Risk Communication Qualitative Understanding Risk Perception - PDF document

Risk Communication • Qualitative Understanding Risk Perception – Aware of key aspects of risk behavior and Communication – Concepts linked sensibly • Quantitative Assessment – Accurate estimates of risks Julie S. Downs – Comparable assessments of options Department of Social and Decision Sciences Department of Social and Decision Sciences Qualitative Barriers People Simplify • People simplify • Decisions require many details • Hard to change minds • Think “safe” is all or nothing • Remember what we see • Don’t appreciate uncertainty in science • Cannot detect omissions • Good guys vs. bad guys • Disagree about what “risk” is • Easier to cope, but biased decisions Department of Social and Decision Sciences Department of Social and Decision Sciences Hard to Change Minds Remember What We See • Once people’s minds are made up, it’s • Can track events that come to our hard to change them attention • Underestimate need to seek contrary • OK if appropriate facts get through evidence • Firsthand knowledge of risks is rare • Uncertainty of negative information may • Must decipher incomplete reports be exploited – Interpreted as consistent with beliefs Department of Social and Decision Sciences Department of Social and Decision Sciences

Cannot Detect Omissions Qualitative Failures • People cannot readily detect omissions • New information may not make sense in the evidence they receive • Uncertainty may undermine beliefs • Try to account for own biases • Overconfidence may lead to insensitivity • But cannot know how much they are to new information missing • Conceptual misunderstanding can lead • Missing information may be revealed by to incorrect inferences other experiences or sources • Or it may not Department of Social and Decision Sciences Department of Social and Decision Sciences Seek Information After Risk Draw Reasoned Conclusion prior to baseline prior to baseline at baseline unsafe sex unsafe sex OR=2.15* pregnancy pregnancy infertility test test belief OR=3.28* OR=1.22* OR=2.12* condom condom misconceptions failure failure Department of Social and Decision Sciences Department of Social and Decision Sciences Act on Inferences Quantitative Barriers • Risk is hard to measure prior to baseline at baseline six months after baseline • Numbers not always intuitive • Biases in assessing one’s own risk unsafe sex OR=7.98** – Optimistic bias – Unrealistic optimism pregnancy infertility unsafe sex test belief OR=3.63* • Uncertain, delayed outcomes misconceptions (Downs, Bruine de Bruin, Murray & Fischhoff, 2004) Department of Social and Decision Sciences Department of Social and Decision Sciences

Measuring Risk Assessing Numeracy • Quantitative estimates of risk • Toss a fair coin 1,000 times – Explaining risk to people – How many times will it come up heads? – Eliciting people’s beliefs of their own risk • Chance of winning a prize is 1% • Numeracy – If 1,000 play, how many will win? – Some people are less comfortable with • Chance of winning a prize is 1 in 1,000 numbers – What percent of players win the prize? – Possible barrier to understanding risk Department of Social and Decision Sciences Department of Social and Decision Sciences Risk Perception & Numeracy Optimistic Bias • Poor numeracy impedes understanding • See less risk for ourselves – Appreciation of risk reduction • Know risk of smoking, but… • Avoiding quantitative measures reduces – Less at risk than the “typical smoker” effect of numeracy (McCoy et al., 1992) – Think they can avoid risk – Qualitative assessments (Arnett, 2000; Segerstrom et al., 1993) – Relative to other people or other conditions • Improve quantitative measures of risk Department of Social and Decision Sciences Department of Social and Decision Sciences Unrealistic Optimism Relative vs. Absolute Risk • Some who seem optimistic are realistic • Relative risk – Their health may actually be very good – Easier to measure – Some are aware of their high risk – More predictive – Optimistic bias is relative • Tie estimates to actual health • Absolute estimates – Mismatch is often optimistic – These people are particularly resistant to – More sensitive to poor numeracy efforts to change behavior – Often much, much too high (Klein, 1996) Department of Social and Decision Sciences Department of Social and Decision Sciences

Risks of Body Piercing Risks of Body Piercing 70% 70% Experience Experience 60% 60% Acquaintance 50% 50% 40% 40% 30% 30% 20% 20% 10% 10% 0% 0% Bleeding Infection Bruising Keloid Allergic Tetanus Cyst Hepatitis HIV Bleeding Infection Bruising Keloid Allergic Tetanus Cyst Hepatitis HIV Department of Social and Decision Sciences Department of Social and Decision Sciences Risks of Body Piercing Risks of Body Piercing 70% 70% Experience Experience 60% 60% Acquaintance Acquaintance Perceived risk Perceived risk 50% 50% Perceived risk (unpierced) 40% 40% 30% 30% 20% 20% 10% 10% 0% 0% Bleeding Infection Bruising Keloid Allergic Tetanus Cyst Hepatitis HIV Bleeding Infection Bruising Keloid Allergic Tetanus Cyst Hepatitis HIV (Schorzman, Gold, Murray & Downs, 2005) Department of Social and Decision Sciences Department of Social and Decision Sciences Behavior and Risk Perception Why Do We Take Risks • Risky behavior precedes lowered • Trade off costs (or risks) and benefits perception of risk – Time horizon – Experience may correct misperceptions – Probabilistic – Or may give false confidence • Conventional wisdom about risk-taking • Perceived risks go down – Risk-takers fail to appreciate risks • Perceived benefits go up – Led by perceptions of invulnerability (Fischhoff, Parker, Bruine de Bruin, Downs, Palmgren, Dawes, & Manski 2000) Department of Social and Decision Sciences Department of Social and Decision Sciences

Food Safety Mental Models Approach • Qualitative risk • Formal analysis of information from topic experts – How doe contamination occur? – Integrated assessment of the science • Quantitative risk • Compare with target audience – How likely is this food to be (un)safe? – Interviews • Relevance of past behavior – Surveys – Have I eaten this before? • Identify gaps, misconceptions, problems – Was this safe before? – How much do I value this food? Department of Social and Decision Sciences Department of Social and Decision Sciences Mental Models: Exposure Risk: General Model Integrated Assessment • Formal analysis of domain • Integrate expertise across disciplines • Apply to Decision – May refocus target for communication • Assess Existing Communications – Preliminary gauge of completeness Department of Social and Decision Sciences Department of Social and Decision Sciences Exposure Risk: Food Safety Exposure Risk: Health Department of Social and Decision Sciences Department of Social and Decision Sciences

Exposure Risk: Benefits Apply Assessment to Decision 4 Do Nothing Methylene Chloride PID (g) Breaks Only 3 Partial Complianc Full Complianc 2 Breaks + Open Open Only Breaks + Open 1 + Fan Open 0 + Fan (Riley, Fischhoff, Small & Fischbeck, 2001) (Fischhoff & Downs, 1998) Department of Social and Decision Sciences Department of Social and Decision Sciences Existing Communications Mental Models: Interviews • Qualitative information and insights 3.0 Potential Inhalation Dose (g) A, C, E – Start general 2.5 D, F – Follow up with probes 2.0 – Target specific concepts 1.5 B • Characterize knowledge in terms of the 1.0 integrated assessment 0.5 0.0 0 20 40 60 80 100 120 Time (min) (Riley, Fischhoff, Small & Fischbeck, 2001) Department of Social and Decision Sciences Department of Social and Decision Sciences Mental Models Interventions: Mental Models: Interventions Illustrating Cumulative Risk • Provide framework for understanding The first time you have 20% sex, you may or may not Chance of Contracting HIV get HIV. But the more • Avoid unnecessary repetition of prior times you have sex, the 15% more chances you have of knowledge getting it. This graph shows the chance of • New information relevant to decisions 10% getting HIV from having sex with a person who has it. The more times a • Framework to integrate additional person has sex, the more 5% chance they have of information getting HIV. This is true with or without a condom. 0% But the chances go up 0 10 20 30 40 50 60 70 80 90 100 much more quickly Exposures to HIV+ Sex Partner without a condom. Department of Social and Decision Sciences Department of Social and Decision Sciences