TEST-RETEST RELIABILITY OF THE LATERAL STEP-UP TEST IN YOUNG-ADULT HEALTHY-SUBJECTS

The lateral step-up test is often utilized by clinicians to assess low er extremity performance capabilities. Reliability of the lateral step -up test, however, is not available. Therefore, the purpose of this st udy was to determine the test-retest reliability of a 15-sec and a 50- repetition lateral step-up test on a .15-m (6-inch) and .2-m (8-inch) step. For each of the 15-sec lateral step-up tests, subjects were aske d to perform as many repetitions as possible during the 15-sec time fr ame while for each of the 50-repetition lateral step-up tests, subject s were asked to perform 50 repetitions as quickly as possible. Eightee n healthy subjects were studied. Data were analyzed through a repeated measures analysis of variance, intraclass correlation coefficients (I CC) (2,1) and standard errors of measurement. The ICC values were .90 and .94 for the .15-m and .2-m 15-sec lateral step-up tests and .91 an d .96 for the .15-m and .2-m 50-repetition lateral step-lip tests, res pectively, revealing test-retest reliability to be high Tor each of th e tests. Significant differences however, were noted between the testi ng days for each or the 50-repetition lateral step-up tests, indicatin g that the measures may not be stable. No significant differences were seen between testing days for either of the 15-sec lateral step-up te sts. While the results support the use of each of the 15-sec lateral s tep-up tests as reliable, stable measures of lower extremity performan ce caution should be used when interpreting the results of either of t he M-repetition lateral step-up tests if used as demonstrated in this study.