Reference value for the 6-minute walk test in children and adolescents: a systematic review.

INTRODUCTION: The 6-minute walk test is a submaximal exercise test used to quantify the functional exercise capacity in clinical populations. It measures the distance walked within a period of 6-minutes. Obtaining reference values in the pediatric population is especially demanding due to factors as the development stage and age. RV provide a comparative basis for answering questions concerning the normality of health status, exercise responses and functional exercise capacity in patients. Areas covered: The aim of this review is to provide an overview of reference values and reference value prediction equations for the 6-minute walk test in the children and in adolescent pediatric population and of the methodology used to obtain them. A total of 22 studies from MEDLINE, EMBASE and Cinahl were included containing healthy participants aged ≤18 years. Reported reference values ranged from 383 m ± 41 m to 799 m ± 54 m. The prediction equation 6MWD = (4.63*height(cm))-(3.53*weight(kg))+(10.42*age)+56.32 yields the highest R2 value (0.6). Expert commentary: It is impossible to present a single best reference value. A flow-chart is presented to aid the selection of reference values or reference value prediction equations. Consensus regarding testing procedures should lead to an update and stricter application of the current guidelines.