Adverse Effects Not Fully Reported in 30% of Health Care Reviews

The University of York has found that potential adverse effects from health interventions, such as a drug reaction or an effect of a procedure, were not fully reported in more than one-third of published health study reviews.

Although many adverse effects can be rare and long-term, and therefore difficult to analyze as an outcome of a health intervention, researchers argue that it is imperative to fully inform medical practices, health policies, and patients of harmful adverse effects.

According to the press release, the study looked at the reporting of adverse events in 187 systematic reviews, which summarize the results and effectiveness of controlled health care interventions, published between 2017 and 2018. Research showed that 35% of reviewers did not fully report the adverse effects of the medical intervention under review.

"Despite reviewers stating in their own protocols that adverse events should be included in the review, 65% fully reported the event as intended by the protocol, 8% entirely excluded them, and the remaining 27 % either partially reported or changed the adverse event outcomes," researcher Su Golder, PhD, said in a press release.

She added, "Just over 60%, however, didn't even include adverse events in their protocols, which suggests that a more proactive approach is needed to prompt reviewers to report on potential harmful side-effects in their reporting of health care interventions."

Review authors write their own protocols to explain the steps they will follow when preparing their review of health care data, and these protocols must meet a certain criteria to be accepted for publication.

Reasons for why review authors might be missing or only partially reporting adverse effects ranged from how original studies had defined and recorded adverse events due to a lack of available space in a word-count sensitive review.

"To prevent bias in reporting of these important features of clinical trials, more work is needed to understand why so many reviewers are not fully including them and perhaps more strict guidance is needed on representing them in review protocols in the first instance," Dr Golder said.