Abstract
Background: Recent literature recommends a R-6MWT at begin (T0) & end (T1) of pulmonary rehabilitation (PR). This would mean considerable additional staff expense. A difference of ³10% between both 6MWTs is described as relevant. In our previous study 502 COPD patients performed a R-6MWT, with no sign. difference in mean improvement after PR (best of 2 tests vs. only first test: T0®T1: 81.3 vs. 81.7m). But 16.1%(T0) and 10.8%(T1) of patients improved relevantly in R-6MWT. This may be important in individual cases. The aim of the study was to examine if DS or patients can predict whether a R-6MWT improves relevantly.Methods: 2 6MWTs were performed at T0 & T1 of PR with an interval of 1 hour between the tests in 267 consecutive COPD patients (GOLD II-IV). After each first test a standardised questioning occurred with a 5-stage scale (“Do you think that the second test will be a least 10% better?”).Results: 49(T0) and 23(T1) of 267 patients (18.4%/8.6%) walked at R-6MWT relevantly farther. Table 1 shows further results.

Results in % at T0 and T1
 T0T1
 DSpatientDSpatient
sensitivity54.850.083.340.0
specificity71.480.551.979.2
positive predictive efficiency33.335.616.916.2
negative predictive efficiency85.888.296.492.9
 
Conclusion: While a R-6MWT seems unessential for measuring the mean improved 6MWD, it may have therapeutic consequences in individual cases. Our algorithm could be helpful in predicting relevant improvement of R-6MWD: A prediction by the DS or patients is not suitable at T0, although at T1 the DS can predict well improvement, unless the patient negates the question of improvement in the 2. test.