On 2017 Jun 18, Hilda Bastian commented:

An assessment of a critical problem, with important conclusions. It would be helpful, though, if the scope of the 4 guidelines were shown. The inclusion criteria are not very specific on this matter, and the citations of the versions of the 4 included guidelines are not provided.

In addition to the scope, the dating of the guidelines' last search for evidence (if available) with respect to the dates of the systematic reviews would be valuable. Gauging to what extent systematic reviews were not included because of being out of scope, out of date, or not yet published is important to interpreting these findings. Given how quickly systematic reviews can go out of date (Shojania KG, 2007), the non-inclusion of older systematic reviews may have been deliberate.

The publisher of the article does not appear to have uploaded Appendix A, which includes the references to the systematic reviews. Further, confusion has been created by linking the citations of the first 44 systematic reviews to the references of the article's texts. The end result is that neither the 4 guidelines nor the 71 systematic reviews are identifiable. It would be helpful if the authors would post these 75 citations here.

Disclosure: I work on PubMed Health, the PubMed resource on systematic reviews and information based on them.

On 2017 Jun 18, Hilda Bastian commented:

An assessment of a critical problem, with important conclusions. It would be helpful, though, if the scope of the 4 guidelines were shown. The inclusion criteria are not very specific on this matter, and the citations of the versions of the 4 included guidelines are not provided.

In addition to the scope, the dating of the guidelines' last search for evidence (if available) with respect to the dates of the systematic reviews would be valuable. Gauging to what extent systematic reviews were not included because of being out of scope, out of date, or not yet published is important to interpreting these findings. Given how quickly systematic reviews can go out of date (Shojania KG, 2007), the non-inclusion of older systematic reviews may have been deliberate.

The publisher of the article does not appear to have uploaded Appendix A, which includes the references to the systematic reviews. Further, confusion has been created by linking the citations of the first 44 systematic reviews to the references of the article's texts. The end result is that neither the 4 guidelines nor the 71 systematic reviews are identifiable. It would be helpful if the authors would post these 75 citations here.

Disclosure: I work on PubMed Health, the PubMed resource on systematic reviews and information based on them.