The development of a tool to assess the quality of case reports of adverse events.

About one-third of the published literature on adverse drug reactions (ADRs) and adverse events (AEs) consists of case reports. Unfortunately, the majority of case reports fall short of providing sufficient details for critical evaluation. Potentially valuable information is therefore frequently lost. The study was aimed at developing a quality assessment tool for case reports of AEs. A preliminary scale of 35 items for conventional drugs (and an additional 6 items for herbal preparations) was initially developed. Forty-eight (48) experts were invited to assess this list and modify it for face and content validity in three rounds of a Delphi process. The resulting scale of 21 items, 18 of which relates to general AEs and three items specific to herbal preparations. These items evaluate the quality of case reports in three domains: (i) drug information and therapeutic regimen (5 items); (ii) patient history, diagnosis and medications (8 items); and (iii) details of adverse events (5 items). It was tested for reliability by 16 experts using 5 randomly selected case reports. Our quality score is comprehensive and reliable. It could be an advance over existing instruments and form a basis for further developments in this area of pharmacovigilance. [ABSTRACT FROM AUTHOR]