Figure 4

Box plot of the NH (a), V _n (b), V _f (c), and AVI (d) in groups from ages two to six. The box includes observations from the 25^th to the 75^th percentile; the horizontal line within the box represents the median value, and the square represents the mean value. Lines outside the box represent the 1^th and 99^th percentiles. NH: navicular height V_n: the volume under foot arch in a sitting position V_f: the volume under foot arch in a standing position AVI: arch volume index.