Marieke Geertruida Maria Weernink

Valuing Treatments for Parkinson Disease Incorporating Process Utility: Performance of Best-Worst Scaling, Time Trade-Off, and Visual Analogue Scales

OBJECTIVE The objective of this study was to compare treatment profiles including both health outcomes and process characteristics in Parkinson disease using best-worst scaling (BWS), time trade-off (TTO), and visual analogue scales (VAS). METHODS From the model comprising of seven attributes with three levels, six unique profiles were selected representing process-related factors and health outcomes in Parkinson disease. A Web-based survey (N = 613) was conducted in a general population to estimate process-related utilities using profile-based BWS (case 2), multiprofile-based BWS (case 3), TTO, and VAS. The rank order of the six profiles was compared, convergent validity among methods was assessed, and individual analysis focused on the differentiation between pairs of profiles with methods used. RESULTS The aggregated health-state utilities for the six treatment profiles were highly comparable for all methods and no rank reversals were identified. On the individual level, the convergent validity between all methods was strong; however, respondents differentiated less in the utility of closely related treatment profiles with a VAS or TTO than with BWS. For TTO and VAS, this resulted in nonsignificant differences in mean utilities for closely related treatment profiles. CONCLUSIONS This study suggests that all methods are equally able to measure process-related utility when the aim is to estimate the overall value of treatments. On an individual level, such as in shared decision making, BWS allows for better prioritization of treatment alternatives, especially if they are closely related. The decision-making problem and the need for explicit trade-off between attributes should determine the choice for a method.

Patient preference for radial versus femoral vascular access for elective coronary procedures: The PREVAS study

To explore patient preference for vascular access site in percutaneous coronary procedures, the perceived importance of benefits and risks of transradial access (TRA) and transfemoral access (TFA) were assessed. In addition, direct preference for vascular access and preference for shared decision making (SDM) were evaluated.

Involving Patients in Weighting Benefits and Harms of Treatment in Parkinson's Disease

Introduction Little is known about how patients weigh benefits and harms of available treatments for Parkinson’s Disease (oral medication, deep brain stimulation, infusion therapy). In this study we have (1) elicited patient preferences for benefits, side effects and process characteristics of treatments and (2) measured patients’ preferred and perceived involvement in decision-making about treatment. Methods Preferences were elicited using a best-worst scaling case 2 experiment. Attributes were selected based on 18 patient-interviews: treatment modality, tremor, slowness of movement, posture and balance problems, drowsiness, dizziness, and dyskinesia. Subsequently, a questionnaire was distributed in which patients were asked to indicate the most and least desirable attribute in nine possible treatment scenarios. Conditional logistic analysis and latent class analysis were used to estimate preference weights and identify subgroups. Patients also indicated their preferred and perceived degree of involvement in treatment decision-making (ranging from active to collaborative to passive). Results Two preference patterns were found in the patient sample (N = 192). One class of patients focused largely on optimising the process of care, while the other class focused more on controlling motor-symptoms. Patients who had experienced advanced treatments, had a shorter disease duration, or were still employed were more likely to belong to the latter class. For both classes, the benefits of treatment were more influential than the described side effects. Furthermore, many patients (45%) preferred to take the lead in treatment decisions, however 10.8% perceived a more passive or collaborative role instead. Discussion Patients weighted the benefits and side effects of treatment differently, indicating there is no “one-size-fits-all” approach to choosing treatments. Moreover, many patients preferred an active role in decision-making about treatment. Both results stress the need for physicians to know what is important to patients and to share treatment decisions to ensure that patients receive the treatment that aligns with their preferences.

Insufficient vitamin D supplement use during pregnancy and early childhood: a risk factor for positional skull deformation

Vitamin D insufficiency during pregnancy is associated with disturbed skeletal homeostasis during infancy. Our aim was to investigate the influence of adherence to recommendations for vitamin D supplement intake of 10 μg per day (400 IU) during pregnancy (mother) and in the first months of life (child) on the occurrence of positional skull deformation of the child at the age of 2 to 4 months. In an observational case-control study, two hundred seventy-five 2- to 4-month-old cases with positional skull deformation were compared with 548 matched controls. A questionnaire was used to gather information on background characteristics and vitamin D intake (food, time spent outdoors and supplements). In a multiple variable logistic regression analysis, insufficient vitamin D supplement intake of women during the last trimester of pregnancy [adjusted odds ratio (aOR) 1.86, 95% (CI) 1.27-2.70] and of children during early infancy (aOR 7.15, 95% CI 3.77-13.54) were independently associated with an increased risk of skull deformation during infancy. These associations were evident after adjustment for the associations with skull deformation that were present with younger maternal age and lower maternal education, shorter pregnancy duration, assisted vaginal delivery, male gender and milk formula consumption after birth. Our findings suggest that non-adherence to recommendations for vitamin D supplement use by pregnant women and infants are associated with a higher risk of positional skull deformation in infants at 2 to 4 months of age. Our study provides an early infant life example of the importance of adequate vitamin D intake during pregnancy and infancy.

PIH66 – A Systematic Review To Identify the Use of Preference Elicitation Methods in Health Care Decision Making

Objectives: Preference elicitation methods (PEMs) offer the potential to increase patient-centered medical decision-making (MDM), by offering a measure of benefit along with a measure of value. Preferences can be applied in decisions on: reimbursement, including health technology assessment (HTA); market access, including benefit-risk assessment (BRA), and clinical care. The three decision contexts have different requirements for use and elicitation of preferences. The aim of this systematic review was to identify studies that used PEMs to represent the patient view and identify the types of health care decisions addressed by PEMs. Additionally, PEMs were described by methodological and practical characteristics within the three contexts’ requirements. Methods: Search terms included those related to MDM and patient preferences. Only articles with original data from quantitative PEMs were included. Results: Articles (n=322) selected included 379 PEMs, comprising matching methods (MM) (n=71,18.7%), discrete choice experiments (DCE) (n=96,25.3%), multi-criteria decision analysis (n=12,3. 2%), and other methods (i. e. rating scales), which provide estimates inconsistent with utility theory (n=200,52.8%). Most publications of PEMs had an intended use for clinical decisions (n=134,40%), HTA (n=68,20%), or BRA (n=12,4%). However, many did not specify an intended use (n=156,41.1%). In clinical decisions, rating, ranking, visual analogue scales and direct choice are used most often. In HTA, DCEs and MM are both used frequently, and the elicitation of preferences in BRA was limited to DCEs. Conclusions: Relatively simple preference methods are often adequate in clinical decisions, because they are easy to administer, give fast results, place low cognitive burden on the patient, and low analytical burden on the provider. MM and DCE fulfill the requirements of HTA and BRA but are more complex for the respondents. There were no PEMs that had low cognitive burden, and strong methodological underpinnings which could deliver adequate information to inform HTA and BRA decisions.

Individual Value Clarification Methods Based on Conjoint Analysis: A Systematic Review of Common Practice in Task Design, Statistical Analysis, and Presentation of Results:

Background. There is an increased practice of using value clarification exercises in decision aids that aim to improve shared decision making. Our objective was to systematically review to which extent conjoint analysis (CA) is used to elicit individual preferences for clinical decision support. We aimed to identify the common practices in the selection of attributes and levels, the design of choice tasks, and the instrument used to clarify values. Methods. We searched Scopus, PubMed, PsycINFO, and Web of Science to identify studies that developed a CA exercise to elicit individual patients’ preferences related to medical decisions. We extracted data on the above-mentioned items. Results. Eight studies were identified. Studies included a fixed set of 4–8 attributes, which were predetermined by interviews, focus groups, or literature review. All studies used adaptive conjoint analysis (ACA) for their choice task design. Furthermore, all studies provided patients with their preference results in real time, although the type of outcome that was presented to patients differed (attribute importance or treatment scores). Among studies, patients were positive about the ACA exercise, whereas time and effort needed from clinicians to facilitate the ACA exercise were identified as the main barriers to implementation. Discussion. There is only limited published use of CA exercises in shared decision making. Most studies resembled each other in design choices made, but patients received different feedback among studies. Further research should focus on the feedback patients want to receive and how the CA results fit within the patient–physician dialogue.

Are component endpoints equal? A preference study into the practice of composite endpoints in clinical trials

To examine patients’ perspectives regarding composite endpoints and the utility patients put on possible adverse outcomes of revascularization procedures.

Treatment preferences in Parkinson's disease

The objective of this dissertation was to investigate the influence of process-utility (which is the value attached to the process and convenience of care without reference to the outcome) on the relative value of treatments in Parkinson’s Disease (PD). The main treatment modalities (processes) in PD are oral intake of medication, continuous pump infusion of medication or brain surgery. This thesis clearly shows that the process of care is an important driver of preferences, in both patients with PD and in the general public. Where oral intake medication has a positive effect on the value of treatment, pump infusion and brain surgery have a detrimental effect. Furthermore, the occurrence of side effects (dizziness, drowsiness, and dyskinesia) had less impact on the perceived desirability of treatment than the treatment’s effect on motor symptoms (slow movement, posture and balance problems and tremor). In this thesis, process-utility was estimated using different techniques such as best-worst scaling, time trade-off and visual analogue scales. Results have shown all methods perform equally well with regard to distinguishing treatment alternatives on the basis of aggregated process-utility scores. However, on an individual patient-level, such as in shared decision making, the composed nature of Best-Worst Scaling allows for better prioritization of treatment alternatives. In contrast to its use in societal decision making, shared decision making requires that process characteristics are explicitly discussed with patients. What, however, is at issue here is how preferences (process-utility) should be measured. The use of stated preference methods with a strong theoretical foundation is not common in clinical decision making. Therefore the second part of this thesis focused on the use of best-worst scaling case 2 as a value clarification method to help individual patients clarify their values in treatment decisions. This thesis has found that although best-worst scaling has potential in shared decision making, methodological issues (e.g. reliability of individual preference estimations) should first be investigated before widespread implementation can take place.

PND60 - Comparison of the valuation of treatment alternatives in Parkinson's disease with best-wordt scaling, time trade-off and visual analogue scales

Objectives: Traditional valuation methods are insensitive to small improvements in process and outcome of care. Best-Worst scaling (BWS) was proposed as a sensitive and efficient method to determine the relative value of different treatments for the same disease, which would be desirable to estimate cost-effectiveness. The study objective was to compare the ability of BWS to differentiate between different treatment alternatives to that of Time Trade Off (TTO) and Visual Analogue Scales (VAS). Methods: An online survey was conducted to estimate individual values for six different treatments reflecting the real-life options in the treatment of Parkinson’s Disease with BWS2, BWS3, TTO and VAS (n=592). Pearson correlation coefficient was used to examine the strength of linear dependence between estimated utility scores. Results: Twenty-seven percent of respondents was not willing to trade life years in TTO. Only two percent of the respondent does not differentiate between the value of health states with VAS. When non-traders were excluded from the analysis, the best case scenario was valued significantly higher than the worst case scenario with all methods. Rank reversals among intermediate alternatives were common. The correlation between utility scores was very strong (VAS-BWS2 1,0; VAS-BWS3 0.98; TTO-BWS2 0.99; TTO-BWS3 0.98, BWS2-BWS3 0.96; P<0.000, n=434). Conclusions: The results demonstrate that BWS, TTO and VAS can be used to elicit incremental utility gain of small improvements in care. However, all methods have limitations. VAS does not result in utilities and some respondents do not trade with TTO. While the use of BWS is attractive because of its ability to estimate utilities for many different treatment alternatives, its applicability in CEA is limited because BWS utilities are not anchored on a 0-1 utility scale. We propose to use TTO to estimate utility for extreme health states, and to use BWS to value intermediate health states which differ on process characteristics.