Analysing public preferences for cancer screening programmes

Patient Preferences in Diagnostic Imaging: A Scoping Review

BACKGROUND

As new diagnostic imaging technologies are adopted, decisions surrounding diagnostic imaging become increasingly complex. As such, understanding patient preferences in imaging decision making is imperative.

OBJECTIVES

We aimed to review quantitative patient preference studies in imaging-related decision making, including characteristics of the literature and the quality of the evidence.

METHODS

The Pubmed, Embase, EconLit, and CINAHL databases were searched to identify studies involving diagnostic imaging and quantitative patient preference measures from January 2000 to June 2022. Study characteristics that were extracted included the preference elicitation method, disease focus, and sample size. We employed the PREFS (Purpose, Respondents, Explanation, Findings, Significance) checklist as our quality assessment tool.

RESULTS

A total of 54 articles were included. The following methods were used to elicit preferences: conjoint analysis/discrete choice experiment methods (n = 27), contingent valuation (n = 16), time trade-off (n = 4), best-worst scaling (n = 3), multicriteria decision analysis (n = 3), and a standard gamble approach (n = 1). Half of the studies were published after 2016 (52%, 28/54). The most common scenario (n = 39) for eliciting patient preferences was cancer screening. Computed tomography, the most frequently studied imaging modality, was included in 20 studies, and sample sizes ranged from 30 to 3469 participants (mean 552). The mean PREFS score was 3.5 (standard deviation 0.8) for the included studies.

CONCLUSIONS

This review highlights that a variety of quantitative preference methods are being used, as diagnostic imaging technologies continue to evolve. While the number of preference studies in diagnostic imaging has increased with time, most examine preventative care/screening, leaving a gap in knowledge regarding imaging for disease characterization and management.

Attributes in stated preference elicitation studies on colorectal cancer screening and their relative importance for decision-making among screenees: a systematic review

INTRODUCTION

The SIGMO study (Sigmoidoscopy as an evidence-based colorectal cancer screening test - a possible option?) examines screening eligible populations' preferences for colorectal cancer (CRC) screening in Germany using a discrete choice experiment (DCE). Attribute identification and selection are essential for the construction of choice tasks and should be evidence-based. As a part of the SIGMO study this systematic review provides an overview of attributes included in studies eliciting stated preferences for CRC screening tests and their relative importance for decision-making.

METHODS

Systematic search (November 2021) for English-language studies published since January 2000 in PubMed, Embase, Web of Science, Biomedical Reference Collection: Corporate Edition, LIVIVO and PsycINFO. DCEs and conjoint analysis ranking or rating tasks on screening eligible populations' preferences for stool testing, sigmoidoscopy, and/or colonoscopy were included. Attributes were extracted and their relative importance was calculated and ranked. Risk of bias (RoB) of included studies was assessed using a modified GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. Study selection and RoB rating were carried out independently by two reviewers. Data were extracted by one reviewer and checked by another one.

RESULTS

A total of 23 publications on 22 studies were included. Overall RoB was rated as serious/critical for 21 studies and as moderate for 2 studies. Main reasons for high RoB were non-random sampling, low response rates, lack of non-responder analyses, and, to a lesser extent, weaknesses in the measurement instrument and data analysis. Extracted attributes (n = 120) referred to procedure-related characteristics (n = 42; 35%), structural characteristics of health care (n = 24; 20%), test characteristics (n = 23; 19%), harms (n = 16; 13%), benefits (n = 13; 11%), and level of evidence (n = 2; 2%). Most important attributes were reduction in CRC mortality (and incidence) (n = 7), test sensitivity (n = 7), out-of-pocket costs (n = 4), procedure (n = 3), and frequency (n = 2).

CONCLUSIONS

Health preference studies on CRC were found to have a high RoB. The composition of choice tasks revealed a lack of attributes on patient-important outcomes (like incidence reduction), while attributes not considered relevant for individual screening decisions (like sensitivity) were frequently used. Future studies eliciting stated preferences in cancer screening should apply the principles of informed decision-making in attribute identification and selection.

Attributes Characterizing Colorectal Cancer Screening Tests That Influence Preferences of Individuals Eligible for Screening in Germany: A Qualitative Study

PURPOSE

This qualitative study is part of the SIGMO study, which evaluates general populations' preferences for colorectal cancer (CRC) screening in Germany using a discrete choice experiment. Attribute identification and selection are essential in the construction of choice tasks and should be evidence-based ensuring that attributes are relevant to potential beneficiaries and contribute to overall utility. Therefore, this qualitative study aims to identify relevant attributes characterizing CRC screening tests from the perspective of those eligible for screening in Germany.

PATIENTS AND METHODS

Individuals aged 50 to 60 were purposively selected. A questioning route was developed and piloted. Four focus groups (FG) (n=20) were conducted (November 2019) with two moderators and one observer each. FGs were audio recorded, transcribed, and analyzed using qualitative content analysis. Attributes were deductively assigned based on a priori identified attribute categories, and inductively derived.

RESULTS

Across FGs, 24 attributes (n=293 codes) were discussed, five of which (sedation, inability to work, transportation home, predictive values, waiting time for screening colonoscopy) were inductively derived (n=76 codes). Four attributes identified a priori were not addressed in any FG. The most frequently discussed attribute category was procedural characteristics, followed by measures of screening test validity, benefits, harms, and structural characteristics of health care. The most commonly addressed attributes were preprocedural bowel cleansing, kind of procedure, and predictive values.

CONCLUSION

Newly identified attributes characterizing CRC screening tests from an individual's perspective, and a priori identified attributes not addressed by any FG stress the added value of qualitative research and thereby the importance of applying a mix of methods in identifying and selecting attributes for the construction of choice tasks. This study meets the requirements for a transparent and detailed presentation of the qualitative methods used in this process, which has rarely been the case before.

Evaluating Discrete Choice Experiment Willingness to Pay [DCE-WTP] analysis, and Relative Social Willingness to Pay [RS-WTP] analysis in a Health Technology Assessment of a treatment for an ultra-rare childhood disease [CLN2]

BACKGROUND

: Conventional cost-effectiveness analysis [CEA] using cost per QALY thresholds may counteract other incentives introduced to foster development of treatments for rare and ultra-rare diseases. Therefore, alternative economic evaluation methods were explored, namely Discrete Choice Experiment Willingness to Pay (DCE-WTP) and Relative Social Willingness to Pay (RS-WTP), to value interventions for an ultra-rare childhood disease, Neuronal Ceroid Lipofuscinosis type 2 (CLN2).

RESEARCH DESIGN AND METHODS

Treatment for CLN2 was valued from a citizen's ("social") perspective using DCE-WTP and RS-WTP in a survey of 4,009 United Kingdom [UK] adults. Three attributes (initial quality of life, treatment effect, and life expectancy) were used in both analyses. For DCE-WTP a cost attribute (marginal income tax increase) was also included. Optimal econometric models were identified.

RESULTS

DCE-WTP indicated that UK adults are willing to pay incremental increases through taxation for improvements in CLN2 attributes. RS-WTP identified a willingness to allocate >40% of a pre-assigned healthcare budget to prevent child mortality and approximately 15% for improved health status.

CONCLUSIONS

Both techniques illustrated substantive social WTP for CLN2 interventions, despite the small number of children benefitting. This highlights a gap between UK citizens' willingness to spend on rare disease interventions and current funding policies.

Individuals' Preferences for Esophageal Cancer Screening: A Discrete Choice Experiment

OBJECTIVES

The increasing incidence of esophageal adenocarcinoma (EAC) and the dismal prognosis has stimulated interest in the early detection of EAC. Our objective was to determine individuals' preferences for EAC screening and to assess to what extent procedural characteristics of EAC screening tests predict willingness for screening participation.

METHODS

A discrete choice experiment questionnaire was sent by postal mail to 1000 subjects aged 50 to 75 years who were randomly selected from the municipal registry in the Netherlands. Each subject answered 12 discrete choice questions of 2 hypothetical screening tests comprising 5 attributes: EAC-related mortality risk reduction, procedure-related pain and discomfort, screening location, test specificity, and costs. A multinomial logit model was used to estimate individuals' preferences for each attribute level and to calculate expected rates of uptake.

RESULTS

In total, 375 individuals (37.5%) completed the questionnaire. Test specificity, pain and discomfort, mortality reduction, and out-of-pocket costs all had a significant impact on respondents' preferences. The average expected uptake of EAC screening was 62.8% (95% confidence interval [CI] 61.1-64.5). Severe pain and discomfort had the largest impact on screening uptake (-22.8%; 95% CI -26.8 to -18.7). Male gender (β 2.81; P < .001), cancer worries (β 1.96; P = .01), endoscopy experience (β 1.46; P = .05), and upper gastrointestinal symptoms (β 1.50; P = .05) were significantly associated with screening participation.

CONCLUSIONS

EAC screening implementation should consider patient preferences to maximize screening attendance uptake. Based on our results, an optimal screening test should have high specificity, cause no or mild to moderate pain or discomfort, and result in a decrease in EAC-related mortality.

Disutility associated with cancer screening programs: A systematic review

Objectives

Disutility allows to identify how much population values intervention-related harms contributing to knowledge on the benefits/harms ratio of cancer screening programs. This systematic review evaluates disutility related to cancer screening applying a utility theory framework.

Methods

Using a predefined protocol, Embase, Medline Ovid, Web of Science, Cochrane, Google scholar and supplementary sources were systematically searched. The framework grouped disutilities associated with breast, cervical, lung, colorectal, and prostate cancer screening programs into the screening, diagnostic work up, and treatment phases. We assessed the quality of included studies according to the relevance to target population, risk of bias, appropriateness of measure and the time frame.

Results

Out of 2840 hits, we included 38 studies, of which 27 measured (and others estimated) disutilities. Around 70% of studies had medium to high-level quality. Measured disutilities and Quality Adjusted Life Years loss were 0–0.03 and 0–0.0013 respectively in screening phases. Both disutilities and Quality Adjusted Life Years loss had similar ranges in diagnostic work up (0–0.26), and treatment (0.09–0.27) phases. We found no measured disutilities available for lung cancer screening and—little evidence for disutilities in treatment phase. Almost 40% of the estimated disutility values were above the range of measured ones.

Conclusions

Cancer screening programs led to low disutities related to screening phase, and low to moderate disutilities related to diagnostic work up and treatment phases. These disutility values varied by the measurement instrument applied, and were higher in studies with lower quality. The estimated disutility values comparing to the measured ones tended to overestimate the harms.

[Eliciting women’s preferences for breast cancer screening]

INTRODUCTION

Over the past decade, the balance between the benefits and harms of breast cancer screening (BCS) has been widely debated. To date, no French study has interrogated women's points of view and preferences (in the economic sense) for this controversial screening. This study aims to bridge this gap. We aimed to elicit women's trade-offs between the benefits and harms of BCS.

METHODS

A discrete choice experiment questionnaire was developed and administered by a survey institute to French women in order to elicit their preferences and trade-offs between the benefits and risks of BCS (i.e., overdiagnosis and false-positive mammography).

RESULTS

Eight hundred and twelve women, representative of the French general population (age, socioeconomic level, and geographical location), completed the survey. The women would be willing to accept on average 14.1 overdiagnosis cases (median = 9.6) and 47.8 women with a false-positive result (median = 27.2) to avoid one BC-related death. Results from our simulations predict that less than 50% of women would be willing to accept 10 overdiagnosis cases (respectively, 30 women with a false-positive mammography) for one BC-related death avoided.

CONCLUSION

Women are sensitive to both the benefits and harms of BC screening and their preferences are highly heterogeneous. Providing balanced information on both benefits and harms to women through an informed decision-making process would be more respectful of women's preferences.

Women's Benefits and Harms Trade-Offs in Breast Cancer Screening: Results from a Discrete-Choice Experiment

BACKGROUND

Over the past decade, the benefits and harms balance of breast cancer (BC) screening has been widely debated.

OBJECTIVES

To elicit women's trade-offs between the benefits and harms of BC screening and to analyze the main determinants of these trade-offs.

METHODS

A discrete-choice experiment with seven attributes depicting BC screening programs including varying levels of BC mortality, overdiagnosis, and false-positive result was used. Eight hundred twelve women aged 40 to 74 years with no personal history of BC recruited by a survey institute and representative of the French general population (age, socioeconomic level, and geographical location) completed the discrete-choice experiment. Preference heterogeneity was investigated using generalized multinomial logit models from which individual trade-offs were derived, and their main determinants were assessed using generalized linear models. Screening acceptance rates under various benefits and harms ratios were simulated on the basis of the distribution of individual preferences.

RESULTS

The women would be willing to accept on average 14.1 overdiagnosis cases (median = 9.6) and 47.8 false-positive results (median = 27.2) to avoid one BC-related death. After accounting for preference heterogeneity, less than 50% of women would be willing to accept 10 overdiagnosis cases for one BC-related death avoided. Screening acceptance rates were higher among women with higher socioeconomic level and lower among women with poor health.

CONCLUSIONS

Women are sensitive to both the benefits and the harms of BC screening and their preferences are highly heterogeneous. Our study provides useful results for public health authorities and clinicians willing to improve their recommendations of BC screening on the basis of women's preferences.

Stated Preference for Cancer Screening: A Systematic Review of the Literature, 1990-2013

Introduction

Stated-preference methods provide a systematic approach to quantitatively assess the relative preferences for features of cancer screening tests. We reviewed stated-preference studies for breast, cervical, and colorectal cancer screening to identify the types of attributes included, the use of questions to assess uptake, and whether gaps exist in these areas. The goal of our review is to inform research on the design and promotion of public health programs to increase cancer screening.

Methods

Using the PubMed and EconLit databases, we identified studies published in English from January 1990 through July 2013 that measured preferences for breast, cervical, and colorectal cancer screening test attributes using conjoint analysis or a discrete-choice experiment. We extracted data on study characteristics and results. We categorized studies by whether attributes evaluated included screening test, health care delivery characteristics, or both.

Results

Twenty-two studies met the search criteria. Colorectal cancer was the most commonly studied cancer of the 3. Fifteen studies examined only screening test attributes (efficacy, process, test characteristics, and cost). Two studies included only health care delivery attributes (information provided, staff characteristics, waiting time, and distance to facility). Five studies examined both screening test and health care delivery attributes. Overall, cancer screening test attributes had a significant effect on a patient’s selection of a cancer screening test, and health care delivery attributes had mixed effects on choice.

Conclusion

A growing number of studies examine preferences for cancer screening tests. These studies consistently find that screening test attributes, such as efficacy, process, and cost, are significant determinants of choice. Fewer studies have examined the effect of health care delivery attributes on choice, and the results from these studies are mixed. There is a need for additional studies on the barriers to cancer screening uptake, including health care delivery attributes, and the effect of education materials on preferences.

WHAT IS THE ROLE OF COMMUNITY PREFERENCE INFORMATION IN HEALTH TECHNOLOGY ASSESSMENT DECISION MAKING? A CASE STUDY OF COLORECTAL CANCER SCREENING

OBJECTIVES

The aim of this study was to determine the role of community preference information from discrete choice studies of colorectal cancer (CRC) screening in health technology assessment (HTA) reports and subsequent policy decisions.

METHODS

We undertook a systematic review of discrete choice studies of CRC screening. Included studies were reviewed to assess the policy context of the research. For those studies that cited a recent or pending review of CRC screening, further searches were undertaken to determine the extent to which community preference information was incorporated into the HTA decision-making process.

RESULTS

Eight discrete choice studies that evaluated preferences for CRC screening were identified. Four of these studies referred to a national or local review of CRC screening in three countries: Australia, Canada, and the Netherlands. Our review of subsequently released health policy documents showed that while consideration was given to community views on CRC, policy was not informed by discrete choice evidence.

CONCLUSIONS

Preferences and values of patients are increasingly being considered "evidence" to be incorporated into HTA reports. Discrete choice methodology is a rigorous quantitative method for eliciting preferences and while as a methodology it is growing in profile, it would appear that the results of such research are not being systematically translated or integrated into HTA reports. A formalized approach is needed to incorporate preference literature into the HTA decision-making process.

Public Perceptions of the Benefits and Risks of Newborn Screening

BACKGROUND

Growing technological capacity and parent and professional advocacy highlight the need to understand public expectations of newborn population screening.

METHODS

We administered a bilingual (French, English) Internet survey to a demographically proportional sample of Canadians in 2013 to assess preferences for the types of diseases to be screened for in newborns by using a discrete choice experiment. Attributes were: clinical benefits of improved health, earlier time to diagnosis, reproductive risk information, false-positive (FP) results, and overdiagnosed infants. Survey data were analyzed with a mixed logit model to assess preferences and trade-offs among attributes, interaction between attributes, and preference heterogeneity.

RESULTS

On average, respondents were favorable toward screening. Clinical benefits were the most important outcome; reproductive risk information and early diagnosis were also valued, although 8% disvalued early diagnosis, and reproductive risk information was least important. All respondents preferred to avoid FP results and overdiagnosis but were willing to accept these to achieve moderate clinical benefit, accepting higher rates of harms to achieve significant benefit. Several 2-way interactions between attributes were statistically significant: respondents were willing to accept a higher FP rate for significant clinical benefit but preferred a lower rate for moderate benefit; similarly, respondents valued early diagnosis more when associated with significant rather than moderate clinical benefit.

CONCLUSIONS

Members of the public prioritized clinical benefits for affected infants and preferred to minimize harms. These findings suggest support for newborn screening policies prioritizing clinical benefits over solely informational benefits, coupled with concerted efforts to avoid or minimize harms.

What Influences Patients' Decisions When Choosing a Health Care Provider? Measuring Preferences of Patients with Knee Arthrosis, Chronic Depression, or Alzheimer's Disease, Using Discrete Choice Experiments

OBJECTIVE

To investigate what influences patients' health care decisions and what the implications are for the provision of information on the quality of health care providers to patients.

DATA SOURCES/STUDY SETTING

Dutch patient samples between November 2006 and February 2007.

STUDY DESIGN

Discrete choice experiments were conducted in three patient groups to explore what influences choice for health care providers.

DATA COLLECTION

Data were obtained from 616 patients with knee arthrosis, 368 patients with chronic depression, and 421 representatives of patients with Alzheimer's disease.

PRINCIPAL FINDINGS

The three patients groups chose health care providers on a different basis. The most valued attributes were effectiveness and safety (knee arthrosis); continuity of care and relationship with the therapist (chronic depression); and expertise (Alzheimer's disease). Preferences differed between subgroups, mainly in relation to patients' choice profiles, severity of disease, and some background characteristics.

CONCLUSIONS

This study showed that there is substantial room for (quality) information about health care providers in patients' decision processes. This information should be tailor-made, targeting specific patient segments, because different actors and factors play a part in their search and selection process.

Older adults' preferences for colorectal cancer-screening test attributes and test choice

BACKGROUND

Understanding which attributes of colorectal cancer (CRC) screening tests drive older adults' test preferences and choices may help improve decision making surrounding CRC screening in older adults.

MATERIALS AND METHODS

To explore older adults' preferences for CRC-screening test attributes and screening tests, we conducted a survey with a discrete choice experiment (DCE), a directly selected preferred attribute question, and an unlabeled screening test-choice question in 116 cognitively intact adults aged 70-90 years, without a history of CRC or inflammatory bowel disease. Each participant answered ten discrete choice questions presenting two hypothetical tests comprised of four attributes: testing procedure, mortality reduction, test frequency, and complications. DCE responses were used to estimate each participant's most important attribute and to simulate their preferred test among three existing CRC-screening tests. For each individual, we compared the DCE-derived attributes to directly selected attributes, and the DCE-derived preferred test to a directly selected unlabeled test.

RESULTS

Older adults do not overwhelmingly value any one CRC-screening test attribute or prefer one type of CRC-screening test over other tests. However, small absolute DCE-derived preferences for the testing procedure attribute and for sigmoidoscopy-equivalent screening tests were revealed. Neither general health, functional, nor cognitive health status were associated with either an individual's most important attribute or most preferred test choice. The DCE-derived most important attribute was associated with each participant's directly selected unlabeled test choice.

CONCLUSION

Older adults' preferences for CRC-screening tests are not easily predicted. Medical providers should actively explore older adults' preferences for CRC screening, so that they can order a screening test that is concordant with their patients' values. Effective interventions are needed to support complex decision making surrounding CRC screening in older adults.

Developing a discrete choice experiment in Malawi: eliciting preferences for breast cancer early detection services

BACKGROUND

In Malawi, routine breast cancer screening is not available and little is known about women's preferences regarding early detection services. Discrete choice experiments are increasingly used to reveal preferences about new health services; however, selecting appropriate attributes that describe a new health service is imperative to ensure validity of the choice experiment.

OBJECTIVE

To identify important factors that are relevant to Malawian women's preferences for breast cancer detection services and to select attributes and levels for a discrete choice experiment in a setting where both breast cancer early detection and choice experiments are rare.

METHODS

We reviewed the literature to establish an initial list of potential attributes and levels for a discrete choice experiment and conducted qualitative interviews with health workers and community women to explore relevant local factors affecting decisions to use cancer detection services. We tested the design through cognitive interviews and refined the levels, descriptions, and designs.

RESULTS

Themes that emerged from interviews provided critical information about breast cancer detection services, specifically, that breast cancer interventions should be integrated into other health services because asymptomatic screening may not be practical as an individual service. Based on participants' responses, the final attributes of the choice experiment included travel time, health encounter, health worker type and sex, and breast cancer early detection strategy. Cognitive testing confirmed the acceptability of the final attributes, comprehension of choice tasks, and women's abilities to make trade-offs.

CONCLUSION

Applying a discrete choice experiment for breast cancer early detection was feasible with appropriate tailoring for a low-income, low-literacy African setting.

Assessing stated preferences for colorectal cancer screening: a critical systematic review of discrete choice experiments

BACKGROUND

It is well established that screening is effective in reducing the incidence and mortality associated with colorectal cancer (CRC). National screening programs have been implemented in many countries; however, uptake remains an issue. Understanding patient preferences may assist in shaping screening programs and tailoring information about screening tests.

OBJECTIVE

Our objective was to undertake a systematic review of discrete choice experiments (DCEs) of CRC screening.

METHODS

A systematic review of DCEs of CRC screening was undertaken in an average-risk general population. The methodological qualities of the studies were assessed using a standard checklist outlining best practice for conjoint studies.

RESULTS

Nine studies met the selection criteria. Meta-analysis was not possible due to the heterogeneity of the data and methods. However, in eight studies, attributes describing accuracy and/or clinical effectiveness were reported to be statistically significant. We also found that individuals were willing to trade-off other attributes such as an increased risk of complications to gain greater clinical benefits. Screening was also preferred to non-screening by the majority of respondents, regardless of the test used.

CONCLUSIONS

Understanding and incorporating individuals' preferences in decision making is increasingly considered essential in the health field. Data from DCEs can provide valuable insights into the trade-offs individuals are willing to undertake in respect to CRC screening. Such insights can be used by decision makers to identify screening tests that could maximize informed uptake. It is likely that, with better reporting and evolving methodology, the contribution that DCEs can make to such debates will increase.

Factors affecting breast cancer screening behavior in Japan--assessment using the health belief model and conjoint analysis

BACKGROUND

Japanese women in their 40s or older have been encouraged to attend breast cancer screening. However, the breast cancer screening rate in Japan is not as high as in Europe and the United States. The aim of this study was to identify psychological and personal characteristics of women concerning their participation in breast cancer screening using the Health Belief Model (HBM). In addition, the attributes of screening more easily accepted by participants were analyzed by conjoint analysis.

MATERIALS AND METHODS

In this cross sectional study of 3,200 age 20-69 women, data were collected by an anonymous questionnaire. Questions were based on HBM and personal characteristics, and included attitudes on hypothetical screening attributes. Data of women aged 40-69 were analyzed by logistic regression and conjoint analysis to clarify the factors affecting their participation in breast cancer screening.

RESULTS

Among responses collected from 1,280 women of age 20-69, the replies of 993 women of age 40-69 were used in the analysis. Regarding the psychological characteristics based on HBM, the odds ratios were significantly higher in "importance of cancer screening" (95%CI: 1.21-2.47) and "benefits of cancer screening" (95%CI: 1.09-2.49), whereas the odds ratio was significantly lower in "barriers to participation before cancer screening" (95%CI: 0.27-0.51). Conjoint analysis revealed that the respondents, overall, preferred screening to be low cost and by female staff members. Furthermore, it was also clarified that attributes of screening dominant in decision-making were influenced by the employment status and the type of medical insurance of the women.

CONCLUSIONS

In order to increase participation in breast cancer screening, it is necessary to disseminate accurate knowledge on cancer screening and to reduce barriers to participation. In addition, the attributes of screening more easily accepted were inexpensive, provided by female staff, executed in a hospital and finished in a short time.

Preferences for potential innovations in non-invasive colorectal cancer screening: A labeled discrete choice experiment for a Dutch screening campaign

BACKGROUND

The introduction of innovative non-invasive screening tests (e.g. tests based on stool and blood samples or both) may be a solution to increase colorectal cancer (CRC) screening uptake. However, preferences for these non-invasive screening tests have not been investigated in great detail yet. The purpose of this article therefore is to elicit individuals' preferences for different non-invasive screening tests in a Dutch screening campaign context.

MATERIAL AND METHODS

We investigate preferences by means of a labeled discrete choice experiment. Data of 815 individuals, aged 55-75 years, are used in the analysis.

RESULTS

Multinomial logit model analysis showed that the combi-test is generally preferred over the blood-test and the (currently available) stool-test. Furthermore, besides the large effect of screening test type, there are significant differences in preference depending on participants' socio-demographic background. Finally, the analysis showed a significant positive effect on screening test choice for the attributes sensitivity, risk reduction, and level of evidence and a non-significant effect for the attribute unnecessary follow-up test.

CONCLUSION

Introducing new non-invasive screening tests that are based on a combination of stool and blood samples (or blood sample only) has the potential to increase CRC screening participation compared to the current standard stool-based test.

The effect of presenting information about invasive follow-up testing on individuals' noninvasive colorectal cancer screening participation decision: results from a discrete choice experiment

OBJECTIVES

Many national colorectal cancer screening campaigns have a similar structure. First, individuals are invited to take a noninvasive screening test, and, second, in the case of a positive screening test result, they are advised to undergo a more invasive follow-up test. The objective of this study was to investigate how much individuals' participation decision in noninvasive screening is affected by the presence or absence of detailed information about invasive follow-up testing and how this effect varies over screening tests.

METHODS

We used a labeled discrete choice experiment of three noninvasive colorectal cancer screening types with two versions that did or did not present respondents with detailed information about the possible invasive follow-up test (i.e., colonoscopy) and its procedure. We used data from 631 Dutch respondents aged 55 to 75 years. Each respondent received only one of the two versions (N = 310 for the invasive follow-up test information specification version, and N = 321 for the no-information specification version).

RESULTS

Mixed logit model results show that detailed information about the invasive follow-up test negatively affects screening participation decisions. This effect can be explained mainly by a decrease in choice shares for the most preferred screening test (a combined stool and blood sample test). Choice share simulations based on the discrete choice experiment indicated that presenting invasive follow-up test information decreases screening participation by 4.79%.

CONCLUSIONS

Detailed information about the invasive follow-up test has a negative effect on individuals' screening participation decisions in noninvasive colorectal cancer screening campaigns. This result poses new challenges for policymakers who aim not only to increase uptake but also to provide full disclosure to potential screening participants.

Patients' preferences for gonadotrophin-releasing hormone analogs in in vitro fertilization

BACKGROUND

Gonadotrophin-releasing hormone (GnRH) antagonists reduce ovarian hyperstimulation syndrome (OHSS) at the price of a small reduction in effectiveness compared to GnRH agonists. The aim of this study was to investigate patients' preferences on effectiveness, safety and burden of GnRH analogs.

METHODS

A discrete choice experiment (DCE) and a trade-off question were designed. Patients embarking on assisted reproductive technique treatment were asked to choose between two hypothetical medications which differed in effectiveness, safety and burden.

RESULTS

A total of 172 questionnaires were analyzed. All attributes of the DCE had a statistically significant impact on the preference of the respondents. Respondents were willing to trade off 0.87 and 0.81% effectiveness for a decrease in OHSS risk and for fewer side effects, respectively. Respondents were not willing to trade off effectiveness for 'importance of compliance' (trade-off 0.40%) or a shorter 'duration of treatment' (trade-off 0.26%). The trade-off questions showed that already at a 2.0% increase in pregnancy rate in favor of the agonists, the majority of the respondents changed their preference from antagonists to agonists (2.0%, 95% CI 1.7-2.1).

CONCLUSION

Safety and burden are important to patients, but are not important enough to make up for a small decrease in pregnancy rate.

Ethical issues in colorectal cancer screening

In many countries, colorectal cancer screening is currently an established population screening program due to the evidence on its reduction of colorectal cancer mortality. There is general consensus that colorectal cancer screening meets the screening criteria as proposed by Wilson and Jungner. However, as for all population screening programs, colorectal cancer screening also has disadvantages and thereby entails ethical issues. There are the general issues concerning the introduction of screening programs (e.g. medicalization, overdiagnosis and overtreatment, information provision to screenees), evaluation of cancer screening programs (e.g. lead time and length bias), chosen screening method (e.g. false-positive and false-negative test results, reduction of all-cause mortality, choice between different screening methods). The different colorectal cancer screening methods and the ethical issues concerning colorectal cancer screening will be discussed in this review.

Public preferences for colorectal cancer screening tests: a review of conjoint analysis studies

A wide range of screening technologies is available for colorectal cancer screening. There is demand to discover public preferences for these tests on the rationale that tailoring screening to preferences may improve uptake. This review describes a type of study (conjoint analysis) used to assess people's preferences for colorectal cancer screening tests and critically evaluates research quality using a recently published set of guidelines. Most primary studies assessed preferences for colonoscopy and fecal occult blood testing but newer technologies (e.g., capsule endoscopy) have not yet been evaluated. Although studies often adhered to guidelines, there was limited correspondence between stated preferences and actual screening behavior. Future research should investigate how studies can go beyond the guidelines in order to improve this and also explore how test preferences may differ by important population subgroups.

Insensitivity to scope in contingent valuation studies: reason for dismissal of valuations?

BACKGROUND

The credibility of contingent valuation studies has been questioned because of the potential occurrence of scope insensitivity, i.e. that respondents do not react to higher quantities or qualities of a good.

OBJECTIVE

The aim of this study was to examine the extent of scope insensitivity and to assess the relevance of potential explanations that may help to shed light on how to appropriately handle this problem in contingent valuation studies.

METHODS

We surveyed a sample of 2004 men invited for cardiovascular disease screening. Each respondent had three contingent valuation tasks from which their sensitivity to larger risk reductions (test 1) and to change in travel costs associated with participation (test 2) could be assessed. Participants were surveyed while waiting for their screening session. Non-participants were surveyed by postal questionnaire.

RESULTS

The sample was overall found to be sensitive to scope, testing at the conventional sample-mean level. At the individual respondent level, however, more than half of the respondents failed the tests. Potential determinants for failing the tests were examined in alternative regression models but few consistent relationships were identified. One exception was the influence of more detailed information, which was positively associated with willingness to pay and negatively associated with scope sensitivity.

CONCLUSION

Possible explanations for scope insensitivity are discussed; if cognitive limitations, emotional load and mental budgeting explain scope insensitivity there are grounds for rejecting valuations, whereas other factors such as the alternative theoretical framework of regret theory may render insensitivity to scope a result of rational thinking. It is concluded that future contingent valuation studies should focus more on extracting the underlying motives for the stated preferences in order to appropriately deal with responses that are seemingly irrational, and which may lead to imprecise welfare estimates.

Validity and Reliability of Willingness-to-Pay Estimates: Evidence from Two Overlapping Discrete-Choice Experiments

BACKGROUND

Discrete-choice experiments (DCEs), while becoming increasingly popular, have rarely been tested for validity and reliability.

OBJECTIVE

To address the issues of validity and reliability of willingness-to-accept (WTA) values obtained from DCEs. In particular, to examine whether differences in the attribute set describing a hypothetical product have an influence on preferences and willingness-to-pay (WTP) values of respondents.

METHODS

Two DCEs were designed, featuring hypothetical insurance contracts for Swiss healthcare. The contract attributes were pre-selected in expert sessions with representatives of the Swiss healthcare system, and their relevance was checked in a pre-test. Experiment A contained rather radical health system reform options, while experiment B concentrated on more familiar elements such as co-payment and the benefit catalogue. Three attributes were present in both experiments: delayed access to innovation ('innovation'), restricted drug benefit ('generics'), and the change in the monthly premium ('premium'). The issue to be addressed was whether WTA values for the overlapping attributes were similar, even though they were embedded in widely differing choice sets.Two representative telephone surveys with 1000 people aged >25 years were conducted independently in the German and French parts of Switzerland during September 2003. Socioeconomic variables collected included age, sex, education, total household income, place of residence, occupation, and household size. Three models were estimated (a simple linear model, a model allowing interaction of the price attribute with socioeconomic characteristics, and a model with a full set of interaction terms).

RESULTS

The socioeconomic characteristics of the two samples were very similar. Theoretical validity tends to receive empirical support in both experiments in all cases where economic theory makes predictions concerning differences between socioeconomic groups. However, a systematic inappropriate influence on measured WTA seems to be present in at least one experiment. This is likely to be experiment A, in which respondents were far less familiar with proposed alternatives than in experiment B.

CONCLUSIONS

Measuring preferences for major, little-known innovations in a reliable way seems to present particular challenges for experimental research.

The COMPASs Study: Community Preferences for Prostate cAncer Screening. Protocol for a quantitative preference study

Background Prostate cancer screening using prostate-specific antigen (PSA) testing remains controversial. Trade-offs between the potential benefits and downsides of screening must be weighed by men deciding whether to participate in prostate cancer screening; little is known about benefit:harm trade-offs men are willing to accept. Methods/Design The Community Preferences for Prostate Cancer Screening (COMPASs) Study examines Australian men's preferences for prostate cancer screening using PSA testing. The aims are to (1) determine which factors influence men's decision to participate in prostate cancer screening or not and (2) determine the extent of trade-offs between benefits and harms that men are willing to accept in making these decisions. Quantitative methods will be used to assess men's preferences for PSA screening. Using data on the quantitative outcomes of PSA testing from the published literature, a discrete choice study will be designed to quantitatively assess men's preferences. A web-based survey will be conducted in approximately 1000 community respondents aged 40-69 years, stratified by family history of prostate cancer, to assess men's preferences for PSA testing. A mixed logit model will be used; model results will be expressed as parameter estimates (β) and the odds of choosing screening over no screening. Trade-offs between attributes will also be calculated. Ethics and Dissemination The COMPASs study has been approved by the University of Sydney, Human Research Ethics committee (Protocol number 13186). The results will be published in internal reports, in peer-reviewed scientific journals as well as via conference presentations.

Healthy-days time equivalents for outcomes of acute rotavirus infections

Rotavirus is the most common cause of severe gastroenteritis in infants and young children worldwide. Health-state utility measures used in economic evaluations of rotavirus vaccines do not reflect differences between mild and severe symptoms of rotavirus gastroenteritis and, therefore, do not adequately capture preferences for non-fatal outcomes associated with rotavirus common in industrialized countries. This paper describes the development and results of a survey specifically designed to develop quality-adjusted time equivalents for rotavirus gastroenteritis among a sample of parents with young children in the United States as an alternative to conventional QALY measures in assessing cost-effectiveness.

The influence of information and private versus public provision on preferences for screening for prostate cancer: a willingness-to-pay study

This study investigates the influence of information and public versus private provision on preferences for introducing screening (i.e. PSA-test) for prostate cancer in Denmark. The aim is to disclose if preferences (measured as willingness-to-pay) are influenced by whether the service is provided by the private or public health care sector, and the extent to which negative information on the PSA-test influences the perceptions of the screening programme. It is also investigated whether the impact of information differs dependent on public-private provision. A random sample of the Danish male population (all between 50 and 70 years of age) were invited to fill out a web-based questionnaire. It was found that two thirds of the respondents were willing to participate and willing to pay for a public intervention programme, when provided with all relevant information. In contrast, only approximately one third were so inclined if a prostate cancer screening service was offered by private clinics. Results suggest that public provision framing increases the perceived value of the screening programme, and that the provision of full information regarding the negative characteristics of the programme decreases programme valuation.

Discrete choice experiments to measure consumer preferences for health and healthcare

To investigate the impact of health policies on individual well-being, estimate the value to society of new interventions or policies, or predict demand for healthcare, we need information about individuals' preferences. Economists usually use market-based data to analyze preferences, but such data are limited in the healthcare context. Discrete choice experiments are a potentially valuable tool for elicitation and analysis of preferences and thus, for economic analysis of health and health programs. This paper reviews the use of discrete choice experiments to measure consumers' preferences for health and healthcare. The paper provides an overview of the approach and discusses issues that arise when using discrete choice experiments to assess individuals' preferences for health and healthcare.

What determines individuals' preferences for colorectal cancer screening programmes? A discrete choice experiment

INTRODUCTION

In many countries uptake of colorectal cancer (CRC) screening remains low.

AIM

To assess how procedural characteristics of CRC screening programmes determine preferences for participation and how individuals weigh these against the perceived benefits from participation in CRC screening.

METHODS

A discrete choice experiment was conducted among subjects in the age group of 50-75 years, including both screening-naïve subjects and participants of a CRC screening programme. Subjects were asked on their preferences for aspects of CRC screening programmes using scenarios based on pain, risk of complications, screening location, preparation, duration of procedure, screening interval and risk reduction of CRC-related death.

RESULTS

The response was 31% (156/500) for screening-naïve and 57% (124/210) for CRC screening participants. All aspects proved to significantly influence the respondents' preferences. For both groups combined, respondents required an additional relative risk reduction of CRC-related death by a screening programme of 1% for every additional 10 min of duration, 5% in order to expose themselves to a small risk of complications, 10% to accept mild pain, 10% to undergo preparation with an enema, 12% to use 0.75l of oral preparation combined with 12h fasting and 32% to use an extensive bowel preparation. Screening intervals shorter than 10 years were significantly preferred to a 10-year screening interval.

CONCLUSION

This study shows that especially type of bowel preparation, risk reduction of CRC related death and length of screening interval influence CRC screening preferences. Furthermore, improving awareness on CRC mortality reduction by CRC screening may increase uptake.

Preferences for colorectal cancer screening strategies: a discrete choice experiment

Background:

Guidelines underline the role of individual preferences in the selection of a screening test, as insufficient evidence is available to recommend one screening test over another. We conducted a study to determine the preferences of individuals and to predict uptake for colorectal cancer (CRC) screening programmes using various screening tests.

Methods:

A discrete choice experiment (DCE) questionnaire was distributed among naive subjects, yet to be screened, and previously screened subjects, aged 50–75 years. Subjects were asked to choose between scenarios on the basis of faecal occult blood test (FOBT), flexible sigmoidoscopy (FS), total colonoscopy (TC) with various test-specific screening intervals and mortality reductions, and no screening (opt-out).

Results:

In total, 489 out of 1498 (33%) screening-naïve subjects (52% male; mean age±s.d. 61±7 years) and 545 out of 769 (71%) previously screened subjects (52% male; mean age±s.d. 61±6 years) returned the questionnaire. The type of screening test, screening interval, and risk reduction of CRC-related mortality influenced subjects’ preferences (all P<0.05). Screening-naive and previously screened subjects equally preferred 5-yearly FS and 10-yearly TC (P=0.24; P=0.11), but favoured both strategies to annual FOBT screening (all P-values <0.001) if, based on the literature, realistic risk reduction of CRC-related mortality was applied. Screening-naive and previously screened subjects were willing to undergo a 10-yearly TC instead of a 5-yearly FS to obtain an additional risk reduction of CRC-related mortality of 45% (P<0.001).

Conclusion:

These data provide insight into the extent by which interval and risk reduction of CRC-related mortality affect preferences for CRC screening tests. Assuming realistic test characteristics, subjects in the target population preferred endoscopic screening over FOBT screening, partly, due to the more favourable risk reduction of CRC-related mortality by endoscopy screening. Increasing the knowledge of potential screenees regarding risk reduction by different screening strategies is, therefore, warranted to prevent unrealistic expectations and to optimise informed choice.

Patients' preferences for scoliosis brace treatment: a discrete choice experiment

STUDY DESIGN

Discrete choice experiment.

OBJECTIVE

To investigate the reduction in the risk of surgery that scoliosis patients would require in order to consider brace treatment as acceptable, and to elicit the trade-offs individuals make between characteristics of brace treatment.

SUMMARY OF BACKGROUND DATA

The effectiveness of brace treatment in idiopathic scoliosis patients has not been established in randomized controlled trials (RCTs). Treatment with a brace can be quite bothersome. Patients' preferences for brace treatment are unknown. Insight into patients' preferences for (characteristics of) brace treatment will be useful for future trials and for the development of braces that may optimize compliance with brace treatment.

METHODS

A total of 197 patients who had completed treatment (brace and/or surgery) for scoliosis were approached for the study, of which 135 gave informed consent. A discrete choice experiment was designed in which patients had to choose between hypothetical brace treatment profiles that differed in following 4 treatment attributes: effectiveness, visibility, discomfort, and treatment duration. A multinomial logit model was used to analyze the relative importance of these attributes. Subgroup analyses were conducted for brace-only, brace-surgery, and surgery-only patients.

RESULTS

The response rate was 86% (116/135). All treatment attributes proved to be important for patients' choices. All subgroups were prepared to initiate treatment with a Boston brace if the brace would reduce the need for surgery by 53%. Risk reductions in a range of 32% to 74% were required for acceptance of a treatment duration of 3 years.

CONCLUSION

Scoliosis patients stated to be prepared to undergo brace treatment only if it provides sizeable reduction of the risk of surgery. Effectiveness and discomfort in wearing a brace were the most important determinants of the choices. These results are important if RCTs would conclusively establish that bracing is effective, and show directions for the further technical development of braces to increase the compliance with brace treatment.

How do physician assessments of patient preferences for colorectal cancer screening tests differ from actual preferences? A comparison in Canada and the United States using a stated-choice survey

BACKGROUND

Patient preferences can affect colorectal cancer (CRC) screening test use. We compared utility-based preferences for alternative CRC screening tests from a stated-preference discrete-choice survey of the general population and physicians in Canada and the United States.

METHODS

General population respondents (Canada, n = 501; US, n = 1087) participated in a survey with 12 choice scenarios and 9 CRC screening test attributes. Physicians (n = 100, both Canada and US) reported expected patient preferences. We estimated relative importance of attributes using bivariate probit regression analysis and calculated willingness-to-pay for various CRC screening tests.

RESULTS

In 28 and 31% of scenarios, Canadian and US respondents, respectively, chose no screening over a hypothetical test. Canadian (45%) and US (46%) physicians expected patients to choose no screening more often. For all groups the most important attribute was sensitivity, but physicians' perception of patients' preferences are significantly different from actual preferences. Other key attributes are those related to test performance or the testing process. Fecal DNA, colonoscopy, and virtual colonoscopy were the most preferred tests by all groups, but respondents were willing-to-pay more than physicians predicted.

CONCLUSION

Physicians' perception of patients' preferences are quite different from those of the general population. However, among general population and physicians, Canadian and US preferences were similar.

Eliciting population preferences for mass colorectal cancer screening organization

INTRODUCTION

The implementation of mass colorectal cancer (CRC) screening is a public health priority. Population participation is fundamental for the success of CRC screening as for any cancer screening program. The preferences of the population may influence their likelihood of participation.

OBJECTIVES

The authors sought to elicit population preferences for CRC screening test characteristics to improve the design of CRC screening campaigns.

METHODS

A discrete choice experiment was used. Questionnaires were compiled with a set of pairs of hypothetical CRC screening scenarios. The survey was conducted by mail from June 2006 to October 2006 on a representative sample of 2000 inhabitants, aged 50 to 74 years from the northwest of France, who were randomly selected from electoral lists. Questionnaires were sent to 2000 individuals, each of whom made 3 or 4 discrete choices between hypothetical tests that differed in 7 attributes: how screening is offered, process, sensitivity, rate of unnecessary colonoscopy, expected mortality reduction, method of screening test result transmission, and cost.

RESULTS

Complete responses were received from 656 individuals (32.8%). The attributes that influenced population preferences included expected mortality reduction, sensitivity, cost, and process. Participants from high social classes were particularly influenced by sensitivity.

CONCLUSIONS

The results demonstrate that the discrete choice experiment provides information on patient preferences for CRC screening: improving screening program effectiveness, for instance, by improving test sensitivity (the most valued attribute) would increase satisfaction among the general population with regard to CRC screening programs. Additional studies are required to study how patient preferences actually affect adherence to regular screening programs.

A labelled discrete choice experiment adds realism to the choices presented: preferences for surveillance tests for Barrett esophagus

Background

Discrete choice experiments (DCEs) allow systematic assessment of preferences by asking respondents to choose between scenarios. We conducted a labelled discrete choice experiment with realistic choices to investigate patients' trade-offs between the expected health gains and the burden of testing in surveillance of Barrett esophagus (BE).

Methods

Fifteen choice scenarios were selected based on 2 attributes: 1) type of test (endoscopy and two less burdensome fictitious tests), 2) frequency of surveillance. Each test-frequency combination was associated with its own realistic decrease in risk of dying from esophageal adenocarcinoma. A conditional logit model was fitted.

Results

Of 297 eligible patients (155 BE and 142 with non-specific upper GI symptoms), 247 completed the questionnaire (84%). Patients preferred surveillance to no surveillance. Current surveillance schemes of once every 1–2 years were amongst the most preferred alternatives. Higher health gains were preferred over those with lower health gains, except when test frequencies exceeded once a year. For similar health gains, patients preferred video-capsule over saliva swab and least preferred endoscopy.

Conclusion

This first example of a labelled DCE using realistic scenarios in a healthcare context shows that such experiments are feasible. A comparison of labelled and unlabelled designs taking into account setting and research question is recommended.

Does attribute framing in discrete choice experiments influence willingness to pay? Results from a discrete choice experiment in screening for colorectal cancer

OBJECTIVE

Recent reviews of discrete choice methodology identified methodological issues warranting further exploration, including the issue of "framing." The objective of this study was to conduct a methodological exploration of the effect of attribute framing on marginal rates of substitution (MRS), including willingness to pay (WTP) from a discrete choice experiment (DCE), within the context of colorectal cancer screening preferences.

METHODS

The survey, a fractional factorial design of a two-alternative, unlabeled experiment, was mailed to a sample of 1920 subjects in NSW, Australia. Participants were randomized to one of four alternative "frames" of information. Attributes included: accuracy of the test for finding cancers, accuracy of the test for finding large polyps, how good the test is at saying you don't have cancer, cost, dietary and medication restrictions and sample collection. A mixed logit model was used to estimate preferences; MRS between attributes, including WTP, was calculated.

RESULTS

A total of 1157 surveys from 1920 (60.2%) were returned. Accuracy of the test for finding cancer was most likely to influence choice of test, followed by accuracy of the test for finding large polyps. Under some circumstances, framing of the attributes (e.g., cancers found vs. cancers missed) influenced the relative importance of attributes. Attribute framing significantly influenced estimates of WTP, and benefit: harm trade-offs that were calculated from MRS.

CONCLUSIONS

Attribute framing can influence willingness to pay and benefit: harm trade-offs from DCEs. Appropriate design and analysis methods should be explored to further characterize the influence and extent of framing in discrete choice studies.

What outcomes are important to patients with long term conditions? A discrete choice experiment

OBJECTIVE

To assess how much patients with long-term conditions value self-efficacy (i.e., confidence in their ability to manage their condition) compared with other health outcomes, including measures of quality of life, and process outcomes including access to General Practitioners.

METHODS

Discrete Choice Experiment (DCE) set in UK community settings.

PARTICIPANTS

367 patients (mean age 57.5) living in the community with a wide range of self-defined long-term conditions.

MAIN OUTCOME MEASURES

The relative value that individuals place on four specific outcomes, namely, self-efficacy, Health Related Quality of Life (HRQoL), access to General Practitioners, and level of isolation.

RESULTS

Most responders completed their questionnaire in a consistent manner. Most valuations of outcomes were in the expected direction and were statistically significant. A substantial minority of responders exhibited counter-intuitive preferences. The existence of a significant constant in all models raised concerns about model misspecification. Nevertheless, all models showed that participants were willing to trade substantial reductions in their HRQoL for improvements in their self-efficacy.

CONCLUSIONS

The majority of patients with chronic conditions were able to complete the DCE questionnaires. However, the existence of counter-intuitive preferences and evidence of model misspecification require further investigation. These issues are largely overlooked in the health economics literature. Self-efficacy is an important outcome for this group and is not included explicitly in conventional HRQoL measures. This is potentially important where decisions are made on the basis of cost-effectiveness using Quality Adjusted Life Years as the metric. Exclusion of these outcomes may lead to the cost-effectiveness of these interventions being understated.

Pecuniary compensation increases participation in screening for colorectal cancer

The participation rate in medical screening programmes is typically below 100%, which means that not all potential health benefits are fully exploited. In this paper, the prospect of pecuniary compensation is tested as a method of increasing the participation rate. We propose a model explaining the individual's probability of participating in screening for colorectal cancer when he is offered pecuniary compensation, given that he did not participate when first invited. The participant's decision is based on both known and uncertain factors. The estimation is conducted in two steps, where a binary probit model is used in each. We find that pecuniary compensation increases the probability of participation, and that an individual's participation probability systematically varies with variables such as travel expenses, income, age, education level, expected benefit from the screening, use of health-care services, genetic predisposition and subjective health status. Using the results from the estimation, we predict changes in the participation rate for different levels of compensation and estimate the cost per additional individual screened. The cost per additional individual screened is 808, including 25 in compensation; this cost increases with the level of compensation.

Preferences of GPs and patients for preventive osteoporosis drug treatment: a discrete-choice experiment

BACKGROUND

Osteoporotic fractures have a serious economic impact on society and on the quality of life of patients. Differences in opinions on the desirability of preventive treatment initiation may hamper the process and outcome of shared decision making between physician and patient.

OBJECTIVE

To evaluate and compare preferences of GPs and patients for preventive osteoporosis drug treatment.

METHODS

Discrete-choice experiment (DCE) involving 34 general practices in the area of Rotterdam, the Netherlands. Participants included 40 GPs and 120 women aged > or = 60 years who participated in a study on osteoporosis case finding. We included any woman aged >60 years, with an over-representation of women with a high fracture risk (n = 60).

OUTCOMES

(i) The relative weights that GPs and patients place on five treatment attributes of preventive osteoporosis drug treatment: effectiveness, nausea as an adverse effect, total treatment duration, route of drug administration and out-of-pocket costs; and (ii) the determinants of any differences in preferences between GPs and patients.

RESULTS

The response rate was 40/59 (68%) for GPs and 120/181 (66%) for patients. All treatment attributes proved to be important for preferences of GPs and patients. GPs had a significantly less favourable attitude towards preventive osteoporosis drug treatment than patients; they placed significantly higher values on effectiveness of preventive drug treatment and short total preventive treatment duration than patients.

CONCLUSIONS

GPs and patients showed different preferences towards preventive osteoporosis drug treatment. Addressing each of these differences may have a positive effect on the process and outcomes of shared decision making regarding preventive treatment initiation.

Preferences for colorectal cancer screening among racially/ethnically diverse primary care patients

BACKGROUND

Incorporating patients' preferences into colorectal cancer (CRC) screening recommendations has been identified as a potential mechanism for increasing adherence. This study used conjoint analysis to describe variation in CRC screening preferences among racially/ethnically diverse primary care patients.

METHODS

We recruited patients ages 50-80 of a large practice-based research network stratified by white, African American, or Hispanic race/ethnicity to complete a preference assessment instrument. Participants were asked to rate 8 hypothetical CRC screening test scenarios comprised of different combinations of 5 attributes and 6 scenarios designed to depict guideline-recommended CRC screening tests (eg, fecal occult blood test, flexible sigmoidoscopy, colonoscopy, and double contrast barium enema) including new technology (eg, virtual colonoscopy, fecal immunochemical test). Responses were used to calculate the overall importance of test attributes, the relative importance of attribute levels, and to identify factors associated with preferences.

RESULTS

Two hundred twelve primary care patients were recruited to the study (74 white, 60 African American, 78 Hispanic). Of the guideline-recommended tests, 37% preferred COL, 31% FOBT, 15% BE, and 9% SIG. Ratings of new technology tests were significantly (P < 0.05) higher than ratings of guideline-recommended tests. The order of the importance of attributes was: what the test involved (37%), accuracy (19%), frequency (17%), discomfort (15%), and preparation (13%). Part-worth utilities for 1 attribute showed that collecting a stool sample was most preferable and endoscopy without sedation least preferable. Multivariate regression found that race/ethnicity and specific test attributes were independently associated (P < 0.05) with test preferences.

CONCLUSIONS

Primary care patients have distinct preferences for CRC screening tests that can be linked to test attributes. Racial/ethnic variations in test preferences persist when controlling for attributes. Tailoring screening recommendations to patients' preferences may increase screening adherence.

Patients' preferences for osteoporosis drug treatment: a discrete choice experiment

Active case finding for osteoporosis is used to identify patients at high fracture risk who may benefit from preventive drug treatment. We investigated the relative weight that women place on various aspects of preventive drugs in a discrete choice experiment. Our patients said they were prepared to take preventive drugs even if side effects were expected.

INTRODUCTION

Active case finding for osteoporosis is used to identify patients who may benefit from preventive drugs. We aimed to elicit the relative weight that patients place on various aspects of preventive drug treatment for osteoporosis.

METHODS

We designed a discrete choice experiment, in which women had to choose between drug profiles that differed in five treatment attributes: effectiveness, side effects (nausea), total treatment duration, route of drug administration, and out-of-pocket costs. We included 120 women aged 60 years and older, identified by osteoporosis case finding in 34 general practices in the Netherlands. A conditional logit regression model was used to analyse the relative importance of treatment attributes, the trade-offs that women were willing to make between attributes, and their willingness to pay.

RESULTS

All treatment attributes proved to be important for women's choices. A reduction of the relative 10-year risk of hip fracture by 40% or more by the drug was considered to compensate for nausea as a side effect. Women were prepared to pay an out-of-pocket contribution for the currently available drug treatment (bisphosphonate) if the fracture risk reduction was at least 12%.

CONCLUSIONS

Women identified by active osteoporosis case finding stated to be prepared to take preventive drugs, even if side effects were expected and some out-of-pocket contribution was required.

Quality of life valuations of mammography screening

OBJECTIVE

To obtain quality-of-life (QOL) valuations associated with mammography screening and breast cancer treatment that are suitable for use in cost-effectiveness analyses.

METHODS

Subjects comprised 131 women (age range 50-79 years) randomly sampled from a breast cancer screening program. In an in-person or telephone interview, women rated the QOL impact of 14 clinical scenarios (ranging from mammography to end-of-life care for breast cancer) using a visual analogue scale anchored by death (0) and perfect health/quality of life (100).

RESULTS

Women rated the scenarios describing true negative results, false positive results, and routine screening mammography at 80 or above on a scale of 0-100, suggesting that they perceive these states as being close to perfect health. They rated adjuvant chemotherapy (39.7; range 10-90), palliation/end-of-life care (35.8; range 0-100), and recurrence at 1 year (33.0; range 0-95) the lowest, suggesting that these health states are perceived as compromised. Women rated receiving news of a breast cancer diagnosis (true positive) (45.7; range 5-100) and receiving delayed news of a breast cancer diagnosis (false negative) (48.5; range 5-100) as being comparable to undergoing mastectomy (48.3; range 10-100) and radiation therapy (46.2; range 5-100) for breast cancer.

CONCLUSIONS

These data can be used to update cost analyses of mammography screening that wish to take into account the QOL impact of screening.

Conducting discrete choice experiments to inform healthcare decision making: a user's guide

Discrete choice experiments (DCEs) are regularly used in health economics to elicit preferences for healthcare products and programmes. There is growing recognition that DCEs can provide more than information on preferences and, in particular, they have the potential to contribute more directly to outcome measurement for use in economic evaluation. Almost uniquely, DCEs could potentially contribute to outcome measurement for use in both cost-benefit and cost-utility analysis. Within this expanding remit, our intention is to provide a resource for current practitioners as well as those considering undertaking a DCE, using DCE results in a policy/commercial context, or reviewing a DCE. We present the fundamental principles and theory underlying DCEs. To aid in undertaking and assessing the quality of DCEs, we discuss the process of carrying out a choice study and have developed a checklist covering conceptualizing the choice process, selecting attributes and levels, experimental design, questionnaire design, pilot testing, sampling and sample size, data collection, coding of data, econometric analysis, validity, interpretation and welfare and policy analysis. In this fast-moving area, a number of issues remain on the research frontier. We therefore outline potentially fruitful areas for future research associated both with DCEs in general, and with health applications specifically, paying attention to how the results of DCEs can be used in economic evaluation. We also discuss emerging research trends. We conclude that if appropriately designed, implemented, analysed and interpreted, DCEs offer several advantages in the health sector, the most important of which is that they provide rich data sources for economic evaluation and decision making, allowing investigation of many types of questions, some of which otherwise would be intractable analytically. Thus, they offer viable alternatives and complements to existing methods of valuation and preference elicitation.

Measuring patient preferences for colorectal cancer screening using a choice-format survey

OBJECTIVE

Colorectal cancer (CRC) screening uptake remains poor. Until we understand patient motivation and preferences for undertaking screening, it is unlikely the uptake will be optimal. Our objective is to examine patient preferences for CRC screening modalities and uptake rates using utility-based methods.

METHODS

The preference survey was mailed to a random sample of Canadian subjects aged 40 to 60 years from a primary care network. A fractional factorial experimental design maximized D-efficiency and included four blocks with 12 choice tasks in a conditional two-step design, two-alternative discrete choice format with five screening attributes (process, pain, preparation, sensitivity, and specificity). Bivariate probit regression analysis was used to estimate patient preferences for attributes, choice probabilities for alternative modalities and expected rates of uptake.

RESULTS

Five hundred forty-seven of 1047 surveys were returned. Almost 30% of respondents preferred no screening. The most preferred test attribute levels were noninvasive process (e.g., CT), no preparation, no pain, 100% specificity, and 90% sensitivity. Accuracy-related attributes were more important than test process-related attributes. Virtual colonoscopy was the most preferred, followed by colonoscopy, barium enema, sigmoidoscopy, and fecal DNA testing, based on simulated choice probability estimates. Fecal occult blood testing (FOBT) was least preferred. Adjusted screening uptake rate estimates showed the greatest impact (42% increase) would be achieved if all CRC screening modalities were available rather than FOBT alone.

CONCLUSIONS

Our findings emphasize the important role of patient preferences for no screening and in selecting alternative CRC screening modalities. CRC screening implementation in Canada should consider patient preferences to optimize uptake.

Impact of improvement in specificity of primary screening test on total cost of prostate cancer mass screening

OBJECTIVES

Improvement in the specificity of primary screening tests, without significant cost elevation of the assay, provides cost savings in prostate cancer screening programs by reducing unnecessary secondary screening procedures. The purpose of this study was to evaluate the economic impact of improvement in the specificity of primary screening tests and to estimate the socially acceptable cost elevation for improved specificity.

METHODS

A decision-analytic model was designed to evaluate the total costs of prostate cancer mass screening according to the changes in the specificity and the cost of the primary screening test. All assumed factors were tested by three-way sensitivity analyses incorporating cost and specificity.

RESULTS

The base case analysis showed that a 1% improvement in the specificity of the primary screening test provides a $1.19 cost reduction per participant. Sensitivity analyses showed that an acceptable cost elevation for a 1% improvement in the specificity ranged from 0.68 to 2.90 $/% with respect to changes in several factors in the screening program.

CONCLUSIONS

The specificity and cost of the primary screening test has a significant economical impact on prostate cancer mass screening. For each screening program, it should be taken into consideration whether the cost of the new test deserves the specificity.

Principe, intérêts et limites de la méthode des choix discrets pour la révélation des préférences en santé

Patients play an increasingly active role in the medical decision making process. Hence, methods for eliciting public preferences have become essential tools for enlightening the choices of health authorities. Discrete choice modelling is the most recently applied technique in the field of health. This article deals with the principle, the strengths and the weaknesses of this method. Often used in English-speaking countries, the discrete choice method has several advantages over other elicitation methods since it allows estimation of marginal utilities. Compliance rates are also higher and more information is provided. Considering these qualities, further research should be undertaken on discrete choice modelling in France.