What number is "fifty-fifty"?: redistributing excessive 50% responses in elicited probabilities

Communicating diagnostic uncertainty reduces expectations of receiving antibiotics: Two online experiments with hypothetical patients

The overprescription of antibiotics due to diagnostic uncertainty and inappropriate patient expectations influence antimicrobial resistance. This research assesses (i) whether communicating diagnostic uncertainty reduces expectations of receiving antibiotics and (ii) which communication strategies minimise unintended consequences of such communication. In two experimental online studies conducted in January and April 2023, participants read a vignette describing a doctor consultation for an ear infection and expressed their expectations of receiving antibiotics, trust in their doctor, rated the doctor's reputation and provided their intention to get a second doctor's opinion. Study 1 (N = 2213) investigated whether communicating diagnostic uncertainty and social externalities of antibiotic use (the negative social impacts of developing antibiotic resistance) decreases expectations for antibiotics and explores potential unintended consequences on the doctor-patient relationship. In Study 2 (N = 527), we aimed to replicate and extend the findings by adding specific treatment recommendations. Disclosing diagnostic uncertainty (vs. certainty) and communicating (vs. not communicating) the social externalities of antibiotic overuse reduced patients' expectations of receiving antibiotics. Yet, communicating uncertainty impaired trust in the doctor and the doctor's reputation. Combining the communication of uncertainty with specific treatment recommendations-particularly delayed antibiotic prescriptions-showed important to prevent these unintended consequences.

Consumption and income expectations during Covid-19

Using a survey of Italian households administered in November 2021, we study the effect of microeconomic and macroeconomic expectations about the health crisis and income growth on consumption expectations in 2022. The survey elicits individual-level indicators of income and consumption expectations, distinguishing between consumption at home, away from home, online and total. We find that expected household income and expected GDP growth are strongly related to consumption expectations; income risk is positively associated with expected consumption growth for richer households. Finally, our results indicate that health-related variables were not a major drivers of consumption expectations in 2022.

Tail and Center Rounding of Probabilistic Expectations in the Health and Retirement Study

We study rounding of numerical expectations in the Health and Retirement Study (HRS) between 2002 and 2014. We document that respondent-specific rounding patterns across questions in individual waves are quite stable across waves. We discover a tendency by about half of the respondents to provide more refined responses in the tails of the 0-100 scale than the center. In contrast, only about five percent of the respondents give more refined responses in the center than the tails. We find that respondents tend to report the values 25 and 75 more frequently than other values ending in 5. We also find that rounding practices vary somewhat across question domains and respondent characteristics. We propose an inferential approach that assumes stability of response tendencies across questions and waves to infer person-specific rounding in each question domain and scale segment and that replaces each point-response with an interval representing the range of possible values of the true latent belief. Using expectations from the 2016 wave of the HRS, we validate our approach. To demonstrate the consequences of rounding on inference, we compare best-predictor estimates from face-value expectations with those implied by our intervals.

Dismissing "Don't Know" Responses to Perceived Risk Survey Items Threatens the Validity of Theoretical and Empirical Behavior-Change Research

Since the middle of the 20th century, perceptions of risk have been critical to understanding engagement in volitional behavior change. However, theoretical and empirical risk perception research seldom considers the possibility that risk perceptions do not simply exist: They must be formed. Thus, some people may not have formulated a perception of risk for a hazard at the time a researcher asks them, or they may not be confident in the extent to which their perception matches reality. We describe a decade-long research program that investigates the possibility that some people may genuinely not know their risk of even well-publicized hazards. We demonstrate that indications of not knowing (i.e., "don't know" responses) are prevalent in the U.S. population, are systematically more likely to occur among marginalized sociodemographic groups, and are associated with less engagement in protective health behaviors. "Don't know" responses are likely indications of genuinely limited knowledge and therefore may indicate populations in need of targeted intervention. This body of research suggests that not allowing participants to indicate their uncertainty may threaten the validity and generalizability of behavior-change research. We provide concrete recommendations for scientists to allow participants to express uncertainty and to analyze the resulting data.

Precise or Imprecise Probabilities? Evidence from Survey Response Related to Late-Onset Dementia

We elicit numerical expectations for late-onset dementia and long-term-care (LTC) outcomes in the US Health and Retirement Study. We provide the first empirical evidence on dementia-risk perceptions among dementia-free older Americans and establish important patterns regarding imprecision of subjective probabilities. Our elicitation distinguishes between precise and imprecise probabilities, while accounting for rounding of reports. Imprecise-probability respondents quantify imprecision using probability intervals. Nearly half of respondents hold imprecise dementia and LTC probabilities, while almost a third of precise-probability respondents round their reports. These proportions decrease substantially when LTC expectations are conditioned on hypothetical knowledge of the dementia state. Among rounding and imprecise-probability respondents, our elicitation yields two measures: an initial rounded or approximated response and a post-probe response, which we interpret as the respondent's true point or interval probability. We study the mapping between the two measures and find that respondents initially tend to over-report small probabilities and under-report large probabilities. Using a specific framework for study of LTC insurance choice with uncertain dementia state, we illustrate the dangers of ignoring imprecise or rounded probabilities for modeling and prediction of insurance demand.

Apparent age and gender differences in survival optimism: To what extent are they a bias in the translation of beliefs onto a percentage scale?

A standard way to elicit expectations asks for the percentage chance an event will occur. Previous research demonstrates noise in reported percentages. The current research models a bias; a five percentage point change in reported probabilities implies a larger change in beliefs at certain points in the probability distribution. One contribution of my model is that it can parse bias in beliefs from biases in reports. I reconsider age and gender differences in Subjective Survival Probabilities (SSPs). These are generally interpreted as differences in survival beliefs, e.g., that males are more optimistic than females and older respondents are more optimistic than younger respondents. These demographic differences (in the English Longitudinal Study of Ageing) can be entirely explained by reporting bias. Older respondents are no more optimistic than younger respondents and males are no more optimistic than females. Similarly, in forecasting, information is obscured by taking reported percentages at face value. Accounting for reporting bias thus better exploits the private information contained in reports. Relative to a face-value specification, a specification that does this delivers improved forecasts of mortality events, raising the pseudo R-squared from less than 3 percent to over 6 percent.

The informational content of subjective expectations for health service use

Background

This study aims to evaluate the informational content of people’s subjective probability expectations for using various health services.

Methods

Using a sample of 1,528 Australian adults (25-64 years), I compared stated probabilities of visiting various health service providers (hospitals, dentists, optometrists, physiotherapists and related care providers, naturopaths and massage therapists) with past utilization and with predicted utilization estimated out-of-sample. I also estimated whether past utilization and subjective expectations were predicted by the same covariates. Finally, I estimated whether subjective expectations had predictive power for the choice to purchase private health insurance conditional on past utilization and other controls.

Results

Subjective expectations closely reflect patterns of observed utilization, are predicted by the same covariates as observed utilization, and correlate with objective measures of risk. Subjective expectations also add predictive power to models estimating insurance take-up, even after conditioning on prior health care use and other risk factors.

Conclusion

The findings are indicative that on average people form quite accurate expectations, and support collecting subjective expectations about health services in household surveys for use in applied research.

Supplementary Information

The online version contains supplementary material available at (10.1186/s12913-021-06464-7).

Hesitancy Toward a COVID-19 Vaccine

The scientific community has come together in a mass mobilization to combat the public health risks of COVID-19, including efforts to develop a vaccine. However, the success of any vaccine depends on the share of the population that gets vaccinated. We designed a survey experiment in which a nationally representative sample of 3,133 adults in the USA stated their intentions to vaccinate themselves and their children for COVID-19. The factors that we varied across treatments were: the stated severity and infectiousness of COVID-19 and the stated source of the risk information (White House or the Centers for Disease Control). We find that 20% of people in the USA intend to decline the vaccine. We find no statistically significant effect on vaccine intentions from the severity of COVID-19. In contrast, we find that the degree of infectiousness of the coronavirus influences vaccine intentions and that inconsistent risk messages from public health experts and elected officials may reduce vaccine uptake. However, the most important determinants of COVID-19 vaccine hesitancy seem to be distrust of the vaccine safety (including uncertainty due to vaccine novelty), as well as general vaccine avoidance, as implied by not having had a flu shot in the last two years.

Facilitating sender-receiver agreement in communicated probabilities: Is it best to use words, numbers or both?

Organizations tasked with communicating expert judgments couched in uncertainty often use numerically bounded linguistic probability schemes to standardize the meaning of verbal probabilities. An experiment (N = 1,202) was conducted to ascertain whether agreement with such a scheme was better when probabilities were presented verbally, numerically or in a combined “verbal + numeric” format. Across three agreement measures, the numeric and combined formats outperformed the verbal format and also yielded better discrimination between low and high probabilities and were less susceptible to the fifty-fifty blip phenomenon. The combined format did not confer any advantage over the purely numeric format. The findings indicate that numerically bounded linguistic probability schemes are an ineffective means of communicating information about probabilities to others and they call into question recommendations for use of the combined format for delivering such schemes.

Beliefs and Risk Perceptions About COVID-19: Evidence From Two Successive French Representative Surveys During Lockdown

BACKGROUND

The outbreak of COVID-19 has been a major interrupting event, challenging how societies and individuals deal with risk. An essential determinant of the virus' spread is a series of individual decisions, such as wearing face masks in public space. Those decisions depend on trade-offs between costs (or benefits) and risks, and beliefs are key to explain these.

METHODS

We elicit beliefs about the COVID-19 pandemic during lockdown in France by means of surveys asking French citizens about their belief of the infection fatality ratio (IFR) for COVID-19, own risk to catch the disease, risk as perceived by others, and expected prevalence rate. Those self-assessments were measured twice during lockdown: about 2 weeks after lockdown started and about 2 weeks before lockdown ended. We also measured the quality of these beliefs with respect to available evidence at the time of the surveys, allowing us to assess the calibration of beliefs based on risk-related socio-demographics. Finally, comparing own risk to expected prevalence rates in the two successive surveys provides a dynamic view of comparative optimism with respect to the disease.

RESULTS

The risk perceptions are rather high in absolute terms and they increased between the two surveys. We found no evidence for an impact of personal experience with COVID-19 on beliefs and lower risk perceptions of the IFR when someone in the respondent's family has been diagnosed with a disease. Answers to survey 1 confirmed this pattern with a clear indication that respondents were optimistic about their chances to catch COVID-19. However, in survey 2, respondents revealed comparative pessimism.

CONCLUSION

The results show that respondents overestimated the probabilities to catch or die from COVID-19, which is not unusual and does not necessarily reflect a strong deviation from rational behavior. While a rational model explains why the own risk to catch COVID-19 rose between the two surveys, it does not explain why the subjective assessment of the IFR remained stable. The comparative pessimism in survey 2 was likely due to a concomitant increase in the respondents' perceived chances to catch the disease and a decreased expected prevalence rate.

Risk Perceptions and Flood Insurance: Insights from Homeowners on the Georgia Coast

Scholars highlight a wide array of factors that can influence individual decision-making under risk. Utilizing survey data, we explore many potential factors that affect risk perception and protective behaviors. Our focus is on coastal Georgia, which has lower historical risk relative to the rest of the Southeast U.S., and which many people perceive as relatively safe, but was recently adversely affected by two major storms. The results indicate a majority of coastal residents expect coastal storms and other hazards to be worse in the future. The regression results suggest perceived damages, risk tolerance, wealth exposure, and flood zone are robust determinants of flood insurance purchase. Other factors, like flood zone awareness and attitudes towards community risk management initiatives—like shoreline armoring, beach replenishment, and coastal retreat—are also indicated to have a high correlation with flood insurance purchase.

Improving Probability Judgment in Intelligence Analysis: From Structured Analysis to Statistical Aggregation

As in other areas of expert judgment, intelligence analysis often requires judging the probability that hypotheses are true. Intelligence organizations promote the use of structured methods such as "Analysis of Competing Hypotheses" (ACH) to improve judgment accuracy and analytic rigor, but these methods have received little empirical testing. In this experiment, we pitted ACH against a factorized Bayes's theorem (FBT) method, and we examined the value of recalibration (coherentization) and aggregation methods for improving the accuracy of probability judgment. Analytic techniques such as ACH and FBT were ineffective in improving accuracy and handling correlated evidence, and ACH in fact decreased the coherence of probability judgments. In contrast, statistical postanalytic methods (i.e., coherentization and aggregation) yielded large accuracy gains. A wide range of methods for instantiating these techniques were tested. The interactions among the factors considered suggest that prescriptive theorists and interventionists should examine the value of ensembles of judgment-support methods.

A configural model of expert judgement as a preliminary epidemiological study of injury problems: An application to drowning

Robust epidemiological studies identifying determinants of negative health outcomes require significant research effort. Expert judgement is proposed as an efficient alternative or preliminary research design for risk factor identification associated with unintentional injury. This proposition was tested in a multi-factorial balanced experimental design using specialist judges (N = 18), lifeguards and surfers, to assess the risk contribution to drowning for swimming ability, surf bathing experience, and wave height. All factors provided unique contributions to drowning risk (p < .001). An interaction (p = .02) indicated that occasional surf bathers face a proportionally increased risk of drowning at increased wave heights relative to experienced surf bathers. Although findings were limited by strict criteria, and no gold standard comparison data were available, the study provides new evidence on causal risk factors for a drowning scenario. Countermeasures based on these factors are proposed. Further application of the method may assist in developing new interventions to reduce unintentional injury.

Using NCI-Designated Cancer Center Catchment-Area Data to Understand an Ignored but High-Need Constituent: People Uncertain or Avoidant about Their Cancer Risk

In 2016, the NCI provided supplemental funding to 15 NCI-designated cancer centers to enhance cancer centers' capacity to collect critical catchment-area data across behavioral and psychosocial domains [March 2019 issue of Cancer Epidemiology, Biomarkers & Prevention (CEBP)-CEBP Focus]. In response, we highlight opportunities for cancer risk perception research when collecting and utilizing catchment-area data given the remarkably high proportions of individuals who report they are at average cancer risk, high levels of cancer risk information avoidance, and extremely negative ("death") associations with cancer. First, we advocate for enhanced measurement specificity regarding whether some participants may be uncertain regarding their cancer risk. Second, we advocate for examination of whether the large proportion of people who rate their risk as average have common (demographic and attitudinal) characteristics, which may dictate specific and targeted cancer prevention and control intervention. Finally, we advocate for further examination of cancer risk information avoidance and negative cancer associations to clarify subgroups that may fail to engage with risk information. Given the ubiquity of risk uncertainty, information avoidance, and negative cancer associations, further research into these prevalent beliefs will enhance our ability to bring the latest information regarding cancer prevention and control to the general population of the United States.

Low Health Literacy and Health Information Avoidance but Not Satisficing Help Explain "Don't Know" Responses to Questions Assessing Perceived Risk

BACKGROUND

People who say they don't know (DK) their disease risk are less likely to engage in protective behavior.

PURPOSE

This study examined possible mechanisms underlying not knowing one's risk for common diseases.

METHODS

Participants were a nationally representative sample of 1005 members of a standing probability-based survey panel who answered questions about their comparative and absolute perceived risk for diabetes and colon cancer, health literacy, risk factor knowledge and health information avoidance, and beliefs about illness unpredictability. Survey satisficing was a composite assessment of not following survey instructions, nondifferentiation of responses, haphazard responding, and speeding. The primary outcomes were whether a person selected DK when asked absolute and comparative risk perception questions about diabetes or colon cancer. Base structural equation modeling path models with pathways from information avoidance and health literacy/knowledge to DK responding for each DK outcome were compared to models that also included pathways from satisficing or unpredictability beliefs.

RESULTS

Base models contained significant indirect effects of health literacy (odds ratios [ORs] = 0.94 to 0.97, all P < 0.02) and avoidance (ORs = 1.05 to 1.15, all P < 0.01) on DK responding through risk factor knowledge and a direct effect of avoidance (ORs = 1.21 to 1.28, all P < 0.02). Adding the direct effect for satisficing to models resulted in poor fit (for all outcomes, residual mean square error estimates >0.17, all weighted root mean square residuals >3.2, all Comparative Fit Index <0.47, all Tucker-Lewis Index <0.49), indicating that satisficing was not associated with DK responding. Unpredictability was associated with not knowing one's diabetes risk (OR = 1.01, P < 0.01).

LIMITATIONS

The data were cross-sectional; therefore, directionality of the pathways cannot be assumed.

CONCLUSIONS

DK responders may need more health information, but it needs to be delivered differently. Interventions might include targeting messages for lower health literacy audiences and disrupting defensive avoidance of threatening health information.

Flood Risk Perceptions and Insurance Choice: Do Decisions in the Floodplain Reflect Overoptimism?

In the presence of rare disasters, risk perceptions may not always align with actual risks. These perceptions can nevertheless influence an individual's willingness to mitigate risks through activities such as purchasing flood insurance. In a survey of Maryland floodplain residents, we find that stated risk perceptions predict voluntary flood insurance take-up, while perceptions themselves varied widely among surveyed residents, owing in large part to differences in past flood experience. We use a formal test for overoptimism in risk perceptions and find that, on aggregate, floodplain residents are overly optimistic about flood risks.

Reaping the Benefits and Avoiding the Risks: Unrealistic Optimism in the Health Domain

People's perceptions of benefits and risks play a key role in their acceptance or rejection of medical interventions, yet these perceptions may be poorly calibrated. This online study with N = 373 adults aged 19-76 years focused on unrealistic optimism in the health domain. Participants indicated how likely they were to experience benefits and risks associated with medical conditions and completed objective and subjective numeracy scales. Participants exhibited optimistic views about the likelihood of experiencing the benefits and the side effects of treatment options described in the scenarios. Objective and subjective numeracy were not associated with more accurate ratings. Moreover, participants' underestimation of the risks was significantly greater than their overestimation of the benefits. From an applied perspective, these results suggest that clinicians may need to ensure that patients do not underestimate risks of medical interventions, and that they convey realistic expectations about the benefits that can be obtained with certain procedures.

Does a more complex service offering increase uncertainty in operations?

Purpose

The purpose of this paper is to investigate how the complexity of the service offering (service complexity) affects the uncertainty during service operations in engineering services. Specifically, the authors compare the existence of organisational, relational, environmental and technological uncertainty in maintenance services and performance-based services.

Design/methodology/approach

The authors present insights from four cases – two each for maintenance services and performance-based services. The in-depth data were based on 56 semi-structured interviews, multiple site visits, meeting notes, service contracts and other secondary data.

Findings

The case findings indicate that organisational and relational uncertainty were not linked to service complexity, while observations of environmental and technological uncertainty were higher and more varied for performance-based services. Based on these findings, the authors formulate four propositions regarding the relationship between service complexity and uncertainty in service operations.

Originality/value

This research contributes to the OM literature by suggesting that external sources of uncertainty increase with increasing service complexity, while internal sources of uncertainty remain unchanged.

Boosting intelligence analysts’ judgment accuracy: What works, what fails?

A routine part of intelligence analysis is judging the probability of alternative hypotheses given available evidence. Intelligence organizations advise analysts to use intelligence-tradecraft methods such as Analysis of Competing Hypotheses (ACH) to improve judgment, but such methods have not been rigorously tested. We compared the evidence evaluation and judgment accuracy of a group of intelligence analysts who were recently trained in ACH and then used it on a probability judgment task to another group of analysts from the same cohort that were neither trained in ACH nor asked to use any specific method. Although the ACH group assessed information usefulness better than the control group, the control group was a little more accurate (and coherent) than the ACH group. Both groups, however, exhibited suboptimal judgment and were susceptible to unpacking effects. Although ACH failed to improve accuracy, we found that recalibration and aggregation methods substantially improved accuracy. Specifically, mean absolute error (MAE) in analysts’ probability judgments decreased by 61% after first coherentizing their judgments (a process that ensures judgments respect the unitarity axiom) and then aggregating their judgments. The findings cast doubt on the efficacy of ACH, and show the promise of statistical methods for boosting judgment quality in intelligence and other organizations that routinely produce expert judgments.

Measuring Subjective Probabilities: The Effect of Response Mode on the Use of Focal Responses, Validity, and Respondents' Evaluations

Subjective probabilities are central to risk assessment, decision making, and risk communication efforts. Surveys measuring probability judgments have traditionally used open-ended response modes, asking participants to generate a response between 0% and 100%. A typical finding is the seemingly excessive use of 50%, perhaps as an expression of "I don't know." In an online survey with a nationally representative sample of the Dutch population, we examined the effect of response modes on the use of 50% and other focal responses, predictive validity, and respondents' survey evaluations. Respondents assessed the probability of dying, getting the flu, and experiencing other health-related events. They were randomly assigned to a traditional open-ended response mode, a visual linear scale ranging from 0% to 100%, or a version of that visual linear scale on which a magnifier emerged after clicking on it. We found that, compared to the open-ended response mode, the visual linear and magnifier scale each reduced the use of 50%, 0%, and 100% responses, especially among respondents with low numeracy. Responses given with each response mode were valid, in terms of significant correlations with health behavior and outcomes. Where differences emerged, the visual scales seemed to have slightly better validity than the open-ended response mode. Both high-numerate and low-numerate respondents' evaluations of the surveys were highest for the visual linear scale. Our results have implications for subjective probability elicitation and survey design.

In Defense of "Denial": Difficulty Knowing When Beliefs Are Unrealistic and Whether Unrealistic Beliefs Are Bad

Bioethicists often draw sharp distinctions between hope and states like denial, self-deception, and unrealistic optimism. But what, exactly, is the difference between hope and its more suspect cousins? One common way of drawing the distinction focuses on accuracy of belief about the desired outcome: Hope, though perhaps sometimes misplaced, does not involve inaccuracy in the way that these other states do. Because inaccurate beliefs are thought to compromise informed decision making, bioethicists have considered these states to be ones where intervention is needed either to correct the person's mental state or to persuade the person to behave differently, or even to deny the person certain options (e.g., another round of chemotherapy). In this article, we argue that it is difficult to determine whether a patient is really in denial, self-deceived, or unrealistically optimistic. Moreover, even when we are confident that beliefs are unrealistic, they are not always as harmful as critics contend. As a result, we need to be more permissive in our approach to patients who we believe are unrealistically optimistic, in denial, or self-deceived-that is, unless patients significantly misunderstand their situation and thus make decisions that are clearly bad for them (especially in light of their own values and goals), we should not intervene by trying to change their mental states or persuade them to behave differently, or by paternalistically denying them certain options (e.g., a risky procedure).

Reducing "I Don't Know" Responses and Missing Survey Data: Implications for Measurement

BACKGROUND

"I don't know" (DK) responses are common in health behavior research. Yet analytic approaches to managing DK responses may undermine survey validity and researchers' ability to interpret findings.

OBJECTIVE

Compare the usefulness of a methodological strategy for reducing DK responses to 3 analytic approaches: 1) excluding DKs as missing data, 2) recoding them to the neutral point of the response scale, and 3) recoding DKs with the mean.

METHODS

We used a 4-group design to compare a methodological strategy, which encourages use of the response scale after an initial DK response, to 3 methods of analytically treating DK responses. We examined 1) whether this methodological strategy reduced the frequency of DK responses, and 2) how the methodological strategy compared to common analytic treatments in terms of factor structure and strength of correlations between measures of constructs.

RESULTS

The prompt reduced DK response frequency (55.7% of 164 unprompted participants vs. 19.6% of 102 prompted participants). Factorial invariance analyses suggested equivalence in factor loadings for all constructs throughout the groups. Compared to excluding DKs, recoding strategies and use of the prompt improved the strength of correlations between constructs, with the prompt resulting in the strongest correlations (.589 for benefits and intentions, .446 for perceived susceptibility and intentions, and .329 for benefits and perceived susceptibility).

LIMITATIONS

This study was not designed a priori to test methods for addressing DK responses. Our analysis was limited to an interviewer-administered survey, and interviewers did not probe about reasons for DK responses.

CONCLUSION

Findings suggest that use of a prompt to reduce DK responses is preferable to analytic approaches to treating DK responses. Use of such prompts may improve the validity of health behavior survey research.

Public Understanding of Ebola Risks: Mastering an Unfamiliar Threat

Ebola was the most widely followed news story in the United States in October 2014. Here, we ask what members of the U.S. public learned about the disease, given the often chaotic media environment. Early in 2015, we surveyed a representative sample of 3,447 U.S. residents about their Ebola-related beliefs, attitudes, and behaviors. Where possible, we elicited judgments in terms sufficiently precise to allow comparing them to scientific estimates (e.g., the death toll to date and the probability of dying once ill). Respondents' judgments were generally consistent with one another, with scientific knowledge, and with their self-reported behavioral responses and policy preferences. Thus, by the time the threat appeared to have subsided in the United States, members of the public, as a whole, had seemingly mastered its basic contours. Moreover, they could express their beliefs in quantitative terms. Judgments of personal risk were weakly and inconsistently related to reported gender, age, education, income, or political ideology. Better educated and wealthier respondents saw population risks as lower; females saw them as higher. More politically conservative respondents saw Ebola as more transmissible and expressed less support for public health policies. In general, respondents supported providing "honest, accurate information, even if that information worried people." These results suggest the value of proactive communications designed to inform the lay public's decisions, thoughts, and emotions, and informed by concurrent surveys of their responses and needs.

What Factors Influence Women's Perceptions of their Systemic Recurrence Risk after Breast Cancer Treatment?

BACKGROUND

Breast cancer patients' misunderstanding of their systemic cancer recurrence risk has consequences on decision-making and quality of life. Little is known about how women derive their risk estimates.

METHODS

Using Los Angeles and Georgia's SEER registries (2014-2015), a random sample of early-stage breast cancer patients was sent surveys about 2 to 3 months after surgery ( N = 3930; RR, 68%). We conducted an inductive thematic analysis of open-ended responses about why women chose their risk estimates in a uniquely large sub-sample ( N = 1,754). Clinician estimates of systemic recurrence risk were provided for patient sub-groups with DCIS and with low-, intermediate-, and high-risk invasive disease. Women's perceived risk of systemic recurrence (0% to 100%) was categorized as overestimation, reasonably accurate estimation, or underestimation (0% for invasive disease) and was compared across identified factors and by clinical presentation.

RESULTS

Women identified 9 main factors related to their clinical experience (e.g., diagnosis and testing; treatment) and non-clinical beliefs (e.g., uncertainty; spirituality). Women who mentioned at least one clinical experience factor were significantly less likely to overestimate their risk (12% v. 43%, P < 0.001). Most women who were influenced by "communication with a clinician" had reasonably accurate recurrence estimates (68%). "Uncertainty" and "family and personal history" were associated with overestimation, particularly for women with DCIS (75%; 84%). "Spirituality, religion, and faith" was associated with an underestimation of risk (63% v. 20%, P < 0.001).

LIMITATIONS

The quantification of our qualitative results is subject to any biases that may have occurred during the coding process despite rigorous methodology.

CONCLUSIONS

Patient-clinician communication is important for breast cancer patients' understanding of their numeric risk of systemic recurrence. Clinician discussions about recurrence risk should address uncertainty and relevance of family and personal history.

Can you put too much on your plate? Uncertainty exposure in servitized triads

Purpose

Servitization increases the uncertainty exposure of provider firms due to the operational differences between services and production which is further increased when operations are set in triads. The purpose of this paper is to analyse the uncertainty exposure in servitized triads and explore suitable organisational responses.

Design/methodology/approach

A conceptual frame is defined detailing three uncertainty types (environmental, organisational and relational uncertainty) and suitable organisational responses to these. This frame guided the analysis of in-depth case evidence from a cross-national servitized triad in a European-North African set-up which was collected through 29 semi-structured interviews and secondary data.

Findings

The empirical study identified the existence of the three uncertainty types and directional knock-on effects between them. Specifically, environmental uncertainty created organisational uncertainty which in turn created relational uncertainty. The uncertainty types were reduced through targeted organisational responses where formal relational governance reduced environmental uncertainty, service capabilities reduced organisational uncertainty and informal relational governance reduced relational uncertainty. The knock-on effects were reduced through organisational and relational responses.

Originality/value

This paper makes two contributions. First, a structured analysis of the uncertainty exposure in servitized triads is presented which shows the existence of three individual uncertainty types and the knock-on effects between them. Second, organisational responses to reduce the three uncertainty types individually and the knock-on effects between them are presented.

Do Survey Probabilities Match Financial Market Beliefs?

This paper considers whether survey respondents' views regarding the likelihood of stock index returns exceeding specific thresholds are comparable to market views indicated by index options with strikes at analogous thresholds. It is motivated by the observation thatthe wording used to elicit subjective beliefs in surveys about expected future returns resembles the question a purchaser of a call option might ask. Building on this association, we document a similarity between the views of survey respondents and those of financial market participants as measured through call options, although the association is not one-for-one. We find a closer association for those demonstrating a better understanding of the laws of probability, suggesting that numeracy affects the accuracy of an elicited response.

Informing Reimbursement Decisions Using Cost-Effectiveness Modelling: A Guide to the Process of Generating Elicited Priors to Capture Model Uncertainties

In informing decisions, utilising health technology assessment (HTA), expert elicitation can provide valuable information, particularly where there is a less-developed evidence-base at the point of market access. In these circumstances, formal methods to elicit expert judgements are preferred to improve the accountability and transparency of the decision-making process, help reduce bias and the use of heuristics, and also provide a structure that allows uncertainty to be expressed. Expert elicitation is the process of transforming the subjective and implicit knowledge of experts into their quantifiable expressions. The use of expert elicitation in HTA is gaining momentum, and there is particular interest in its application to diagnostics, medical devices and complex interventions such as in public health or social care. Compared with the gathering of experimental evidence, elicitation constitutes a reasonably low-cost source of evidence. Given its inherent subject nature, the potential biases in elicited evidence cannot be ignored and, due to its infancy in HTA, there is little guidance to the analyst wishing to conduct a formal elicitation exercise. This article attempts to summarise the stages of designing and conducting an expert elicitation, drawing on key literature and examples, most of which are not in HTA. In addition, we critique their applicability to HTA, given its distinguishing features. There are a number of issues that the analyst should be mindful of, in particular the need to appropriately characterise the uncertainty associated with model inputs and the fact that there are often numerous parameters required, not all of which can be defined using the same quantities. This increases the need for the elicitation task to be as straightforward as possible for the expert to complete.

Relationship between Future Time Orientation and Item Nonresponse on Subjective Probability Questions: A Cross-Cultural Analysis

Time orientation is an unconscious yet fundamental cognitive process that provides a framework for organizing personal experiences in temporal categories of past, present and future, reflecting the relative emphasis given to these categories. Culture lies central to individuals' time orientation, leading to cultural variations in time orientation. For example, people from future-oriented cultures tend to emphasize the future and store information relevant for the future more than those from present- or past-oriented cultures. For survey questions that ask respondents to report expected probabilities of future events, this may translate into culture-specific question difficulties, manifested through systematically varying "I don't know" item nonresponse rates. This study drew on the time orientation theory and examined culture-specific nonresponse patterns on subjective probability questions using methodologically comparable population-based surveys from multiple countries. The results supported our hypothesis. Item nonresponse rates on these questions varied significantly in the way that future-orientation at the group as well as individual level was associated with lower nonresponse rates. This pattern did not apply to non-probability questions. Our study also suggested potential nonresponse bias. Examining culture-specific constructs, such as time orientation, as a framework for measurement mechanisms may contribute to improving cross-cultural research.

Relational uncertainty in service dyads

Purpose

Relational uncertainty determines how relationships develop because it enables the building of trust and commitment. However, relational uncertainty has not been explored in an inter-organisational setting. The purpose of this paper is to investigate how organisations experience relational uncertainty in service dyads and how they resolve it through suitable organisational responses to increase the level of service quality.

Design/methodology/approach

The author applies the overall logic of organisational information-processing theory and presents empirical insights from two industrial case studies collected via semi-structured interviews and secondary data.

Findings

The findings suggest that relational uncertainty is caused by the partner’s unresolved organisational uncertainty, i.e. their lacking capabilities to deliver or receive (parts of) the service. Furthermore, the author found that resolving the relational uncertainty increased the functional quality while resolving the partner’s organisational uncertainty increased the technical quality of the delivered service.

Originality/value

The author makes two contributions: first,the author introduces relational uncertainty to the OM literature as the inability to predict and explain the actions of a partnering organisation due to a lack of knowledge about their abilities and intentions; and second, the author presents suitable organisational responses to relational uncertainty and their effect on service quality.

A short note on measuring subjective life expectancy: survival probabilities versus point estimates

Understanding subjective longevity expectations is important, but measurement is not straightforward. Two common elicitation formats are the direct measurement of a subjective point estimate of life expectancy and the assessment of survival probabilities to a range of target ages. This study presents one of the few direct comparisons of these two methods. Results from a representative sample of the Dutch population indicate that respondents on average gave higher estimates of longevity using survival probabilities (83.6 years) compared to point estimates (80.2 years). Individual differences between elicitation methods were smaller for younger respondents and for respondents with a higher socioeconomic status. The correlation between the subjective longevity estimations was moderate, but their associations with respondents' characteristics were similar. Our results are in line with existing literature and suggest that findings from both elicitation methods may not be directly comparable, especially in certain subgroups of the population. Implications of inconsistent and focal point answers, rounding and anchoring require further attention. More research on the measurement of subjective expectations is required.

Differing types of medical prevention appeal to different individuals

We analyze participation in medical prevention with an expected utility model that is sufficiently rich to capture diverging features of different prevention procedures. The predictions of the model are not rejected with data from SHARE. A decrease in individual health decreases participation in breast cancer screening and dental prevention and increases participation in influenza vaccination, cholesterol screening, blood pressure screening, and blood sugar screening. Positive income effects are most pronounced for dental prevention. Increased mortality risk is an important predictor in the model for breast cancer screening, but not for the other procedures. Targeted screening and vaccination programs increase participation.

"I don't know" my cancer risk: exploring deficits in cancer knowledge and information-seeking skills to explain an often-overlooked participant response

BACKGROUND

Perceived risk is a central theoretical construct in health behavior research. Participants' "don't know" responses to perceived-risk items (DKPR) are usually excluded from analyses. Yet those who provide such responses may have unique cancer information needs.

OBJECTIVE

The hypotheses that DKPR responding may be due to cancer knowledge deficits or behavioral, skill, and attitudinal antecedents to knowledge deficits (information seeking, numeracy, and self-efficacy, respectively) were explored.

METHODS

Data from the 2005 Health Information National Trends Survey (HINTS; N = 1789), a US population-based survey, and an urban, minority, primary care clinic survey (N = 590) were analyzed. Multivariable logistic regressions were conducted to examine knowledge deficit explanations for responding DKPR to colon cancer risk perception questions (adjusting for demographics and family colorectal cancer history).

MEASURES

Comparative (HINTS) and absolute verbal perceived risk of colon cancer (HINTS, clinic survey), knowledge of colon cancer risks and screening, cancer/health information-seeking behavior and self-efficacy (HINTS), and numeracy (clinic survey).

RESULTS

Greater knowledge of colon cancer prevention and screening, cancer and health information seeking, and numeracy were each associated with lower odds of providing a DKPR response.

LIMITATIONS

The study was cross-sectional, which limits the ability to infer causal direction. The use of existing data sets limited our variable choices. Other plausible hypotheses may also explain DKPR responding.

CONCLUSIONS

People who report that they don't know their colon cancer risk may have low cancer knowledge and reduced knowledge acquisition behaviors and skills. Health behavior research could benefit from including data concerning DKPR responses to risk perception questions, because individuals who respond in this way may require interventions to address potential cancer risk knowledge deficits.

Rational expectations? An explorative study of subjective survival probabilities and lifestyle across Europe

BACKGROUND

Subjective survival probabilities (SSPs) are considered relevant in relation to lifestyle as lifestyle improvements may improve health and lower mortality risk.

OBJECTIVE

To study individuals' SSP in a population of elderly (i.e. 60 years and older) from 15 European countries.

METHODS

Data from the second wave of the Survey of Health, Ageing and Retirement in Europe (SHARE) were used. Individuals were asked about their chances to live up to age [T] or more. These SSPs were related to general characteristics, health and lifestyle. In addition, cross-country comparisons were made. The validity of the probabilistic elicitation format used for collecting SSPs was also addressed.

RESULTS

The average subjective probability of surviving the next 9-15 years was around 57%. Mean SSPs varied significantly across age, with lower means at higher ages. Cross-country comparisons showed lowest mean in the Czech Republic (42%) and the highest in Denmark (64%). SSPs correlated with socio-demographic, socio-economic and also strongly with (objective) health characteristics except for obesity. Smokers reported significantly lower SSPs compared to non-smokers, but no difference was found between non-smokers and quitters. Excessive alcohol consumers reported significantly higher SSPs than moderate consumers and abstainers, but this only held for female excessive drinkers. Physical inactivity was negatively associated with SSPs, but this relation was attenuated at higher ages. In this context, important cross-country differences were found.

CONCLUSIONS

Subjective survival probabilities are informative and relevant in relation to lifestyle decisions and can be validly obtained in elder people. The results from this study provide interesting implications for health policy, health communication strategies and future research.

Norm perception and communication for vasovagal symptoms in blood donation

BACKGROUND

Blood is a valuable resource, but most people do not donate. One deterrent to blood donation is the anticipation of vasovagal symptoms (e.g., dizziness, nausea, and fainting), despite the fact that such symptoms typically affect a small proportion of donors. The current research examined norm perceptions regarding vasovagal symptom experiences and used a message-framing paradigm to communicate accurate norm information and increase future donation intentions.

STUDY DESIGN AND METHODS

Three studies were conducted using young adult samples. In Study 1, donors and nondonors estimated the percentage of people who experience vasovagal symptoms. In Studies 2 and 3, nondonors and donors (respectively) were provided with accurate, positively framed, or negatively framed norm messages and indicated their intentions to donate.

RESULTS

In Study 1 we found that participants vastly overestimated how normative it was to experience vasovagal symptoms and this overestimation was stronger among nondonors. In Studies 2 and 3, we showed that positively framed normative messages ("90% of donors do not experience vasovagal symptoms") were generally more influential than negatively framed messages ("10% of donors do experience vasovagal symptoms"), except among past donors who had unfavorable donation experiences.

CONCLUSION

These findings suggest that targeting and correcting norm perception may be a critical step toward improving blood donation rates.

"Don't know" responses to risk perception measures: implications for underserved populations

BACKGROUND

Risk perceptions are legitimate targets for behavioral interventions because they can motivate medical decisions and health behaviors. However, some survey respondents may not know (or may not indicate) their risk perceptions. The scope of "don't know" (DK) responding is unknown.

OBJECTIVE

Examine the prevalence and correlates of responding DK to items assessing perceived risk of colorectal cancer.

METHODS

Two nationally representative, population-based, cross-sectional surveys (2005 National Health Interview Survey [NHIS]; 2005 Health Information National Trends Survey [HINTS]), and one primary care clinic-based survey comprised of individuals from low-income communities. Analyses included 31,202 (NHIS), 1,937 (HINTS), and 769 (clinic) individuals.

MEASURES

Five items assessed perceived risk of colorectal cancer. Four of the items differed in format and/or response scale: comparative risk (NHIS, HINTS); absolute risk (HINTS, clinic), and "likelihood" and "chance" response scales (clinic). Only the clinic-based survey included an explicit DK response option.

RESULTS

"Don't know" responding was 6.9% (NHIS), 7.5% (HINTS-comparative), and 8.7% (HINTS-absolute). "Don't know" responding was 49.1% and 69.3% for the "chance" and "likely" response options (clinic). Correlates of DK responding were characteristics generally associated with disparities (e.g., low education), but the pattern of results varied among samples, question formats, and response scales.

LIMITATIONS

The surveys were developed independently and employed different methodologies and items. Consequently, the results were not directly comparable. There may be multiple explanations for differences in the magnitude and characteristics of DK responding.

CONCLUSIONS

"Don't know" responding is more prevalent in populations affected by health disparities. Either not assessing or not analyzing DK responses could further disenfranchise these populations and negatively affect the validity of research and the efficacy of interventions seeking to eliminate health disparities.

Measuring risk perceptions: what does the excessive use of 50% mean?

OBJECTIVES

Risk perceptions are central to good health decisions. People can judge valid probabilities but use 50% disproportionately. The authors hypothesized that 50% is more likely than other responses to reflect not knowing the probability, especially among individuals with low education and numeracy, and evaluated the usefulness of eliciting "don't know" explanations.

METHODS

Respondents (n = 1020) judged probabilities for living or dying in the next 10 years, indicating whether they gave a good estimate or did not know the chances. They completed demographics, medical history, and numeracy questions.

RESULTS

Overall, 50% was more likely than other probabilities to be explained as "don't know" (v. "a good estimate"). Correlations of using 50% with low education and numeracy were mediated by expressing "don't know." Judged probabilities for survival and mortality explained as "don't know" had lower correlations with age, diseases, and specialist visits.

CONCLUSIONS

When judging risks, 50% may reflect not knowing the probability, especially among individuals with low numeracy and education. Probabilities expressed as "don't know" are less valid. Eliciting uncertainty could benefit theoretical models and educational efforts.

Assessing small non-zero perceptions of chance: The case of H1N1 (swine) flu risks

Feelings of unwarranted invulnerability, seen in judgments of 0% risk, can reflect misunderstandings of risk and risk behaviors, suggesting increased need for risk communication. However, judgments of 0% risk may be given by individuals who feel invulnerable, and by individuals who are rounding from small non-zero probabilities. We examined the effect of allowing participants to give more precise responses in the 0-1% range on the validity of reported probability judgments. Participants assessed probabilities for getting H1N1 influenza and dying from it conditional on infection, using a 0-100% visual linear scale. Those responding in the 0-1% range received a follow-up question with more options in that range. This two-step procedure reduced the use of 0% and increased the resolution of responses in the 0-1% range. Moreover, revised probability responses improved predictions of attitudes and self-reported behaviors. Hence, our two-step procedure allows for more precise and more valid measurement of perceived invulnerability.

Adolescents' perceived risk of dying

PURPOSE

Although adolescents' expectations are accurate or moderately optimistic for many significant life events, they greatly overestimate their chances of dying soon. We examine here whether adolescents' mortality judgments are correlated with their perceptions of direct threats to their survival. Such sensitivity would indicate the importance of ensuring that adolescents have accurate information about those threats, as well as the psychological support needed to deal with them.

METHODS

Data from two separate studies were used: a national sample of 3,436 14-18-year-old adolescents and a regional sample of 124 seventh graders and 132 ninth graders, 12-16 years old. Participants were asked about their chance of dying in the next year and before age 20, and about the extent of various threats to their physical well-being.

RESULTS

Adolescents in both samples greatly overestimated their chance of dying. Those mortality estimates were higher for adolescents who reported direct threats (e.g., an unsafe neighborhood). Thus, adolescents were sensitive to the relative size of threats to their survival, but not to the implications for absolute risk levels.

CONCLUSIONS

Contrary to the folk wisdom that adolescents have a unique sense of invulnerability, the individuals studied here reported an exaggerated sense of mortality, which was highest among those reporting greater threats in their lives. Such fears could affect adolescents' short-term well-being and future planning.

Avian influenza risk perception, Hong Kong

A telephone survey of 986 Hong Kong households determined exposure and risk perception of avian influenza from live chicken sales. Householders bought 38,370,000 live chickens; 11% touched them when buying, generating 4,220,000 exposures annually; 36% (95% confidence interval [CI] 33%-39%) perceived this as risky, 9% (7%-11%) estimated >50% likelihood of resultant sickness, whereas 46% (43%-49%) said friends worried about such sickness. Recent China travel (adjusted odds ratio 0.35; CI 0.13-0.91), traditional beliefs (1.20, 1.06-1.13), willingness to change (0.29, 0.11-0.81) and believing cooking protects against avian influenza (8.66, 1.61-46.68) predicted buying. Birth in China (2.79, 1.43-5.44) or overseas (4.23, 1.43-12.53) and unemployment (3.87, 1.24-12.07) predicted touching. Age, avian influenza contagion worries, husbandry threat, avian influenza threat, and avian influenza anxiety predicted perceived sickness risk. High population exposures to live chickens and low perceived risk are potentially important health threats in avian influenza.

Are Risk Assessments of a Terrorist Attack Coherent?

Four experiments examined 3 types of violations of coherence criteria in risk assessments of a terrorist attack. First, the requirement that extensionally equivalent descriptions be assigned the same probability (i.e., additivity) was violated. Unpacking descriptions of an attack into subtypes led to an increase in assessed risk. Second, additivity was also violated when risk assessments were obtained by subtracting the probability of no attack from 1.0. This refocusing procedure inflated assessed risk. Third, refocusing also increased the proportion of monotonicity violations in assessing risk across increasing or decreasing timeframes. Task structuring that promoted consideration of complementary possibilities increased coherence, suggesting that incoherence is due primarily to errors in applying rather than comprehending the relevant criteria.

Effects of fear and anger on perceived risks of terrorism: a national field experiment

The aftermath of September 11th highlights the need to understand how emotion affects citizens' responses to risk. It also provides an opportunity to test current theories of such effects. On the basis of appraisal-tendency theory, we predicted opposite effects for anger and fear on risk judgments and policy preferences. In a nationally representative sample of Americans (N = 973, ages 13-88) fear increased risk estimates and plans for precautionary measures; anger did the opposite. These patterns emerged with both experimentally induced emotions and naturally occurring ones. Males had less pessimistic risk estimates than did females, emotion differences explaining 60 to 80% of the gender difference. Emotions also predicted diverging public policy preferences. Discussion focuses on theoretical, methodological, and policy implications.