How Much Will the Sea Level Rise? Outcome Selection and Subjective Probability in Climate Change Predictions

We tested whether people focus on extreme outcomes to predict climate change and assessed the gap between the frequency of the predicted outcome and its perceived probability while controlling for climate change beliefs. We also tested 2 cost-effective interventions to reduce the preference for extreme outcomes and the frequency–probability gap by manipulating the probabilistic format: numerical or dual-verbal-numerical. In 4 experiments, participants read a scenario featuring a distribution of sea level rises, selected a sea rise to complete a prediction (e.g., “It is ‘unlikely’ that the sea level will rise . . . inches”) and judged the likelihood of this sea rise occurring. Results showed that people have a preference for predicting extreme climate change outcomes in verbal predictions (59% in Experiments 1–4) and that this preference was not predicted by climate change beliefs. Results also showed an important gap between the predicted outcome frequency and participants’ perception of the probability that it would occur. The dual-format reduced the preference for extreme outcomes for low and medium probability predictions but not for high ones, and none of the formats consistently reduced the frequency–probability gap

A direct and comprehensive test of two postulates of politeness theory applied to uncertainty communication

Applied to uncertainty communication, politeness theory postulates that when announcing bad news (1) speakers may intend not only to inform, but also to manage (e.g., save) the hearers? or speakers? own faces (i.e., face-managing intentions), and (2) speakers may perform face-managing intentions by altering the explicitly communicated probability. Previous research has assumed these two core postulates when explaining various reasoning and judgment phenomena in hearers, but has failed to test them empirically in a comprehensive and direct way: jointly in relation to speakers. To provide this critical evidence, we asked subjects to communicate a predefined numerical probability of two negative outcomes, using a verbal probability scale. Subjects reported their communication intentions afterwards. In line with the first politeness theory postulate, speakers intended not only to be informative but also to tactfully announce bad news or to avoid being blamed in case they made inaccurate (too low or too high) prediction. In line with the second politeness theory postulate, speakers altered their explicitly communicated probability more often and more substantially when adopting f ace-managing intentions than when adopting informative intentions. We discuss how this evidence corroborates the politeness theory and validates the previous research that focused on hearers

Ratio format shapes health decisions: The practical significance of the "1-in-X" effect

Prior research found that “1-in-X” ratios led to higher and less accurate subjective probability than “N-in-X*N” ratios or other formats even though they featured the same mathematical information. It is unclear, however, whether the effect transfers into health decisions and the practical significance of the effect is undetermined. Based on previous findings and risk communication theories, we hypothesised that the “1-in-X” effect would occur and transfer into relevant decisions. We also tested whether age, gender and education differences would moderate the “1-in-X” effect on decision-making. We conducted three well-powered experiments (n = 1912) using a sample from the general adult UK population to test our hypotheses, estimated the effect and excluded a possible methodological explanation for such a transfer. In hypothetical scenarios, participants decided whether to travel to Kenya given the chance of contracting malaria (Experiment 1) and whether to take recommended steroids given the side effects (Experiments 2 and 3). Across the experiments, we replicated a small-to-medium “1-in-X” effect on the perceived probability, Hedge’s g = -0.36, 95% CI [-0.47, -0.24], z = -6.18, p < .001 and found a small effect on subsequent decisions, OR = 1.32, 95% CI [1.10, 1.59], z = 2.99, p = .003. The perceived probability fully mediated the effect of the ratio format on decision. Age, gender and education did not moderate the “1-in-X” effect on decision. We argue that a high prevalence of “1-in-X” ratios in medical communication makes these small changes clinically relevant. Therefore, to communicate information accurately, “1-in-X” ratios should not be used or at least used cautiously in medical communication

Should we stop referring to the pandemic of antimicrobial resistance as silent?

Background: Referring to the ongoing antimicrobial resistance crisis as a 'silent' pandemic has gained popularity, but there are mixed views on whether such a phrase should be used in public health communication. Some researchers have argued that using the term 'silent pandemic' may lower the perceived threat and hinder mobilization efforts to tackle the problem. Objectives: I investigated the impact of the phrase 'silent pandemic' on perceived threat levels and mobilization intentions. Methods: In three experiments (n=1677), participants from the UK's general adult population were randomly allocated to either a 'pandemic' or 'silent pandemic' condition, where the different terms were embedded in statements (Experiment 1) or brief information materials (Experiments 2 and 3). The term 'silent pandemic' was also presented with a brief description of its intended meaning (Experiment 3). The participants expressed their perception of the threat and their mobilization intentions. Results: In Experiments 1 and 2, referring to the pandemic as silent did not significantly affect the perceived threat (Cohen's d=-0.06; Cohen's d=0.08, respectively) or mobilization intentions (Cohen's d=-0.07; Cohen's d=0.11, respectively). However, in Experiment 3, the term 'silent pandemic' decreased the perceived threat and mobilization intentions (Cohen's d=0.27; Cohen's d=0.35, respectively). Conclusions: Describing the pandemic as 'silent' yielded no measurable effects on perceived threat and mobilization intentions but it showed depreciating effects when accompanied by its intended meaning. Taken together, it is advisable to avoid the term

Adaptive cooperation in the face of social exclusion

The extent to which socially excluded individuals are willing to collaborate with others is an important theoretical and practical question. We consider four contrasting predictions based on the existing psychological literature. The first two are derived from the need-threat literature: Following social rejection individuals may withdraw from cooperative interaction in general (aggression hypothesis), or cooperate more in general (reconnection hypothesis). Alternatively, performance of the excluded individuals in cooperative tasks may worsen reflecting reduced ability to deliberate (cognitive depletion hypothesis). Finally, excluded individuals may cooperate less with those who rejected them (revenge hypothesis). We tested these hypotheses in three incentivized experiments. In each, we first varied whether participants were excluded or included in a virtual ball-passing game. In the second part, participants entered a two-player investment game, in which their earnings were partly dependent on the cooperativeness of their partner. We varied how cooperative the co-player was, and measured whether our participants were willing to cooperate or not. All participants entered the game twice, once with an unknown player, and once with a person who they previously encountered during the ball-passing task. Our findings were consistent with the revenge hypothesis – excluded participants were less cooperative when they were paired with the individual who previously excluded them. Interactions with unknown players were unaffected – excluded and included participants were equally cooperative. We propose a straightforward explanation of our findings: People do not like to cooperate with those who previously rejected them, but the experience of rejection does not have broad implications for people's overall willingness to cooperate

1-in-X" bias: "1-in-X" format causes overestimation of health-related risks

According to the "1-in-X" effect, "1-in-X" ratios (e.g., 1 in 12) trigger a higher subjective probability than numerically equivalent "N-in-X*N" ratios (e.g., 3 in 36). Here we tested: (i) the effect on objective measures, (ii) its consequences for decision-making, (iii) whether this effect is a form of bias by measuring probability accuracy, and (iv) its amplification in people with lower health literacy and numeracy. In parallel-designed experiments, 975 participants from the general adult population participated in one of five experiments following a 2(format: "1-in-X" or "N-in-X*N") × 4(scenarios) mixed design. Participants assessed the risk of contracting a disease on either a verbal probability scale (Exp. 1), or a numerical probability/frequency scale with immediate (Exp. 2-3) or delayed presentation (Exp. 4-5). Participants also made a health-related decision and completed a health literacy and numeracy scale. The "1-in-X" ratios yielded higher probability perceptions than the "N-in-X*N" ratios and affected relevant decisions. Critically, the "1-in-X" ratios led to a larger objective overestimation of numerical probabilities than the "N-in-X*N" ratios. People with lower levels of health literacy and numeracy were not more sensitive to the bias. Health professionals should use "1-in-X" ratios with great caution when communicating to patients, because they overestimate health risks

"I am uncertain" vs "It is uncertain". How linguistic markers of the uncertainty source affect uncertainty communication

Two psychological sources of uncertainty bear implications for judgment and decision-making: external uncertainty is seen as stemming from properties of the world, whereas internal uncertainty is seen as stemming from lack of knowledge. The apparent source of uncertainty can be conveyed through linguistic markers, such as the pronoun of probability phrases (e.g., I am uncertain vs. It is uncertain). Here, we investigated whether and when speakers use different pronoun subjects as such linguistic markers (Exp. 1 and 2) and what hearers infer from them (Exp. 3 and 4). Speakers more often described higher probabilities and knowable outcomes with internal probability phrases. In dialogue, speakers mirrored the source of their conversational partner. Markers of the source had a main effect or interacted with the probability conveyed and speaker expertise to shape the judgments and decisions of hearers. For example, experts voicing an internal probability phrase were judged as more knowledgeable than experts using an external probability phrase whereas the result was the opposite for lay speakers. We discuss how these findings inform our understanding of subjective uncertainty and uncertainty communication theories

Determinants of satisfaction with information and additional information-seeking behaviour for the pertussis vaccination given during pregnancy

Objectives: Information search and processing is critical to the vaccine decision-making process. However, the role of drivers of information satisfaction and search is not fully understood. Here, we investigated the predictive potential of psychosocial characteristics related to satisfaction with information and additional information-seeking about the pertussis vaccine currently recommended during pregnancy. Design: Cross-sectional online questionnaire study. Methods: A UK based sample of 314 women who had given birth during the previous six months was recruited to participate. The questionnaire included measures of the psycho-social predictors: trust, coping strategies, attitude towards vaccine information-seeking behaviour and risk perception of vaccination during pregnancy, and measures of two outcome variables: satisfaction with information received from a health care professional and whether participants engaged in vaccine information-seeking behaviour. Results: Trust in health care professionals, a perceived behavioural control of own vaccine information-seeking behaviour, and an engaged problem-focused strategy for coping with stress were significant predictors of satisfaction with official information given by a health care professional. 40% of women sought out additional information about vaccination however, none of the psychosocial factors measured significantly predicted the behaviour. Conclusions: We found that high trust in health care professionals, a perceived ability to seek out accurate information about vaccines and actively focusing on problems as a means of coping with stress, drives satisfaction in official vaccine information. We also developed measures of these variables that could be used in further research

Expectations for antibiotics increase their prescribing: Causal evidence about localized impact.

Objective: Clinically irrelevant but psychologically important factors such as patients' expectations for antibiotics encourage overprescribing. We aimed to (a) provide missing causal evidence of this effect, (b) identify whether the expectations distort the perceived probability of a bacterial infection either in a preor postdecisional distortions pathway, and (c) detect possible moderators of this effect. Method: Family physicians expressed their willingness to prescribe antibiotics (Experiment 1, n1 = 305) or their decision to prescribe (Experiment 2, n2 = 131) and assessed the probability of a bacterial infection in hypothetical patients with infections either with low or high expectations for antibiotics. Response order of prescribing/ probability was manipulated in Experiment 1. Results: Overall, the expectations for antibiotics increased intention to prescribe (Experiment 1, F(1, 301) = 25.32, p < .001, ηp2 = .08, regardless of the response order; Experiment 2, odds ratio [OR] = 2.31, and OR = 0.75, Vignettes 1 and 2, respectively). Expectations for antibiotics did not change the perceived probability of a bacterial infection (Experiment 1, F(1, 301) = 1.86, p = .173, ηp2 = .01, regardless of the response order; Experiment 2, d=-0.03, and d = +0.25, Vignettes 1 and 2, respectively). Physicians' experience was positively associated with prescribing, but it did not moderate the expectations effect on prescribing. Conclusions: Patients' and their parents' expectations increase antibiotics prescribing, but their effect is localized-it does not leak into the perceived probability of a bacterial infection. Interventions reducing the overprescribing of antibiotics should target also psychological factors

Prevalence and alternative explanations influence cancer diagnosis: An experimental study with physicians.

Objective: Cancer causes death to millions of people worldwide. Early detection of cancer in primary care may enhance patients’ chances of survival. However, physicians often miss early cancers, which tend to present with undifferentiated symptoms. Within a theoretical framework of the hypothesis generation (HyGene) model, together with psychological literature, we studied how 2 factors—cancer prevalence and an alternative explanation for the patient’s symptoms—impede early cancer detection, as well as prompt patient management. Method: Three hundred family physicians diagnosed and managed 2 patient cases, where cancer was a possible diagnosis (one colorectal cancer, the other lung cancer). We employed a 2 (cancer prevalence: low vs. high) × 2 (alternative explanation: present vs. absent) between-subjects design. Cancer prevalence was manipulated by changing either patient age or sex; the alternative explanation for the symptoms was manipulated by adding or removing a relevant clinical history. Each patient consulted twice. Results: In a series of random-intercept logistic models, both higher prevalence (OR = 1.92, 95% confidence interval [CI 1.27, 2.92]) and absence of an alternative explanation (OR = 1.70, 95% CI [1.11, 2.59]) increased the likelihood of a cancer diagnosis, which, in turn, increased the likelihood of prompt referral (OR = 22.84, 95% CI [16.14, 32.32]). Conclusions: These findings confirm the probabilistic nature of the diagnosis generation process and validate the application of the HyGene model to early cancer detection. Increasing the salience of cancer—such as listing cancer as a diagnostic possibility—during the initial hypothesis generation phase may improve early cancer detection