Review of quality assessment tools for the evaluation of pharmacoepidemiological safety studies

Objectives: Pharmacoepidemiological studies are an important hypothesis-testing tool in the evaluation of postmarketing drug safety. Despite the potential to produce robust value-added data, interpretation of findings can be hindered due to well-recognised methodological limitations of these studies. Therefore, assessment of their quality is essential to evaluating their credibility. The objective of this review was to evaluate the suitability and relevance of available tools for the assessment of pharmacoepidemiological safety studies. Design: We created an a priori assessment framework consisting of reporting elements (REs) and quality assessment attributes (QAAs). A comprehensive literature search identified distinct assessment tools and the prespecified elements and attributes were evaluated. Primary and secondary outcome measures: The primary outcome measure was the percentage representation of each domain, RE and QAA for the quality assessment tools. Results: A total of 61 tools were reviewed. Most tools were not designed to evaluate pharmacoepidemiological safety studies. More than 50% of the reviewed tools considered REs under the research aims, analytical approach, outcome definition and ascertainment, study population and exposure definition and ascertainment domains. REs under the discussion and interpretation, results and study team domains were considered in less than 40% of the tools. Except for the data source domain, quality attributes were considered in less than 50% of the tools. Conclusions: Many tools failed to include critical assessment elements relevant to observational pharmacoepidemiological safety studies and did not distinguish between REs and QAAs. Further, there is a lack of considerations on the relative weights of different domains and elements. The development of a quality assessment tool would facilitate consistent, objective and evidence-based assessments of pharmacoepidemiological safety studies.