Relationship Between Test Methodology and Mean Velocity in Timed Walk Tests: A Review

Graham JE, Ostir GV, Kuo Y-F, Fisher SR, Ottenbacher KJ. Relationship between test methodology and mean velocity in timed walk tests: a review. Objective: To assess the degree to which test methodology affects outcomes in clinical evaluations of walking speed. Data Sources: Medline database and reference lists from relevant articles. Study Selection: We conducted electronic searches by using various combinations of terms related to clinical evaluations of walking speed. Resultant abstracts were then reviewed, and the methods and results section of promising full-text articles were searched for detailed descriptions of walk-test methodologies and results. Ultimately, articles were limited to the most common participant groups, older adults (aged) and individuals with neurologic conditions (neuro). The final sample included 46 studies. Data Extraction: Three aspects of test methodology (pace, starting protocol, distance timed) were extracted for use as independent variables. Group mean age was extracted for use as a covariate. Group mean velocity was extracted for use as the dependent variable. Data were extracted by a single investigator. Data Synthesis: Usual and/or comfortable pace was reported nearly twice as often as fast pace in both groups. Static-start protocols were more frequently used in aged studies, whereas dynamic (ie, rolling) starts were more common in neuro studies. Distances of 6 and 10m were most common in aged and neuro studies, respectively. Multivariate analyses (analysis of covariance) showed that only pace was significantly related to the mean velocity in both groups (aged: pace, P<.01; starting protocol, P=.21; distance, P=.05; neuro: pace, P=.01; starting protocol, P=.63; distance, P=.49). However, methodology-related differences in the distribution (95% confidence intervals) of performance scores across certain clinical standards were noted within all 3 methodology variables. Conclusions: Clinical assessments of walking velocity are not conducted uniformly. Common methodologic factors may influence the clinical interpretation of walk performances. Universal walk-test methodology is warranted to improve intergroup comparisons and the development of useful clinical criteria and consensus norms.