Comparing the use of mathematical calculation to a measuring wheel to determine distance walked in three different course configurations of the 6 minute Walk Test in healthy adults

INTRODUCTION: A recent clinical practice guideline set forth recommendations for the administration of the 6 Minute Walk Test, including course set-up and using mathematical calculation to obtain the distance walked. In clinical practice and research, however, deviations from these protocols exist. PURPOSE: To assess for differences in total distance walked between use of mathematical calculation and a measuring wheel during three different course configurations of the 6 Minute Walk Test. METHODS: Fifty healthy adults (18 males, 32 females) completed this study. The mean age was 37.04 (13.76) years ranging from 23 to 61 years. Each participant completed three course configurations of the 6 Minute Walk Test: a 12-meter straight walkway representing the Academy of Neurologic Physical Therapy Core Set of Outcome Measures Clinical Practice Guideline protocol, a 30-meter straight walkway, representing the American Thoracic Society’s recommended protocol, and a 1.2-meter by 12-meter rectangular walkway, of which the Core Set of Outcome Measures Clinical Practice Guideline was derived. For mathematical calculation, the total number of laps counted, and this total number was multiplied by the distance of one lap with any partial lap added. Additionally, a research assistant followed behind each participant with a measuring wheel to capture distance walked. RESULTS: For all configurations, there were statistically significant differences between mathematical calculation and a measuring wheel, with mathematical calculation producing significantly less total distance. Additionally, there were statistically significant differences between all course configurations, despite the method of measurement. CONCLUSION: Adhering to 6 Minute Walk Test protocols, including the method of measuring the distance, is imperative to accurately interpret results and compare to existing data. KEY MESSAGES: Despite recommendations for standardized administration of the 6 Minute Walk Test, deviations exist, including the method of which to obtain the total distance walked; either by use of mathematical calculation or a measuring wheel. In three different 6 minute walk test course configurations, including the American Thoracic Society’s recommended protocol and the Academy of Neurologic Physical Therapy recommended protocol, the measuring wheel resulted in significantly larger distances than use of the mathematical calculation. Despite the measuring wheel able to account for the turns during the 6 Minute Walk Test, it is imperative for clinicians to utilize standardized procedures such as using mathematical calculation, in order to accurately track progress and compare to existing data, of which mathematical calculation was used to derive.