Peep F. M. Stalmeier

Do Patients With Localized Prostate Cancer Treatment Really Want More Aggressive Treatment

PURPOSEnExamine whether patients with prostate cancer choose the more aggressive of two radiotherapeutic options, whether this choice is reasoned, and what the determinants of the choice are.nnnPATIENTS AND METHODSnOne hundred fifty patients with primary prostate cancer (T(1-3)N(0)M(0)) were informed by means of a decision aid of two treatment options: radiotherapy with 70 Gy versus 74 Gy. The latter treatment is associated with more cure and more toxicity. The patients were asked whether they wanted to choose, and if so which treatment they preferred. They also assigned importance weights to the probability of various outcomes, such as survival, cure and adverse effects. Patients who wanted to choose their own treatment (n = 119) are described here.nnnRESULTSnThe majority of these patients (75%) chose the lower radiation dose. Their choice was highly consistent (P < or = .001), with the importance weights assigned to the probability of survival, cure (odds ratio [OR] = 6.7 and 6.9) and late GI and genitourinary adverse effects (OR = 0.1 and 0.2). The lower dose was chosen more often by the older patients, low-risk patients, patients without hormone treatment, and patients with a low anxiety or depression score.nnnCONCLUSIONnMost patients with localized prostate cancer prefer the lower radiation dose. Our findings indicate that many patients attach more weight to specific quality-of-life aspects (eg, GI toxicity) than to improving survival. Treatment preferences of patients with localized prostate cancer can and should be involved in radiotherapy decision making.

Doctors’ and Patients’ Preferences for Participation and Treatment in Curative Prostate Cancer Radiotherapy

PURPOSEnPhysicians hold opinions about unvoiced patient preferences, so-called substitute preferences. We studied whether doctors can predict preferences of patients supported with a decision aid.nnnMETHODSnA total of 150 patients with prostate cancer facing radiotherapy were included. After the initial consultation, without discussing any treatment choice, physicians gave substitute judgments for patients decision-making and radiation dose preferences. Physicians knew that several weeks later, patients would be empowered by a decision aid supporting a choice between two radiation doses involving a trade-off between disease-free survival and adverse effects. Subsequently, patient preferences for decision making (whether or not they wanted to choose a radiation dose) and for treatment (low or high dose) were obtained. The chosen radiation dose actually was administered.nnnRESULTSnOf the patients studied, 79% chose a treatment; physicians believed that 66% of the patients wanted to choose. Agreement was poor (64%; = 0.13; P = .11), and was better as patients became more hopeful (odds ratio [OR] = 4.4 per unit; P = .001) and as physicians experience increased (OR = 1.09 per year; P = .02). Twenty percent of physicians preferences, 51% of physicians substitute preferences, and 71% of patients preferences favored the lower dose; agreement was again poor (70%; = 0.2; P = .03).nnnCONCLUSIONnPhysicians had problems predicting the preferences of patients empowered with a decision aid. They slightly underestimated patients decision-making preferences, and underestimated patients preferences for the less toxic treatment. Counseling might be improved by first informing patients-possibly using a decision aid--before discussing patient preferences.

Decision Making Regarding Prophylactic Mastectomy: Stability of Preferences and the Impact of Anticipated Feelings of Regret

PURPOSEnWomen who test positive for a BRCA1/2 mutation face difficult choices to manage their breast cancer risk; one of these choices is whether to opt for prophylactic mastectomy. Few data are available about this decision-making process. The current study provides data regarding the stability of risk-management preferences over time and the factors that are associated with these preferences.nnnPATIENTS AND METHODSnWe analyzed data from 338 women who opted for breast cancer antigen (BRCA) testing. First, we prospectively assessed preferences of 80 BRCA mutation carriers at five different points in time ranging from 1 week after blood sampling up to 9 months after BRCA-test disclosure. Second, we applied univariate and multivariate regression analyses to examine which medical, sociodemographic, and psychological factors are related to a preference for prophylactic mastectomy.nnnRESULTSnNinety percent of the women already indicated a preference regarding risk management at baseline. Moreover, most women had stable preferences over time. Furthermore, anticipated feelings of regret in case of a hypothetical breast cancer diagnosis in the near future were strongly related to risk-management preference (odds ratio = 8.93; P < .0001).nnnCONCLUSIONnWomen seem to decide at a relatively early stage about their risk-management preferences. Many of them may be sensitive to the possibility of regret in case of a bad outcome. We discuss whether possible regret in the future is a rational reason for opting for prophylactic mastectomy, or whether it signifies an emotional coping process or strategy in which the future costs are no longer fully considered.

Inconsistencies in TTO and VAS values for EQ-5D health states.

Background. Most EQ-5D health states can be ordered logically. When people assign values to different health states, they may violate this logical order, which can be seen as inconsistencies. Objective. The aim of this study was to assess the effect of inconsistently valued EQ-5D health states on mean visual analog scale (VAS) and time trade-off (TTO) values. The authors also examined the effect of removing respondents with high numbers of inconsistent states on the estimation of tariffs, which is used to interpolate values to all possible EQ-5D states from the direct valuation of a subset of states. Method. Data from the Dutch EQ-5D valuation study were used. A representative sample of 309 Dutch adults valued 17 EQ-5D health states by VAS and TTO. A state was valued inconsistently when it had a higher value than at least 1 logically better state. Mean values of groups with various numbers of inconsistently valued states were compared. Results. Of the respondents, 65% had inconsistencies for VAS and 89% for TTO. The mean VAS values of consistent respondents tend to be lower. For TTO, those with inconsistencies gave lower values. Removing data of respondents with the highest number of inconsistently valued states for VAS (13%) and TTO (9%) did not result in statistically significant different coefficients in the estimated tariff using all data. Conclusion. The majority of respondents valued at least 1 state inconsistently. For both VAS and TTO, the presence of these inconsistencies did not affect the estimated tariffs

Proportional heuristics in time tradeoff and conjoint measurement

The time-tradeoff (TTO) test is widely used to measure quality of life for different health states. Subjects are asked to equate the value of living a given period in an inferior health state to the value of living a shorter period in good health. Applications of TTOs have been criticized based on the fact that the value of future life duration is taken as the future life duration itself. The authors show that for a health state in which a subject does not want to live longer than a specified amount of time, subjects responses do not comply with the assumption that the value of the period in inferior health is equated to the value of the shorter period in good health Actually, preference reversals with respect to such a health state point to the use of a proportional heuristic in the TTO test. Comparisons of the TTO test in these subjects with category scaling and difference measurements also favor a proportional inter pretation of the TTO test. In tests based on conjoint measurement, these subjects also appear to use a proportional heuristic. Consequences of the use of the TTO test and conjoint measurement m quality-of-life models are discussed Key words: utility assessment, QALY, conjoint measurement; preference reversals; compatibility effect. (Med Decis Making 1996;16:36-44)

The Discrepancy between Risky and Riskless Utilities A Matter of Framing

Utilities differ according to whether they are derived from risky (gamble) and riskless (visual analog scale, time-tradeoff) assessment methods. The discrepancies are usu ally explained by assuming that the utilities elicited by risky methods incorporate atti tudes towards risk, whereas riskless utilities do not. In (cumulative) prospect theory, risk attitude is conceived as consisting of two components: a decision-weight function (attentiveness to changes in, or sensitivity towards, chance) and a utility function (sen sitivity towards outcomes). The authors data suggest that a framing effect is a hitherto unrecognized and important factor in causing discrepancies between risky and riskless utilities. They collected risky evaluations with the gamble method, and riskless evalu ations with difference measurement. Risky utilities were derived using expected-utility theory and prospect theory. With the latter approach, sensitivity towards outcomes and sensitivity towards chance are modeled separately. When the hypothesis that risky utilities from prospect theory coincide with riskless utilities was tested, it was rejected (n = 8, F(1,7) = 132, p = 0.000), suggesting that a correction for sensitivity towards chance is not sufficient to resolve the difference between risky and riskless utilities. Next, it was assumed that different gain/loss frames are induced by risky and riskless elicitation methods. Indeed, identical utility functions were obtained when the gain/loss frames were made identical across methods (n = 7), suggesting that framing was operative. The results suggest that risky and riskless utilities are identical after correc tions for sensitivity towards chance and framing. Key words: utility assessment; de cision making; risk attitude; framing; risky and riskless utilities. (Med Decis Making 1999;19:435-447)

Assessment of the Time-tradeoff Val ues for Prophylactic Mastectomy of Women with a Suspected Genetic Predisposition to Breast Cancer

Background. Female carriers of the breast-cancer-susceptibility genes BRCA1 and BRCA2 are at high risk for breast cancer (85%). They face the choice between pro phylactic mastectomy (PM) and breast cancer screening. For this treatment choice, a shared-decision-making program was developed. In this program, the time tradeoff (TTO) was used to assess preferences for PM. Purpose. Assessment of the feasibility, constant proportional tradeoff, and reliability of using the TTO for this purpose. Meth ods. Fifty-four women suspected to carry the BRCA1/2 mutation were provided with comprehensive relevant information. Their preferences for PM were assessed on two occasions. Discrepancies between preferences indicated by the two tests were re solved by testing a third time. The preferences assessed on the last occasion were used for individual decision analyses. In order to test constant proportional tradeoff, the TTO consisted of four items with different numbers of life years. Results. Forty- two women (78%) completed the TTO twice and nine women (17%) performed the test a third time. Three women (5%) completed the TTO only once. The mean TTO value for PM at the last replication was 0.69 (SD = 0.30). Violations of constant pro portional tradeoff were significant: the largest tradeoffs were recorded for the shortest durations. Pearsons correlation coefficient between the TTO values for the two last sessions was 0.96. Conclusion. Assessment of individual preferences by the TTO in this patient group is feasible and reliable. Therefore, the TTO can be used in clinical settings to elicit treatment preferences of women proven or suspected to have a ge netic predisposition to breast cancer. Key words: shared decision making; breast can cer ; prophylactic mastectomy; preference assessment; time tradeoff; genetic predis position. (Med Decis Making 1998;18:268-277)

Preference reversals : Violations of unidimensional procedure invariance

textabstractPreference reversals have usually been explained by weighted additive models, in which different tasks give rise to different importance weights for the stimulus attributes, resulting in contradictory trade-offs. This article presents a preference reversal of a more extreme nature. Let (10, 5 Migr) denote living 10 years with a migraine for 5 days per week. Many participants preferred (10, 5 Migr) to (20, 5 Migr). However, when asked to equate these two options with a shorter period of good health, they usually demanded more healthy life years for (20, 5 Migr) than for (10, 5 Migr). This preference reversal within a single dimension cannot be explained by different importance weights and suggests irrationalities at a more fundamental level. Most participants did not change their responses after being confronted with their inconsistencies.

Evaluation of a Shared Decision Making Program for Women Suspected to Have a Genetic Predisposition to Breast Cancer Preliminary Results

Background. Women suspected to have a genetic predisposition to breast cancer face the difficult choice between regular breast cancer screening and prophylactic mastec tomy. The authors developed a shared decision making program (SDMP) to support this decision. Objectives. To evaluate the SDMP in terms of practicality, beneficial effects, and patient satisfaction. Design. A one-group pretest-posttest design was used. Measures. Decision uncertainty, decision burden, subjective knowledge, and risk comprehension were assessed before and after the SDMP. Additional measures were obtained for concepts related to breast cancer concern, desire to participate in the program, satisfaction, program acceptability, and emotional reaction to the program information. Results. Seventy-two women, most of whom were awaiting the genetic test results, participated. Decision uncertainty (effect size d = 0.37) and decision bur den (d= 0.41) were reduced by the SDMP. Subjective knowledge (averaged d= 0.94) and risk comprehension were improved. The women were satisfied with the SDMP and found its rationale acceptable. Women who had strong emotional reactions to the information benefited less from the SDMP, whereas women with strong desires to participate in the decision benefited more. Conclusions. There is a need to give pa tients more information, especially about prophylactic mastectomy and among gene carriers. Beneficial effects were observed irrespective of whether genetic status was known, suggesting that information concerning treatment options should be made available as soon as DNA testing begins. The better psychological outcomes of women with stronger desires to participate may arise because the desire to participate is char acteristic of emotional stability. Key words: shared decision making; breast cancer; genetic predisposition; patient participation; patient satisfaction. (Med Decis Making 1999; 19:230-241)

Prophylactic Mastectomy or Screening in Women Suspected to Have the BRCA1/2 Mutation A Prospective Pilot Study of Women's Treatment Choices and Medical and Decision-analytic Recommendations

Background. Women suspected to have the BRCA1/2 mutation may choose between two management options: breast cancer screening and prophylactic mastectomy (PM). Objectives. To compare womens treatment choices with medical and decision-analytic recommendations and to explore variables related to the womens choices. Methods. After provision of information, individual time-tradeoff values for the health outcome living after PM were assessed and incorporated into a decision-analytic model, which compared the management options PM and screening with respect to their effects on quality-adjusted life expectancy. Results. Of the 54 women suspected to have the mutation, 51 completed the shared-decision-making procedure. Quality-adjusted life expectancy after PM management was longer for 67% of proven carriers and for 58% of women awaiting the DNA-test result. Twelve proven carriers made definitive treatment choices: eight (67%) chose PM and four (33%) chose screening. All carriers treatment choices agreed with the normative decision-analytic recommendations. Four (33%) disagreed with the medical recommendations. Of the 36 women awaiting DNA-test results, 32 made hypothetical treatment choices. The agreement between these hypothetical treatment choices and the decision-analytic recommendations was good (78%). Combining data from all 48 women, being married (OR = 14.00, p = 0.006), having children (OR = 4.71, p = 0.02), low desire to participate (OR = 0.14, p = 0.004), high decisional stress (OR = 5.22, p = 0.01), a lower estimate of the probability of cure for screen-detected breast cancer (OR = 0.13, p = 0.004), and higher time-tradeoff values for PM (OR = 182, p < 0.0001) made a choice for PM more likely. Conclusions. The complete agreement between the decision-analytic recommendations and the carriers choices suggests that women act in accordance with normative decision theory. The disagreement between the carriers choices and the medical recommendations suggests that womens choices and physicians recommendations were guided by different arguments. The strong association between time-tradeoff value and treatment choice suggests that the time-tradeoff is a valid method to assess preferences. Key words: breast cancer; prophylactic mastectomy; screening; shared decision making, utilities; time preferences. (Med Decis Making 2000;20:251-262)