Reply to Jin et al.
20 December 2018 (online)
We thank Jin et al. very much for their comments regarding our paper. We appreciate their attentiveness and extensive overview of the studies, including those potentially missed in our search, which will improve research and subsequent publications.
First, Jin et al. mentioned that our search might have missed 12 studies. Indeed, two of these studies were missed: Tieu et al. 2015 (retrospective study) and Navaneethan et al. 2016 (retrospective study)  . We did find the other 10 studies, but chose to exclude them from our analysis due to publication after 1 January 2017, for example. Please see Supplemental material 1 (available online) for an overview of these studies.
Regarding the calculation methods used, we decided not to perform a meta-analysis because the studies’ populations differed in their baseline characteristics. Therefore, we feared that performing a meta-analysis would lead to a potentially false conclusion.
The authors are correct in pointing out that the complications mentioned by Alameel et al. and Chen et al. were included in the therapeutic groups despite this not being mentioned explicitly  . Draganov et al. was indeed incorrectly included in our analysis, as the results on electrohydraulic lithotripsy and laser lithotripsy were combined .
Because of the above issues, we performed an additional analysis in which we added the two missing studies  , deleted Draganov et al. , and corrected the complication rates  . However, the correction of these points did not significantly change our findings, and resulted in the same conclusion that was mentioned in our article. Please see Supplemental material 2 (available online) for this updated analysis.
Concerning the quality assessment of the studies, we used The Oxford Centre for Evidence-Based Medicine Levels of Evidence and the Newcastle – Ottawa Quality Assessment Scale for cohort studies to evaluate any risk of bias. Any doubt regarding the methodological quality assessment was discussed by two independent reviewers (J.V.V. and N.C.M.v.H.).
We completely understand that using both “bleeding” and “hemobilia” could lead to confusion when interpreting our results. We decided to adhere to the definitions used in the included articles. We opted not to interpret “bleeding” as hemobilia, as this was not specified in a number of the included studies, and we feared that this would lead to an incorrect interpretation of the results.
We would like to thank Jin et al. for these constructive suggestions. We hope that our response clarifies the questions that were raised when reading our manuscript.
* These authors contributed equally to this work.
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