ISEE principles for evidence synthesis and evaluation in environmental health: comments from experience on advisory and regulatory committees

Abstract

BACKGROUND AND AIM: This presentation is an individual viewpoint, but draws on my experience serving on various official committees which undertake evidence synthesis, including the UK Industrial Injuries Advisory Council, the UK Committee on Carcinogenicity, and a subcommittee of the European Food Safety Association (EFSA) Scientific Committee. METHODS: It used to be a ‘given’ that to decide whether a particular factor, either exogenous or endogenous, can cause a particular disease, and in what order of magnitude, one should consider all reasonably cogent evidence. This approach is being increasingly challenged, both scientifically and politically. The scientific challenge has come from methodologic views that focus on the randomized controlled trial (RCT) as the scientific gold standard, with priority being given, either to evidence from RCTs or to observational studies which closely mimic RCTs. The political challenge has come from various interests calling for the exclusion of epidemiological evidence from consideration by regulatory and advisory committees. This has been particularly motivated by anti-regulation “vested interests” which have disputed a long series of scientific discoveries, ranging from smoking and lung cancer to the reality of climate change. RESULTS:Recently, these pressures have led to calls for the exclusion of epidemiological evidence from consideration by regulatory and advisory committees, thereby weakening regulatory standards. This approach is typified by the (mis) use of scoring systems such as GRADE and ROBINS-I, which have been used to exclude important epidemiological evidence which does not fit the RCT paradigm. CONCLUSIONS:We need to return to a more pluralistic and inclusive approach, which considers all of the available evidence. KEYWORDS: evidence synthesis, environmental health