Reproducibility of the six-minute walk test and Glittre ADL-test in patients hospitalized for acute and exacerbated chronic lung disease

Background: The 6-minute walk test (6MWT) and the Glittre ADL-test (GT) are used to assess functional capacity and exercise tolerance; however, the reproducibility of these tests needs further study in patients with acute lung diseases. Objectives: The aim of this study was to investigate the reproducibility of the 6MWT and GT performed in patients hospitalized for acute and exacerbated chronic lung diseases. Method: 48 h after hospitalization, 81 patients (50 males, age: 52±18 years, FEV1: 58±20% of the predicted value) performed two 6MWTs and two GTs in random order on different days. Results: There was no difference between the first and second 6MWT (median 349 m [284–419] and 363 m [288–432], respectively) (ICC: 0.97; P<0.0001). A difference between the first and second tests was found in GT (median 286 s [220–378] and 244 s [197–323] respectively; P<0.001) (ICC: 0.91; P<0.0001). Conclusion: Although both the 6MWT and GT were reproducible, the best results occurred in the second test, demonstrating a learning effect. These results indicate that at least two tests are necessary to obtain reliable assessments.