Monday, October 24, 2011: 4:30 PM
Columbus Hall C-F (Hyatt Regency Chicago)
Category Reference
BECBehavioral Economics ESPApplied Health Economics, Services, and Policy Research
DEC Decision Psychology and Shared Decision Making METQuantitative Methods and Theoretical Developments

  * Candidate for the Lee B. Lusted Student Prize Competition

Session Chairs:
Alan Schwartz, PhD and Angela Fagerlin, PhD
4:30 PM
Alberto Longo, PhD, Jose Grisolia and W. George Hutchinson, Professor, Queen's University Belfast, Belfast, Northern Ireland

Purpose: To assess the Willingness To Pay (WTP) to reduce Coronary Heart Disease (CHD) risk and to assess the Value of a Statistical Life (VSL) for CHD risk reductions from changing dietary habits and amount of physical activity in the Northern Ireland.

Method: A stratified sample of 519 persons representative of the Northern Ireland population aged 40-65 were administered with a Choice Experiments (CE) questionnaire through computer assisted personal interviews, conducted in the house of the respondents, during January – March 2011. Respondents were queried about their medical history, eating habits, and levels of physical activity to present them with their own CHD risk in the next ten years. Respondents were then shown ten CE questions where they were asked to trade off their current lifestyle with hypothetical lifestyle options, described by reduction in unhealthy food items, increase in the consumption of fruit and vegetables, increase in the amount of physical activity, reduction in the risk of a heart attack, and increase in weekly expenditures. We use Mixed logit models to analyze the CE data.

Result: Respondents are on average willing to pay £0.03/minute per week for increasing their amount of Physical Activity, which is equal to £5.18 to reach the recommended amount of 30 minutes of Physical Activity 5 times/week.  Respondents need to be compensated, as they have a WTP equal to £-0.01/gram of fat per week, for reducing fat content from diet and replacing fatty items with fruit and vegetables. Respondents are also willing to pay £0.81 per week for reducing their own CHD risk by 1% over the next 10 years. When controlling for income, BMI, and health status, we find that respondents with higher BMI levels are willing to pay more for increasing their amount of physical activity, and need to receive higher compensations for reducing fat content from their diets. Considering a 3.5% discount rate, the VSL is equal to £610,944.

Conclusion: A policy to reduce obesity should invest more public money in programs that promote physical activity, rather than making unhealthy food less attractive. Our results show that people with high BMI levels are more likely to choose a lifestyle option characterized by increased levels of physical activity, rather than by a food basked that entails a sacrifice in terms of reduced fat content.

4:45 PM
Lorens A. Helmchen, Ph.D., George Mason University, Fairfax, VA and Avraham Stoler, Ph.D., De Paul University, Chicago, IL

Purpose: To examine why so few individuals at risk of Huntington disease (HD) seek genetic testing and why the propensity to test increases with the belief of carrying the gene.

Methods: HD is an inherited disorder generally characterized by the adult onset of impaired movement and cognitive decline that commonly leads to institutional care and eventually death within 20 years. A genetic test that can confirm or rule out with near-certainty whether an individual will develop HD is inexpensive and widely available. As the disease has no cure, the test does not help improve treatment but it can guide individuals in their decisions about education, marriage, fertility, savings, and retirement. Given the disease’s substantial mortality and morbidity impact, neo-classical models predict that individuals at risk of HD value genetic testing highly, yet fewer than 10% opt for the test. Moreover, the propensity to test has been observed to increase with individuals’ belief that they will develop HD, contradicting neo-classical predictions. Using survey data from 64 untested individuals at risk of HD (mean age: 44 years; 42% male; 84% white; mean years of education: 14.5), we test whether respondents' stated advantages and disadvantages of testing for HD reveal an asymmetry between the perceived loss in utility of confirming the eventual onset of HD and the perceived utility gain of ruling it out. We also test whether the stated advantages and disadvantages of testing vary with respondents’ experience of symptoms, which inform their beliefs about HD.

Results: 53% of respondents feared “depression after confirming HD”, while only 5% of respondents explicitly mentioned the possibility of “feeling much better” after ruling it out. Moreover, after controlling for respondent demographics, symptomatic respondents were substantially and significantly less likely than non-symptomatic respondents to fear depression after confirming HD (-36 percentage points, p=0.006), while respondents rarely considered the possibility of “feeling much better” as an advantage of testing regardless of symptom onset (-4 percentage points, p=0.439). We show that a simple modification of the neo-classical model in which individuals assign greater weight to losses relative to gains can account for these survey response patterns.

Conclusion: Survey responses of individuals at risk of HD are consistent with Prospect Theory, in which subjects systematically overweight the losses relative to the gains of genetic testing.

5:00 PM
X.T. Wang, Ph.D.1, Shu Li, Ph.D.2 and Lilin Rao2, (1)University of South Dakota, Vermillion, SD, (2)Chinese Academy of Sciences, Beijing, China

Purpose: In two studies, we examined metabolic mechanisms of intertemporal choice within a synthetic framework of life-history theory and risk sensitive foraging theory. In a previous study (Wang & Dvorak, 2010) we identified a novel link between blood glucose (GB) levels and delay (future) discounting. People discount the future when they prefer a smaller and sooner (SS) reward to a larger but later (LL) reward when making intertemporal choices. We found that a sugar drink reduced delay discounting, making the LL options more attractive whereas a diet drink increased delay discounting, making the SS options more preferable. Based on these findings, we predict that when the body energy budget is low, the delay discounting rate would increase to get immediate supply, and vice versa.

Method: In Study 1, we examined the effects of varying BG levels on delay discounting in natural conditions measured by subjective ratings of hunger and actual temporal distance from the last meal. In Study 2, we checked the BG levels of the participants before making a hypothetical investment decision of allocating a certain amount of tax return for immediate use vs. short-term or/and long-term saving. We also examined the issue of resource allocation. The participants were asked to answer questions about contents and intension of a conversion between a man and a woman portrayed in a photo.

Result: The results from Study 1showed that the temporal distance but not subjective hunger perception was significantly and positively correlated with delay discounting. Results from Study 2 showed that the participants with higher BG levels were more likely to save the money for future use. The participants who were low in the BG levels were more likely to interpret the conversation in terms of sexual nature.

Conclusion: Fluctuating blood glucose levels continuously inform the brain about body energy budget, and allow the brain to regulate intertemporal choice adaptively by adjusting delay discounting rate and by making trade-offs between survival-related calorie intake and reproduction-related mating processes.

5:15 PM
Scott D. Halpern, MD, PhD, MBE1, Kevin Volpp, MD, PhD1, George Lowenstein, PhD2, Elizabeth Cooney, MPH1, Tatiana Silva, MPA1, Robert M. Arnold, MD3, Derek C. Angus, MD, MPH, FRCP3 and Cindy L. Bryce, PhD3, (1)University of Pennsylvania School of Medicine, Philadelphia, PA, (2)Carnegie Mellon University, Pittsburgh, PA, (3)University of Pittsburgh School of Medicine, Pittsburgh, PA

Purpose: To examine how default options affect chronically ill patients’ goals of care and elections to receive specific interventions when completing real advance directives (ADs).

Methods: Randomized trial of patients with non-curable lung diseases recruited from pulmonary and oncology clinics.  Patients were assigned with equal probabilities to complete (1) an opt-out AD (modeled on the Allegheny County Medical Society’s advocated form) in which the default goal of care prioritized extending life “even if that means I may have more pain and suffering,” and patients could opt out individually from 5 interventions (e.g., mechanical ventilation); (2) an opt-in AD in which the default goal of care prioritized comfort “even if that means not living as long” and patients could opt into 5 interventions; or (3) a neutral AD in which patients not making active choices effectively were choosing not to specify a plan of care or intervention preference.  

Results: Among 130 patients enrolled, 38 (29%) completed an AD that was signed by their surrogates and incorporated into their medical records. Non-completion rates were similar across the 3 arms (all p > 0.5), and intention-to-treat analyses produced results similar to the per-protocol analyses reported here. Patients completing opt-in ADs (78%) were the most likely to select the comfort-oriented plan of care, followed by patients completing neutral ADs (57%) and opt-out ADs (20%) (p < 0.001 for trend). Patients completing opt-in rather than opt-out AD’s were more likely to choose to forgo ICU admission, dialysis, and feeding tube insertion (all p < 0.05); corresponding but non-significant findings were noted for mechanical ventilation (p = 0.074) and cardiopulmonary resuscitation (p = 0.088). Patients completing neutral ADs had probabilities of forgoing each service that were intermediate between those for patients completing opt-in and opt-out ADs.

Conclusions: Building on prior research in hypothetical settings, this study provides the first randomized evidence that default options influence real healthcare decisions. Future research is needed to identify methods for increasing AD completion and to quantify how altering the choices patients make in ADs influence their receipt of wanted and unwanted healthcare services, costs of care, and satisfaction with care.

5:30 PM
Liana Fraenkel, MD, MPH, Yale School of Medicine, New Haven, CT, Ellen Peters, Ph.D., Decision Research, Eugene, OR and Valerie Reyna, PhD, Cornell University, Ithaca, NY

Purpose: American College of Rheumatology guidelines “strongly recommend” aggressive care with disease modifying anti-rheumatic drugs (DMARDs) in order to achieve and maintain tight control in rheumatoid arthritis (RA). Despite the widespread endorsement of this approach, data suggest that many patients are not effectively treated. There are currently no proven mechanisms to effectively inform patients and enable them to process the complex information involving decisions related to escalating care. The objective of this study is to develop a decision tool to effectively inform and “nudge” RA patients with active disease to accept additional therapy.

Methods: We first performed a systematic review to generate the outcome data and risk estimates required for the tool. A Delphi panel of experts was used to determine which AEs should be represented to all subjects to ensure informed consent. Additional information can be accessed through links for those desiring additional information. Probabilistic information is presented using theoretically motivated manipulations; e.g.: bar graphs to emphasize relative benefits and pie charts to emphasize the denominator. Participants perform a Best-Worst scaling exercise after viewing the informational content to clarify their priorities. We conducted a pre-post test pilot study to assess the feasibility, acceptability, and preliminary evidence of the tool’s efficacy in improving informed choice.

Results: We interviewed104 subjects; mean age (SD) = 62 (12); 84% female, 86% White; median duration of RA =13 years (range 1-61). Knowledge (sum of correct responses to 20 questions) and willingness to take a biologic (11-point numeric rating scale) significantly improved after viewing the tool (mean differences 3.1 and 1.4 respectively, both p < 0.0001). Decisional conflict (informed and value subscales) also significantly decreased (mean differences 20.4 and 20.7, both p<0.001). Increased willingness to take a biologic was greater among younger adults and those with a college education. Improvement in knowledge was seen across ages and educational backgrounds. Over 90% of participants ratings; related to the quality and quantity of information were very good or excellent. 89% found the tool to be very helpful and all would recommend it for patients with RA.

Conclusion: A tool designed based on the principles of Fuzzy Trace theory to nudge patients towards accepting “strong recommendations” increased knowledge, decreased decisional conflict, and increased patient willingness to escalate care in a pre-post test setting.

5:45 PM
Richard W. Martin, MD, MA1, Patience J. Gallagher, B.S.2 and Donald J. Tellinghuisen, PhD2, (1)Michigan State University, Grand Rapids, MI, (2)Calvin College, Grand Rapids, MI

Purpose:   To explore the validity of generalizing the results from first year psychology students in message framing laboratory experiments to patient decision aid design.

Method:    91 first year psychology students and 91 rheumatoid arthritis (RA) patients participated in a prospective randomized, single blind, factorial experimental design evaluating the effect of four information formats on: satisfaction with risk communication and verbatim and gist recall of a hypothetical drug’s ability to slow the rate of progression of structural joint damage (SJD). The study was conducted in 2 different settings using similar experimental procedures. College students enrolled in an introductory psychology class were evaluated in a traditional experimental laboratory setting.  Patients were evaluated in a conference room adjacent to the clinic waiting room following a routinely scheduled clinic visit.

Result:   Demographics of students and patients were respectively:  Mean age 19.4 years (18-25) vs. 61.7 years (18-86), female gender 50.5 vs. 60.0%, minority ethnicity 1.1 vs. 5.4%.  Less than high school graduate 0 vs. 10.0%, low or marginal health literacy N/A vs. 4.4%.  Patients had a mean duration of disease of 9.6 year (range < 1 -30) and previous had used a mean of 3 disease modifying drugs (range 1-8). A two-way ANOVA performed on mean satisfaction with risk communication scores did not disclose a significant effect of participant type [F (1, 174) = .109, p = .742, p2 = .001)].  Participants across conditions overestimated the rate of progression by 19 percentage points (M response of 34.4%, SD 29.7).  The two-way ANOVA of mean verbatim recall indicated a significant effect of information format, F (3, 174) =2.774, p<0.023, p2 = .053. The main effect of participant type however was not significant, F (1, 174) = .003, p = .955, p2 > .001.

Conclusion:   Graphic elements improved the understanding of disease progression in participants unfamiliar with the disease as well as in RA patients.  Our results indicate that testing decision aid components with non-patients may provide data generalizable to patient populations from more convenient samples than patients.  We demonstrate that it is not only feasible to conduct message framing experiments with patients in a clinical setting, but that they were very interested in contributing to the development of medication patient decision aids.