Minimal Detectable Change for Balance Measurements in Patients With COPD

The purpose of this study was to determine the reliability and minimal detectable change (MDC) of various outcome measures that are potentially suitable for evaluating postural control in individuals with chronic obstructive pulmonary disease (COPD).

This was a test-retest reliability study. Participants with COPD were asked to complete 5 balance assessments, separated by 1 week. The assessments included Timed Up and Go (TUG) Test, Unipodal Stance Test (UST), Tinetti Test, Berg Balance Scale (BBS), and the Activities Balance Confidence (ABC) scale. Test-retest reliability using intraclass correlation coefficients and MDC values were calculated for each assessment.

All 5 outcome measures were found to have excellent test-retest reliability (r > 0.90). The MDC95 values were 3.01 seconds and 4.03 seconds for the TUG Test and the UST, respectively; 3.23 points and 3.46 points for the Tinetti Test and the BBS, respectively; and 8.25% for the ABC scale.

The TUG, UST, BBS, the Tinetti Test, and the ABC scale are reliable outcome measures for use with people with COPD, recognizing that individual variability of performance is high. Minimal detectable change scores at the 95% CI can be used to assess change in performance over time and the impact of interventions in this population.