GRADE: Assessing the quality of evidence in environmental and occupational health

Abstract

There is high demand in environmental health for adoption of a structured process that evaluates and integrates evidence while making decisions and recommendations transparent. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework holds promise to address this demand. For over a decade, GRADE has been applied successfully to areas of clinical medicine, public health, and health policy, but experience with GRADE in environmental and occupational health is just beginning. Environmental and occupational health questions focus on understanding whether an exposure is a potential health hazard or risk, assessing the exposure to understand the extent and magnitude of risk, and exploring interventions to mitigate exposure or risk. Although GRADE offers many advantages, including its flexibility and methodological rigor, there are features of the different sources of evidence used in environmental and occupational health that will require further consideration to assess the need for method refinement. An issue that requires particular attention is the evaluation and integration of evidence from human, animal, in vitro, and in silico (computer modelling) studies when determining whether an environmental factor represents a potential health hazard or risk. Assessment of the hazard of exposures can produce analyses for use in the GRADE evidence-to-decision (EtD) framework to inform risk-management decisions about removing harmful exposures or mitigating risks. The EtD framework allows for grading the strength of the recommendations based on judgments of the certainty in the evidence (also known as quality of the evidence), as well as other factors that inform recommendations such as social values and preferences, resource implications, and benefits. GRADE represents an untapped opportunity for environmental and occupational health to make evidence-based recommendations in a systematic and transparent manner. The objectives of this article are to provide an overview of GRADE, discuss GRADE’s applicability to environmental health, and identify priority areas for method assessment and development.

Exposure to Environmental and Occupational Particulate Air Pollution as a Potential Contributor to Neurodegeneration and Diabetes: A Systematic Review of Epidemiological Research

“…This system was developed for assessing interventions in health care contexts, and it has also been adapted to epidemiological studies [34,35]. In our case, an environmental/occupational factor or exposure can replace the clinical intervention [35].…”

Making nutrition guidelines fit for purpose

“…Such integrative approaches may be useful for complex nutrition questions such as how evolutionary changes in animal diets affect health outcomes 36. GRADE is being modified for application to environmental health topics 37. For example, some frameworks for assessing research on environmental hazards start with an initial higher rating for observational studies than GRADE would apply 38.…”

A primer on systematic reviews in toxicology

“…It remains to be seen how to determine to best adapt the GRADE approach to toxicological questions, as discussed by Morgan et al (2016), or whether an alternative system is more appropriate. In addition, further methodological discussions and case studies are needed to explore how to integrate bodies of evidence within an evidence stream and across evidence streams.

Reporting

Basic requirements

Reporting elements

Presentation of findings

…”