Eliciting patients' preferences for epilepsy diagnostics: a discrete choice experiment

Developing feasible person-centred care alternatives to emergency department responses for adults with epilepsy: a discrete choice analysis mixed-methods study

Background

Calls have been made for paramedics to have some form of care pathway that they could use to safely divert adults with epilepsy away from emergency departments and instigate ambulatory care improvements. Different configurations are possible. To know which to prioritise for implementation/evaluation, there is a need to determine which are acceptable to service users and likely National Health Service-feasible.

Objective(s)

(1) Identify configurations being considered, (2) understand service users' views of them and current provision, (3) identify what sort of care service users want and (4) determine which configuration(s) is considered to achieve optimal balance in meeting users' preference and being National Health Service-feasible.

Design

Service providers were surveyed to address objective 1. Interviews with service users addressed objective 2. Objective 3 was addressed by completing discrete choice experiments. These determined users' care preferences for different seizure scenarios. Objective 4 was addressed by completing 'knowledge exchange' workshops. At these, stakeholders considered the findings on users' stated preferences and judged different pathway configurations against Michie's 'acceptability, practicability, effectiveness, affordability, side-effects and equity' feasibility criteria.

Setting

This project took place in England. The survey recruited representatives from neurology and neuroscience centres and from urgent and emergency care providers. For the interviews, recruitment occurred via third-sector support groups. Recruitment for discrete choice experiments occurred via the North West Ambulance Service NHS Trust and public advert. Workshop participants were recruited from neurology and neuroscience centres, urgent and emergency care providers, support groups and commissioning networks.

Participants

Seventy-two services completed the survey. Interviews were conducted with 25 adults with epilepsy (and 5 relatives) who had emergency service contact in the prior 12 months. Discrete choice experiments were completed by 427 adults with epilepsy (and 167 relatives) who had ambulance service contact in the prior 12 months. Workshops were completed with 27 stakeholders.

Results

The survey identified a range of pathway configurations. They differed in where they would take the patient and their potential to instigate ambulatory care improvements. Users had been rarely consulted in designing them. The discrete choice experiments found that users want a configuration of care markedly different to that offered. Across the seizure scenarios, users wanted their paramedic to have access to their medical records; for an epilepsy specialist (e.g. an epilepsy nurse, neurologist) to be available to advise; for their general practitioner to receive a report; for the incident to generate an appointment with an epilepsy specialist; for the care episode to last < 6 hours; and there was a pattern of preference to avoid conveyance to emergency departments and stay where they were. Stakeholders judged this configuration to be National Health Service-feasible within 5-10 years, with some elements being immediately deployable.

Limitations

The discrete choice experiment sample was broadly representative, but those reporting recent contact with an epilepsy specialist were over-represented.

Conclusions

Users state they want a configuration of care that is markedly different to current provision. The configuration they prefer was, with support and investment, judged to likely be National Health Service-feasible. The preferred configuration should now be developed and evaluated to determine its actual deliverability and efficacy.

Study registration

The study is registered as researchregistry4723.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme (NIHR award ref: 17/05/62) and is published in full in Health and Social Care Delivery Research; Vol. 12, No. 24. See the NIHR Funding and Awards website for further award information.

Developing an alternative care pathway for emergency ambulance responses for adults with epilepsy: A Discrete Choice Experiment to understand which configuration service users prefer. Part of the COLLABORATE project

INTRODUCTION

To identify service users' preferences for an alternative care pathway for adults with epilepsy presenting to the ambulance service.

METHODS

Extensive formative work (qualitative, survey and knowledge exchange) informed the design of a stated preference discrete choice experiment (DCE). This hypothetical survey was hosted online and consisted of 12 binary choices of alternative care pathways described in terms of: the paramedic's access to medical records/ 'care plan', what happens next (described in terms of conveyance), time, availability of epilepsy specialists today, general practitioner (GP) notification and future contact with epilepsy specialists. DCE scenarios were described as: (i) typical seizure at home. (ii) typical seizure in public, (iii) atypical seizure. Respondents were recruited by a regional English ambulance service and by national public adverts. Participants were randomised to complete 2 of the 3 DCEs.

RESULTS

People with epilepsy (PWE; n = 427) and friends/family (n = 167) who completed the survey were representative of the target population. PWE preferred paramedics to have access to medical records, non-conveyance, to avoid lengthy episodes of care, availability of epilepsy specialists today, GP notification, and contact with epilepsy specialists within 2-3 weeks. Significant others (close family members or friends) preferred PWE experiencing an atypical seizure to be conveyed to an Urgent Treatment Centre and preferred shorter times. Optimal configuration of services from service users' perspective far out ranked current practice (rank 230/288 possible configurations).

DISCUSSION

Preferences differ to current practice but have minimal variation by seizure type or stakeholder. Further work on feasibility of these pathways in England, and potentially beyond, is required.

Identification of Relevant Attributes for Liver Cancer Therapies (IRALCT): a maximum-difference-scaling analysis

The Identification of Relevant Attributes for Liver Cancer Therapies (IRALCT) project is intended to provide new insights into the relevant utility attributes regarding therapy choices for malignant primary and secondary liver tumors from the perspective of those who are involved in the decision-making process. It addresses the potential value of taking patients' expectations and preferences into account during the decision-making and, when possible, adapting therapies according to these preferences. Specifically, it is intended to identify the relevant clinical attributes that influence the patients', medical laymen's, and medical professionals' decisions and compare the three groups' preferences. We conducted maximum difference (MaxDiff) scaling among 261 participants (75 physicians, 97 patients with hepatic malignancies, and 89 medical laymen) to rank the importance of 14 attributes previously identified through a literature review. We evaluated the MaxDiff data using count analysis and hierarchical Bayes estimation (HB). Physicians, patients, and medical laymen assessed the same 7 attributes as the most important: probability (certainty) of a complete removal of the tumor, probability of reoccurrence of the disease, pathological evidence of tumor removal, possible complications during the medical intervention, welfare after the medical intervention, duration and intensity of the pain, and degree of difficulty of the medical intervention. The cumulative relative importance of these 7 attributes was 88.3%. Our results show that the physicians', patients', and medical laymen's preferences were very similar and stable.Trial registration DRKS-ID of the study: DRKS00013304, Date of Registration in DRKS: 2017/11/16.

Key Drivers and Facilitators of the Choice to Use mHealth Technology in People With Neurological Conditions: Observational Study

Background

There is increasing interest in the potential uses of mobile health (mHealth) technologies, such as wearable biosensors, as supplements for the care of people with neurological conditions. However, adherence is low, especially over long periods. If people are to benefit from these resources, we need a better long-term understanding of what influences patient engagement. Previous research suggests that engagement is moderated by several barriers and facilitators, but their relative importance is unknown.

Objective

To determine preferences and the relative importance of user-generated factors influencing engagement with mHealth technologies for 2 common neurological conditions with a relapsing-remitting course: multiple sclerosis (MS) and epilepsy.

Methods

In a discrete choice experiment, people with a diagnosis of MS (n=141) or epilepsy (n=175) were asked to select their preferred technology from a series of 8 vignettes with 4 characteristics: privacy, clinical support, established benefit, and device accuracy; each of these characteristics was greater or lower in each vignette. These characteristics had previously been emphasized by people with MS and or epilepsy as influencing engagement with technology. Mixed multinomial logistic regression models were used to establish which characteristics were most likely to affect engagement. Subgroup analyses explored the effects of demographic factors (such as age, gender, and education), acceptance of and familiarity with mobile technology, neurological diagnosis (MS or epilepsy), and symptoms that could influence motivation (such as depression).

Results

Analysis of the responses to the discrete choice experiment validated previous qualitative findings that a higher level of privacy, greater clinical support, increased perceived benefit, and better device accuracy are important to people with a neurological condition. Accuracy was perceived as the most important factor, followed by privacy. Clinical support was the least valued of the attributes. People were prepared to trade a modest amount of accuracy to achieve an improvement in privacy, but less likely to make this compromise for other factors. The type of neurological condition (epilepsy or MS) did not influence these preferences, nor did the age, gender, or mental health status of the participants. Those who were less accepting of technology were the most concerned about privacy and those with a lower level of education were prepared to trade accuracy for more clinical support.

Conclusions

For people with neurological conditions such as epilepsy and MS, accuracy (ie, the ability to detect symptoms) is of the greatest interest. However, there are individual differences, and people who are less accepting of technology may need far greater reassurance about data privacy. People with lower levels of education value greater clinician involvement. These patient preferences should be considered when designing mHealth technologies.

Parental preferences for seizure detection devices: a discrete choice experiment

Objective

Previous studies identified essential user preferences for seizure detection devices (SDDs), without addressing their relative strength. We performed a discrete choice experiment (DCE) to quantify attributes' strength, and to identify the determinants of user SDD preferences.

Methods

We designed an online questionnaire targeting parents of children with epilepsy to define the optimal balance between SDD sensitivity and positive predictive value (PPV) while accounting for individual seizure frequency. We selected five DCE attributes from a recent study. Using a Bayesian design, we constructed 11 unique choice tasks and analyzed these using a mixed multinomial logit model.

Results

One hundred parents responded to the online questionnaire link; 49 completed all tasks, whereas 28 completed the questions, but not the DCE. Most parents preferred a relatively high sensitivity (80%–90%) over a high PPV (>50%). The preferred sensitivity‐to‐PPV ratio correlated with seizure frequency (r = −.32), with a preference for relative high sensitivity and low PPV among those with relative low seizure frequency (p = .04). All DCE attributes significantly impacted parental choices. Parents expressed preferences for consulting a neurologist before device use, personally training the device's algorithm, interaction with their child via audio and video, alarms for all seizure types, and an interface detailing measurements during an alarm. Preferences varied between subgroups (learning disability or not, SDD experience, relative low vs. high seizure frequency based on the population median).

Significance

Various attributes impact parental SDD preferences and may explain why preferences vary among users. Tailored approaches may help to meet the contrasting needs among SDD users.

Patient preferences pertaining to treatment options for drug-resistant focal epilepsy

OBJECTIVE

To determine patient acceptability of benefit-risk trade-offs in selecting treatment options for drug-resistant mesial temporal lobe epilepsy, including open brain surgery, laser ablation (laser interstitial thermal therapy [LITT]), and continued medications.

METHODS

A discrete-choice experiment survey was developed, consisting of 20 versions that were randomly assigned to respondents. Each version had 8 sets of constructed treatment alternatives, representing open brain surgery, LITT, or continued medical management. For each set, respondents indicated the treatment alternative they would choose first. Treatment alternatives were characterized by varying levels of chance of seizure freedom for at least 2 years (20-70%), risk of 30-day mortality (0-10%), and risk of neurological deficits (0-40%). Respondents' choices were analyzed using random-parameters logit models to quantify acceptable benefit-risk trade-offs. Preference heterogeneity was evaluated using latent-class analysis.

RESULTS

The survey was administered to 2 cohorts of adult patients with drug-resistant epilepsy: a Duke cohort identified using diagnostic codes (n = 106) and a web-recruited panel with a self-reported physician diagnosis of drug-resistant epilepsy (n = 300). Based on mean preference weights, respondents who indicated a willingness to consider surgical intervention would accept a reduction in chance of seizure freedom from 70% to a minimum-acceptable benefit (MAB) of 23% if they could undergo LITT rather than open brain surgery. For a reduction in 30-day mortality from 1% to 0%, MAB was 52%. For a reduction in risk of long-term deficits from 10% to 0%, MAB was 39%. Latent-class analysis revealed additional choice patterns identifying respondent groups that more strongly favored continuing medications or undergoing surgery.

CONCLUSION

Patients who are receptive to surgery would accept significantly lower treatment effectiveness to undergo a minimally invasive procedure relative to open brain surgery. They also were willing to accept lower treatment benefit to reduce risks of mortality or neurological deficits.

Relative importance of clinical outcomes and safety risks of antiseizure medication monotherapy for patients and physicians: Discrete choice experiment eliciting preferences in real-world study "VOTE"

OBJECTIVE

This study was undertaken to elicit patients' preferences for attributes characterizing antiseizure medication (ASM) monotherapy options before treatment consultation, and to explore the trade-offs patients consider between treatment efficacy and risks of side effects. Further objectives were to explore how treatment consultation may affect patient preferences, to elicit physicians' preferences in selecting treatment, and to compare patient and physician preferences for treatment.

METHODS

This prospective, observational study (EP0076; VOTE) included adults with focal seizures requiring a change in their ASM monotherapy. Patients completed a discrete choice experiment (DCE) survey before and after treatment consultation. Physicians completed a similar survey after the consultation. The DCE comprised 12 choices between two hypothetical treatments defined by seven attributes. The conditional relative importance of each attribute was calculated.

RESULTS

Three hundred ten patients (mean [SD] age = 46.8 [18.3] years, 52.3% female) were enrolled from eight European countries, of whom 305 completed the survey before consultation and 273 completed the survey before and after consultation. Overall, this preference study in patients who intended to receive a new ASM monotherapy suggests that patient preferences were ordered as expected, with better outcomes being preferred to worse outcomes; patients preferred a higher chance of seizure freedom, lower risk of developing clinical depression, and fewer severe adverse events; avoiding moderate-to-severe "trouble thinking clearly" was more important than avoiding any other side effect. There were qualitative differences in what patients and physicians considered to be the most important aspects of treatment for patients; compared with patients, physicians had a qualitatively stronger preference for greater chance of seizure freedom and avoiding personality changes. Patients' preference weights were qualitatively similar before and after treatment consultation.

SIGNIFICANCE

For patients, seizure freedom and avoiding trouble thinking clearly were the most important treatment attributes. Physicians and patients may differ in the emphasis they place on specific attributes.

Understanding Attributes that Influence Physician and Caregiver Decisions About Neurotechnology for Pediatric Drug-Resistant Epilepsy: A Formative Qualitative Study to Support the Development of a Discrete Choice Experiment

OBJECTIVE

This study reports formative qualitative research used to analyze decision making regarding neurotechnological interventions for pediatric drug-resistant epilepsy from the perspective of physicians and caregivers and the derivation of attributes for a discrete choice experiment.

METHODS

Purposive and convenience sampling was used to recruit physicians and caregivers. Physician focus group sessions were held at key national conferences in the USA and Canada. Caregivers were approached through clinics with established epilepsy surgery programs in the USA and Canada. Thematic analysis was used to identify critical features of decisions about treatment outcomes, procedural trade-offs, values, and concerns surrounding conventional and novel pediatric drug-resistant epilepsy interventions among physicians and caregivers.

RESULTS

The results highlight the presence of central attributes that are considered by both groups in decision making, such as "chances of seizure freedom", "risk", "availability of evidence", and "cost to families", as well as attributes that reflect important differences between groups. Physicians were focused on the specifics of treatment options, while caregivers thought more holistically, considering the overall well-being of their children.

DISCUSSION

The findings shaped the development of a discrete choice experiment to understand the likely uptake of different neurotechnologies. We identified differences in decision making and thus designed two discrete choice experiments to elicit preferences for pediatric drug-resistant epilepsy treatments, one aimed at clinicians and one at caregivers. The variation we observed highlights the value of seeking to understand the influences at the point of clinical decision making and incorporating this information into care.

Hospital service quality - patient preferences - a discrete choice experiment

PURPOSE

High quality healthcare is important to all patients. If healthcare is felt to be high quality, then patients will be satisfied, and the relationship between patients and healthcare providers will improve. Patient satisfaction is among the most commonly used service quality indicators; however, it is not fully known which factors influence satisfaction. Therefore, it is necessary to pay attention to the elements that affect both healthcare quality and patient satisfaction. Nowadays, several methods are used in health economics to assess patient preferences, prioritize them and help health policy makers improve services. Discrete choice experiment (DCE) is one method that is useful to elicit patient preferences regarding healthcare services. The purpose of this paper is to apply DCE and elicit patient preferences in medical centers to rank certain healthcare quality factors.

DESIGN/METHODOLOGY/APPROACH

The descriptive, analytical study used a cross-sectional questionnaire that the authors developed. In total, 12 scenarios were chosen after applying fractional factorials. The questionnaire was completed by patients who were admitted to Kerman General Teaching Hospitals, South-East Iran in 2015. Patient preferences were identified by calculating the characteristics' marginal effects and prioritizing them. The generalized estimation equation (GEE) model was used to determine attribute effects on patient preferences.

FINDINGS

In total, 167 patients completed the questionnaire. Prioritizing the attributes showed that "physical examination" was the most important attribute. Other key features included "cleanliness," "training after discharging," "medical staff attention," "waiting for admission" and "staff attitude." All attributes were statistically significant ( p<0.05) except staff behavior. No demographic characteristic was significant.

PRACTICAL IMPLICATIONS

To increase hospital patient satisfaction, health policy makers should develop programs to enhance healthcare quality and hospital safety by increasing physical examination quality and other services.

ORIGINALITY/VALUE

To estimate DCE independent variables, logistic regression models are usually used. The authors used the GEE model to estimate discrete choice experiment owing the explanatory variables' dependency.

Discrete Choice Experiments in Health Economics: Past, Present and Future

OBJECTIVES

Discrete choice experiments (DCEs) are increasingly advocated as a way to quantify preferences for health. However, increasing support does not necessarily result in increasing quality. Although specific reviews have been conducted in certain contexts, there exists no recent description of the general state of the science of health-related DCEs. The aim of this paper was to update prior reviews (1990-2012), to identify all health-related DCEs and to provide a description of trends, current practice and future challenges.

METHODS

A systematic literature review was conducted to identify health-related empirical DCEs published between 2013 and 2017. The search strategy and data extraction replicated prior reviews to allow the reporting of trends, although additional extraction fields were incorporated.

RESULTS

Of the 7877 abstracts generated, 301 studies met the inclusion criteria and underwent data extraction. In general, the total number of DCEs per year continued to increase, with broader areas of application and increased geographic scope. Studies reported using more sophisticated designs (e.g. D-efficient) with associated software (e.g. Ngene). The trend towards using more sophisticated econometric models also continued. However, many studies presented sophisticated methods with insufficient detail. Qualitative research methods continued to be a popular approach for identifying attributes and levels.

CONCLUSIONS

The use of empirical DCEs in health economics continues to grow. However, inadequate reporting of methodological details inhibits quality assessment. This may reduce decision-makers' confidence in results and their ability to act on the findings. How and when to integrate health-related DCE outcomes into decision-making remains an important area for future research.

Burden of disease of people with epilepsy during an optimized diagnostic trajectory: costs and quality of life

BACKGROUND

Diagnosing epilepsy can be lengthy and stressful, potentially leading to increased use of healthcare resources and a reduction in quality of life.

AIM

This study aims to determine cost and quality of life before and after an optimized diagnostic procedure for people suspected of having epilepsy from a societal perspective with a follow-up of 12 months. In addition, this study aims to differentiate between people diagnosed with epilepsy during the follow-up of the study and the people who are diagnosed as not having epilepsy or for whom diagnosis is still uncertain.

METHODS

A questionnaire regarding the use of healthcare resources was used accompanied by the EQ-5D-3 L. Multiple imputations by chained equations with predictive mean matching was used to account for missing data. To investigate the uncertainty of the results, non-parametric bootstrapped (1000 times) was used.

RESULTS

In total, 116 people were included in the study. Total average costs per patient made in the previous 3 months had decreased from €4594 before the optimized diagnostic trajectory to €2609 in the 12 months after the optimized diagnostic trajectory. Healthcare costs were the largest expense group (52-66%) and had decreased significantly from baseline measurement to 12 months after baseline (€2395 vs €1581). Productivity costs had decreased from €1367 to €442 per 3 months. Total annual costs were similar between people diagnosed with epilepsy during the follow-up of the study and the people who are diagnosed as not having epilepsy or for whom diagnosis is still uncertain. Quality of Life had significantly increased over the course of 12 months from 0.80 to 0.84 (Dutch tariff).

DISCUSSION

This study indicates that an optimized diagnostic trajectory has positively influenced the use of healthcare resources and the quality of life in people with epilepsy. As chronic care patients make diverse costs, future research should identify the long-term costs after an optimized diagnostic trajectory for patients with epilepsy, possibly identifying patients who are at high risk of becoming high-cost users in the future for early intervention.

A discrete-choice experiment to elicit preferences of patients with epilepsy for self-management programs

BACKGROUND

There is an increasing number of self-management programs developed for patients with epilepsy, with the goal of supporting treatment management and improving their quality of life. With the aim of increasing medication adherence and effectiveness of self-management programs, it is important to design programs that are engaging to, and align with the preferences of patients with epilepsy. This study aimed to evaluate and compare the preferences of patients with epilepsy for self-management programs in three European countries. This is the first cross-border evaluation of the preferences of patients with epilepsy in Europe for such programs.

METHODS

Using a discrete-choice experiment, patients with epilepsy from Germany, France, and the Netherlands were surveyed, and chose repetitively between two hypothetical self-management programs. These differed in the following six characteristics: i) the thematic area which would be the main focus of the program, ii) the method of interaction, iii) the source of information or provider of the program, iv) the amount of time spent on the program per week, v) the cost, and vi) whether the program would start immediately, or if there would be a delay of 3weeks before its initiation. A Bayesian efficient design was used to construct 15 choice sets, and a mixed panel logit model was used to estimate patients' preferences. Subgroup analyses were conducted according to socioeconomic status, burden of disease, and previous activation in self-management.

RESULTS

A total of 299 people with epilepsy were included in the study, with a mean age of 45.5years. Only 15% had previously made use of a self-management program, although 44.5% reported having previously heard of them. In all three countries, all attributes barring the content were significant at 10%. The cost attribute - i.e., an out-of-pocket expenditure for a program - was reported as the most important feature in each country and across subgroups (significant at 1%). This was followed by the length of program sessions per week, which ranged from 20 to 90min per week. Although there was some heterogeneity between countries and subgroups, the patients, overall, had a preference for a face-to-face meeting with a doctor. In the Netherlands, a preference for online programs and physician assistants was observed when compared with the other countries. Other attributes, including the information source - whether a program was led by a physician, another patient with epilepsy, or another combination - was also important to patients, who appear willing to trade preferences in order to gain their favored attribute level. However, 20% of the population chose consistently to not participate in any self-management program.

CONCLUSION

Given the heterogeneity of the epilepsies, preferences, and dispreferences across subgroups, our study highlights that if full account is not taken of different segmentation strategies when designing a self-management program, a large proportion of the population may not be attracted to it.

Adolescent values for immunisation programs in Australia: A discrete choice experiment

Objectives

The importance of adolescent engagement in health decisions and public health programs such as immunisation is becoming increasingly recognised. Understanding adolescent preferences and further identifying barriers and facilitators for immunisation acceptance is critical to the success of adolescent immunisation programs. This study applied a discrete choice experiment (DCE) to assess vaccination preferences in adolescents.

Methods

This study was conducted as a cross-sectional, national online survey in Australian adolescents. The DCE survey evaluated adolescent vaccination preferences. Six attributes were assessed including disease severity, target for protection, price, location of vaccination provision, potential side effects and vaccine delivery method. A mixed logit model was used to analyse DCE data.

Results

This survey was conducted between December 2014 and January 2015. Of 800 adolescents aged 15 to 19 years, stronger preferences were observed overall for: vaccination in the case of a life threatening illness (p<0.001), lower price vaccinations (p<0.001), mild but common side effects (p = 0.004), delivery via a skin patch (p<0.001) and being administered by a family practitioner (p<0.001). Participants suggested that they and their families would be willing to pay AU$394.28 (95%CI: AU$348.40 to AU$446.92) more for a vaccine targeting a life threatening illness than a mild-moderate illness, AU$37.94 (95%CI: AU$19.22 to AU$57.39) more for being vaccinated at a family practitioner clinic than a council immunisation clinic, AU$23.01 (95%CI: AU$7.12 to AU$39.24) more for common but mild and resolving side effects compared to rare but serious side effects, and AU$51.80 (95%CI: AU$30.42 to AU$73.70) more for delivery via a skin patch than injection.

Conclusions

Consideration of adolescent preferences may result in improved acceptance of, engagement in and uptake of immunisation programs targeted for this age group.

Added diagnostic value of magnetoencephalography (MEG) in patients suspected for epilepsy, where previous, extensive EEG workup was unrevealing

OBJECTIVE

To elucidate the possible additional diagnostic yield of MEG in the workup of patients with suspected epilepsy, where repeated EEGs, including sleep-recordings failed to identify abnormalities.

METHODS

Fifty-two consecutive patients with clinical suspicion of epilepsy and at least three normal EEGs, including sleep-EEG, were prospectively analyzed. The reference standard was inferred from the diagnosis obtained from the medical charts, after at least one-year follow-up. MEG (306-channel, whole-head) and simultaneous EEG (MEG-EEG) was recorded for one hour. The added sensitivity of MEG was calculated from the cases where abnormalities were seen in MEG but not EEG.

RESULTS

Twenty-two patients had the diagnosis epilepsy according to the reference standard. MEG-EEG detected abnormalities, and supported the diagnosis in nine of the 22 patients with the diagnosis epilepsy at one-year follow-up. Sensitivity of MEG-EEG was 41%. The added sensitivity of MEG was 18%. MEG-EEG was normal in 28 of the 30 patients categorized as 'not epilepsy' at one year follow-up, yielding a specificity of 93%.

CONCLUSIONS

MEG provides additional diagnostic information in patients suspected for epilepsy, where repeated EEG recordings fail to demonstrate abnormality.

SIGNIFICANCE

MEG should be included in the diagnostic workup of patients where the conventional, widely available methods are unrevealing.

Using blocked fractional factorial designs to construct discrete choice experiments for healthcare studies

Discrete choice experiments (DCEs) are increasingly used for studying and quantifying subjects preferences in a wide variety of healthcare applications. They provide a rich source of data to assess real-life decision-making processes, which involve trade-offs between desirable characteristics pertaining to health and healthcare and identification of key attributes affecting healthcare. The choice of the design for a DCE is critical because it determines which attributes' effects and their interactions are identifiable. We apply blocked fractional factorial designs to construct DCEs and address some identification issues by utilizing the known structure of blocked fractional factorial designs. Our design techniques can be applied to several situations including DCEs where attributes have different number of levels. We demonstrate our design methodology using two healthcare studies to evaluate (i) asthma patients' preferences for symptom-based outcome measures and (ii) patient preference for breast screening services. Copyright © 2016 John Wiley & Sons, Ltd.