Integrating causation in investigative ecological weight of evidence assessments

Abstract

Weight of evidence (WOE) frameworks integrate environmental assessment data to reach conclusions regarding relative certainty of adverse environmental effects due to stressors, possible causation, and key uncertainties. Such studies can be investigative (i.e., determining whether adverse impact is occurring to identify a need for management) or retrospective (i.e., determining the cause of a detected impact such that management efforts focus on the correct stressor). Such WOE assessments do not themselves definitively establish causation; they provide the basis for subsequent follow-up studies to further investigate causation. We propose a modified investigative WOE framework that includes an additional weighting step, which we term "direction weighting." This additional step allows for the examination of alternative hypotheses and provides improved certainty regarding possible causation. To our knowledge, this approach has not been previously applied in investigative ecological WOE assessments. We provide a generic example of 2 conflicting hypotheses related to a mine discharging treated effluent to a freshwater lake: chemical toxicity versus nutrient enrichment. Integr Environ Assess Manag 2017;13:702-713. © 2016 SETAC.

Toward sustainable environmental quality: Priority research questions for Europe

“…However, as these methods evolve, care must be taken to ensure that the granularity and scale, as well as relevance and narrative intent, of different measures are properly taken into account. Field surveys and weight-of-evidence approaches alone cannot definitively establish causality (Stevenson and Chapman 2017); what is required is a combination of comprehensive field surveys (covering a wide range of stressor interactions) and experimental studies. 9.…”

Effects of atrazine on fish, amphibians, and reptiles: update of the analysis based on quantitative weight of evidence

“…The results of that exercise were published (Van Der Kraak et al 2014) and accompanied by an extensive and detailed assessment of the included studies in the Supplemental information (SI). Previous uses of the WoE framework were summarized in Van Der Kraak et al (2014) and since that time, the concept has been used or recommended in papers and by regulators conducting human and ecological risk assessments (Becker et al 2015(Becker et al , 2017Lutter et al 2015;Rhomberg 2015;Acquavella et al 2016;Agerstrand and Beronius 2016;Bridges and Solomon 2016;Brusick et al 2016;Collier et al 2016;EFSA 2017;Gross et al 2017;LaLone et al 2017;Møller and Jacobsen 2017;Stevenson and Chapman 2017;Suter et al 2017;Li et al 2019;Martin et al 2018;Rocca et al 2018;Rycroft et al 2018).…”