included RCTs. However, there was very little information available on included studies and the actual results of each
individual study was not presented. Data relating to the methods used to carry out data extraction and validity
assessment, such as the number of reviewers involved and how disagreements were resolved, were not presented. The
results of animal studies are discussed and included in the grading of evidence despite the literature search being
limited to studies on adult patients. In addition, it is not always clear how many studies (and the number of
participants) the recommendations are based on. The only electronic database searched was MEDLINE and the search
was limited to studies published in the English language and therefore important information may have been missed.
No attempt was made to locate unpublished studies and this may result in publication bias.
The author's conclusions seem to follow from the results, but in view of the above comments, should be interpreted
with caution.