Table 7– Reliability of incremental shuttle walk test (ISWT) distance in chronic respiratory disease
First author [ref.]DiagnosisMean age yearsSeverityMethodsICCMean difference mCoefficient of repeatabilityLeast square differences
Arnardóttir [204]COPD64Moderate to severeRepeat test 7 days later in subgroup, no practice tests, test 1 versus test 29±3874.5#
Campo [205]COPD68.6Mild to severeTest–retest, 1 week apart (practice walks performed), operators not blinded, 10 min between practice and a test0.88 (0.83–0.92)
Dyer [206]Chronic airflow limitation76Mild to moderateTest 1 versus test 3, within 2 weeks, (no practice walk on day 1), operators not blinded6±17.8935.1 m
Dyer [207]Mixed chronic lung diseases70Mild to severeRepeatability of test 1 versus test 2 (i.e. practice versus actual) on separate days23.5±47.392.7#
Eiser [7]COPD69Moderate to severeNine ISWTs performed over 3 weeks (3 tests·day−1), difference within and between days0.89Inter-subject 10 m,
intra-subject 11 m,
inter-subject variability 88.9%,
intra-subject variability 9.2%
Hill [48]COPD66.5Mild to severePractice and actual performed on same day, difference calculated as learning effect25±3568.6#
McKeough [208]COPD72Moderate to severeTest 1 versus test 2 (pre-exercise training),
test 3 versus test 4 (post-exercise training),
no practice walks
Test 1 versus 2: 20 (9–31),
test 3 versus 4: 19 (6–30)
Zainuldin [209]COPD70Mild to severeTwo tests on the same day, 30 min rest between18 (14–22)
  • Data are presented as mean±sd or value (95% CI), unless otherwise stated. ICC: intra-class correlation coefficient; COPD: chronic obstructive pulmonary disease. #: coefficient of repeatability calculated from published data as sd of differences×1.96.