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Solution-Focused Risk Assessment and its Challenges. Bruce K. Hope “21 st Century Environmental Risk Assessment “ SETAC ~ 33 rd Annual Meeting ~ Long Beach, CA ~ November 13, 2012. Overview. Do we have a problem or not? Finkel’s “signal of harm”
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Solution-Focused Risk Assessment and its Challenges Bruce K. Hope “21st Century Environmental Risk Assessment “ SETAC ~ 33rd Annual Meeting ~ Long Beach, CA ~ November 13, 2012
Overview • Do we have a problem or not? • Finkel’s“signal of harm” • If so, what alternatives are there for a solution? • Preferably several alternatives • Each offering a different mix of beneficial and adverse outcomes • What are the chances of these outcomes? • To choose a solution, a decision-maker needs to • Be given an impartial, unbiased assessment of each alternative • Balance chance of a beneficial versus that of an adverse outcome • Maximize “net social benefit” (including “net environmental benefit”) • Which is largely a policy choice…
Two Approaches & Three Challenges TRADITIONAL SOLUTION-FOCUSED IS IT A PROBLEM? IT’S A PROBLEM! Causal assessment Predictive assessment Adverse outcome only Threshold (hazard) methods Alternative solutions are identified {A, B, C … x} Probability of beneficial & adverse outcomes for each alternative Is there / will there be an adverse outcome? Signal of Harm? If so, solution focuses on that adverse outcome alone Decision selects alternative with greatest “net social benefit” based on more information
The Problem • How do we know that a “signal of harm” indicates a problem? • Discussion before calculation • First, agree existence (or not) of a problem, at least in principle • Negotiation, mediation, expert elicitation, workshops, etc. • Scope the source (cause) and future of agreed problem • Identify solutions and opportunities with respect to agreed problem • Save calculating for the solutions, not the problem • An affirmative role for Problem Formulation • Can be much more than just a precursor to a risk assessment
The Cause • Understanding the cause of a problem isn’t mandatory • We can just treat the symptoms, not the disease • But knowing the cause may lead to a better solution • But “cause” can too easily morph into “liability” • Implication is that “cause” will bear cost of solution • Making attribution a tall hurdle on the path to a solution • No easy answers but … • Consider cause only in context of identifying a better solution • Leave any blame / liability discussion for later • “Cause” may not be as big an issue given a good solution?
The Assessment • Worst-case, point estimate assessments will no longer be useful • Each assessment of each alternative needs to be • Complete • Full distributions of probabilities for both beneficial and adverse outcomes (i.e., “speculative” risk assessments) • Unbiased • All credible values, not just the upper-bound, high-end, no observed, etc. • Policy neutral • Exclude policy-based values; don’t set policy inside the assessment; leave that for the decision-makers • Perception + facts drive decisions, so risk communication matters