Assessment of the time-tradeoff values for prophylactic mastectomy of women with a suspected genetic predisposition to breast cancer

Decision aids for female BRCA mutation carriers: a scoping review

OBJECTIVES

Women who inherit a pathogenic BRCA1 or BRCA2 mutation are at substantially higher risk of developing breast and ovarian cancer than average. Several cancer risk management strategies exist to address this increased risk. Decisions about which strategies to choose are complex, personal and multifactorial for these women. Decision aids (DAs) are tools that assist patients in making health-related decisions. The aim of this scoping review was to map evidence relating to the development and testing of patient DAs for cancer unaffected BRCA mutation carriers.

DESIGN

Scoping review conducted according to the Joanna Briggs Institute's (JBI's) scoping review methodological framework.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, Web of Science. No restrictions applied for language or publication date. A manual search was also performed.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies on DAs for cancer risk management designed for or applicable to women with a pathogenic BRCA1 or BRCA2 mutation who are unaffected by breast or ovarian cancer.

DATA EXTRACTION AND SYNTHESIS

Data were extracted using a form based on the JBI instrument for extracting details of studies' characteristics and results. Data extraction was performed independently by two reviewers. Extracted data were tabulated.

RESULTS

32 evidence sources relating to development or testing of 21 DAs were included. Four DAs were developed exclusively for cancer unaffected BRCA mutation carriers. Of these, two covered all guideline recommended risk management strategies for this population though only one of these was readily available publicly in its full version. All studies investigating DA effectiveness reported a positive effect of the DA under investigation on at least one of the outcomes evaluated, however only six DAs were tested in randomised controlled trials.

CONCLUSION

This scoping review has mapped the landscape of the literature relating to developing and testing, DAs applicable to cancer unaffected BRCA mutation carriers.

Data on Utility in Cost-Utility Analyses of Genetic Screen-and-Treat Strategies for Breast and Ovarian Cancer

Simple Summary

The prevention of hereditary breast and ovarian cancer involves genetic counselling and several highly preference-sensitive alternatives (i.e., risk-reducing surgeries). In health economics models, data on health preferences applied (i.e., utility values) are heterogeneous. In this methodological analysis, we compared the application of utility values among cost–utility models of targeted genetic testing for the prevention of breast and ovarian cancer. While varying utilities on risk-reducing surgeries and cancer states did not impact the cost–utility ratio, utility losses/gains due to a positive/negative test may strongly affect the cost–utility ratio and should be considered mandatory in future models. Because women’s health preferences may have changed as a result of improved oncologic care and genetic counselling, studies for ascertaining women’s health preferences should be updated.

Abstract

Genetic screen-and-treat strategies for the risk-reduction of breast cancer (BC) and ovarian cancer (OC) are often evaluated by cost–utility analyses (CUAs). This analysis compares data on health preferences (i.e., utility values) in CUAs of targeted genetic testing for BC and OC. Based on utilities applied in fourteen CUAs, data on utility including related assumptions were extracted for the health states: (i) genetic test, (ii) risk-reducing surgeries, (iii) BC/OC and (iv) post cancer. In addition, information about the sources of utility and the impact on the cost-effectiveness was extracted. Utility for CUAs relied on heterogeneous data and assumptions for all health states. The utility values ranged from 0.68 to 0.97 for risk-reducing surgeries, 0.6 to 0.85 for BC and 0.5 to 0.82 for OC. In two out of nine studies, considering the impact of the test result strongly affected the cost–effectiveness ratio. While in general utilities seem not to affect the cost–utility ratio, in future modeling studies the impact of a positive/negative test on utility should be considered mandatory. Women’s health preferences, which may have changed as a result of improved oncologic care and genetic counselling, should be re-evaluated.

Risk-reducing mastectomy for the prevention of primary breast cancer

BACKGROUND

Recent progress in understanding the genetic basis of breast cancer and widely publicized reports of celebrities undergoing risk-reducing mastectomy (RRM) have increased interest in RRM as a method of preventing breast cancer. This is an update of a Cochrane Review first published in 2004 and previously updated in 2006 and 2010.

OBJECTIVES

(i) To determine whether risk-reducing mastectomy reduces death rates from any cause in women who have never had breast cancer and in women who have a history of breast cancer in one breast, and (ii) to examine the effect of risk-reducing mastectomy on other endpoints, including breast cancer incidence, breast cancer mortality, disease-free survival, physical morbidity, and psychosocial outcomes.

SEARCH METHODS

For this Review update, we searched Cochrane Breast Cancer's Specialized Register, MEDLINE, Embase and the WHO International Clinical Trials Registry Platform (ICTRP) on 9 July 2016. We included studies in English.

SELECTION CRITERIA

Participants included women at risk for breast cancer in at least one breast. Interventions included all types of mastectomy performed for the purpose of preventing breast cancer.

DATA COLLECTION AND ANALYSIS

At least two review authors independently abstracted data from each report. We summarized data descriptively; quantitative meta-analysis was not feasible due to heterogeneity of study designs and insufficient reporting. We analyzed data separately for bilateral risk-reducing mastectomy (BRRM) and contralateral risk-reducing mastectomy (CRRM). Four review authors assessed the methodological quality to determine whether or not the methods used sufficiently minimized selection bias, performance bias, detection bias, and attrition bias.

MAIN RESULTS

All 61 included studies were observational studies with some methodological limitations; randomized trials were absent. The studies presented data on 15,077 women with a wide range of risk factors for breast cancer, who underwent RRM.Twenty-one BRRM studies looking at the incidence of breast cancer or disease-specific mortality, or both, reported reductions after BRRM, particularly for those women with BRCA1/2 mutations. Twenty-six CRRM studies consistently reported reductions in incidence of contralateral breast cancer but were inconsistent about improvements in disease-specific survival. Seven studies attempted to control for multiple differences between intervention groups and showed no overall survival advantage for CRRM. Another study showed significantly improved survival following CRRM, but after adjusting for bilateral risk-reducing salpingo-oophorectomy (BRRSO), the CRRM effect on all-cause mortality was no longer significant.Twenty studies assessed psychosocial measures; most reported high levels of satisfaction with the decision to have RRM but greater variation in satisfaction with cosmetic results. Worry over breast cancer was significantly reduced after BRRM when compared both to baseline worry levels and to the groups who opted for surveillance rather than BRRM, but there was diminished satisfaction with body image and sexual feelings.Seventeen case series reporting on adverse events from RRM with or without reconstruction reported rates of unanticipated reoperations from 4% in those without reconstruction to 64% in participants with reconstruction.In women who have had cancer in one breast, removing the other breast may reduce the incidence of cancer in that other breast, but there is insufficient evidence that this improves survival because of the continuing risk of recurrence or metastases from the original cancer. Additionally, thought should be given to other options to reduce breast cancer risk, such as BRRSO and chemoprevention, when considering RRM.

AUTHORS' CONCLUSIONS

While published observational studies demonstrated that BRRM was effective in reducing both the incidence of, and death from, breast cancer, more rigorous prospective studies are suggested. BRRM should be considered only among those at high risk of disease, for example, BRCA1/2 carriers. CRRM was shown to reduce the incidence of contralateral breast cancer, but there is insufficient evidence that CRRM improves survival, and studies that control for multiple confounding variables are recommended. It is possible that selection bias in terms of healthier, younger women being recommended for or choosing CRRM produces better overall survival numbers for CRRM. Given the number of women who may be over-treated with BRRM/CRRM, it is critical that women and clinicians understand the true risk for each individual woman before considering surgery. Additionally, thought should be given to other options to reduce breast cancer risk, such as BRRSO and chemoprevention when considering RRM.

A Systematic Review of the Techniques Used to Value Temporary Health States

BACKGROUND

A broad literature on health state utility values exists, but compared with chronic health states (HSs), issues surrounding the valuation of temporary health states (THSs) have been poorly explored.

OBJECTIVES

To assess the methods used by previous studies to value HSs that are considered temporary so as to determine the strengths and limitations associated with various approaches and to inform future study designs.

METHODS

A systematic review was undertaken to explore the methods used, assess how the valuation was conducted for diseases that might lead to HSs deemed as temporary, and identify the challenges encountered in the valuation of THSs.

RESULTS

Of the 36 relevant studies, 22 were explicit that the HS being valued was temporary. Most of the studies used more than one technique (often incorporating both conventional and adapted approaches). In using adapted techniques, the primary challenge was identifying an appropriate intermediate "anchor" HS and the possibility of negative utilities.

CONCLUSIONS

There is no agreement on the most methodologically robust approach to THS valuation. Valuation is complex and important issues relating to the validity, practicality, and reliability of the techniques used were not adequately covered by most of the studies identified.

The QALY Model and Individual Preferences for Health States and Health Profiles over Time: A Systematic Review of the Literature

The numbers of quality-adjusted life years (QALYs) gained are increasingly being used to represent the gains in individual utility from treatment. This requires that the value of a health improvement to an individual is a simple product of gains in quality of life and length of life. The article reports on a systematic review of the literature on 2 issues: whether the value of a state is affected by how long the state lasts, and by states that come before or after it. It was found that individual preferences over health are influenced by the duration of health states and their sequence. However, although there is much variation across individual respondents, the assumptions tend to hold much better when valuations are aggregated across respondents, which is encouraging for economic evaluations that rely on using average (mean or median) values.

Time trade-off: one methodology, different methods

There is no scientific consensus on the optimal specification of the time trade-off (TTO) task. As a consequence, studies using TTO to value health states may share the core element of trading length of life for quality of life, but can differ considerably on many other elements. While this pluriformity in specifications advances the understanding of TTO from a methodological point of view, it also results in incomparable health state values. Health state values are applied in health technology assessments, and in that context comparability of information is desired. In this article, we discuss several alternative specifications of TTO presented in the literature. The defining elements of these specifications are identified as being either methodological, procedural or analytical in nature. Where possible, it is indicated how these elements affect health state values (i.e., upward or downward). Finally, a checklist for TTO studies is presented, which incorporates a list of choices to be made by researchers who wish to perform a TTO task. Such a checklist enables other researchers to align methodologies in order to enhance the comparability of health state values.

Lead time TTO: leading to better health state valuations?

Preference elicitation tasks for better than dead (BTD) and worse than dead (WTD) health states vary in the conventional time trade-off (TTO) procedure, casting doubt on uniformity of scale. 'Lead time TTO' (LT-TTO) was recently introduced to overcome the problem. We tested different specifications of LT-TTO in comparison with TTO in a within-subject design. We elicited preferences for six health states and employed an intertemporal ranking task as a benchmark to test the validity of the two methods. We also tested constant proportional trade-offs (CPTO), while correcting for discounting, and the effect of extending the lead time if a health state is considered substantially WTD. LT-TTO produced lower values for BTD states and higher values for WTD states. The validity of CPTO varied across tasks, but it was higher for LT-TTO than for TTO. Results indicate that the ratio of lead time to disease time has a greater impact on results than the total duration of the time frame. The intertemporal ranking task could not discriminate between TTO and LT-TTO.

A test of independence of discounting from quality of life

The quality-adjusted life-years (QALY) model assumes quality and quantity of life can be multiplied into a single index and requires quality and quantity to be mutually independent, which need not hold empirically. This paper proposes a new test for measuring independence of utility of life duration from quality of life in a riskless setting. We use a large representative sample of Dutch citizens and include two health states generally considered better than dead (BTD) and one health state considered worse than dead (WTD). Independence cannot be rejected when comparing the BTD health states, but is rejected when comparing the BTD states with the WTD state. In particular, utility of life duration becomes more concave for the WTD state. This may suggest that independence holds only for BTD health states. This has implications for the QALY model and would require using sign-dependent utility of life duration functions.

Constantly proving the opposite? A test of CPTO using a broad time horizon and correcting for discounting

Purpose

An important assumption underlying the quality-adjusted life year (QALY) model is that people trade off life years against health in the same proportion irrespective of the number of remaining life years. This is known as the constant proportional trade-offs (CPTO) condition. Previous studies have produced mixed empirical evidence about the validity of CPTO. This paper is the first to test CPTO using the time trade-off (TTO) method for a broad time horizon.

Methods

In a sample of 83 students, we use a choice based TTO protocol to elicit TTO scores for back pain, using ten different gauge durations ranging between 1 and 46 years. The TTO scores are corrected for discounting, which is elicited by means of the direct method.

Results

We find average TTO scores varying between 0.72 and 0.81. Although the scores do not differ much for different durations in absolute terms, some differences are significant, rejecting CPTO, with and without correcting for discounting. No clear relationship between TTO scores and gauge duration is found. An anchoring and rounding heuristic to some extent explains our results.

Conclusions

Our findings highlight the importance of elicitation methods and context dependencies in QALY measurement and warrant detailed investigation of their influence.

Prophylactic mastectomy for the prevention of breast cancer

BACKGROUND

Recent progress in understanding the genetic basis of breast cancer has increased interest in prophylactic mastectomy (PM) as a method of preventing breast cancer.

OBJECTIVES

(i) To determine whether prophylactic mastectomy reduces death rates from any cause in women who have never had breast cancer and in women who have a history of breast cancer in one breast, and (ii) to examine the effect of prophylactic mastectomy on other endpoints, including breast cancer incidence, breast cancer mortality, disease-free survival, physical morbidity, and psychosocial outcomes.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, 2002), MEDLINE and Cancerlit (1966 to June 2006), EMBASE (1974 to June 2006), and the WHO International Clinical Trials Registry Platform (WHO ICTRP) search portal (until June 2006). Studies in English were included.

SELECTION CRITERIA

Participants included women at risk for breast cancer in at least one breast. Interventions included all types of mastectomy performed for the purpose of preventing breast cancer.

DATA COLLECTION AND ANALYSIS

At least two authors independently abstracted data. Data were summarized descriptively; quantitative meta-analysis was not feasible due to heterogeneity of study designs and insufficient reporting. Data were analyzed separately for bilateral prophylactic mastectomy (BPM) and contralateral prophylactic mastectomy (CPM).

MAIN RESULTS

All 39 included studies were observational studies with some methodological limitations; randomized trials were absent. The studies presented data on 7,384 women with a wide range of risk factors for breast cancer who underwent PM.BPM studies on the incidence of breast cancer and/or disease-specific mortality reported reductions after BPM particularly for those with BRCA1/2 mutations. For CPM, studies consistently reported reductions in incidence of contralateral breast cancer but were inconsistent about improvements in disease-specific survival. Only one study attempted to control for multiple differences between intervention groups and this study showed no overall survival advantage for CPM at 15 years. Another study showed significantly improved survival following CPM but after adjusting for bilateral prophylactic oophorectomy, the CPM effect on all-cause mortality was no longer significant.Sixteen studies assessed psychosocial measures; most reported high levels of satisfaction with the decision to have PM but more variable satisfaction with cosmetic results. Worry over breast cancer was significantly reduced after BPM when compared both to baseline worry levels and to the groups who opted for surveillance rather than BPM.Case series reporting on adverse events from PM with or without reconstruction reported rates of unanticipated re-operations from 4% in those without reconstruction to 49% in patients with reconstruction.

AUTHORS' CONCLUSIONS

Sixteen studies have been published since the last version of the review, without altering our conclusions. While published observational studies demonstrated that BPM was effective in reducing both the incidence of, and death from, breast cancer, more rigorous prospective studies (ideally randomized trials) are needed. BPM should be considered only among those at very high risk of disease. There is insufficient evidence that CPM improves survival and studies that control for multiple confounding variables are needed.

On the (not so) constant proportional trade-off in TTO

Purpose

The linear and power QALY models require that people in Time Trade-off (TTO) exercises sacrifice the same proportion of lifetime to obtain a health improvement, irrespective of the absolute amount. However, evidence on these constant proportional trade-offs (CPTOs) is mixed, indicating that these versions of the QALY model do not represent preferences. Still, it may be the case that a more general version of the QALY model represents preferences. This version has the property that people want to sacrifice the same proportion of utilities of lifetime for a health improvement, irrespective of the amount of this lifetime.

Methods

We use a new method to correct TTO scores for utility of life duration and test whether decision makers trade off utility of duration and quality at the same rate irrespective of duration.

Results

We find a robust violation of CPTO for both uncorrected and corrected TTO scores. Remarkably, we find higher values for longer durations, contrary to most previous studies. This represents the only study correcting for utility of life duration to find such a violation.

Conclusions

It seems that the trade-off of life years is indeed not so constantly proportional and, therefore, that health state valuations depend on durations.

International comparisons in valuing EQ-5D health states: a review and analysis

OBJECTIVE

To identify the key methodological issues in the construction of population-level EuroQol 5-dimensions (EQ-5D)/time trade-off (TTO) preference elicitation studies.

METHOD

This study involved three components. The first was to identify existing population-level EQ-5D TTO studies. The second was to illustrate and discuss the key areas of divergence between studies, including the international comparison of tariffs. The third was to portray the relative merits of each of the approaches and to compare the results of studies across countries.

RESULTS

While most articles report use of the protocol developed in the original UK study, we identified three key areas of divergence in the construction and analysis of surveys. These are the number of health states valued to determine the algorithm for estimating all health states, the approach to valuing states worse than immediate death, and the choice of algorithm. The evidence on international comparisons suggests differences between countries although it is difficult to disentangle differences in cultural attitudes with random error and differences as a result of methodological divergence.

CONCLUSIONS

Differences in methods may obscure true differences in values between countries. Nevertheless, population-specific valuation sets for countries engaging in economic evaluation would better reflect cultural differences and are therefore more likely to accurately represent societal attitudes.

A systematic review of information in decision aids

OBJECTIVE

We completed a systematic review of information reported as included in decision aids (DAs) for adult patients, to determine if it is complete, balanced and accurate.

SEARCH STRATEGY

DAs were identified using the Cochrane Database of DAs and searches of four electronic databases using the terms: 'decision aid'; shared decision making' and 'patients'; 'multimedia or leaflets or pamphlets or videos and patients and decision making'. Additionally, publications reporting DA development and actual DAs that were reported as publicly available on the Internet were consulted. Publications were included up to May 2006.

DATA EXTRACTION

Data were extracted on the following variables: external groups consulted in development of the DA, type of study used, categories of information, inclusion of probabilities, use of citation lists and inclusion of patient experiences.

MAIN RESULTS

68 treatment DAs and 30 screening DAs were identified. 17% of treatment DAs and 47% of screening DAs did not report any external consultation and, of those that did, DA producers tended to rely more heavily on medical experts than on patients' guidance. Content evaluations showed that (i) treatment DAs frequently omit describing the procedure(s) involved in treatment options and (ii) screening DAs frequently focus on false positives but not false negatives. About 1/2 treatment DAs reported probabilities with a greater emphasis on potential benefits than harms. Similarly, screening DAs were more likely to provide false-positive than false-negative rates.

CONCLUSIONS

The review led us to be concerned about completeness, balance and accuracy of information included in DAs.

A comparison of 3 valuation methods for temporary health states in patients treated with oral anticoagulants

BACKGROUND

The application of the time tradeoff (TTO) method in temporary health states may lead to less valid results because an unrealistic scenario is presented to patients. The chained TTO has been proposed to solve this problem.

OBJECTIVES

To compare a chained TTO method with a conventional TTO method in the valuation of temporary health states, in terms of consistency and reliability. To compare both TTO methods with direct rating.

PATIENTS AND METHODS

Eighty-four patients treated with oral anticoagulants were interviewed twice. During the 1st interview, values for 5 temporary health states were obtained with a rank ordering procedure, direct rating, and the chained TTO method. During the 2nd interview, either the 1st interview was repeated (n = 30) or health state values were obtained with the conventional TTO method (n = 54). Consistency was assessed by comparing the 3 valuation methods with the rank ordering procedure. Generalizability theory was used to assess reliability.

RESULTS

The 3 methods produced significantly different valuations of health states. Chained TTO values were higher than values obtained with direct rating and the conventional TTO. Consistency and reliability did not differ across the 3 methods.

CONCLUSION

The authors found no evidence for a difference in consistency and reliability between the chained TTO method and the conventional TTO method in the valuation of temporary health states. As direct rating is simpler to administer than both TTO methods, one could consider using direct ratings for the valuation of temporary health states. Biases associated with the conventional and the chained TTO method are discussed.

Prophylactic mastectomy for the prevention of breast cancer

BACKGROUND

Breast cancer is the most common cancer and the second most common cause of cancer-related death among North American and Western European women. Recent progress in understanding the genetic basis of breast cancer, along with rising incidence rates, have resulted in increased interest in prophylactic mastectomy as a method of preventing breast cancer, particularly in those with familial susceptibility.

OBJECTIVES

The primary objective was to determine whether prophylactic mastectomy reduces death from any cause in women who have never had breast cancer and in women who have a history of breast cancer in one breast. The secondary objective was to examine the effect of prophylactic mastectomy on other endpoints including breast cancer incidence, breast cancer mortality, disease-free survival, physical morbidity, and psychosocial outcomes.

SEARCH STRATEGY

Electronic searches were performed in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Cancerlit, and the Science Citation Index.

SELECTION CRITERIA

Inclusion criteria were studies in English of any design type including randomized or nonrandomized controlled trials, cohort studies, case-control studies, and case series with at least ten participants. Participants included women at risk for breast cancer in at least one breast. Interventions included all types of mastectomy performed for the purpose of preventing breast cancer, including subcutaneous mastectomy, total or simple mastectomy, modified radical mastectomy, and radical mastectomy.

DATA COLLECTION AND ANALYSIS

Information on patients, interventions, methods, and results were extracted by at least two independent reviewers. Methodological quality was assessed based on how well each study minimized potential selection bias, performance bias, detection bias, and attrition bias. Data for each study were summarized descriptively; quantitative meta-analysis was not feasible due to heterogeneity of study designs and insufficient reporting. Data were analyzed separately for bilateral prophylactic mastectomy (BPM) and contralateral prophylactic mastectomy (CPM).

MAIN RESULTS

Twenty-three studies, including more than 4,000 patients, met inclusion criteria. No randomized or nonrandomized controlled trials were found. Most studies were either case series or cohort studies. All studies had methodological limitations, with the most common source of potential bias being systematic differences between the intervention and comparison groups that could potentially be associated with a particular outcome. Thirteen studies assessed the effectiveness of BPM. No study assessed all-cause mortality after BPM. All studies reporting on incidence of breast cancer and disease-specific mortality reported reductions after BPM. Nine studies assessed psychosocial measures; most reported high levels of satisfaction with the decision to have prophylactic mastectomy (PM) but more variable satisfaction with cosmetic results. Only one study assessed satisfaction with the psychological support provided by healthcare personnel during risk counseling and showed that more women were dissatisfied than satisfied with the support they received in the healthcare setting. Worry over breast cancer was significantly reduced after BPM when compared both to baseline worry levels and to the groups who opted for surveillance rather than BPM. Three studies reported body image/feelings of femininity outcomes, and all reported that a substantial minority (about 20%) reported BPM had adverse effects on those domains. Six studies assessed contralateral prophylactic mastectomy. Studies consistently reported reductions in contralateral incidence of breast cancer but were inconsistent about improvements in disease-specific survival. Only one study attempted to control for multiple differences between intervention groups, and this study showed no overall survival advantage for CPM at 15 years. Two case series were exclusively focused on adverse events from prophylactic mastectomy with reconstruction, and both reported rates of unanticipated re-operations from 30% to 49%.

REVIEWERS' CONCLUSIONS

While published observational studies demonstrated that BPM was effective in reducing both the incidence of, and death from, breast cancer, more rigorous prospective studies (ideally randomized trials) are needed. The studies need to be of sufficient duration and make better attempts to control for selection biases to arrive at better estimates of risk reduction. The state of the science is far from exact in predicting who will get or who will die from breast cancer. By one estimate, most of the women deemed high risk by family history (but not necessarily BRCA 1 or 2 mutation carriers) who underwent these procedures would not have died from breast cancer, even without prophylactic surgery. Therefore, women need to understand that this procedure should be considered only among those at very high risk of the disease. For women who had already been diagnosed with a primary tumor, the data were particularly lacking for indications for contralateral prophylactic mastectomy. While it appeared that contralateral mastectomy may reduce the incidence of cancer in the contralateral breast, there was insufficient evidence about whether, and for whom, CPM actually improved survival. Physical morbidity is not uncommon following PM, and many women underwent unanticipated re-operations (usually due to problems with reconstruction); however, these data need to be updated to reflect changes in surgical procedures and reconstruction. Regarding psychosocial outcomes, women generally reported satisfaction with their decisions to have PM but reported satisfaction less consistently for cosmetic outcomes, with diminished satisfaction often due to surgical complications. Therefore, physical morbidity and post-operative surgical complications were areas that should be considered when deciding about PM. With regard to emotional well-being, most women recovered well postoperatively, reporting reduced cancer worry and showing reduced psychological morbidity from their baseline measures; exceptions also have been noted. Of the psychosocial outcomes measured, body image and feelings of femininity were the most adversely affected.

Randomized trial of a shared decision-making intervention consisting of trade-offs and individualized treatment information for BRCA1/2 mutation carriers

PURPOSE

To evaluate a shared decision-making intervention (SDMI) for BRCA1/2 mutation carriers who have to make a choice between screening and prophylactic surgery for breasts and/or ovaries.

PATIENTS AND METHODS

The SDMI consisted of two value assessment sessions, using the time trade-off method, followed by individualized treatment information based on (quality-adjusted) life expectancy. After the baseline assessment (2 weeks after a positive DNA test result), women were randomly assigned to the SDMI group (n = 44), receiving the SDMI 2 months after the test result, or to the control group (n = 44). The short- and long-term effects, 3 and 9 months after the test result, were assessed using questionnaires. Data were collected on well-being, treatment choice, and decision-related outcomes.

RESULTS

In the short term, the SDMI had no effect. In the long term, with respect to well-being, patients in the SDMI group had less intrusive thoughts (P =.05) and better general health (P =.01) and tended to be less depressed (P =.07). With respect to decision-related outcomes for the breasts, the SDMI group held stronger preferences (P =.02) and agreed more strongly to having weighed the pros and cons (P =.01). No effect was found on treatment choice. In the long term, interaction effects between the SDMI and cancer history were found. The SDMI showed an overall beneficial effect for unaffected women, whereas affected women tended to experience detrimental effects.

CONCLUSION

We conclude that the SDMI improved decision making in unaffected BRCA1/2 mutation carriers. Supporting decision making in a systematic way using trade-offs is beneficial for these women.

Eliciting women's preferences in health care: a review of the literature

OBJECTIVES

The increasing availability of information about health care suggests an expanding role for consumers to exercise their preferences in health-care decision-making. Numerous methods are available to assess consumer preferences in health care. We conducted a systematic review to characterize the study of women's preferences about health care.

METHODS

A MEDLINE search from 1965 to July 1999 was conducted as well as hand searches of the Medical Decision Making Journal (1981-1999) and references from retrieved articles. Only original articles on women's health issues were selected. Information on thirty-one variables related to study characteristics and preferences were extracted by two independent investigators. A third investigator resolved disagreements. Qualitative and quantitative analyses were conducted to synthesize the data.

RESULTS

Four hundred eighty-three studies were identified in the initial search. Seventy articles were selected for review based on title, abstract, and inclusion criteria. There was an increase in published articles and number of methods used to elicit preferences. White women were studied more than black women (p < .001). Preferences were mainly studied in outpatient settings (p < .005) and in the United States, United Kingdom, and Canada (83 percent). Preferences related to participation in decision-making were the most common (21 percent). Only 4 percent of the studies were performed to inform the debate for public policy questions. Willingness to pay was the method most used (11 percent), followed by category scaling (10 percent), rating scale (9 percent), standard-gamble (6 percent). Preferences for individual particular (opposed to sequential and health states) outcomes (68 percent), different treatments/tests (47 percent), and related to a treatment episode (31 percent) were addressed. Information regarding diseases, conditions, or procedures was given in 57 percent of studies. Information provided was mainly written (37 percent) and included positive and negative potential outcomes (67 percent). There is no relationship between the method or tool used for delivery information and the choice performed.

CONCLUSIONS

The literature on preferences in women's health care is limited to a fairly homogeneous population (white women from the United States, United Kingdom, and Canada). Additionally, use of utility-based measures to capture preferences has decreased over time while others methods (e.g., time trade-off [TTO], contingent valuation) have increased. Women's preferences are not necessarily uniform even when asked similar questions using similar tools. Little information on women's preferences exists to inform policy-makers about women's health care.

Assessment of health state utilities and quality of life in patients with malignant esophageal Dysphagia

OBJECTIVES

Palliation of terminal conditions such as malignant dysphagia must take into account individual preferences for aggressive or nonaggressive care, with a focus on quality of life. Despite this, there are very few data on patients' preferences for palliative therapy. This study is designed to quantitatively determine individual preferences for palliation of malignant dysphagia using health state utilities (HSU).

METHODS

HSU were measured using three methods: time trade-off (TTO), visual analog scale (VAS), and the EQ-5D. Patients with esophageal cancer were asked to rate their own state of health and of three standardized scenarios of local, regional, and metastatic disease.

RESULTS

Fifty patients with esophageal cancer were enrolled. Using the TTO method, the utilities of their own health state were 0.80 (95% CI 0.59-0.99) for localized, 0.54 (0.37-0.70) for regional, and 0.52 (0.32-0.71) for metastatic cancer showing no significant difference in mean utility scores for the three staging groups. VAS and EQ5D gave statistically similar values to TTO. Patients consistently rated their own utility better than the utility of standardized scenarios with similar stage and prognosis. Independent of their staging, patients with high dysphagia scores rated their utility worse than patients with low dysphagia scores.

CONCLUSIONS

These results confirm the perceived poor state of health of patients with esophageal cancer and are substantially lower than previous estimates in operated patients. Cost-effectiveness models must take into account significant differences between patients' assessment of their own state of health, and that of a "societal" perspective of others with a similar disease. All three methods provided similar estimates. Given the ease of use of VAS and EQ-5D, these methods may be preferable to TTO.

Palliative chemotherapy or best supportive care? A prospective study explaining patients' treatment preference and choice

In palliative cancer treatment, the choice between palliative chemotherapy and best supportive care may be difficult. In the decision-making process, giving information as well as patients' values and preferences become important issues. Patients, however, may have a treatment preference before they even meet their medical oncologist. An insight into the patient's decision-making process can support clinicians having to inform their patients. Patients (n=207) with metastatic cancer, aged 18 years or older, able to speak Dutch, for whom palliative chemotherapy was a treatment option, were eligible for the study. We assessed the following before they consulted their medical oncologist: (1) socio-demographic characteristics, (2) disease-related variables, (3) quality-of-life indices, (4) attitudes and (5) preferences for treatment, information and participation in decision-making. The actual treatment decision, assessed after it had been made, was the main study outcome. Of 207 eligible patients, 140 patients (68%) participated in the study. At baseline, 68% preferred to undergo chemotherapy rather than wait watchfully. Eventually, 78% chose chemotherapy. Treatment preference (odds ratio (OR)=10.3, confidence interval (CI) 2.8-38.0) and a deferring style of decision-making (OR=4.9, CI 1.4-17.2) best predicted the actual treatment choice. Treatment preference (total explained variance=38.2%) was predicted, in turn, by patients' striving for length of life (29.5%), less striving for quality of life (6.1%) and experienced control over the cause of disease (2.6%). Patients' actual treatment choice was most strongly predicted by their preconsultation treatment preference. Since treatment preference is positively explained by striving for length of life, and negatively by striving for quality of life, it is questionable whether the purpose of palliative treatment is made clear. This, paradoxically, emphasises the need for further attention to the process of information giving and shared decision-making.

The validity of time trade-off values in calculating QALYs: constant proportional time trade-off versus the proportional heuristic

In order to calculate quality adjusted life years (QALYs) from time trade-off (TTO) responses, individual preferences are required to satisfy the constant proportional time trade-off (CPTTO) assumption. Respondents who use a simple proportional heuristic may appear to satisfy CPTTO but will in fact generate preference reversals for states that are associated with a maximal endurable time (MET). Using data from 91 respondents, the study reported here examines the extent to which valuations satisfy the CPTTO assumption and the extent to which they might be generated by the proportional heuristic. The results suggest that respondents are using a proportional heuristic that casts doubt on the validity of using the TTO method to calculate QALYs for health states that are associated with MET preferences.

Patient preferences for treatment of lupus nephritis

OBJECTIVE

To examine the amount of improvement in renal survival that lupus patients require before choosing cyclophosphamide over azathioprine for the treatment of lupus nephritis.

METHODS

Patients were presented with descriptions of cyclophosphamide and azathioprine and asked to indicate their preferred choice if each conferred an equal probability of renal survival. Strength of preference was assessed by systematically increasing the probability of renal survival of the more toxic treatment until the respondent's choice switched.

RESULTS

Ninety-three well-educated women (mean age +/- SD 40 +/- 7 years) participated in the study. Ninety-eight percent (91/93) of the participants chose azathioprine over cyclophosphamide when both drugs conferred an equal probability of renal survival. Although most subjects switched preferences to cyclophosphamide for better renal survival, 31% (28/91) were unwilling to switch from azathioprine to cyclophosphamide for improved short-term renal survival, and 15% (14/91) were unwilling to switch from azathioprine to cyclophosphamide for improved long-term renal survival.

CONCLUSION

Although the majority of patients switched preferences to cyclophosphamide for better renal survival, a substantial minority was unwilling to accept the toxicity associated with cyclophosphamide, even if it was much better than azathioprine at preventing renal failure.

Measuring women's preferences for breast cancer treatments and BRCA1/BRCA2 testing

In establishing decision models in the treatment and prevention of breast cancer, it is important to evaluate patients' preferences for such interventions. The objectives of the present study were: (i) to characterize women's preferences for breast cancer treatments and BRCA1/BRCA2 testing, using the rating scale and standard gamble techniques; and (ii) to identify factors associated with these quality of life indices. Data were collected from women with breast cancer (n = 60), high-risk relatives of women with breast cancer (n = 58), and women in the general population (n = 51). Regardless of group membership, participants favoured treatment and prevention options that involved minimal physical invasiveness. Women with breast cancer rated lumpectomy and radiation treatment more highly than high-risk relatives and women in the general population. Preferences did not differ according to participants' intentions to undergo BRCA testing. Age was the only demographic variable associated with health state preferences. These findings hold implications for the application of patient preferences to clinical decision making.

Choice-matching preference reversals in health outcome assessments

BACKGROUND

Health outcome utility assessments generally assume procedural invariance. Preference reversals violating procedural invariance occur in economic scenarios when the assessment process shifts from a choice to a fill-in-the-blank task.

PURPOSE

To determine if similar reversals occur in utility assessments.

METHODS

One hundred thirty-six volunteer subjects completed 6 preference assessments of 4 personal health scenarios. Patients responded to otherwise identical tasks using either choice or fill-in-the-blank processes in a randomized crossover design. The authors determined the percentage of subjects preferring, or inferred to prefer, a given choice.

RESULTS

Preference reversals occurred in all assessment scenarios.

CONCLUSIONS

These preference reversals are a potential source of confusion for utility assessment and informed consent. They could be manipulated to achieve ends other than the best interest of patients. Anchoring or the prominence hypothesis may explain these findings.

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 women's treatment choices with medical and decision-analytic recommendations and to explore variables related to the women's 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 women's 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.

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 mastectomy. 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 burden (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 patients 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 characteristic of emotional stability.