Comparing Discrete Choice Experiment with Swing Weighting to Estimate Attribute Relative Importance: A Case Study in Lung Cancer Patient Preferences

INTRODUCTION

Discrete choice experiments (DCE) are commonly used to elicit patient preferences and to determine the relative importance of attributes but can be complex and costly to administer. Simpler methods that measure relative importance exist, such as swing weighting with direct rating (SW-DR), but there is little empirical evidence comparing the two. This study aimed to directly compare attribute relative importance rankings and weights elicited using a DCE and SW-DR.

METHODS

A total of 307 patients with non-small-cell lung cancer in Italy and Belgium completed an online survey assessing preferences for cancer treatment using DCE and SW-DR. The relative importance of the attributes was determined using a random parameter logit model for the DCE and rank order centroid method (ROC) for SW-DR. Differences in relative importance ranking and weights between the methods were assessed using Cohen's weighted kappa and Dirichlet regression. Feedback on ease of understanding and answering the 2 tasks was also collected.

RESULTS

Most respondents (>65%) found both tasks (very) easy to understand and answer. The same attribute, survival, was ranked most important irrespective of the methods applied. The overall ranking of the attributes on an aggregate level differed significantly between DCE and SW-ROC (P < 0.01). Greater differences in attribute weights between attributes were reported in DCE compared with SW-DR (P < 0.01). Agreement between the individual-level attribute ranking across methods was moderate (weighted Kappa 0.53-0.55).

CONCLUSION

Significant differences in attribute importance between DCE and SW-DR were found. Respondents reported both methods being relatively easy to understand and answer. Further studies confirming these findings are warranted. Such studies will help to provide accurate guidance for methods selection when studying relative attribute importance across a wide array of preference-relevant decisions.

HIGHLIGHTS

Both DCEs and SW tasks can be used to determine attribute relative importance rankings and weights; however, little evidence exists empirically comparing these methods in terms of outcomes or respondent usability.Most respondents found the DCE and SW tasks very easy or easy to understand and answer.A direct comparison of DCE and SW found significant differences in attribute importance rankings and weights as well as a greater spread in the DCE-derived attribute relative importance weights.

Can the General Public Be a Proxy for an "At-Risk" Group in a Patient Preference Study? A Disease Prevention Example in Rheumatoid Arthritis

BACKGROUND

When selecting samples for patient preference studies, it may be difficult or impractical to recruit participants who are eligible for a particular treatment decision. However, a general public sample may not be an appropriate proxy.

OBJECTIVE

This study compares preferences for rheumatoid arthritis (RA) preventive treatments between members of the general public and first-degree relatives (FDRs) of confirmed RA patients to assess whether a sample of the general public can be used as a proxy for FDRs.

METHODS

Participants were asked to imagine they were experiencing arthralgia and had screening tests indicating a 60% chance of developing RA within 2 yrs. Using a discrete choice experiment, participants were offered a series of choices between no treatment and 2 unlabeled hypothetical treatments to reduce the risk of RA. To assess data quality, time to complete survey sections and comprehension questions were assessed. A random parameter logit model was used to obtain attribute-level estimates, which were used to calculate relative importance, maximum acceptable risk (MAR), and market shares of hypothetical preventive treatments.

RESULTS

The FDR sample (n = 298) spent more time completing the survey and performed better on comprehension questions compared with the general public sample (n = 982). The relative importance ranking was similar between the general public and FDR participant samples; however, other relative preference measures involving weights including MARs and market share differed between groups, with FDRs having numerically higher MARs.

CONCLUSION

In the context of RA prevention, the general public (average risk) may be a reasonable proxy for a more at-risk sample (FDRs) for overall relative importance ranking but not weights. The rationale for a proxy sample should be clearly justified.

HIGHLIGHTS

Participants from the general public were compared to first-degree relatives on their preferences for rheumatoid arthritis (RA) preventive treatments using a discrete choice experiment.Preferences were similar between groups in terms of the most important and least important attributes of preventive treatments, with effectiveness being the most important attribute. However, relative weights differed.Attention to the survey and predicted market shares of hypothetical RA preventive treatments differed between the general public and first-degree relatives.The general public may be a reasonable proxy for an at-risk group for patient preferences ranks but not weights in the disease prevention context; however, care should be taken in sample selection for patient preference studies when choosing nonpatients.

Precision cancer medicine and the doctor-patient relationship: a systematic review and narrative synthesis

BACKGROUND

The implementation of precision medicine is likely to have a huge impact on clinical cancer care, while the doctor-patient relationship is a crucial aspect of cancer care that needs to be preserved. This systematic review aimed to map out perceptions and concerns regarding how the implementation of precision medicine will impact the doctor-patient relationship in cancer care so that threats against the doctor-patient relationship can be addressed.

METHODS

Electronic databases (Pubmed, Scopus, Web of Science, Social Science Premium Collection) were searched for articles published from January 2010 to December 2021, including qualitative, quantitative, and theoretical methods. Two reviewers completed title and abstract screening, full-text screening, and data extraction. Findings were summarized and explained using narrative synthesis.

RESULTS

Four themes were generated from the included articles (n = 35). Providing information addresses issues of information transmission and needs, and of complex concepts such as genetics and uncertainty. Making decisions in a trustful relationship addresses opacity issues, the role of trust, and and physicians' attitude towards the role of precision medicine tools in decision-making. Managing negative reactions of non-eligible patients addresses patients' unmet expectations of precision medicine. Conflicting roles in the blurry line between clinic and research addresses issues stemming from physicians' double role as doctors and researchers.

CONCLUSIONS

Many findings have previously been addressed in doctor-patient communication and clinical genetics. However, precision medicine adds complexity to these fields and further emphasizes the importance of clear communication on specific themes like the distinction between genomic and gene expression and patients' expectations about access, eligibility, effectiveness, and side effects of targeted therapies.

Exploring preferences of at-risk individuals for preventive treatments for rheumatoid arthritis

OBJECTIVE

Some immunomodulatory drugs have been shown to delay the onset of, or lower the risk of developing, rheumatoid arthritis (RA), if given to individuals at risk. Several trials are ongoing in this area; however, little evidence is currently available about the views of those at risk of RA regarding preventive treatment.

METHOD

Three focus groups and three interviews explored factors that are relevant to first degree relatives (FDRs) of RA patients and members of the general public when considering taking preventive treatment for RA. The semi-structured qualitative interview prompts explored participant responses to hypothetical attributes of preventive RA medicines. Transcripts of focus group/interview proceedings were inductively coded and analysed using a framework approach.

RESULTS

Twenty-one individuals (five FDRs, 16 members of the general public) took part in the study. Ten broad themes were identified describing factors that participants felt would influence their decisions about whether to take preventive treatment if they were at increased risk of RA. These related either directly to features of the specific treatment or to other factors, including personal characteristics, attitude towards taking medication, and an individual's actual risk of developing RA.

CONCLUSION

This research highlights the importance of non-treatment factors in the decision-making process around preventive treatments, and will inform recruitment to clinical trials as well as information to support shared decision making by those considering preventive treatment. Studies of treatment preferences in individuals with a confirmed high risk of RA would further inform clinical trial design.

Public Preferences for Introducing a COVID-19 Certificate: A Discrete Choice Experiment in the Netherlands

OBJECTIVE

Here we investigate public preferences for coronavirus disease 2019 (COVID-19) certificates in the Netherlands, and whether these preferences differ between subgroups in the population.

METHODS

A survey including a discrete choice experiment was administered to 1500 members of the adult population of the Netherlands. Each participant was asked to choose between hypothetical COVID-19 certificates that differed in seven attributes: the starting date, and whether the certificate allowed gathering with multiple people, shopping without appointment, visiting bars and restaurants, visiting cinemas and theatres, attending events, and practising indoor sports. Latent class models (LCMs) were used to determine the attribute relative importance and predicted acceptance rate of hypothetical certificates.

RESULTS

Three classes of preference patterns were identified in the LCM. One class a priori opposed a certificate (only two attributes influencing preferences), another class was relatively neutral and included all attributes in their decision making, and the final class was positive towards a certificate. Respondents aged > 65 years and those who plan to get vaccinated were more likely to belong to the latter two classes. Being allowed to shop without appointment and to visit bars and restaurants was most important to all respondents, increasing predicted acceptance rate by 12 percentage points.

CONCLUSIONS

Preferences for introduction of a COVID-19 certificate are mixed. A certificate that allows for shopping without appointment and visiting bars and restaurants is likely to increase acceptance. The support of younger citizens and those who plan to get vaccinated seems most sensitive to the specific freedoms granted by a COVID-19 certificate.

POS0591 TREATMENTS TO PREVENT RHEUMATOID ARTHRITIS IN FIRST DEGREE RELATIVES: DEMOGRAPHIC AND PSYCHOLOGICAL PREDICTORS OF RISK TOLERANCES

Background

There is a growing research focus on the development of interventions to reduce risk of rheumatoid arthritis (RA) in at-risk groups.(1) RA patients’ first-degree relatives (FDRs) have an elevated risk of developing RA and are potential candidates for preventive interventions. Recent studies have quantified the preferences of at risk groups for preventive treatments.(2-4) Little is known about predictors of preference heterogeneity in this context.

Objectives

Assess the extent to which FDR characteristics and beliefs predict risk tolerances for preventive treatments.

Methods

Adult FDRs of patients with confirmed RA in the UK were invited to take part in a web-based survey. FDRs enrolled in a UK prospective cohort (PREVeNT-RA) were also invited. Survey development, including attribute selection and presentation, was informed by qualitative research, ranking surveys, literature review, and expert opinion including patient research partners. Respondents received information about RA, questions to check comprehension, and an introduction to the survey. Participants were asked to imagine they were experiencing arthralgia and had positive autoantibody tests indicating a 60% chance of developing RA within two years. Using a probabilistic threshold technique, participants made choices between no treatment (no benefit and no risks) or a preventive treatment option. Treatment options were defined by a fixed level of benefit (reduction in risk of RA from 60% to 20%) and varying levels of risks (Table 1). For each treatment risk, participants made a series of choices where the risk was systematically increased or decreased until they switched their choice. This procedure was repeated for each of the remaining risks. Participants also completed items assessing demographics, perceived risk of developing RA, health literacy, subjective numeracy, the Brief Illness Perception Questionnaire (IPQ) and the Beliefs about Medicines Questionnaire General (BMQ-G). The maximum acceptable risk (MAR) respondents were willing to accept for a 40% (60% to 20%) point risk reduction in developing RA was summarized across participants using descriptive statistics. Associations between MARs and participants’ characteristics and illness/medication beliefs were assessed using interval regression. Independent variables were dichotomized and effects coded.

Table 1.

Attributes and levels of treatment options

Treatment attributeLevels describing no treatment optionLevels describing treatment optionChance of developing RA60%20%Chance of mild side effects0%2%; 4%; 5%; 7% or 10%Chance of a serious infection due to treatment0%1%; 1.5%; 2%; 3% or 5%Chance of a serious side effect that is potentially irreversible0%0.001%; 0.01%; 0.02%; 0.05% or 0.1%

Results

289 FDRs (80 male) responded. The mean (SE) MAR for mild side effects, serious infection, and serious side effects was 29.08 (1.52), 9.09 (0.60) and 0.85 (0.27), respectively. Participants aged over 60 years were less tolerant of risk of serious infection than average (mean MAR - 2.06 (0.78)) and younger participants were more tolerant of risk of serious infection than average (mean MAR + 2.06 (0.78)). Risk of mild side effects was less acceptable to participants who perceived they were likely/very likely to develop RA (mean MAR - 3.34 (1.55)) than to those who did not (mean MAR + 3.34 (1.55)). Education level, health literacy, numeracy, IPQ and BMQ-G subscales were not predictors of risk tolerance.

Conclusion

Age and perceived risk of RA had a significant impact on FDRs’ tolerance for specific, but not all, included risks. Cognitive ability and beliefs about RA/medicine did not explain preference heterogeneity. This is informative for drug development and the development of tailored risk communication resources to support preventive approaches.

References

[1]Mankia et al. Ann Rheum Dis. 2021;80(10):1286-98.

[2]Simons et al. Ann Rheum Dis. 2021;80:96-7.

[3]Harrison et al. Plos One. 2009; 14(4): e0216075.

[4]Finckh et al. Curr Rheumatol Rep. 2016;18: 51.

Acknowledgements

On behalf of the PREFER project. PREFER received funding from the IMI 2 Joint Undertaking (grant No. 115966), which receives support from the EU’s Horizon 2020 research and innovation program and European Federation of Pharmaceutical Industries and Associations (EFPIA). K. Raza is supported by the NIHR Birmingham Biomedical Research Centre.

Disclosure of Interests

Gwenda Simons: None declared, Ellen Janssen Shareholder of: Johnson & Johnson, Employee of: Janssen Research and Development, Jorien Veldwijk: None declared, Rachael DiSantostefano Shareholder of: Johnson & Johnson, Employee of: Janssen Research and Development, Matthias Englbrecht Speakers bureau: Abbvie, Chugai, Eli Lilly, Novartis, Roche, Sanofi, Mundipharma, Paid instructor for: Abbvie, Chugai, Roche, Consultant of: Abbvie, Novartis, Roche, Sanofi, Grant/research support from: Roche, Chugai, Christine Radawski Shareholder of: Eli Lilly, Employee of: Eli Lilly, Larissa Valor: None declared, Jenny Humphreys: None declared, Ian N. Bruce: None declared, Brett Hauber Shareholder of: Pfizer Inc., Employee of: Pfizer Inc., Karim Raza Consultant of: Abbvie, Sanofi, Grant/research support from: Bristol Myers Squibb, Marie Falahee: None declared.

OP0276 PREFERENCES FOR TREATMENTS TO PREVENT RHEUMATOID ARTHRITIS: DISCRETE CHOICE SURVEY OF RHEUMATOID ARTHRITIS PATIENTS’ FIRST-DEGREE RELATIVES IN THE UNITED KINGDOM AND GERMANY

Background

There is a growing research focus on the development of interventions to reduce risk of rheumatoid arthritis (RA) in at-risk individuals.(1) A recent survey of the general population asked to assume a 60% risk of RA established that hypothetical preventive treatments were acceptable to most participants.(2) However the preferences of individuals who actually have an elevated risk of RA, such as first-degree relatives (FDRs) of RA patients, are not well understood.

Objectives

To quantify FDRs’ preferences for preventive treatments for RA.

Methods

Adult FDRs in the UK and Germany were invited to take part in a web-based survey via patients with clinician-confirmed RA either during a rheumatology clinic visit or by mail. In addition, FDRs taking part in a UK-based prospective cohort (PREVeNT-RA) were invited via email. Participants received information about RA followed by questions to check comprehension, and an introduction to the survey including warm-up questions. They were asked to imagine they were experiencing arthralgia and had positive autoantibody tests indicating a 60% chance of developing RA in the next two years. Using a discrete choice experiment, participants were offered a series of 15 choices between no treatment and two unlabeled hypothetical treatments to reduce risk of RA. Treatments were defined by six attributes with varying levels, describing benefits, risks, and frequency/route of administration (Table 1). Attribute selection and presentation was informed by qualitative research, ranking surveys, systematic literature review, and expert opinion. Survey layout was informed by patient research partners and qualitative pre-testing. A two-class latent class analysis was used to estimate preferences and calculate relative importance of treatment attributes and predicted uptake. A panel mixed logit model was used to obtain maximum acceptable risk estimates.

Table 1.

Treatment attributes and levels

AttributeLevelsChance of developing RA reduced from 60% to10%; 20%; 30%; 40%How the treatment is takenA shallow injection under the skinA drip into the veinOne or two tabletsHow often the medication has to be takenDailyWeeklyMonthlyEvery 6 monthsChance of mild side effects2%; 5%; 10%Chance of a serious infection due to treatment0%; 1%; 5%Chance of a serious side effect that is potentially irreversible1 in 100,000 people20 in 100,000 people100 in 100,000 people

Results

356 FDRs (252 female, 289 in the UK) responded. While treatment effectiveness was the most important attribute in both classes (Figure 1), the importance of other attributes differed between classes, with method and frequency of treatment administration being more important in class 2 and risk of mild side effects only impacting treatment choice in class 1. Perceived risk of developing RA predicted class assignment; those with higher perceived risk were more likely to belong to class 1. On average, the predicted uptake of treatment profiles estimating prevention candidates: abatacept; atorvastatin; hydroxychloroquine; tolerogenic cell-based therapy; and no treatment would be 50%, 15%, 9%, 18% and 0%, respectively. Finally, the maximum acceptable risk participants were willing to accept were 81%, 25% and 3% point increases in risk of mild side effects, serious infection, and serious side effects, respectively, for medicines that would reduce their risk of developing RA in the upcoming two years from 60% to 20%.

Conclusion

Effective preventive treatments for RA were acceptable to FDRs asked to assume a 60% chance of developing RA. Mode and frequency of treatment administration had a greater impact on treatment choices for participants with a lower perceived risk of RA. These findings are informative for target product profile development, endpoint selection, benefit-risk assessment, regulatory approval, and development of informational resources for those at risk of RA.

References

[1]Mankia et al. Ann Rheum Dis. 2021;80(10):1286-98.

[2]Simons et al. Ann Rheum Dis. 2021;80:96-7.

Acknowledgements

On behalf of the PREFER project. PREFER received funding from the IMI 2 Joint Undertaking (grant No. 115966), which receives support from the EU’s Horizon 2020 research and innovation program and European Federation of Pharmaceutical Industries and Associations (EFPIA). This abstract and its contents reflect the view of the presenter and not the view of PREFER, IMI, the European Union or EFPIA. K. Raza is supported by the NIHR Birmingham Biomedical Research Centre.

Disclosure of Interests

Gwenda Simons: None declared, Jorien Veldwijk: None declared, Rachael DiSantostefano Shareholder of: Johnson & Johnson, Employee of: Janssen Research and Development, Matthias Englbrecht Speakers bureau: Abbvie, Chugai, Eli Lilly, Novartis, Roche, Sanofi, Munidpharma, Paid instructor for: Abbvie, Chugai, Roche, Consultant of: Abbvie, Novartis, Roche, Sanofi, Grant/research support from: Roche, Chugai, Christine Radawski Shareholder of: Eli Lilly & Company, Employee of: Eli Lilly & Company, Larissa Valor: None declared, Jenny Humphreys: None declared, Ian N. Bruce: None declared, Karim Raza Consultant of: Abbvie, Sanofi, Grant/research support from: Bristol Myers Squibb, Marie Falahee: None declared

OP0160-HPR PREFERENCES FOR TREATMENTS TO PREVENT RHEUMATOID ARTHRITIS: DISCRETE CHOICE SURVEY OF GENERAL POPULATIONS IN UNITED KINGDOM, GERMANY, AND ROMANIA

Background:

There is increasing research focus on intervention for rheumatoid arthritis (RA) at the earliest stages of disease development, including treatment to prevent RA in at-risk groups. Novel cellular therapies are in development, and the effectiveness of existing immunomodulatory agents to prevent RA in those at risk is under investigation. Quantitative evidence of likely uptake of preventive treatments, and preferences for benefits and risks of such treatments is limited.

Objectives:

To quantify preferences for preventive therapies for RA.

Methods:

A web-based survey (n = 2959) was administered to an age- and gender- stratified sample of adults in the general population from online survey panels in the UK, Germany, and Romania. After receiving information about RA, questions to check comprehension of background information, an introduction to the survey tasks and warm-up questions, participants were asked to imagine that they were experiencing arthralgia (without swelling) and had positive autoantibody tests indicating a 60% chance of developing RA in the next two years. Using a discrete choice experiment with a Bayesian D-efficient design, participants were offered a series of 15 choices between no treatment and two unlabeled hypothetical treatments to lower risk of RA development. Treatments were defined by six attributes with varying levels including benefits, risks, and frequency/route of administration (Table 1). One choice task with fixed levels described treatments representative of those under investigation for RA prevention (abatacept, hydroxychloroquine, atorvastatin and tolerogenic cell-based therapy). Attribute selection and presentation was informed by previous qualitative research, ranking surveys, systematic literature review, and expert opinion. Survey design was informed by patient research partners. The survey was pre-tested during qualitative interviews and revised. A pilot of the final survey with 100 respondents was conducted to obtain priors for the final experimental design. Random parameters logit (RPL) models were used to estimate relative importance of treatment attributes and likely treatment uptake rates in each country.

Table 1.

Treatment attributes and levels

AttributeLevelsChance of developing RA reduced from 60% to10%; 20%; 30%; 40%How the treatment is takenA shallow injection under the skinA drip into the veinOne or two tabletsHow often the medication has to be takenDailyWeeklyMonthlyEvery 6 monthsChance of mild side effects2%; 5%; 10%Chance of a serious infection due to treatment0%; 1%; 5%Chance of a serious side effect that is potentially irreversible1 in 100,000 people20 in 100,000 people100 in 100,000 people

Results:

Across all three countries, effectiveness was the treatment attribute that had most impact on treatment choice (Figure 1). Method of administration was second most important for respondents from the UK and Romania but less important for German respondents. Risks of serious infection and serious side effects were more important determinants of treatment choice for respondents in Romania than they were in the UK and Germany. Percentage choice of fixed profiles reflecting abatacept, atorvastatin, hydroxychloroquine, tolerogenic cell-based therapy and no treatment differed across countries (χ2=78.90; p<0.001): 28.3%, 20.6%, 22.2% 18.5% and 10.4% respectively in the UK; 31.3%, 18.8%, 11.2%, 23.4% and 15.3% in Germany; and 27.6%, 20.5%, 15.8%, 21.7% and 14.4% in Romania.

Conclusion:

This study suggests that effective preventive treatments for RA are acceptable to members of the general population told to assume up a 60% chance of developing RA. The relative importance of treatment attributes and likely uptake of fixed treatment profiles differed across countries. These findings are informative for the design of prevention trials, and the development of informational resources and efficient preventive strategies for those at risk of developing RA.

Acknowledgements:

On behalf of the PREFER project. PREFER received funding from the IMI 2 Joint Undertaking (grant No. 115966), which receives support from the EU’s Horizon 2020 research and innovation program and European Federation of Pharmaceutical Industries and Associations (EFPIA). K. Raza is supported by the NIHR Birmingham Biomedical Research Centre.

Disclosure of Interests:

Gwenda Simons: None declared, Jorien Veldwijk: None declared, Rachael Di Santostefano Shareholder of: Johnson & Johnson, Employee of: Janssen R&D (of Johnson & Johnson), Matthias Englbrecht Speakers bureau: AbbVie, Chugai, Eli Lilly, Novartis, Roche, Sanofi, Mundipharma, Paid instructor for: AbbVie, Chugai, Roche, Consultant of: AbbVie, Novartis, Roche, Sanofi, Grant/research support from: Roche, Chugai, Christine Radawski Shareholder of: Eli Lilly & Company, Employee of: Eli Lilly & Company, Larissa Valor: None declared, Karim Raza Consultant of: Personal fees from Abbvie, Pfizer, Sanofi, Lilly, Bristol Myers Squibb, UCB, Janssen, and Roche Chugai, Grant/research support from: Abbvie and Pfizer, M. Falahee: None declared

Preferences regarding antibiotic treatment and the role of antibiotic resistance: A discrete choice experiment

OBJECTIVES

To identify preferences of the Swedish public regarding antibiotic treatment characteristics and the relative weight of antibiotic resistance in their treatment choices.

METHODS

A questionnaire including a discrete choice experiment questionnaire was answered by 378 Swedish participants. Preferences of the general public regarding five treatment characteristics (attributes) were measured: contribution to antibiotic resistance, cost, side effects, failure rate and treatment duration. Latent class analysis models were used to determine attribute-level estimates and heterogeneity in preferences. Relative importance of the attributes and willingness to pay for antibiotics with a lower contribution to antibiotic resistance were calculated from the estimates.

RESULTS

All attributes influenced participants' preferences for antibiotic treatment. For the majority of participants, contribution to antibiotic resistance was the most important attribute. Younger respondents found contribution to antibiotic resistance more important in their choice of antibiotic treatments. Choices of respondents with lower numeracy, higher health literacy and higher financial vulnerability were influenced more by the cost of the antibiotic treatment. Older respondents with lower financial vulnerability and health literacy, and higher numeracy found side effects to be most important.

CONCLUSIONS

All attributes can be considered as potential drivers of antibiotic use by lay people. Findings also suggest that the behaviour of lay people may be influenced by concerns over the rise of antibiotic resistance. Therefore, stressing individual responsibility for antibiotic resistance in clinical and societal communication has the potential to affect personal decision making.

Can healthcare choice be predicted using stated preference data?

Lack of evidence about the external validity of Discrete Choice Experiments (DCEs)-sourced preferences inhibits greater use of DCEs in healthcare decision-making. This study examines the external validity of such preferences, unravels its determinants, and provides evidence of whether healthcare choice is predictable. We focused on influenza vaccination and used a six-step approach: i) literature study, ii) expert interviews, iii) focus groups, iv) survey including a DCE, v) field data, and vi) in-depth interviews with respondents who showed discordance between stated choices and actual healthcare utilization. Respondents without missing values in the survey and the actual healthcare utilization (377/499 = 76%) were included in the analyses. Random-utility-maximization and random-regret-minimization models were used to analyze the DCE data, whereas the in-depth interviews combined five scientific theories to explain discordance. When models took into account both scale and preference heterogeneity, real-world choices to opt for influenza vaccination were correctly predicted by DCE at an aggregate level, and 91% of choices were correctly predicted at an individual level. There was 13% (49/377) discordance between stated choices and actual healthcare utilization. In-depth interviews showed that several dimensions played a role in clarifying this discordance: attitude, social support, action of planning, barriers, and intention. Evidence was found that our DCE yields accurate actual healthcare choice predictions if at least scale and preference heterogeneity are taken into account. Analysis of discordant subjects showed that we can even do better. The DCE measures an important part of preferences by focusing on attribute tradeoffs that people make in their decision to participate in a healthcare intervention. Inhibitors may be among these attributes, but it is more likely that inhibitors have to do with exogenous factors like goals, religion, and social norms. Con-ducting upfront work on constraints/inhibitors of the focal behavior, not just what promotes the behavior, might further improve predictive ability.

Exploring research participants' perceptions of cardiovascular risk information-Room for improvement and empowerment

OBJECTIVE

The objective of this study was to explore research participants' (adults, age 50-65) perceptions of receiving cardiovascular risk information.

METHODS

Five focus group interviews (N = 31) were performed with research participants aged 50-65 who participated in the Swedish CArdioPulmonary BioImage Study (SCAPIS). The interviews were analyzed using qualitative content analysis.

RESULTS

The categories; the complexity of cardiovascular risk; insufficient presentation of test result; emotional responses; and health examinations provides confirmation, emerged. The test results were written in medical terms and lacked recommendations for further action which made it difficult for lay people to understand and use, and for some, also caused unnecessary worry.

CONCLUSION

There was inadequate guidance concerning the implications of the test results, especially for participants without clinical findings. In order to allow research participants to obtain better cognitive and behavioral control, improvements are needed with regard to how personal risk information is communicated in research projects connected to health services.

PRACTICAL IMPLICATIONS

The participants largely relied on physical signs when assessing their own cardiovascular risk. Health examinations are crucial for helping to add nuance to individuals' risk perceptions. For personal health information to have any real value for individuals, it must be designed from a user perspective.