5. Searching for evidence on adverse effects


The first sources to investigate for information on adverse effects are reports from trials or other studies included in the systematic review. Excluded reports might also provide some useful information.

There are a number of specific sources of information on adverse effects of drugs, including:

In Belgium, there is currently no public database on adverse drug events. Regulatory authorities (such as the websites of FDA and EMA) and the drug manufacturer may be able to provide some information. Information on adverse effects should also be sought from other types of studies than those considered appropriate for the systematic review (e.g. cohort and case-control studies, uncontrolled [phase I and II] trials, case series and case reports). However, all such studies and reports are subject to bias to a greater extent than randomized trials, and findings must be interpreted with caution.