Although there was no significant difference in mean age between groups, nor in the ratio of younger to older chil- dren between groups, the proportion of children aged from 3 to 7 years was slightly higher in the hippotherapy group, which may have biased the results. Age likely affects gross motor improvements, as young children may have greater potential for improvement. Further study is needed to examine the effect of age on positive gains in hippotherapy.
Another limitation of our study is that we did not control extraneous therapeutic interventions except physical and occupational therapy. We also did not control for socioeconomic status, cognition or communication level. Each of these factors could affect PEDI scores. Further research is needed to ascertain the effect of hippotherapy on PEDI scores.