ABSTRACT
INTRODUCTION: Brazil is a country with great climatic, socioeconomic, and cultural differences that does not yet have a reference value for the 6-min walk test (6MWT) in healthy children. To avoid misinterpretation, the use of equations to predict the maximum walk distance should be established in each country. OBJECTIVES: We sought to establish reference values and to develop an equation to predict the 6-min walk distance for healthy children in Brazil. METHODS: This is a cross-sectional multi-center study that included 1,496 healthy children, aged 7 to 12 y, assessed across 11 research sites in all regions of Brazil, and recruited from public and private schools in their respective regions. Each child was assessed for weight and height. Walk distance was our main outcome. An open-source software environment for statistical computing was used for statistical analysis. RESULTS: We observed a higher average distance walked by boys (531.1 m) than by girls (506.2 m), with a difference of 24.9 m (P < .001). We established 6MWT reference values for boys with the following equation: Distance = (16.86 × age) + (1.89 × Δ heart rate) - (0.80 × weight) + (336.91 × R1) + (360.91 × R2). For girls the equation is as follows: Distance = (13.54 × age) + (1.62 × Δ heart rate) - (1.28 × weight) + (352.33 × R1) + (394.81 × R2). CONCLUSION: Reference values were established for the 6MWT in healthy children aged 7-12 y in Brazil.
