RESULTS
Our electronic search yielded 1183 references and our hand search three
more; after deduplication 1005 references remained. We excluded 964
references as irrelevant on title/abstract screening and assessed 41
studies for eligibility on full text. We excluded 26, listed in the
supplement with reasons. The most common reason for excluding studies on
full text was that no disaggregated numerator was reported. These
included studies that did not distinguish between serious and
non-serious ADRs, as well as studies of “umbrella topics”, such as
drug-related harm, which did not report ADRs separately. Fifteen
studies36-53 were included in this systematic review
(Figure 1).
Quality scores ranged from 1/10 (in one study) to 10/10 (in four
studies). Median [IQR] quality score was 7 [3 to 10]. All
studies clearly reported the study design (Table 1), and most also
clearly described data collection methods. In general, studies reported
using standard methods for assessing causality, preventability, and
seriousness/severity; however, details of the processes applying these
methods (for example, the people performing the assessments, solving
disagreements, etc.) were less well reported. The study characteristic
reported least often was the process of establishing seriousness.