Before the data could be combined, the homogeneity ofthe effect sizes (r values) for included studies was ascertained.63 As a general test for homogeneity, the distributionsof the effect sizes of the 24 habitual gait speedstudies and 18 fast gait speed studies were examinedvisually using a stem-and-leaf display and associateddescriptive statistics. As a more definitive test for homogeneity,chi-square analyses were performed on the 2samples of effect sizes (Tab. 5).61,63,64 Nonsignificantfindings (P.10) for the chi-square analyses indicatedthat the effect sizes were sufficiently homogeneous topermit combination.Once the homogeneity of the effect sizes for the studieswas established, the effect sizes were combined using a