Citing first publication.

In the interesting article about the pars plana clip (New World Medical, Rancho Cucamonga, CA) by Diaz Llopis et al,1 I noted that the authors attributed priority (first) publication about this device to a study published in 2006.2 We had a publication in 2005 about the pars plana clip,3 which was not cited in the references. The authors have made a useful contribution to the literature, but missed at least one article in their literature search! In general, claims for first publication should be made with caution, perhaps including the literature search protocol that was used to support such a claim.