The Test-Retest Reproducibility, Standard Error Measurement, and Smallest Real Difference of Dynamic Balance Tests in Chronic Stroke Survivors

Background: A dynamic balance assessment of stroke patients is a very important factor in their rehabilitation process. The aim of this study was to investigate the test-retest reproducibility and smallest real differences in the dynamic balance tests of chronic stroke survivors. Methods: This was a methodological study that fifty-three chronic stroke survivors participated in. Dynamic balance tests were performed using the figure of eight walk test, four square step test, and step test. These tests and measurements were performed twice with 1-week intervals and intra-class correlation coefficients (ICC) were used to investigate their test-retest reliability. To determine the size of the measurement error, the standard error of measurement (SEM) and smallest real difference (SRD) were used. The SEM was used to compare the test-retest reproducibility. Results: The test-retest reliability of the figure of eight walk test, four square step test, and step test was confirmed to be high, with an ICC = 0.93 similar to 0.99. The SEMs were 2.21 and 2.25 for the figure of eight walk test and four-square step test, respectively. As for the step test (paretic and non-paretic side), the SEMs were 0.68 and 0.70, respectively, which were <10% of the average score. The SRDs of the figure of eight walk test, four square step test, and step test (paretic and non-paretic side) were 6.10, 6.21, and 1.87 and 1.93, respectively. This showed a reliability of <20% of the highest score. The SRDs (%) of the figure of eight walk test, four square step test, and step test (paretic and non-paretic sides) were 28.9%, 21.9%, and 27.32% and 24.43%, respectively. The SEM for all the tests was <30% and the level of measurement error was acceptable. The ICCs of the test-retest reliability of the figure of eight walk test, four square step test, and step test were identified as high, and the test-retest reproducibility was verified by the low values of the SEM and SRD. Conclusions: The figure of eight walk test, four square step test, and step test might be useful tools for clinicians to examine the changes in dynamic balance over time in the rehabilitation of chronic stroke survivors.