On 2017 Jul 24, Joseph J Drabick commented:

Thank you for the comment for our article. We will clarify the literature searching strategy we used in the meta-analysis here. We used Pubmed, Cochrane Library, Ovid Medline and Ovid Healthstar databases, which are accessible from our medical center library. Other details for the search strategy, such as keywords, inclusion and exclusion criteria, are shown in our manuscript.

On 2017 Jul 20, Irma Klerings commented:

Remarks concerning the literature search

The authors state that they conducted the review in accordance with Cochrane guidance, which is commendable. However, both the Cochrane Handbook for Systematic Reviews of Interventions and the Methodological Expectations of Cochrane Intervention Reviews state that the full search strategies for each database need to be included in an appendix of the review.

Unfortunately, this is not the case here. As far as I can see, this article does not include a replicable search strategy in the text or in an appendix.

The description of the databases used is also puzzling: “PubMed database, Cochrane database, and Ovid database”

Ovid is not a database, but a platform that hosts many different databases. Which one(s) were used is not discernible. Similarly, it is not quite clear what is meant by “Cochrane database”. This might refer to the Cochrane Library which contains a number of databases or it might refer to only one of the databases produced by Cochrane (CDSR, CENTRAL).

In short, the authors may have adhered to Cochrane guidance when they conducted this review. But when it comes to the literature searches there is no way to tell because the reporting is insufficient. This means the reader has no way of judging the comprehensiveness and the quality of the literature search process.

On 2017 Jul 20, Irma Klerings commented:

Remarks concerning the literature search

The authors state that they conducted the review in accordance with Cochrane guidance, which is commendable. However, both the Cochrane Handbook for Systematic Reviews of Interventions and the Methodological Expectations of Cochrane Intervention Reviews state that the full search strategies for each database need to be included in an appendix of the review.

Unfortunately, this is not the case here. As far as I can see, this article does not include a replicable search strategy in the text or in an appendix.

The description of the databases used is also puzzling: “PubMed database, Cochrane database, and Ovid database”

Ovid is not a database, but a platform that hosts many different databases. Which one(s) were used is not discernible. Similarly, it is not quite clear what is meant by “Cochrane database”. This might refer to the Cochrane Library which contains a number of databases or it might refer to only one of the databases produced by Cochrane (CDSR, CENTRAL).

In short, the authors may have adhered to Cochrane guidance when they conducted this review. But when it comes to the literature searches there is no way to tell because the reporting is insufficient. This means the reader has no way of judging the comprehensiveness and the quality of the literature search process.