We want to thank Drs Kaklamanos and Athanasiou for their letter regarding our systematic review on self-ligating appliances. We agree that including only data from randomized trials in a meta-analysis is more ideal. However, the literature on self-ligating appliances is sparse, and, for the outcome under discussion—incisor proclination—only 3 studies provided data that could be considered for analysis. One study (Scott) was an RCT; the other 2 (Jiang and Pandis) were prospective cohorts. We included Jiang’s data, even though the study was judged to have a high risk for bias. However, given the relatively low weight assigned to the article (only 5.5%), the result (statistically significant difference of 1.5 mm) was not dramatically affected by the inclusion of the data from this article. It is true that excluding Jiang’s data would have increased the I 2 from 18% to 46%. However, I 2 values less than 50% are usually considered as exhibiting moderate heterogeneity, and a fixed-effects model could be considered. If that model is used, then analysis of only Pandis’s and Scott’s data would result in the same conclusion: that there was a statistically significant difference in incisor proclination ( Fig 1 ).
