ISEE principles for evidence synthesis and evaluation in environmental health. An ISEE Policy Committee symposium

Abstract

BACKGROUND AND AIM: Environmental epidemiology aims to identify environmental risk and preventive factors for health, ultimately aiming to improve public health via primary prevention by evidence informed policies aimed at modifying exposure to environmental determinants of health and via guidelines on individual behavior pertinent to environmental health. Rarely, one single study triggers strong policy measures. Therefore, evidence informed policy relies on evidence synthesis, integration and evaluation. There is a long tradition in public health with frameworks for evidence synthesis specifically developed for different subject matter domains and refined over decades in line with the developing science and methodologies pertinent to their respective fields. METHODS: Recently, there is a strong ambition from frameworks for evidence synthesis and guideline development primarily originating in clinical medicine (e. g., Cochrane, GRADE) to extend their principles and frameworks to environmental health. Building on last year’s ISEE symposium on GRADE, a task group of ISEE started to develop principles for evidence synthesis and evaluation in environmental health. RESULTS:The process of evidence synthesis and integration involves two phases. We focus here on the first phase, evidence synthesis, and specifically evidence synthesis in epidemiology. However, some of the proposed principles also apply to evidence synthesis in other fields as well to the second phase, evidence integration across different fields. The evolving principles include requirements for 1) strong subject matter expertise covering all necessary fields; 2) full transparency of the process 3) proper and transparent management of real and perceived conflicts of interest; and 4) comprehensive inclusion of pertinent studies, as judged on their scientific merit. CONCLUSIONS:The ultimate goal of this symposium is to make significant progress towards a broad consensus on principles of evidence synthesis and evaluation in environmental health that would guide future development of existing frameworks to better fit the specifics of environmental epidemiology and policy needs for environmental health. KEYWORDS: Evidence synthesis, evidence integration, causal inference