Evidence Rating Frameworks in Research

This category includes a variety of frameworks that involve rating of evidence. Examples include GRADE3 (Guyatt et al., 2011), WHO‐IARC (IARC, 2006), WCRF/AICR (2007), OSHA (2016) and guidance used to produce NTP Monographs (NTP, 2015; OHAT, 2015). Guidance to assess and integrate evidence is based on several factors, often derived from the Bradford‐Hill considerations. However, ‘Rating’ builds on the approaches of the category ‘Causal criteria’ in that more guidance is provided for appraising and integrating evidence.
These approaches usually relate to the second step of the weight of evidence process, including the appraisal of individual studies and rating confidence in the individual lines of evidence (e.g. ‘high confidence,’ ‘sufficient evidence’). Some of them also provide tools based on a matrix for integrating lines of evidence to reach hazard identification conclusions (WHO‐IARC, OHAT, OSHA (2016)). None of these approaches use formal probabilistic techniques, but it is possible to combine application of the structured framework guidance with a more quantitative presentation of conclusions.
Some of these approaches (e.g. GRADE) are designed to be flexible for use in a variety of disciplines and able to be applied under different time and resource constraints in situations corresponding to different levels of urgency (Thayer and Schünemann, 2016).
In EFSA, the scheme presented in the ‘Guidance on a harmonised framework for pest risk assessment and the identification and evaluation of pest risk management options’ (EFSA, 2010a) belongs to this category.