“At another website, the CGA Normative Gait Database, Kirtley (2014) shares normative gait data from several studies …”
Perhaps this sentence could be edited to avoid the possible misunderstanding that Kirtley conducted all these several studies. Might it be worth also citing the original studies from which the data is taken? This might be appropriate and feasible if you citations with numbers like [5-10].
PeerJ's citation style doesn't support the [5-10] notation so I think I'll just make the sentence clearer and not worry about citing all the studies on his webpage.
Reviewer 3 (Srinivasan):