Homeopathic prophylaxis of headaches and migraine: a systematic review

CRD COMMENTARY: The author has stated the research question and some inclusion and exclusion criteria. The literature search appears to be thorough and there were no language restrictions making it unlikely that studies have been missed. The author does not report whom, or how many reviewers, performed the selection of studies or the data extraction. There is a validity assessment of the included studies and these results were used in the discussion of the review results. The narrative discussion reported on the outcome measures and discussed methodological limitations and bias in the included studies. The author's conclusions appear to follow from the results but these should be viewed with caution because of the small number of studies and participants and limited quality of three of the four studies available.