Objectives The EQ-HWB-S (EQ Health and Wellbeing Short version) is a new generic measure of health, social care and carer related quality of life, specifically developed to generate utility values. However, its nine dimensions pose a challenge for creating value sets using traditional elicitation techniques, such as time trade-off. A promising alternative method, called Online elicitation of Personal Utility Functions (OPUF) has recently been proposed. The aim of this study was to test the feasibility of using OPUF to create a value set for the EQ-HWB-S. Methods We adapted the OPUF tool for the EQ-HWB-S, and piloted it in convenience samples from the UK and Germany. We then conducted an explorative valuation study in both countries in March 2023. We recruited a total of 658 respondents, in four samples: UK (n = 328) and German (n = 110) general population, and German rheumatic disease (n = 110) and diabetes (n = 110) patients. Feasibility was assessed based on completion times, data quality, logical consistency, and respondents’ feedback. A demo version of the English OPUF survey is available at: https://valorem.health/eqen-demo Results Median completion times ranged from 11 to 16 minutes across samples. The OPUF approach yielded well-ordered value set coefficients in all four samples, with precision comparable to a larger EQ-VT study (n = 520). Pain, mobility, and daily activities were the three most important dimensions across all samples. The OPUF-derived UK value set differed from the EQ-VT pilot value set in relative dimension weights, intermediate level positions, and overall scaling. Conclusion The OPUF approach was feasible for creating value sets for the EQ-HWB-S in four relatively small samples, including two patient groups. While further validation is needed, OPUF may offer a viable alternative or supplement to traditional valuation techniques for eliciting health state preferences, particularly in settings with limited resources or when eliciting preferences from specific groups.

Idiopathic multicentric Castleman disease (iMCD) is a rare, chronic, debilitating lymphoproliferative disorder where the mainstay of treatment is symptom management. Our recent international patient survey showed that patients with iMCD have a high symptom burden that has a significant negative patient-reported impact on several aspects of daily life. As part of our ongoing work towards the development of an iMCD symptom burden scale, assessing the survey’s psychometric properties is a critical step in understanding its adequacy, relevance, and usefulness. As iMCD is a rare disease, there are challenges to conducting such psychometric analyses which we describe. As part of the exploratory psychometric analysis, three a priori hypothesis sets (HS) were generated by interviewing an iMCD-experienced clinician, a patient, and a caregiver to explore the iMCD patient survey’s internal construct validity, given no gold standard iMCD measure exists for external construct validation. HS-1 hypothesized that a convergent or discriminant relationship exists with the patients’ self-assessment of symptom effect on daily life between two potentially related or unrelated symptoms, respectively. HS-2 hypothesized that having a greater number of symptoms has a positive convergent relationship with the patients’ assessment of symptoms’ effect on daily life. Finally, HS-3 hypothesized that patients receiving treatment versus no treatment was associated with patients reporting less effect of symptom burden on their daily life. Spearman’s rank absolute correlation strength (ACS) was used for HS-1 and HS-2 (convergent relationship, ACS ≥ 0.3 and p value < 0.05; divergent relationship, ACS < 0.3), and Cohen’s d to quantify standardized absolute effect sizes (AES) for HS-3 (AES ≥ 0.5 and p value < 0.05). Our analyses partially supported HS-1. None of the three positive convergent relationships were supported. Of the six discriminant relationships, only dizziness with impaired cognitive function and tiredness with dizziness were supported. HS-2 analyses showed there was convergent validity between the number of symptoms and their effect on aspects of daily life. HS-3 analyses did not provide evidence to support the hypothesis. These internal psychometric construct analyses provide initial support for the bespoke iMCD patient survey and will guide additional work towards the development of the first iMCD-specific symptom burden scale.

OBJECTIVES:This study generates VILL-UI (Vision Impairment in Low Luminance - Utility Index), a preference-weighted measure (PWM) derived from the VILL-33 measure for use in patients with age-related macular degeneration (AMD) and valued to generate United Kingdom and German preference weights. METHODS:A PWM consists of a classification system to describe health and utility values for every state described by the classification. The classification was derived using existing data collected as part of the MACUSTAR study, a low-interventional study on AMD, conducted at 20 clinical sites across Europe. Items were selected using psychometric and Rasch analyses, published criteria around PWM suitability, alongside instrument developer views and concept elicitation work that informed VILL-33 development. An online discrete choice experiment (DCE) with duration of the health state was conducted with the United Kingdom and German public. Responses were modeled to generate utility values for all possible health states. RESULTS:The classification system has 5 items across the 3 domains of VILL-33: reading and accessing information, mobility and safety, and emotional well-being. The DCE samples (United Kingdom: n = 1004, Germany: n = 1008) are broadly representative and demonstrate good understanding of the tasks. The final DCE analyses produce logically consistent and significant coefficients. CONCLUSIONS:This study enables responses to VILL-33 to be directly used to inform economic evaluation in AMD. The elicitation of preferences from both United Kingdom and Germany enables greater application of VILL-UI for economic evaluation throughout Europe. VILL-UI fills a gap in AMD in which generic preference-weighted measures typically lack sensitivity.

This paper considers the development and evolution of the short-form 6 dimensions (SF-6D), a generic preference-weighted measure consisting of a health classification with accompanying value set that was developed from one of the widest used health related quality of life measures, the SF-36 health survey. This enabled health state utility values to be directly generated from SF-36 and SF-12 data for a range of purposes, including to produce quality adjusted life years for use in economic evaluation of healthcare interventions across a range of different conditions and treatments. This paper considers the rationale for the development of the measure, the development process, performance and how the SF-6D has evolved since its conception. This includes the development of an updated version, SF-6D version 2 (SF-6Dv2), which was generated to deal with some criticisms of the first version, and now includes a standalone version for inclusion in studies without relying on use of SF-36 or SF-12. Valuation methods have also evolved, from standard gamble in-person interviews to online discrete choice experiment surveys. International work related to the SF-6Dv1 and SF-6Dv2 is considered. We also consider recommendations for use, highlighting key psychometric evidence and reimbursement agency recommendations.

The SF-6D Classification System was recently updated (SF-6Dv2). We performed a valuation survey to construct a value set for the SF-6Dv2 in Japan. An online discrete choice experiment (DCE) with duration was used to estimate a value set for the SF-6Dv2 for Japan based on public preferences. The target sample number was 3800. Respondents were asked to complete 15 choice tasks. A conditional logit model that estimates interactions between time and each dimension was used to develop the value set. The collected sample included 3933 respondents for the DCE tasks. The results of all the unconstrained models showed some inconsistencies. In particular, inconsistencies in the two most severe levels of the role limitation (RL) and vitality (VT) dimensions were observed in all models. The number of inconsistencies was smallest in a core model (n = 3) and in a model for core and common health states (n = 2). The physical functioning (PF) and pain (PA) dimensions had the greatest influence on utility at the overall level across all models. RL, VT, and social functioning (SF) had smaller overall impacts on utility. The PF weights for the two most severe levels are much lower than those in the UK and Australia. The Japanese scores tended to be lower compared with the UK SF-6Dv2 scores. We obtained a value set for Japan (model 5). With the development of this value set, it is now possible to calculate quality-adjusted life years for economic evaluation in Japan when the SF-6Dv2 has been used.

A new method has recently been developed for valuing health states, called 'Online elicitation of Personal Utility Functions' (OPUF). In contrast to established methods, such as time trade-off or discrete choice experiments, OPUF does not require hundreds of respondents, but allows estimating utility functions for small groups and even at the individual level. In this study, we used OPUF to elicit EQ-5D-5L health state preferences from a (not representative) sample of the UK general population, and then compared utility functions on the societal-, group-, and individual level. A demo version of the survey is available at: https://eq5d5l.me. Data from 874 respondents were included in the analysis. For each respondent, we constructed a personal EQ-5D-5L value set. These personal value sets predicted respondents' choices in three hold-out discrete choice tasks with an accuracy of 78%. Overall, preferences varied greatly between individuals. However, PERMANOVA analysis showed that demographic characteristics explained only a small proportion of the variability between subgroups. While OPUF is still under development, it has important strengths: it can be used to construct value sets for patient reported outcome instruments such as EQ-5D-5L, while also allowing examination of underlying preferences in an unprecedented level of detail. In the future, OPUF could be used to complement existing methods, allowing valuation studies in smaller samples, and providing more detailed insights into the heterogeneity of preferences across subgroups.

Background/aims To further validate the Vision Impairment in Low Luminance (VILL) questionnaire, which captures visual functioning and vision-related quality of life (VRQoL) under low luminance, low-contrast conditions relevant to age-related macular degeneration (AMD). Methods The VILL was translated from German into English (UK), Danish, Dutch, French, Italian and Portuguese. Rasch analysis was used to assess psychometric characteristics of 716 participants (65% female, mean age 72±7 years, 82% intermediate AMD) from the baseline visit of the MACUSTAR study. In a subset of participants (n=301), test–retest reliability (intraclass correlation coefficient (ICC) and coefficient of repeatability (CoR)) and construct validity were assessed. Results Four items were removed from the VILL with 37 items due to misfit. The resulting Vision Impairment in Low Luminance with 33 items (VILL-33) has three subscales with no disordered thresholds and no misfitting items. No differential item functioning and no multidimensionality were observed. Person reliability and person separation index were 0.91 and 3.27 for the Vision Impairment in Low Luminance Reading Subscale (VILL-R), 0.87 and 2.58 for the Vision Impairment in Low Luminance Mobility Subscale (VILL-M), and 0.78 and 1.90 for the Vision Impairment in Low Luminance Emotional Subscale (VILL-E). ICC and CoR were 0.92 and 1.9 for VILL-R, 0.93 and 1.8 for VILL-M and 0.82 and 5.0 for VILL-E. Reported VRQoL decreased with advanced AMD stage (p<0.0001) and was lower in the intermediate AMD group than in the no AMD group (p≤0.0053). Conclusion The VILL is a psychometrically sound patient-reported outcome instrument, and the results further support its reliability and validity across all AMD stages. We recommend the shortened version of the questionnaire with three subscales (VILL-33) for future use. Trial registration number NCT03349801.

Objectives: The EQ Health and Wellbeing Short (EQ-HWB-S) is a new generic measure that covers health and wellbeing developed for use in economic evaluation in health and social care. The aim was to test the feasibility of using composite time trade-off (cTTO) and a discrete choice experiment (DCE) based on an international protocol to derive utilities for the EQ-HWB-S and to generate a pilot value set.Methods: A representative UK general population was recruited. Online videoconference interviews were undertaken where cTTO and DCE tasks were administered using EuroQol Portable Valuation Technology. Quality control (QC) was used to assess interviewers' performance. Data were modeled using Tobit, probit, and hybrid models. Feasibility was assessed based on the distribution of data, participants, and reports of understanding from the interviewer, QC and modeling results.Results: cTTO and DCE data were available for 520 participants. Demographic characteristics were broadly representative of the UK general population. Interviewers met QC requirements. cTTO values ranged between-1 to 1 with increasing disutility associated with more severe states. Participants understood the tasks and the EQ-HWB-S states; and the interviewers reported high levels of understanding and engagement. The hybrid Tobit heteroscedastic model was selected for the pilot value set with values ranging from-0.384 to 1. Pain, mobility, daily activities, and sad/depressed had the largest disutilities, followed by loneliness, anxiety, exhaustion, control, and cognition in the selected model.Conclusions: EQ-HWB-S can be valued using cTTO and DCE. Further methodological work is recommended to develop a valuation protocol specific to the EQ-HWB-S.

An increasing number of prospective parents are experiencing infertility along with associated negative impacts on mental health and life satisfaction that can extend across a network of individuals and family members. Assistive reproductive technologies (ART) can help prospective parents achieve their parenthood goals but, like any health technology, they must demonstrate acceptable 'value for money' to qualify for public funding. We argue that current approaches to understanding the value of ART, including quality-adjusted life-year (QALY) gains based on changes in health-related quality of life (HRQOL) and, more often, cost per live birth, are too narrow to capture the full impact of unmet parenthood goals and ART. We see a fundamental disconnect between measures of HRQOL and broader measures of wellbeing associated with met and unmet parenthood goals. We also suggest that simple concepts such as 'patient' and 'carer' are of limited applicability in the context of ART, where 'spillovers' extend across a wide network of individuals, and the person receiving treatment is often not the infertile individual. Consideration of individual and societal wellbeing beyond HRQOL is necessary to understand the full range of negative impacts associated with unmet parenthood goals and the corresponding positive impacts of successful ART. We suggest moving towards a wellbeing perspective on value to achieve a fuller understanding of value and promote cross-sector allocative efficiency.

Objectives: Traditional preference elicitation methods, such as discrete choice experiments or time trade-off, usually require large sample sizes. This can limit their applicability in patient populations, where recruiting enough participants can be The objective of this study was to test a new method, called the Online elicitation of Personal Utility Functions (OPUF) approach, to derive an EQ-5D-5L value set from a relatively small sample of patients with rheumatic diseases. Methods: OPUF is a new type of online survey that implements compositional preference elicitation techniques. Central to the method are 3 valuation steps: (1) dimension weighting, (2) level rating, and (3) anchoring. An English demo version of the OPUF survey can be accessed at https://valorem.health/eq5d5l. From the responses, a personal EQ-5D-5L utility function can be constructed for each participant, and a group-level value set can be derived by aggregating model coefficients across Results: A total of 122 patients with rheumatic disease from Germany completed the OPUF survey. The survey was generally well received; most participants completed the survey in less than 20 minutes and were able to derive a full EQ-5D-5L value set. The precision of mean coefficients was high, despite the small sample size. Conclusions: Our findings demonstrate that OPUF can be used to derive an EQ-5D-5L value set from a relatively small sample of patients. Although the method is still under development, we think that it has the potential to be a valuable preference elicitation tool and to complement traditional methods in several areas.

Objectives: Cystic fibrosis (CF) limits survival and negatively affects health-related quality of life (HRQOL). Cost-effectiveness analysis (CEA) may be used to make reimbursement decisions for new CF treatments; nevertheless, generic utility measures used in CEA, such as EQ-5D, are insensitive to meaningful changes in lung function and HRQOL in CF. Here we develop a new, CF disease-specific, preference-based utility measure based on the adolescent/adult version of the Cystic Fibrosis Questionnaire-Revised (CFQ-R), a widely used, CF-specific, patient-reported measure of HRQOL.Methods: Blinded CFQ-R data from 4 clinical trials (NCT02347657, NCT02392234, NCT01807923, and NCT01807949) were used to identify discriminating items for a classification system using psychometric (eg, factor and Rasch) analyses. Thirty-two health states were selected for a time trade-off (TTO) exercise with a representative sample of the UK general population. TTO utilities were used to estimate a preference-based scoring algorithm by regression analysis (tobit models with robust standard errors clustered on participants with censoring at 21).Results: A classification system with 8 dimensions (CFQ-R-8 dimensions; physical functioning, vitality, emotion, role func-tioning, breathing difficulty, cough, abdominal pain, and body image) was generated. TTO was completed by 400 participants (mean age, 47.3 years; 49.8% female). Among the regression models evaluated, the tobit heteroscedastic-ordered model was preferred, with a predicted utility range from 0.236 to 1, no logical inconsistencies, and a mean absolute error of 0.032.Conclusion: The CFQ-R-8 dimensions is the first disease-specific, preference-based scoring algorithm for CF, enabling estimation of disease-specific utilities for CEA based on the well-validated and widely used CFQ-R.

Topic: 36. Ethics and health economics Background: Idiopathic multicentric Castleman disease (iMCD) is a rare, life-threatening lymphoproliferative disorder characterized by systemic inflammatory symptoms, generalized lymphadenopathy, polyclonal lymphoproliferation, and multiple organ system dysfunction caused by a hyperinflammatory state. Patients experience high symptom burden and the mainstay of iMCD management is symptom control and preventing severe complications. Consequently, the quantification of symptoms and their impact on the daily lives could be a valuable clinical tool to monitor disease status, functional state, and response to treatment. Aims: Efforts to catalogue and understand how iMCD symptoms impact daily living from an international survey have been reported elsewhere. We conduct an exploratory analysis of the survey’s psychometric properties in terms of internal construct validity (i.e., assessing against factors in the same questionnaire with a similar construct) to assess its suitability for the generation of a Symptom Burden Scale. Methods: An online symptom burden survey specifically tailored to iMCD, was developed, based on literature and clinical expert advice. This survey was distributed within iMCD communities in Australia, Canada, the UK, and the US through the Castleman Disease Collaborative Network (CDCN). Ethics approval and patient consent were obtained. Following analysis of the responses relating to symptom burden, their severity (measured on a Likert scale: range 0-4), and the impact on their daily lives, exploratory analyses regarding the strength of the relationship between symptoms and their impact on daily activities were undertaken. Firstly, interviews with clinicians, patients and caregivers were conducted to understand whether response could be grouped as the same or related to one another. If items were related, the expected strength of the relationship and, for the clinical expert interviews only, the potential direction of relationship, were further explored. Secondly, hypotheses were generated a priori from these interviews and tested to establish the construct, convergent and discriminant validity of the survey. Spearman’s rank absolute correlation strength associated p-value, and Cohen’s d standardized effect size methods were utilized. Results: The survey was implemented from April–November 2020, with 51 respondents reporting confirmed iMCD diagnosis from a healthcare practitioner. Patients were predominantly female (56.9%), of mean age of 47.4 years (SD 11.9) and white (74.5%). The mean number of symptoms reported was 6.7 (SD: 5.2, Range: 0-22). Three a priori hypothesis sets were generated: 1. How specific symptoms relate to each other; 2. Number of symptoms and their relationship with aspects of daily life; and 3. Receiving treatment and the overall relationship with aspects of daily life. Although the results did support or negate all a priori hypotheses, a strong significant correlation between having a higher number of symptoms and greater adverse impact on daily life was identified. Summary/Conclusion: Despite sample size limitations for complex statistical analyses, this exploratory analysis provides confidence in the internal construct validity of the survey. It supports use of this disease burden questionnaire as a tool for the assessment of patients’ symptom state and evaluation of response in daily practice or clinical research. Keywords: Castleman’s disease, Patient

Background Idiopathic Multicentric Castleman Disease (iMCD) is a rare inflammatory lymphoproliferative disorder with heterogenous clinical presentations. The symptomatology in iMCD patients remains poorly understood. The aim of this study was to identify the type, frequency and severity of iMCD-related symptoms and the impact of these on the daily lives of iMCD patients and informal-caregivers. Methods We conducted two bespoke 45-question online surveys for iMCD patients and informal-caregivers of patients recruited from the US, UK, Australia and Canada between April 14 and November 8, 2021. Descriptive data was collected, and a Likert scale was used to quantify the impact of symptoms on various aspects of daily life. Ordinal logistic regression analysis was used to determine associations between age, gender, employment status and symptom burden with aspects of daily life. Findings Eligible respondents included 51 iMCD patients and 11 informal-caregivers. Patients reported up to 27 unique symptoms, the mean number of symptoms experienced by a patient was 6.7 (range 0-22 symptoms). Most symptoms had a moderate to severe impact on patients' daily lives, with 'pain/discomfort' , 'ability to travel' , and 'sexual functioning' being the most impacted. iMCD patient characteristics such as being 40 years or older, female, and either disabled or unemployed was significantly associated with adverse impact on several aspects of daily life. Among caregivers, the aspects of daily life that were disproportionately affected was their own social life and freedom, emotional wellbeing, travel/relocation, and work. Interpretation iMCD patients have widely varied and unappreciated symptomatology. High symptom burden adversely impacts several aspects of patient daily lives as well as their caregivers. Funding Funding was provided by EUSA Pharma.Copyright (c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

BACKGROUND:Discrete choice experiments (DCEs) are increasingly used in health state valuation studies.OBJECTIVE:This systematic review updates the progress and new findings of DCE studies in the health state valuation, covering the period since the review of June 2018 to November 2022. The review reports the methods that are currently being used in DCE studies to value health and study design characteristics, and, for the first time, reviews DCE health state valuation studies published in the Chinese language.METHODS:English language databases PubMed and Cochrane, and Chinese language databases Wanfang and CNKI were searched using the self-developed search terms. Health state valuation or methodology study papers were included if the study used DCE data to generate a value set for a preference-based measure. Key information extracted included DCE study design strategies applied, methods for anchoring the latent coefficient on to a 0-1 QALY scale and data analysis methods.RESULTS:Sixty-five studies were included; one Chinese language publication and 64 English language publications. The number of health state valuation studies using DCE has rapidly increased in recent years and these have been conducted in more countries than prior to 2018. Wide usage of DCE with duration attributes, D-efficient design and models accounting for heterogeneity has continued in recent years. Although more methodological consensus has been found than in studies conducted prior to 2018, this consensus may be driven by valuation studies for common measures with an international protocol (the 'model' valuation research). Valuing long measures with well-being attributes attracted attention and more realistic design strategies (e.g., inconstant time preference, efficient design and implausible states design) were identified. However, more qualitative and quantitative methodology study is still necessary to evaluate the effect of those new methods.CONCLUSIONS:The use of DCEs in health state valuation continues to grow dramatically and the methodology progress makes the method more reliable and pragmatic. However, study design is driven by international protocols and method selection is not always justified. There is no gold standard for DCE design, presentation format or anchoring method. More qualitative and quantitative methodology study is recommended to evaluate the effect of new methods before researchers make methodology decisions.

The recent article by Crossnohere et al. assessed the ‘‘appropriateness’’ of the EQ-5D for use as a measure of health status in Duchenne muscular dystrophy (DMD). This was investigated in terms of the instrument’s responsiveness (to differences in health status), convergent validity (correlation with disease-specific measures), feasibility and burden (how easy was the EQ-5D to understand and answer), and some minimal tests of content validity (did the participants think that the EQ-5D was consistent with ‘‘health status’’). In their abstract, the researchers conclude that they ‘‘found support for the appropriateness of EQ-5D to assess health status in Duchenne.’’ We welcome the research by Crossnohere et al., but we would like to make explicit the caveat to their conclusion that the researchers conducted a very limited assessment of the content validity of the EQ-5D for use in measuring health status (or health-related quality of life, as used elsewhere in the article) in DMD. While this is acknowledged in the Discussion section of the article, it is not clear in the Methods section or in the abstract, and there is the concern that this caveat may therefore be lost on a more casual reader. Content validity is regarded as the most important psychometric property of any patient-reported outcome measure (PROM) according to the widely respected COSMIN guidelines, which should necessarily extend to preference-based measures used to generate utilities (as a special category of PROMs). Put simply, before a measure is used to inform quality-adjusted life-years in costutility analysis, you would want to make sure you are measuring the right thing(s) (and in this context, when considering health-related quality of life, we argue that should be the domains that matter most to patients). A fuller assessment of content validity would involve asking participants, usually in a more in-depth interview setting, whether the instrument is comprehensive (i.e., nothing important is missing), each item is relevant (i.e., applicable to the target population and context of use), and each item is comprehensible (i.e., understood as the developers or researchers intended). Crossnohere et al.

Objectives: Existing measures for estimating quality-adjusted life-years are mostly limited to health-related quality of life. This article presents an overview of the development the EQ-HWB (EQ Health and Wellbeing), which is a measure that encompasses health and wellbeing. Methods: Stages: (1) Establishing domains through reviews of the qualitative literature informed by a conceptual framework. (2) Generation and selection of items to cover the domains. (3) Face validation of these items through qualitative interviews with 168 patients, social care users, general population, and carers across 6 countries (Argentina, Australia, China, Germany, United Kingdom, United States). (4) Extensive psychometric testing of candidate items (using classical, factor analysis, and item response theory methods) on. 4000 respondents in the 6 countries. Stakeholders were consulted throughout. Results: A total of 32 subdomains grouped into 7 high-level domains were identified from the qualitative literature and 97 items generated to cover them. Face validation eliminated 36 items, modified 14, and added 3. Psychometric testing of 64 items found little difference in missing data or problems with response distribution, the conceptual model was confirmed except in China, and most items performed well in the item response theory in all countries. Evidence was presented to stakeholders in 2 rounds of consultation to inform the final selection of items for the EQ-HWB (25-item) and the short version of EQ-HWB (9-items). Conclusions: EQ-HWB measures have been developed internationally for evaluating interventions in health, public health, and social care including the impact on patients, social care users, and carers.

Objective Idiopathic multicentric Castleman's disease (iMCD) is a rare lymphoproliferative disorder driven by proinflammatory hypercytokinemia. Patient perspective of the burden and associated symptoms of iMCD on their daily life have not been previously studied. We developed a bespoke international online survey to investigate, characterize, and map the symptoms and associated burden on daily life experienced by patients with various subtypes of iMCD. Statistical analysis was conducted to explore the psychometric properties of the survey. Methods A survey to elicit the burden of disease-related symptoms and their effects on daily life from a patient perspective was developed using information from clinical practice and published literature. Eligible patients were >18 years old having physician-confirmed diagnosis of iMCD. The survey was distributed within iMCD communities in Australia, Canada, the UK, and the US through the Castleman Disease Collaborative Network (CDCN). Hypotheses were generated based on expert opinion (one clinician, one patient, and one caregiver) in one-to-one interviews to understand whether specific questions and response options within the patient questionnaire could be: 1. grouped together as the same; 2. related to one another; or 3. if items were related, the expected strength of the relationship and the potential direction of relationship. Spearman's rank absolute correlation strength and Cohen's-d standardized effect size methods, alongside estimating relevant p-values, were used to explore these relationships. The overall study programme is depicted in Figure 1, with details of the study design captured in Figure 2. Results Overall, 57 patients with iMCD completed the survey between April-November 2021. Patients experienced a mean number of 7 symptoms a week (range: 0 to 22 symptoms), highlighting the burden iMCD on patient. To explore the robustness of these results, three a priori hypothesis sets were generated as a result of the expert interviews: 1. how specific symptoms relate to each other; 2. number of symptoms and their relationship with aspects of daily life; and 3. receiving treatment or not, and the overall relationship with aspects of daily life. 9 symptom pairs were identified for exploration, however as the number of symptoms experienced by patients with iMCD was so high and heterogeneous, in reality only 2 of the pairs were identified to be statistically significant due to small response numbers for other pairings. There was a moderate positive relationship between tiredness and physical weakness, and a weak positive relationship between tiredness and dizziness. There was a strong correlation between having a higher number of symptoms and greater adverse association with daily life, as depicted in Table 1. On reflection, it was realised that cross-sectional data as is the case in this survey was not appropriate for exploring links between treatment or not, and associated aspects of daily life as we have no indication of the baseline for the patients. The collecting of longitudinal data in such future research would support such analysis and increase the likelihood of making meaningful observations. A longitudinal approach would further add value to these results be gathering information on how iMCD progresses from a patient perspective. Conclusion To our knowledge this is the first study to characterise symptom burden of iMCD and its impact on daily living. The exploratory psychometric testing provides a level of confidence in the construct validity of the survey such that the results can hopefully be used to ultimately develop symptom burden score that can help assessment of disease severity, treatment decisions and evaluating responses in daily practice and clinical research. The exploratory testing also highlighted the challenges of working with naturally small samples sizes and the importance of recognising the limitations of what can be done with a data set given the data collection design. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Introduction Standard valuation methods, such as TTO and DCE are inefficient. They require data from hundreds if not thousands of participants to generate value sets. Here, we present the Online elicitation of Personal Utility Functions (OPUF) tool; a new type of online survey for valuing EQ-5D-5L health states using more efficient, compositional elicitation methods, which even allow estimating value sets on the individual level. The aims of this study are to report on the development of the tool, and to test the feasibility of using it to obtain individual-level value sets for the EQ-5D-5L. Methods We applied an iterative design approach to adapt the PUF method, previously developed by Devlin et al., for use as a standalone online tool. Five rounds of qualitative interviews, and one quantitative pre-pilot were conducted to get feedback on the different tasks. After each round, the tool was refined and re-evaluated. The final version was piloted in a sample of 50 participants from the UK. A demo of the EQ-5D-5L OPUF survey is available at: https://eq5d5l.me Results On average, it took participants about seven minutes to complete the OPUF Tool. Based on the responses, we were able to construct a personal EQ-5D-5L value set for each of the 50 participants. These value sets predicted a participants' choices in a discrete choice experiment with an accuracy of 80%. Overall, the results revealed that health state preferences vary considerably on the individual-level. Nevertheless, we were able to estimate a group-level value set for all 50 participants with reasonable precision. Discussion We successfully piloted the OPUF Tool and showed that it can be used to derive a group-level as well as personal value sets for the EQ-5D-5L. Although the development of the online tool is still in an early stage, there are multiple potential avenues for further research.