1. |
- Backlund, Lars G., et al.
(author)
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Improving Fast and Frugal Modeling in Relation to Regression Analysis : Test of 3 Models for Medical Decision Making
- 2009
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In: Medical decision making. - : Sage Publications. - 0272-989X .- 1552-681X. ; 29:1, s. 140-148
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Journal article (peer-reviewed)abstract
- Background. A matching heuristic (MH) model of decision makinghas been evaluated previously in a series of studies on medicaldecision making. The authors' purpose is to evaluate an extendedMH model that considers the prevalence of cue values. Methods.Data from 2 previous studies were reanalyzed, one on judgmentsregarding drug treatment of hyperlipidemia and the other ondiagnosing heart failure. The original MH model and the extendedMH model were compared with logistic regression (LR) in termsof fit to actual judgments, number of cues, and the extent towhich the cues were consistent with clinical guidelines. Results. There was a slightly better fit with LR compared with MH. Theextended MH model gave a significantly better fit than the originalMH model in the drug treatment task. In the diagnostic task,the number of cues was significantly lower in the MH modelscompared to LR, whereas in the therapeutic task, LR could beless or more frugal than the matching heuristic models dependingon the significance level chosen for inclusion of cues. Forthe original MH model, but not for the extended MH model orLR, the most important cues in the drug treatment task wereoften used in a direction contrary to treatment guidelines.Conclusions. The extended MH model represents an improvementin that prevalence of cue values is adequately taken into account,which in turn may result in better fit and in better agreementwith medical guidelines in the evaluation of cues.
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2. |
- Bleichrodt, Han, et al.
(author)
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An Experimental Test of a Theoretical Foundation for Rating-scale Valuations
- 1997
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In: Medical decision making. - : SAGE. - 1552-681X .- 0272-989X. ; 17:2, s. 208-216
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Journal article (peer-reviewed)abstract
- A major advantage of using a rating scale in health-utility measurement is its practical applicability: the method is relatively easy to understand, and various health states can be assessed simultaneously. However, a theoretical foundation for rating-scale valuations has not been established. The primary aim of this paper is to present a theoretical foundation for rating-scale valuations based on the theory of measurable value functions and to provide a consistency test to see whether rating-scale valuations do indeed elicit a measurable value function. If rating-scale valuations elicit a measurable value function, then Dyer and Sarin have shown how they are related to von Neumann-Morgenstern (vNM) utilities. The appropriate technique to measure vNM utilities is the standard gamble. Torrance has suggested that rating-scale valuations and standard-gamble valuations are related by a power function. A secondary aim of this paper is to examine the relationship between rating-scale valuations and standard-gamble valuations hypothesized by Torrance. An experiment was designed to test consistency of rating-scale valuations and the relationship between rating-scale valuations and standard-gamble valuations. The experiment tested whether rating-scale valuations are independent of the context in which they are elicited, as they should be if they elicit points on a measurable value function. 80 Swedish and 92 Dutch respondents participated in the experiment. The results showed that rating-scale valuations depend on the number of preferred alternatives in the task and thus violate a basic property of measurable value functions. The estimation of the power function did not result in stable results: parameter estimates varied, in some cases there was indication of misspecification, and in most cases there was indication of heteroskedastic errors. The implications of these findings for the common use of rating-scale valuations in cost-utility analysis are serious: the dependency of the rating-scale valuations on the other health states included in the task casts serious doubts on the validity of the rating-scale method. Key words: QALYs; rating scale; cost-utility analysis; medical decision making. (Med Decis Making 1997;17:208-216))
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3. |
- Bleichrodt, Han, et al.
(author)
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The Validity of QALYs : An Experimental Test of Constant Proportional Tradeoff and Utility Independence
- 1997
-
In: Medical decision making. - 1552-681X .- 0272-989X. ; 17:1, s. 21-32
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Journal article (peer-reviewed)abstract
- Pliskin, Shepard, and Weinstein identified three preference conditions that ensure that quality-adjusted life years (QALYs) represent preferences over gambles over chronic health profiles. This paper presents an experimental test of the descriptive validity of two of these preference assumptions: utility independence and constant proportional tradeoff. Eighty students at the Stockholm School of Economics and 92 students at Erasmus University Rotterdam participated in the experiment. The results of the ex periment support the descriptive validity of constant proportional tradeoff: both within groups and between groups constant proportional tradeoff could not be rejected. The results are less supportive of the descriptive validity of utility independence. Within- groups utility independence was rejected. Between-groups utility independence could not be rejected, but this may have been due to a lack of statistical power. Analysis of the individual responses revealed that without adjustment for imprecision of preference, 39 respondents (22.8%) satisfied constant proportional tradeoff. Twenty-three respon dents (13.4%) satisfied utility independence without adjustment for imprecision of pref erence. However, because of the relative unfamiliarity of the respondents with both the health states to be evaluated and the methods of health-state-utility measurement, it is likely that the respondents' preferences were imprecise. Adjusted for imprecision of preference, the upper estimates of the proportions of respondents who satisfied constant proportional tradeoff and utility independence, respectively, were 90.1% (155 respondents) and 75.6% (130 respondents). Pliskin et al. further derived that if an individual's preferences satisfy both constant proportional tradeoff and utility indepen dence, then these preferences can be represented by a more general, risk-adjusted QALY model. Without adjustment for imprecision of preference, ten respondents (5.8%) satisfied both constant proportional tradeoff and utility independence. Adjusted for imprecision of preference, the upper estimate of the proportion of respondents who satisfied both constant proportional tradeoff and utility independence was 68.6% (118 respondents). The results of this study indicate that constant proportional tradeoff holds approximately. The evidence is much weaker for utility independence, however. This has important implications for the use of QALY-type measures in medical decision making. Key words: QALYs; health utility measurements; medical decision making; individual preferences. (Med Decis Making 1996;17:21-32)
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4. |
- Borgquist, Lars, et al.
(author)
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The Relationship between Health-state Utilities and the SF-12 in a General Population
- 1999
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In: Medical decision making. - : SAGE. - 1552-681X .- 0272-989X. ; 19:2, s. 128-140
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Journal article (peer-reviewed)abstract
- It would be a major advance if quality-of-life instruments could be translated into health- state utilities. The aim with this study was to investigate the relationship between the SF-12 and health-state utilities, based on responses to a postal questionnaire sent to a random sample of 8,000 inhabitants, aged 20-84 years, in the general population. The questionnaire included the SF-12, a rating-scale (RS) question, and a time-tradeoff (TTO) question; the response rate was 68%. Age, gender, and the 12 items of the SF- 12 were used as explanatory variables in a linear regression analysis of the health- state utilities. The regression models explained about 50% of the variance in the RS answers and about 25% of the variance in the TTO answers. Most of the SF-12 items were related to the health-state utilities in the expected ways, with especially strong results for the RS method. The results suggest that the SF-12 can be converted to health-state utilities, but that further work is needed to reliably estimate the conversion function. Key words: health status; SF-12; rating scale; time-tradeoff; health-related quality of life; health-state utilities; population study. (Med Decis Making 1999;19:128- 140)
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5. |
- Cao, Qi, et al.
(author)
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Continuous-Time Semi-Markov Models in Health Economic Decision Making: An Illustrative Example in Heart Failure Disease Management
- 2016
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In: Medical decision making. - : SAGE PUBLICATIONS INC. - 0272-989X .- 1552-681X. ; 36:1, s. 59-71
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Journal article (peer-reviewed)abstract
- Continuous-time state transition models may end up having large unwieldy structures when trying to represent all relevant stages of clinical disease processes by means of a standard Markov model. In such situations, a more parsimonious, and therefore easier-to-grasp, model of a patients disease progression can often be obtained by assuming that the future state transitions do not depend only on the present state (Markov assumption) but also on the past through time since entry in the present state. Despite that these so-called semi-Markov models are still relatively straightforward to specify and implement, they are not yet routinely applied in health economic evaluation to assess the cost-effectiveness of alternative interventions. To facilitate a better understanding of this type of model among applied health economic analysts, the first part of this article provides a detailed discussion of what the semi-Markov model entails and how such models can be specified in an intuitive way by adopting an approach called vertical modeling. In the second part of the article, we use this approach to construct a semi-Markov model for assessing the long-term cost-effectiveness of 3 disease management programs for heart failure. Compared with a standard Markov model with the same disease states, our proposed semi-Markov model fitted the observed data much better. When subsequently extrapolating beyond the clinical trial period, these relatively large differences in goodness-of-fit translated into almost a doubling in mean total cost and a 60-d decrease in mean survival time when using the Markov model instead of the semi-Markov model. For the disease process considered in our case study, the semi-Markov model thus provided a sensible balance between model parsimoniousness and computational complexity.
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6. |
- Caster, Ola, et al.
(author)
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Quantitative Benefit-Risk Assessment Using Only Qualitative Information on Utilities
- 2012
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In: Medical decision making. - 0272-989X .- 1552-681X. ; 32:6, s. E1-E15
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Journal article (peer-reviewed)abstract
- Background: Utilities of pertinent clinical outcomes are crucial variables for assessing the benefits and risks of drugs, but numerical data on utilities may be unreliable or altogether missing. We propose a method to incorporate qualitative information into a probabilistic decision analysis framework for quantitative benefit-risk assessment. Objective: To investigate whether conclusive results can be obtained when the only source of discriminating information on utilities is widely agreed upon qualitative relations, for example, ''sepsis is worse than transient headache'' or ''alleviation of disease is better without than with complications.'' Method: We used the structure and probabilities of 3 published models that were originally evaluated based on the standard metric of quality-adjusted life years (QALYs): terfenadine versus chlorpheniramine for the treatment of allergic rhinitis, MCV4 vaccination against meningococcal disease, and alosetron for irritable bowel syndrome. For each model, we identified clinically straightforward qualitative relations among the outcomes. Using Monte Carlo simulations, the resulting utility distributions were then combined with the previously specified probabilities, and the rate of preference in terms of expected utility was determined for each alternative. Results: Our approach conclusively favored MCV4 vaccination, and it was concordant with the QALY assessments for the MCV4 and terfenadine versus chlorpheniramine case studies. For alosetron, we found a possible unfavorable benefit-risk balance for highly risk-averse patients not identified in the original analysis. Conclusion: Incorporation of widely agreed upon qualitative information into quantitative benefit-risk assessment can provide for conclusive results. The methods presented should prove useful in both population and individual-level assessments, especially when numerical utility data are missing or unreliable, and constraints on time or money preclude its collection.
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7. |
- DiSantostefano, Rachael L., et al.
(author)
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Can the General Public Be a Proxy for an "At-Risk" Group in a Patient Preference Study? : A Disease Prevention Example in Rheumatoid Arthritis
- 2024
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In: Medical decision making. - : Sage Publications. - 0272-989X .- 1552-681X. ; 44:2, s. 189-202
-
Journal article (peer-reviewed)abstract
- BackgroundWhen selecting samples for patient preference studies, it may be difficult or impractical to recruit participants who are eligible for a particular treatment decision. However, a general public sample may not be an appropriate proxy.ObjectiveThis study compares preferences for rheumatoid arthritis (RA) preventive treatments between members of the general public and first-degree relatives (FDRs) of confirmed RA patients to assess whether a sample of the general public can be used as a proxy for FDRs.MethodsParticipants were asked to imagine they were experiencing arthralgia and had screening tests indicating a 60% chance of developing RA within 2 yrs. Using a discrete choice experiment, participants were offered a series of choices between no treatment and 2 unlabeled hypothetical treatments to reduce the risk of RA. To assess data quality, time to complete survey sections and comprehension questions were assessed. A random parameter logit model was used to obtain attribute-level estimates, which were used to calculate relative importance, maximum acceptable risk (MAR), and market shares of hypothetical preventive treatments.ResultsThe FDR sample (n = 298) spent more time completing the survey and performed better on comprehension questions compared with the general public sample (n = 982). The relative importance ranking was similar between the general public and FDR participant samples; however, other relative preference measures involving weights including MARs and market share differed between groups, with FDRs having numerically higher MARs.ConclusionIn the context of RA prevention, the general public (average risk) may be a reasonable proxy for a more at-risk sample (FDRs) for overall relative importance ranking but not weights. The rationale for a proxy sample should be clearly justified.HighlightsParticipants from the general public were compared to first-degree relatives on their preferences for rheumatoid arthritis (RA) preventive treatments using a discrete choice experiment.Preferences were similar between groups in terms of the most important and least important attributes of preventive treatments, with effectiveness being the most important attribute. However, relative weights differed.Attention to the survey and predicted market shares of hypothetical RA preventive treatments differed between the general public and first-degree relatives.The general public may be a reasonable proxy for an at-risk group for patient preferences ranks but not weights in the disease prevention context; however, care should be taken in sample selection for patient preference studies when choosing nonpatients.
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8. |
- Heintz, Emelie, 1981-, et al.
(author)
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The impact of patients' subjective life expectancy on time trade-off valuations
- 2013
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In: Medical decision making. - : SAGE Publications (UK and US). - 0272-989X .- 1552-681X. ; 33:2, s. 261-270
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Journal article (peer-reviewed)abstract
- Background. Quality-adjusted life-year (QALY) calculations in economic evaluations are typically based on general public or patient health state valuations elicited with the time tradeoff method (TTO). Such health state valuations elicited among the general public have been shown to be affected by respondents subjective life expectancy (SLE). This suggests that TTO exercises based on time frames other than SLE may lead to biased estimates. It has not yet been investigated whether SLE also affects patient valuations. Objective. To empirically investigate whether patients SLE affects TTO valuations of their current health state. Methods. Patients with different severities of diabetic retinopathy were asked in a telephone interview to value their own health status using TTO. The TTO time frame (t) presented was based on age- and sex-dependent actuarial life expectancy. Patients were then asked to state their SLE. Simple and multiple regression techniques were used to assess the effect of the patients SLE on their TTO responses. Results. In total, 145 patients completed the telephone interview. Patients TTO values were significantly influenced by their SLE. The TTO value decreased linearly with every additional year of difference between t and the patients SLE; that is, patients were more willing to give up years the shorter their SLE compared with t. Conclusion. Patients SLE influenced their TTO valuations, suggesting that respondents SLE may be the most appropriate time frame to use in TTO exercises in patients. The use of other time periods may bias the TTO valuations, as the respondents may experience the presented time frame as a gain or a loss. The effect seems to be larger in patient valuations than in general public valuations.
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9. |
- Johannesen, Kasper, et al.
(author)
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Subcategorizing the Expected Value of Perfect Implementation to Identify When and Where to Invest in Implementation Initiatives
- 2020
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In: Medical decision making. - : Sage Publications. - 0272-989X .- 1552-681X. ; 40:3, s. 327-338
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Journal article (peer-reviewed)abstract
- Purpose. Clinical practice variations and low implementation of effective and cost-effective health care technologies are a key challenge for health care systems and may lead to suboptimal treatment and health loss for patients. The purpose of this work was to subcategorize the expected value of perfect implementation (EVPIM) to enable estimation of the absolute and relative value of eliminating slow, low, and delayed implementation. Methods. Building on the EVPIM framework, this work defines EVPIM subcategories to estimate the expected value of eliminating slow, low, or delayed implementation. The work also shows how information on regional implementation patterns can be used to estimate the value of eliminating regional implementation variation. The application of this subcategorization is illustrated by a case study of the implementation of an antiplatelet therapy for the secondary prevention after myocardial infarction in Sweden. Incremental net benefit (INB) estimates are based on published cost-effectiveness assessments and a threshold of SEK 250,000 (22,300) pound per quality-adjusted life year (QALY). Results. In the case study, slow, low, and delayed implementation was estimated to represent 22%, 34%, and 44% of the total population EVPIM (2941 QALYs or SEK 735 million), respectively. The value of eliminating implementation variation across health care regions was estimated to 39% of total EVPIM (1138 QALYs). Conclusion. Subcategorizing EVPIM estimates the absolute and relative value of eliminating different parts of suboptimal implementation. By doing so, this approach could help decision makers to identify which parts of suboptimal implementation are contributing most to total EVPIM and provide the basis for assessing the cost and benefit of implementation activities that may address these in future implementation of health care interventions.
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10. |
- Johannesson, Magnus, et al.
(author)
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Are Healthy-years Equivalents an Improvement over Quality-adjusted Life Years?
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In: Medical decision making. - 1552-681X .- 0272-989X. ; 13:4, s. 281-286
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Journal article (peer-reviewed)abstract
- The construct of the healthy-years equivalent (HYE) has been proposed as an alternative to the quality-adjusted life year (QALY) on the grounds that it avoids certain restrictive assumptions about preferences and also incorporates attitudes toward risk. The authors review the construct of the QALY, including both the commonly used risk-neutral formulation and the more general formulation that permits risk aversion (or risk preference) with respect to remaining life years. They show that the HYE adds flexibility to the risk-neutral form of the QALY by permitting the rate of tradeoff between life years and quality of life to depend on the life span, albeit at the cost of eliciting numerous additional time-tradeoff assessments. However, the claim that the HYE incorporates attitudes toward risk is incorrect, and the proposed two-stage procedure to measure HYEs is neither necessary nor sufficient to in corporate attitudes toward risk. In fact, the HYE assumes risk neutrality with respect to healthy years of life and, therefore, is less suitable for decisions under uncertainty than is the general (risk-averse) form of the QALY. Key words: quality-adjusted life years; healthy- years equivalents; economic evaluation; medical decision making; individual preferences; time-tradeoff; standard gamble; utility theory. (Med Decis Making 1993;13:281-286)
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11. |
- Johannesson, Magnus, et al.
(author)
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Economics, Pharmaceuticals, and Pharmacoeconomics
- 1998
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In: Medical decision making. - : SAGE. - 1552-681X .- 0272-989X. ; 18:2_suppl, s. S1-S3
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Journal article (peer-reviewed)abstract
- Pharmacoeconomics, as the compound name suggests, is the application of principles of economic enquiry to pharmaceuticals. Although the label "pharmacoeconomics" has been used only for the last ten years or so, already there are a journal of the same name publishing monthly issues and textbooks on the topic. Graduate programs and fellowships in pharmacoeconomics are flourishing around the world, and professional societies such as the Association for Outcomes Research and Pharmacoeconomics (APOR) have appeared. The daily mail is not complete without an announcement for another pharmacoeconomics conference. So what is pharmacoeconomics all about, and why does it rate a special issue of MDM?
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12. |
- Johannesson, Magnus, et al.
(author)
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Incorporating Future Costs in Medical Cost-Effectiveness Analysis : Implications for the Cost-Effectiveness of the Treatment of Hypertension
- 1997
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In: Medical decision making. - : SAGE. - 1552-681X .- 0272-989X. ; 17:4, s. 382-389
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Journal article (peer-reviewed)abstract
- It has been shown that the difference between consumption and production during life years gained should be included as a cost in cost-effectiveness analysis. In this study the authors estimate the impact of including these future costs on the cost-effective ness of the treatment of hypertension in Sweden. The cost per quality-adjusted life year (QALY) gained changes little among young men and women due to the addition of future costs, but increases by about $14,000 for middle-aged men and women and about $27,000 for older men and women. When future costs are not included, the cost per QALY gained is generally lowest among older men and women, but when future costs are included, the cost per QALY gained is generally lowest among middle-aged men and women. The authors conclude that the total resource consequences of changes in mortality should be routinely considered in cost-effectiveness analyses. Key words: Cost-effectiveness analysis; economic evaluation; costs; societal per spective. (Med Decis Making 1997;17:382-389)
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13. |
- Johannesson, Magnus
(author)
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The Impact of Age on the Cost - Effectiveness of Hypertension Treatment : An Analysis of Randomized Drug Trials
- 1994
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In: Medical decision making. - 1552-681X .- 0272-989X. ; 14:3, s. 236-244
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Journal article (peer-reviewed)abstract
- The aim of this study was to investigate whether any consistent pattern exists with respect to the cost-effectiveness of hypertension treatment and age, based on the results of ran domized drug trials. Data about age, entry diastolic blood pressure, and relative risks of coronary heart disease (CHD) and stroke from 19 randomized trials were used to derive point estimates of the cost-effectiveness of each trial. The relationship between age and cost per life-year gained was then estimated by regression analysis, controlling for entry diastolic blood pressure. The regression analysis shows a statistically significant average decrease in the cost per life-year gained of about SEK 15,000 per year of older age for both men and women ($1 = SEK 6). Sensitivity analysis showed that the improvement in cost- effectiveness with age was stable towards various assumptions, but that the magnitude of the improvement varied greatly with the discount rate. Based on the results of randomized drug trials, it is concluded that the cost-effectiveness of hypertension treatment improves with patient age for both men and women. Key words: hypertension; drug treatment; cost- effectiveness; age; economic evaluation. (Med Decis Making 1994;14:236-244)
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14. |
- Kartman, Bernt, et al.
(author)
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Health state utilities in gastroesophageal reflux disease patients with heartburn: a study in Germany and Sweden
- 2004
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In: Medical decision making. - : SAGE. - 1552-681X .- 0272-989X. ; 24:1, s. 40-52
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Journal article (peer-reviewed)abstract
- The objectives of this study were to assess health state utilities in patients with gastroesophageal reflux disease with heartburn and to analyze if severity and annual frequency of heartburn can predict utilities. A total of 1011 patients in Germany and Sweden participated in telephone interviews, where utilities were assessed using the rating scale (RS), EQ-5D, time trade-off (TTO) and standard gamble (SG) instruments. The average RS, EQ-5D, TTO, and SG utilities were 0.69, 0.70, 0.88, and 0.89, respectively. Linear regression analyses showed that the EQ-5D and RS utilities were negatively and significantly related to the severity and frequency of heartburn. The EQ-5D and RS results indicate that patients with heartburn assign their health states substantial disutility and that it is feasible to estimate regression equations to predict utilities from heartburn-specific variables. In the TTO and SG analyses, the impact of heartburn was in the expected direction but smaller and in general not significant.
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15. |
- Kartman, Bernt, et al.
(author)
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Willingness to Pay for Reductions in Angina Pectoris Attacks
- 1996
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In: Medical decision making. - : SAGE. - 1552-681X .- 0272-989X. ; 16:3, s. 248-253
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Journal article (peer-reviewed)abstract
- To compare the costs of health care programs with the benefits, the values of changes in health status must be expressed in monetary terms. The development of methods to estimate willingness to pay for changes in health status is therefore of interest. This paper reports the results of a contingent valuation study measuring willingness to pay for reductions in angina pectoris attacks. An innovative study design allowed analysis of the data on willingness to pay using two approaches, a binary question and a bid ding-game technique. Percentage reductions in anginal attacks were varied randomly in different subsamples, and data were collected about angina pectoris status, attack rate, and income to test the internal validity of the contingent valuation method. Will ingness to pay for a 50% reduction in the attack rate for three months was estimated to be about SEK 2,500 ($345) with the binary approach, and about SEK 2,100 ($290) using the bidding-game technique. Regression analyses showed that income, angina pectoris status, attack rate, and percentage reduction in attack rate were all related to willingness to pay, in agreement with the authors' hypothesis. Key words: willingness to pay; contingent valuation; angina pectoris; cost-benefit analysis. (Med Decis Mak ing 1996;16:248-253)
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16. |
- Kim, David D., et al.
(author)
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Development and Validation of the US Diabetes, Obesity, Cardiovascular Disease Microsimulation (DOC-M) Model : Health Disparity and Economic Impact Model
- 2023
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In: Medical decision making. - 0272-989X .- 1552-681X. ; 43:7-8, s. 930-948
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Journal article (peer-reviewed)abstract
- BACKGROUND: Few simulation models have incorporated the interplay of diabetes, obesity, and cardiovascular disease (CVD); their upstream lifestyle and biological risk factors; and their downstream effects on health disparities and economic consequences.METHODS: We developed and validated a US Diabetes, Obesity, Cardiovascular Disease Microsimulation (DOC-M) model that incorporates demographic, clinical, and lifestyle risk factors to jointly predict overall and racial-ethnic groups-specific obesity, diabetes, CVD, and cause-specific mortality for the US adult population aged 40 to 79 y at baseline. An individualized health care cost prediction model was further developed and integrated. This model incorporates nationally representative data on baseline demographics, lifestyle, health, and cause-specific mortality; dynamic changes in modifiable risk factors over time; and parameter uncertainty using probabilistic distributions. Validation analyses included assessment of 1) population-level risk calibration and 2) individual-level risk discrimination. To illustrate the application of the DOC-M model, we evaluated the long-term cost-effectiveness of a national produce prescription program.RESULTS: Comparing the 15-y model-predicted population risk of primary outcomes among the 2001-2002 National Health and Nutrition Examination Survey (NHANES) cohort with the observed prevalence from age-matched cross-sectional 2003-2016 NHANES cohorts, calibration performance was strong based on observed-to-expected ratio and calibration plot analysis. In most cases, Brier scores fell below 0.0004, indicating a low overall prediction error. Using the Multi-Ethnic Study of Atherosclerosis cohorts, the c-statistics for assessing individual-level risk discrimination were 0.85 to 0.88 for diabetes, 0.93 to 0.95 for obesity, 0.74 to 0.76 for CVD history, and 0.78 to 0.81 for all-cause mortality, both overall and in three racial-ethnic groups. Open-source code for the model was posted at https://github.com/food-price/DOC-M-Model-Development-and-Validation.CONCLUSIONS: The validated DOC-M model can be used to examine health, equity, and the economic impact of health policies and interventions on behavioral and clinical risk factors for obesity, diabetes, and CVD.HIGHLIGHTS: We developed a novel microsimula'tion model for obesity, diabetes, and CVD, which intersect together and - critically for prevention and treatment interventions - share common lifestyle, biologic, and demographic risk factors.Validation analyses, including assessment of (1) population-level risk calibration and (2) individual-level risk discrimination, showed strong performance across the overall population and three major racial-ethnic groups for 6 outcomes (obesity, diabetes, CVD, and all-cause mortality, CVD- and DM-cause mortality)This paper provides a thorough explanation and documentation of the development and validation process of a novel microsimulation model, along with the open-source code (https://github.com/food-price/ DOCM_validation) for public use, to serve as a guide for future simulation model assessments, validation, and implementation.
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17. |
- Kip, Michelle M. A., et al.
(author)
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Toward Alignment in the Reporting of Economic Evaluations of Diagnostic Tests and Biomarkers: The AGREEDT Checklist
- 2018
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In: Medical decision making. - : SAGE PUBLICATIONS INC. - 0272-989X .- 1552-681X. ; 38:7, s. 778-788
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Journal article (peer-reviewed)abstract
- Objectives. General frameworks for conducting and reporting health economic evaluations are available but not specific enough to cover the intricacies of the evaluation of diagnostic tests and biomarkers. Such evaluations are typically complex and model-based because tests primarily affect health outcomes indirectly and real-world data on health outcomes are often lacking. Moreover, not all aspects relevant to the evaluation of a diagnostic test may be known and explicitly considered for inclusion in the evaluation, leading to a loss of transparency and replicability. To address this challenge, this study aims to develop a comprehensive reporting checklist. Methods. This study consisted of 3 main steps: 1) the development of an initial checklist based on a scoping review, 2) review and critical appraisal of the initial checklist by 4 independent experts, and 3) development of a final checklist. Each item from the checklist is illustrated using an example from previous research. Results. The scoping review followed by critical review by the 4 experts resulted in a checklist containing 44 items, which ideally should be considered for inclusion in a model-based health economic evaluation. The extent to which these items were included or discussed in the studies identified in the scoping review varied substantially, with 14 items not being mentioned in 47 (75%) of the included studies. Conclusions. The reporting checklist developed in this study may contribute to improved transparency and completeness of model-based health economic evaluations of diagnostic tests and biomarkers. Use of this checklist is therefore encouraged to enhance the interpretation, comparability, andindirectlythe validity of the results of such evaluations.
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18. |
- Lytsy, Per, et al.
(author)
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Views on Treatment Necessity, Harm, and Benefits in Patients Using Statins
- 2010
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In: Medical decision making. - 0272-989X .- 1552-681X. ; 30:5, s. 594-609
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Journal article (peer-reviewed)abstract
- BACKGROUNDPatients with dyslipidemia and high overall risk of ischemic heart disease are those most likely to benefit from treatment with statins. The objective of this study was to investigate patients' views of the necessity, harm, and expected benefits of their statin treatment, as well as factors associated with these treatment beliefs. One main objective was to investigate whether cardiovascular risk level and previous coronary heart disease affect the way patients view these different aspects of their medication.METHODSA total of 829 statin users were recruited while visiting a pharmacy to collect their statin medication (response rate, 69.4%). Patients returned a questionnaire assessing their medical history, concurrent risk status, social demographic factors, as well as their views and expectations regarding their statin treatment. RESULTS: Previous ischemic heart disease, or high risk of such disease, was not associated with a more favorable notion on statin treatment. Having an internal health locus of control as well as being satisfied with the physician's treatment explanation were factors associated with more positive views on expected treatment effect. The views on necessity, harm, and treatment benefit were closely associated with each other.CONCLUSIONThe main findings in this study suggest that cardiovascular risk level and previous coronary heart disease are not associated with the way patients value potential benefits of statin treatment. Patients' views of the treatment's necessity, harm, and benefits do not seem to be independent dimensions of patient beliefs but rather represent one overall question: is this good for me?
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19. |
- Maguire, Allegra, et al.
(author)
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COVID-19 and Politically Motivated Reasoning
- 2022
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In: Medical decision making. - : Sage Publications Inc. - 0272-989X .- 1552-681X. ; 42:8, s. 1078-1086
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Journal article (peer-reviewed)abstract
- Background. During the COVID-19 pandemic, the world witnessed a partisan segregation of beliefs toward the global health crisis and its management. Politically motivated reasoning, the tendency to interpret information in accordance with individual motives to protect valued beliefs rather than objectively considering the facts, could represent a key process involved in the polarization of attitudes. The objective of this study was to explore politically motivated reasoning when participants assess information regarding COVID-19. Design. We carried out a preregistered online experiment using a diverse sample (N = 1500) from the United States. Both Republicans and Democrats assessed the same COVID-19-related information about the health effects of lockdowns, social distancing, vaccination, hydroxychloroquine, and wearing face masks. Results. At odds with our prestated hypothesis, we found no evidence in line with politically motivated reasoning when interpreting numerical information about COVID-19. Moreover, we found no evidence supporting the idea that numeric ability or cognitive sophistication bolster politically motivated reasoning in the case of COVID-19. Instead, our findings suggest that participants base their assessment on prior beliefs of the matter. Conclusions. Our findings suggest that politically polarized attitudes toward COVID-19 are more likely to be driven by lack of reasoning than politically motivated reasoning-a finding that opens potential avenues for combating political polarization about important health care topics.
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20. |
- Meltzer, David, et al.
(author)
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Inconsistencies in the "Societal Perspective" on Costs of the Panel on Cost-Effectiveness in Health and Medicine
- 1999
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In: Medical decision making. - : SAGE. - 1552-681X .- 0272-989X. ; 19:4, s. 371-377
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Journal article (peer-reviewed)abstract
- A key recommendation of the recent Panel on Cost-Effectiveness in Health and Med icine was that cost-effectiveness analyses be carried out from a societal perspective. The authors show that two of the Panel's recommendations concerning costs are not consistent with a societal perspective, and how to correct those inconsistencies. In its recommendations concerning costs resulting from morbidity, the Panel advises ex cluding lost income from costs in the belief that individuals take income changes into account when they respond to the quality-of-life questions that are used to calculate quality-adjusted life years (QALYs). It is shown that even if individuals do consider income changes in responding to these quality-of-life questions, this recommendation would seriously underestimate production losses due to morbidity, since individuals do not bear a major part of lost production. In its recommendations concerning costs resulting from mortality, the Panel does not require that health care costs for "unre lated" illness and non-health care consumption and production during added life years be included in the Reference Case. It is shown that omitting these costs will seriously distort comparisons of programs at different ages and favor programs that extend life over those that improve quality of life. This can be corrected by including total con sumption minus production in added life-years among costs. Key words: cost-effec tiveness analysis; societal perspective; public policy; resource allocation; Panel on Cost-Effectiveness in Health and Medicine. (Med Decis Making 1999; 19:371-377)
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21. |
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22. |
- Persson, Emil, et al.
(author)
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Discrepancy between Health Care Rationing at the Bedside and Policy Level
- 2018
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In: Medical decision making. - : SAGE PUBLICATIONS INC. - 0272-989X .- 1552-681X. ; 38:7, s. 881-887
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Journal article (peer-reviewed)abstract
- Background. Whether doctors at the bedside level should be engaged in health care rationing is a controversial topic that has spurred much debate. From an empirical point of view, a key issue is whether there exists a behavioral difference between rationing at the bedside and policy level. Psychological theory suggests that we should indeed expect such a difference, but existing empirical evidence is inconclusive. Objective. To explore whether rationing decisions taken at the bedside level are different from rationing decisions taken at the policy level. Method. Behavioral experiment where participants (n = 573) made rationing decisions in hypothetical scenarios. Participants (medical and nonmedical students) were randomly assigned to either a bedside or a policy condition. Each scenario involved 1 decision, concerning either a life-saving medical treatment or a quality-of-life improving treatment. All scenarios were identical across the bedside and policy condition except for the level of decision making. Results. We found a discrepancy between health care rationing at policy and bedside level for scenarios involving life-saving decisions, where subjects rationed treatments to a greater extent at the policy level compared to bedside level (35.6% v. 29.3%, P = 0.001). Medical students were more likely to ration care compared to nonmedical students. Follow-up questions showed that bedside rationing was more emotionally burdensome than rationing at the policy level, indicating that psychological factors likely play a key role in explaining the observed behavioral differences. We found no difference in rationing between bedside and policy level for quality-of-life improving treatments (54.6% v. 55.7%, P = 0.507). Conclusions. Our results indicate a robust bedside effect in the life-saving domain of health care rationing decisions, thereby adding new insights to the understanding of the malleability of preferences related to resource allocation.
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23. |
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24. |
- Strand, Liam, 1996-, et al.
(author)
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Withdrawing versus Withholding Treatments in Medical Reimbursement Decisions: A Study on Public Attitudes
- 2024
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In: Medical decision making. - : Sage Publications. - 0272-989X .- 1552-681X. ; 44:6, s. 641-648
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Journal article (peer-reviewed)abstract
- BackgroundThe use of policies in medical treatment reimbursement decisions, in which only future patients are affected, prompts a moral dilemma: is there an ethical difference between withdrawing and withholding treatment?DesignThrough a preregistered behavioral experiment involving 1,067 participants, we tested variations in public attitudes concerning withdrawing and withholding treatments at both the bedside and policy levels.ResultsIn line with our first hypothesis, participants were more supportive of rationing decisions presented as withholding treatments compared with withdrawing treatments. Contrary to our second prestated hypothesis, participants were more supportive of decisions to withdraw treatment made at the bedside level compared with similar decisions made at the policy level.ImplicationsOur findings provide behavioral insights that help explain the common use of policies affecting only future patients in medical reimbursement decisions, despite normative concerns of such policies. In addition, our results may have implications for communication strategies when making decisions regarding treatment reimbursement.
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25. |
- Tinghög, Gustav, 1979-, et al.
(author)
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Medical Decision Style and COVID-19 Behavior
- 2022
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In: Medical decision making. - : Sage Publications. - 0272-989X .- 1552-681X. ; 42:6, s. 776-782
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Journal article (peer-reviewed)abstract
- Given the flood of health-related information stirred up by the coronavirus disease 2019 (COVID-19) pandemic, it is important to understand the factors that influence people to engage in protective public health measures so that medical communication can be tailored to be effective. Following the idea that people have a general inclination toward health care utilization, which is either more passive (i.e., medical minimizer) or more aggressive (i.e., medical maximizer), we assess if this inclination extends to being more or less willing to engage in protective public health behavior. We investigate the effect of individual differences in medical minimizing and medical maximizing orientation on COVID-19-related protective behaviors and attitudes. We used the validated Medical Maximizer-Minimizer Scale (MMS) and surveyed a diverse opt-in sample of the Swedish population (n = 806). Our results show that the MMS significantly predicts a wide range of self-reported behaviors and attitudes in relation to COVID-19. Participants with a stronger minimization orientation were significantly less likely to practice social distancing, follow hygiene recommendations, and be supportive of strict COVID-19 policies. Participants with a stronger maximization orientation had a larger discrepancy between perceived own risk and others getting infected. Thus, they perceived themselves as being less at risk for getting infected compared to the average person. Our findings imply that the MMS can be effectively used to predict who is more or less reluctant to follow public health recommendations. JEL codes: D70 E71 I12 I18
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26. |
- Tinghög, Gustav, 1979-, et al.
(author)
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Medical Homo Ignorans, Shared Decision Making, and Affective Paternalism: Balancing Emotion and Analysis in Health Care Choices
- 2024
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In: Medical decision making. - : Sagamore Publishing. - 0272-989X .- 1552-681X.
-
Journal article (other academic/artistic)abstract
- In shared decision-making (SDM), the role of emotions and information avoidance is crucial yet often overlooked. We highlight three key aspects of how emotions impact medical decision-making that physicians must understand and utilize for SDM to effectively contribute to sense-making: (i) prominence thinking, (ii) risk as feeling versus risk as analysis, and (iii) preferences for more versus less healthcare. We introduce the novel concept of affective paternalism as a tool for physicians to help patients navigate their emotions by providing not only factual information but also emotional support and guidance. This approach involves recognizing and addressing patients' fears, hopes, and anxieties, thereby helping them process information more comprehensively. By acknowledging and addressing the emotional components inherent in medical decisions, affective paternalism helps patients make more informed and balanced choices, aligning treatment decisions with their overall well-being.
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27. |
- Weinstein, M.C., et al.
(author)
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A Note on QALYs, Time Tradeoff, and Discounting
- 1994
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In: Medical Decision Making. - 1552-681X .- 0272-989X. ; 14:2, s. 188-193
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Journal article (peer-reviewed)abstract
- The theoretical model of QALYs is based on risk neutrality with respect to life years or constant proportional risk posture with respect to life years. It is shown that discounting of QALYs is inconsistent with these assumptions. For discounting to be consistent with individual preferences in a QALY model, individuals have to be risk-neutral with respect to discounted life years or exhibit constant proportional risk posture with respect to discounted life years. For the time-tradeoff method to be consistent with these assumptions, the QALY weights have to be derived by dividing the number of discounted life years in full health by the number of discounted life years in the assessed health states. Key words: quality-adjusted life years; discounting; time tradeoff; standard gamble; individual preferences. (Med Decis Making 1994;14:188-193)
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28. |
- Wiss, Johanna, 1984-, et al.
(author)
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Prioritizing Rare Diseases: Psychological Effects Influencing Medical Decision Making
- 2017
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In: Medical decision making. - : Sage Publications. - 0272-989X .- 1552-681X.
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Journal article (peer-reviewed)abstract
- Background. Measuring societal preferences for rarity has been proposed to determine whether paying pre- mium prices for orphan drugs is acceptable. Objective. To investigate societal preferences for rarity and how psychological factors affect such preferences. Method. A postal survey containing resource allocation dilemmas involving patients with a rare disease and patients with a common disease, equal in severity, was sent out to a randomly selected sample of the population in Sweden (return rate 42.3%, n = 1270). Results. Overall, we found no evidence of a general preference for prioritizing treat- ment of patients with rare disease patients over those with common diseases. When treatment costs were equal, most respondents (42.7%) were indifferent between the choice options. Preferences for prioritizing patients with common diseases over those with rare diseases were more frequently displayed (33.3% v. 23.9%). This tendency was, as expected, amplified when the rare disease was costlier to treat. The share of respondents choosing to treat patients with rare diseases increased when present- ing the patients in need of treatment in relative rather than absolute terms (proportion dominance). Surprisingly, identifiability did not increase preferences for rarity. Instead, identifying the patient with a rare disease made respondents more willing to prioritize the patients with common diseases. Respondents’ levels of education were significantly associated with choice—the lower the level of education, the more likely they were to choose the rare option. Conclusions. We find no support for the existence of a general preference for rarity when setting health care priorities. Psychological effects, especially proportion dominance, are likely to play an important role when pre- ferences for rarity are expressed.
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31. |
- Borg, Sixten, et al.
(author)
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A maximum likelihood estimator of a Markov model for disease activity in Crohn's disease and ulcerative colitis for annually aggregated partial observations.
- 2010
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In: Medical Decision Making. - 1552-681X. ; 30:1, s. 42-132
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Journal article (peer-reviewed)abstract
- Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory bowel diseases that have a remitting, relapsing nature. During relapse, they are treated with drugs and surgery. The present study was based on individual data from patients diagnosed with CD or UC at Herlev University Hospital, Copenhagen, Denmark, during 1991 to 1993. The data were aggregated over calendar years; for each year, the number of relapses and the number of surgical operations were recorded. Our aim was to estimate Markov models for disease activity in CD and UC, in terms of relapse and remission, with a cycle length of 1 month. The purpose of these models was to enable evaluation of interventions that would shorten relapses or postpone future relapses. An exact maximum likelihood estimator was developed that disaggregates the yearly observations into monthly transition probabilities between remission and relapse. These probabilities were allowed to be dependent on the time since start of relapse and on the time since start of remission, respectively. The estimator, initially slow, was successfully optimized to shorten the execution time. The estimated disease activity model for CD fits well to observed data and has good face validity. The disease activity model is less suitable for UC due to its transient nature through the presence of curative surgery.
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32. |
- Bruine de Bruin, Wändi, et al.
(author)
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Effects of anti- vs. pro-vaccine narratives on responses by recipients varying in numeracy : A cross-sectional survey-based experiment
- 2017
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In: Medical Decision Making. - 0272-989X. ; 37:8, s. 860-870
-
Journal article (peer-reviewed)abstract
- Background. To inform their health decisions, patients may seek narratives describing other patients' evaluations of their treatment experiences. Narratives can provide anti-treatment or pro-treatment evaluative meaning that low-numerate patients may especially struggle to derive from statistical information. Here, we examined whether anti-vaccine (v. pro-vaccine) narratives had relatively stronger effects on the perceived informativeness and judged vaccination probabilities reported among recipients with lower (v. higher) numeracy. Methods. Participants (n = 1,113) from a nationally representative US internet panel were randomly assigned to an anti-vaccine or pro-vaccine narrative, as presented by a patient discussing a personal experience, a physician discussing a patient's experience, or a physician discussing the experiences of 50 patients. Anti-vaccine narratives described flu experiences of patients who got the flu after getting vaccinated; pro-vaccine narratives described flu experiences of patients who got the flu after not getting vaccinated. Participants indicated their probability of getting vaccinated and rated the informativeness of the narratives. Results. Participants with lower numeracy generally perceived narratives as more informative. By comparison, participants with higher numeracy rated especially anti-vaccine narratives as less informative. Anti-vaccine narratives reduced the judged vaccination probabilities as compared with pro-vaccine narratives, especially among participants with lower numeracy. Mediation analyses suggested that low-numerate individuals' vaccination probabilities were reduced by anti-vaccine narratives - and, to a lesser extent, boosted by pro-vaccine narratives - because they perceived narratives to be more informative. These findings were similar for narratives provided by patients and physicians. Conclusions. Patients with lower numeracy may rely more on narrative information when making their decisions. These findings have implications for the development of health communications and decision AIDS.
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34. |
- Dewitt, Barry, et al.
(author)
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Perceptions of Clinical Experience and Scientific Evidence in Medical Decision Making : A Survey of a Stratified Random Sample of Swedish Health Care Professionals
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In: Medical Decision Making. - 0272-989X.
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Journal article (peer-reviewed)abstract
- Background: Evidence-based medicine recognizes that clinical expertise gained through experience is essential to good medical practice. However, it is not known what beliefs clinicians hold about how personal clinical experience and scientific knowledge contribute to their clinical decision making and how those beliefs vary between professions, which themselves vary along relevant characteristics, such as their evidence base.Design: We investigate how years in the profession influence health care professionals' beliefs about science and their clinical experience through surveys administered to random samples of Swedish physicians, nurses, occupational therapists, dentists, and dental hygienists. The sampling frame was each profession's most recent occupational registry.Results: Participants (N = 1,627, 46% response rate) viewed science as more important for decision making, more certain, and more systematic than experience. Differences among the professions were greatest for systematicity, where physicians saw the largest gap between the 2 types of knowledge across all levels of professional experience. The effect of years in the profession varied; it had little effect on assessments of importance across all professions but otherwise tended to decrease the difference between assessments of science and experience. Physicians placed the greatest emphasis on science over clinical experience among the 5 professions surveyed.Conclusions: Health care professions appear to share some attitudes toward professional knowledge, despite the variation in the age of the professions and the scientific knowledge base available to practitioners. Training and policy making about clinical decision making might improve by accounting for the ways in which knowledge is understood across the professions.Highlights: Study participants, representing 5 health care professions-medicine, nursing, occupational therapy, dentistry, and dental hygiene-viewed science as more important for decision making, more certain, and more systematic than their personal clinical experience.Of all the professions represented in the study, physicians saw the greatest differences between the 2 types of knowledge.The effect of years of professional experience varied but tended to be small, attenuating the differences seen between science and clinical experience.
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35. |
- Enemark, Ulrika, et al.
(author)
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Implicit discount rates of vascular surgeons in the management of abdominal aortic aneurysms
- 1998
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In: Medical Decision Making. - 1552-681X. ; 18:2, s. 168-177
-
Journal article (peer-reviewed)abstract
- A growing empirical literature has investigated attitudes towards discounting of health benefits with regard to social choices of life-saving and health-improving measures and individuals' time preferences for the management of their own health. In this study, the authors elicited the time preferences of vascular surgeons in the context of management of small abdominal aortic aneurysms, for which the choice between early elective surgery and watchful waiting is not straightforward. They interviewed 25 of a random sample of 30 Swedish vascular surgeons. Considerable variation in the time preferences was found in the choices between watchful waiting and surgical intervention among the otherwise very homogeneous group of surgeons. The discount rates derived ranged from 5.3% to 19.4%. The median discount rate (10.4%) is similar to those usually reported for social choices concerning life-saving measures. The surgeons who were employed in university hospitals had higher discount rates than did their colleagues in county and district hospitals.
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39. |
- Shamir, Raanan, et al.
(author)
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Cost-effectiveness analysis of screening for celiac disease in the adult population.
- 2006
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In: Med Decis Making. - 0272-989X. ; 26:3, s. 282-93
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Journal article (peer-reviewed)abstract
- BACKGROUND: Celiac disease (CD) is common and, when undiagnosed, may result in increased mortality, suggesting that mass screening could be justified. The authors examined the cost-effectiveness (CE) of such an approach, assuming a higher mortality rate in undiagnosed CD and that adhering to a gluten-free diet (GFD) reduces the mortality rate. METHODS: The authors developed a state transition Markov model, evaluating the CE of screening an entire population at the age of 18. Screening strategies included no screening v. screening by IgA antiendomysial antibodies (EMA), IgA human antitissue transglutaminase antibodies (TTG), and TTG verified by EMA. All strategies were examined with and without evaluation for IgA deficiency, and they all included an intestinal biopsy. Effects of variables were examined using sensitivity analysis. Effectiveness was assessed by life expectancy for each strategy and the incremental average CE ratio for each. RESULTS: Base-case analysis revealed US$49,491 and US$572,616 per life year gained for screening compared to no screening using EMA or TTG, respectively. The CE of screening with EMA was most influenced by the prevalence of CD and the standardized mortality ratio (SMR) for untreated CD patients. Screening was cost-effective in populations with a relatively high prevalence of CD or when the SMR for untreated CD patients was higher than 1.5. The model was insensitive to changes in the cost of serological markers and diagnostic endoscopy. CONCLUSION: Assuming an SMR of 1.5 or higher for untreated CD patients, mass screening for CD is cost-effective in populations with a relatively high prevalence of CD over a wide range of ages at screening. From a CE perspective, EMA is the preferred serological marker for mass screening. Screening for CD would be justified only if the uncertainties regarding the validity of our assumptions are substantiated.
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