RESUMO
BACKGROUND: It is often unclear whether systematic reviews and primary studies are de-signed to elucidate the efficacy or effectiveness of interventions. This may compromise the use of the information in clinical or policy decisions. OBJECTIVE: This overview aimed to evaluate the methodological profiles of studies on fibromyalgia pharmacotherapy in terms of the quality and nature of the interventions (efficacy versus effective-ness). METHODS: The protocol was registered in the International Prospective Register of Systematic Re-views database. Seven databases were searched for relevant publications. Systematic reviews inves-tigating the effectiveness or efficacy of fibromyalgia pharmacotherapy were included. Methodolog-ical quality was investigated using A MeaSurement Tool to Assess Systematic Reviews (AM-STAR), and efficacy andeffectiveness were evaluated using Rating of Included Trials on the Effica-cy-effectiveness Spectrum (RITES). RESULTS: In this overview, 4,107 studies were initially identified. 8 systematic reviews and 34 prima-ry studies remained after overlaps were removed. Of the eight systematic reviews, 4.76% (n=3) and 7.93% (n=5) were of moderate and high quality, respectively. An analysis of systematic reviews clearly showed the criteria "participants characteristics" and "trial setting" with the most frequent answers as scales 1 and 2 (strong emphasis on efficacy or rather strong emphasis on efficacy), re-spectively. RITES analysis revealed that the most frequent response was "strong emphasis on effi-cacy" in 68% (92/136) of primary studies. CONCLUSION: This analysis showed, in both systematic reviews and primary studies, a predominantly strong emphasis on efficacy, suggesting the need for methodological quality improvement in future studies, especially those designed to provide evidence related to effectiveness. The protocol for this overview has been registered in the International Prospective Register of Sys-tematic Reviews (PROSPERO; CRD42018095943).
