Treatment of chronic headache with antidepressants: a meta-analysis

CRD COMMENTARY: The research question addressed by the review was clear, though broad. There was a lack of predefined inclusion criteria, which reflected the wide scope of the review. The literature search was thorough and comprehensive, no language restrictions were placed on searches, and attempts were made to identify unpublished literature. The methodological quality of the included studies was appropriately assessed using a validated instrument, and sensitivity analyses were conducted to determine the impact of study quality on the review's findings. The methodological and participant characteristics of the primary studies were reported in detail, and further sensitivity analyses were conducted to assess their impact on the findings of the review. There appears to be a discrepancy in the numbers of primary studies focusing on different types of headache, as reported in the abstract of the review and the 'Results' section. The authors' conclusions follow clearly from the results. The limitations of this meta-analysis, in terms of the lack of available study data on the incidence of concomitant depression and the rates of use of analgesic medication, were discussed in detail by the authors.