Judith Covey

On the Contingent Valuation of Safety and the Safety of Contingent Valuation: Part 1-Caveat Investigator

This article reports the results of two studies aimed at testing and refining a procedure for estimating willingness-to-pay based monetary values of safety using the contingent valuation method. In spite of the fact that respondents were given the opportunity to discuss various safety issues and key concepts in focus group meetings held in advance of individual interviews, and were also given ample opportunity to revise their responses in the light of the overall pattern of these responses, the results show clear evidence of extensive and persistent insensitivity to the scale and scope of the safety improvements that were specified in the contingent valuation questions, as well as vulnerability to framing effects. This clearly casts serious doubt on the reliability and validity of willingness-to-pay based monetary values of safety estimated using conventional contingent valuation procedures.

The effectiveness of one-to-one risk-communication interventions in health care: a systematic review

Objectives. To assess whether risk-communication interventions are associated with changes in patient knowledge, attitudes, and behaviors, and to identify aspects of these interventions that modify these effects. Design. Systematic review. Data sources. 96 studies from the period 1985-1996 retrieved by electronic searching of eight databases, hand searching of four journals, contacting key authors, and reference list searching. Main outcome measures. The effect size of the principal outcome was identified from each study. Outcomes measuring behavioral change were preferred; if these were not available, knowledge, anxiety, or risk perceptions were used, according to the focus of the study. Data were available to calculate the principal effect sizes for 82 of the studies. Analysis. Meta-regression. Results. The methodologic qualities of the studies varied. Nevertheless, risk-communication interventions generally had positive (beneficial) effects. Interventions addressing treatment choices were associated with larger effects than were those in other contexts, such as prevention or screening. Interventions using individual risk estimates were associated with larger effects than were those using more general risk information. Two design variables were identified as effect modifiers: randomized controlled trials were associated with smaller effects than other designs, and dichotomous outcomes were associated with larger effects than continuous outcomes. Conclusions. Risk communication interventions may be most productive if they include individual risk estimates in the discussion between professional and patient. Patient decisions about treatment appear more amenable to change by these interventions than attendance for screening or modification of risky behavior. Key words: risk communication; prevention interventions; patient behavioral changes; systematic review. (Med Decis Making 2000;20:290-297)

A Meta-analysis of the Effects of Presenting Treatment Benefits in Different Formats

Purpose. The purpose of this article is to examine the effects of presenting treatment benefits in different formats on the decisions of both patients and health professionals. Three formats were investigated: relative risk reductions, absolute risk reductions, and number needed to treat or screen. Methods. A systematic review of the published literature was conducted. Articles were retrieved by searching a variety of databases and screened for inclusion by 2 reviewers. Data were extracted on characteristics of the subjects and methodologies used. Log-odds ratios were calculated to estimate effect sizes. Results. A total of 24 articles were retrieved that reported on 31 unique experiments. The meta-analysis showed that treatments were evaluated more favorably when the relative risk format was used rather than the absolute risk or number needed to treat format. However, a significant amount of heterogeneity was found between studies, the sources of which were explored using subgroup analyses and metaregression. Although the subgroup analyses revealed smaller effect sizes in the studies conducted on physicians, the metaregression showed that these differences were largely accounted for by other features of the study design. Most notably, variations in effect sizes were explained by the particular wordings that the studies had chosen to use for the relative risk and absolute risk reductions. Conclusions. The published literature has consistently demonstrated that relative risk formats produce more favorable evaluations of treatments than absolute risk or number needed to treat formats. However, the effects are heterogeneous and seem to be moderated by key differences between the methodologies used.

The role of dispositional factors in moderating message framing effects.

OBJECTIVE Health messages can be framed in terms of the benefits of adopting a recommendation (gain frame) or the costs of not adopting a recommendation (loss frame). In recent years, research has demonstrated that the relative persuasiveness of gain and loss frames can depend on a variety of dispositional factors. This article synthesizes this growing literature to develop our understanding of the moderators of framing. METHOD A systematic review of published literature on gain and loss framing was conducted. Articles were retrieved that tested the interaction between framing and moderators representing individual differences in how people are predisposed to think, feel, and behave. The significance and direction of framing main effects and interactions were noted and effect size data extracted where available. RESULTS Forty-seven reports published between January 1990 and January 2012 were retrieved that reported on 50 unique experiments testing 23 different moderators. Significant interactions with typically small to medium simple main effect sizes were found in 37 of the 50 studies. Consistent interactions were found for factors such as ambivalence, approach-avoidance motivation, regulatory focus, need for cognition, and self-efficacy beliefs. Less consistent effects were found for perceived riskiness of activity, issue involvement, and perceived susceptibility/severity. CONCLUSION The relative effectiveness of gain- or loss-framed messages can depend on the disposition of the message recipient. Tailoring the frame to the individual therefore has the potential to maximize message persuasiveness.

Theory of Planned Behavior Interventions for Reducing Heterosexual Risk Behaviors: A Meta-Analysis

OBJECTIVE The meta-analysis reported here examined interventions informed by the theory of planned behavior (TPB) or theory of reasoned action (TRA) aimed at reducing heterosexual risk behaviors (prevention of STDs and unwanted pregnancy). METHODS Studies were eligible for inclusion if they were either randomized control trials or quasi-experimental studies that compared the TPB-based intervention against a control group. Search strategy consisted of articles identified in previous reviews, keyword search through search engines, examination of key journals, and contacting key experts. RESULTS Forty-seven intervention studies were included in the meta-analysis. Random effects models revealed that pooled effect sizes for TPB-based interventions had small but significant effects on behavior and other secondary outcomes (i.e., knowledge, attitudes, normative beliefs, perceived behavioral control, and intentions). Significant heterogeneity found between effect sizes was explored using metaregression. Larger effects were found for interventions that provided opportunities for social comparison. CONCLUSIONS The TPB provides a valuable framework for designing interventions to change heterosexual risk behaviors. However, effect sizes varied quite substantially between studies, and further research is needed to explore the reasons why.

Valuing Risk Reductions: Testing for Range Biases in Payment Card and Random Card Sorting Methods

Abstract Ongoing concerns with regard to the appropriate approach to elicitation of willingness-to-pay responses in contingent valuation studies have led to the development of a number of alternative techniques. One of the most recent, and on the surface, most promising of these is the random card sorting approach (RCS) which has been used for policy purposes to value risk reductions. This paper provides the first formal test of this procedure, comparing it against the widely used payment card (PC) format from which it is developed and whose recognised problems, such as range bias, it claims to address. However, the findings suggest that the RCS procedure is no less vulnerable to range bias than the PC method for eliciting both monetary values of health risk reductions and non-monetary estimates of death rates. Conclusions for future research initiatives are drawn.

Subarachnoid Hemorrhage Patients' Fears of Recurrence Are Related to the Presence of Posttraumatic Stress Disorder

BACKGROUND:Subarachnoid hemorrhage (SAH) patients illustrate a chronic fear of recurrence. A third of patients develop posttraumatic stress disorder (PTSD) after SAH, and PTSD after other conditions is associated with a more negative outlook on life. OBJECTIVE:We examined whether recurrence fears are related to PTSD and whether this is associated with the patients making more negative health appraisals. We also examined the helpfulness of current treatments. METHODS:Two SAH samples were generated. Sample 1 (n = 82) was assessed 13 months after ictus for PTSD, cognition, fear of recurrence, and beliefs concerning future health. Sample 2 (n = 60) was assessed 18 months after ictus for PTSD and to determine how much current treatments increased their confidence about not having another SAH. RESULTS:Thirty-four percent of sample 1 had PTSD. Although clinically and cognitively comparable, PTSD patients feared recurrence more and were comparatively more pessimistic about their chances of further SAH. Thirty-six percent of sample 2 had PTSD. These most fearful patients reported finding current treatments the least helpful. CONCLUSION:Fear of recurrence after SAH is related to PTSD. Participants with PTSD were more pessimistic about their future health. Treatment for PTSD could alleviate fears of SAH recurrence and promote better outcome.

The Effects of Absolute Risks, Relative Risks, Frequencies, and Probabilities on Decision Quality

It is important to understand how the quality of peoples decision making may be affected by the format used to present treatment benefits. Two experiments compared the accuracy of presenting the benefits of cancer screening tests or vaccines using either absolute or relative risk formats that included baseline risk information. Moreover, the absolute and/or baseline risks were presented using either natural frequencies or probabilities. In both experiments, accuracy was measured by the sensitivity of choices to differences in absolute rather than relative risks. Experiment 1 showed no significant differences in sensitivity between the relative and absolute risk formats when the risks were presented as natural frequencies. Sensitivity was, however, poor in both probability versions. Experiment 2 tested the natural frequency versions more stringently by presenting choices with different levels of difficulty. The author found that decision quality was significantly less affected by increases in difficulty in the absolute risk format. Presenting baseline risks using natural frequencies may help to reduce the biasing effects of relative risks but decision quality may not be on a par with the accuracy of decisions made when absolute risks are presented in natural frequency formats.

Past and Future Implications of Near-Misses and Their Emotional Consequences

The Reflection and Evaluation Model (REM) of comparative thinking predicts that temporal perspective could moderate peoples emotional reactions to close counterfactuals following near-misses (Markman & McMullen, 2003). The experiments reported in this paper tested predictions derived from this theory by examining how peoples emotional reactions to a near-miss at goal during a football match (Experiment 1) or a close score in a TV game show (Experiment 2) depended on the level of perceived future possibility. In support of the theory it was found that the presence of future possibility enhanced affective assimilation (e.g., if the near-miss occurred at the beginning of the game the players who had nearly scored were hopeful of future success) whereas the absence of future possibility enhanced affective contrast (e.g., if the near-miss occurred at the end of the game the players who had nearly scored were disappointed about missing an opportunity). Furthermore the experiments built upon our theoretical understanding by exploring the mechanisms which produce assimilation and contrast effects. In Experiment 1 we examined the incidence of present-oriented or future-oriented thinking, and in Experiment 2 we examined the mediating role of counterfactual thinking in the observed effect of proximity on emotions by testing whether stronger counterfactuals (measured using counterfactual probability estimates) produce bigger contrast and assimilation effects. While the results of these investigations generally support the REM, they also highlight the necessity to consider other psychological mechanisms (e.g., social comparison), in addition to counterfactual thinking, that might contribute to the emotional consequences of near-miss outcomes.

People's Preferences for Safety Control: Why Does Baseline Risk Matter?

Previous tests of how peoples valuations of safety vary with the level of baseline risk have left policymakers with a rather mixed message. Some data support the conventional hypothesis derived from economic theory that marginal valuations of risk changes increase with the baseline level, but other data reject it. With these indeterminate findings in mind, the present study adopted an in-depth quantitative-qualitative methodology to explore the preferences of a general population sample (N = 147) for safety programs targeted at hazards with different age groups at risk and numbers of deaths per year. The data clearly showed that self- or household interest mattered to people (e.g., programs in which the respondent or their household members were in the at-risk age group were evaluated more positively). The number of deaths also mattered, although not always for reasons strictly consistent with the conventional hypothesis. Rather, the qualitative findings suggested that evaluations may be driven by auxiliary assumptions about aspects of the programs induced by this information (e.g., people believe that a higher number of deaths is an indicator that more people are likely to be exposed to that hazard). These findings bring into question the extent to which quantitative responses from stated preference surveys can be taken at face value to form a reliable basis for public policy.