Mapping meta-analyses on organochlorine pesticides reveals low methodological quality

Abstract Rachel Carson’s Silent Spring inspired a wave of research on the impacts of organochlorine pesticides, followed by a subsequent wave of meta-analyses. However, the methodological quality and content of these meta-analyses has not been evaluated. Here we systematically map and evaluate the methodological quality of 105 meta-analyses on organochlorine pesticides. We found that 83.4% of the evaluated methodological elements are low quality using the Collaboration for Environmental Evidence Synthesis Assessment Tool (CEESAT v2.1). We then reveal that 227 policy documents cited the included meta-analyses, and there is no difference in methodological quality between those that were cited in policy and those that were not. We also found a paucity of meta-analyses on wildlife despite ample primary evidence. Finally, we quantified the positive impact of using reporting guidelines and we provide recommendations for readily implementable methodological improvements.