The review addressed a clear question with well-defined inclusion criteria. The authors searched a number of relevant sources without language restrictions. Some attempts were made to locate unpublished material, which reduced the potential for publication bias. Methods used for study selection were not described, so it was impossible to rule out reviewer bias or error.
Given that the authors were able to identify only one case series, it was clear that the authors' conclusion and recommendations for further research were appropriate and likely to be reliable, despite some concerns regarding the review methodology.