activity Impairment scores in Crohn's disease patients with active versus inactive disease, and in patients versus healthy controls. 'Convergent validity' was tested comparing Work Productivity and Activity Impairment questionnaire with quality of life, Crohn's disease activity index and a debriefing questionnaire. 'Reproducibility' of repeated tests was evaluated by comparing two Work Productivity and Activity Impairment measures obtained 2 weeks apart in stable patients. 'Responsiveness' was determined by comparing Work Productivity and Activity Impairment values in the same patients during a flare-up of Crohn's disease and during remission. The Wilcoxon test for paired data and the Mann-Whitney U test for unpaired data were used for comparisons. RESULTS: One hundred and six patients were included in the various steps of the analysis. All Work Productivity and Activity Impairment parameters showed adequate discriminant and convergent validity and responsiveness. The test's reproducibility was also adequate, except for the evaluation of presenteeism (the impairment of productivity while working). CONCLUSION: The Spanish Work Productivity and Activity Impairment questionnaire is a valid and reliable measurement of work impairment in Crohn's disease. Unexpectedly, the test did not present satisfactory reproducibility for the evaluation of presenteeism. The reliability of this last finding should be evaluated in further studies.