The Brazilian Portuguese-language version of the Manchester Respiratory Activities of Daily Living questionnaire:...

To test the construct validity, reliability, and measurement error of the Brazilian Portuguese-language version of the Manchester Respiratory Activities of Daily Living (MRADL) questionnaire in patients with COPD.

We evaluated 50 patients with COPD, among whom 30 were men, the mean age was 64 ± 8 years, and the median FEV1 as a percentage of the predicted value (FEV1%predicted) was 38.4% (interquartile range, 29.1-57.4%). Pulmonary function and limitations in activities of daily living (ADLs) were assessed by spirometry and by face-to-face application of the MRADL, respectively. For the construct validity analysis, we tested the hypothesis that the total MRADL score would show moderate correlations with spirometric parameters. We analyzed inter-rater reliability, test-retest reliability, inter-rater measurement error, and test-retest measurement error.

The total MRADL score showed moderate correlations with the FEV1/FVC ratio, FEV1 in liters, FEV1%predicted, and FVC%predicted, all of the correlations being statistically significant (r = 0.34, r = 0.31, r = 0.42, and r = 0.38, respectively; p < 0.05 for all). For the reliability and measurement error of the total MRADL score, we obtained the following inter-rater and test-retest values, respectively: two-way mixed-effects model intraclass correlation coefficient for single measures, 0.92 (95% CI: 0.87-0.96) and 0.89 (95% CI: 0.81-0.93); agreement standard error of measurement, 1.03 and 0.97; smallest detectable change at the individual level, 2.86 and 2.69; smallest detectable change at the group level, 0.40 and 0.38; and limits of agreement, -2.24 to 1.96 and -2.65 to 2.69.

In patients with COPD in Brazil, this version of the MRADL shows satisfactory construct validity, satisfactory inter-rater/test-retest reliability, and indeterminate inter-rater/test-retest measurement error.