title: Order of Presentation of Dimensions Does Not Systematically Bias Utility Weights from a Discrete Choice Experiment.
abstract: BACKGROUND
  Discrete choice experiments (DCEs) are increasingly used to value aspects of health. An issue with their adoption is that results may be sensitive to the order in which dimensions of health are presented in the valuation task. Findings in the literature regarding order effects are discordant at present.
  
  
  OBJECTIVE
  To quantify the magnitude of order effect of quality-of-life (QOL) dimensions within the context of a DCE designed to produce country-specific value sets for the EORTC Quality of Life Utility Measure-Core 10 dimensions (QLU-C10D), a new utility instrument derived from the widely used cancer-specific QOL questionnaire, the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30.
  
  
  METHODS
  The DCE comprised 960 choice sets, divided into 60 versions of 16 choice sets, with each respondent assigned to a version. Within each version, the order of QLU-C10D QOL dimensions was randomized, followed by life duration in the last position. The DCE was completed online by 2053 individuals in France and Germany. We analyzed the data with a series of conditional logit models, adjusted for repeated choices within respondent. We used F tests to assess order effects, correcting for multiple hypothesis testing.
  
  
  RESULTS
  Each F test failed to reject the null hypothesis of no position effect: 1) all QOL order positions considered jointly; 2) last QOL position only; 3) first QOL position only. Furthermore, the order coefficients were small relative to those of the QLU-C10D QOL dimension levels.
  
  
  CONCLUSIONS
  The order of presentation of QOL dimensions within a DCE designed to provide utility weights for the QLU-C10D had little effect on level coefficients of those QOL dimensions.
authors.affiliation: School of Public Health, Curtin University, Bentley, Western Australia, Australia. Electronic address: Richard.norman@curtin.edu.au.
authors.forename: Richard
authors.initials: R
authors.lastname: Norman
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: Georg
authors.initials: G
authors.lastname: Kemmler
authors.affiliation: Centre for Health Economics Research and Evaluation, University of Technology, Sydney, New South Wales, Australia.
authors.forename: Rosalie
authors.initials: R
authors.lastname: Viney
authors.affiliation: Department of Pharmacy Systems, Outcomes and Policy, University of Illinois at Chicago, Chicago, IL, USA.
authors.forename: A Simon
authors.initials: AS
authors.lastname: Pickard
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: Eva
authors.initials: E
authors.lastname: Gamper
authors.affiliation: Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Innsbruck, Austria.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Holzner
authors.affiliation: INSERM, Unit 1098, University of Franche-Comté, Besançon, France; Department of Pharmacy, University Hospital of Besançon, Besançon, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Nerich
authors.affiliation: Psycho-Oncology Cooperative Research Group (PoCoG), School of Psychology, University of Sydney, Sydney, New South Wales, Australia; Central Clinical School, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Madeleine
authors.initials: M
authors.lastname: King
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002755:Choice Behavior; D003661:Decision Support Techniques; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D012107:Research Design; D012959:Socioeconomic Factors; D055815:Young Adult
keywords: dimension order effects; discrete choice experiment, QLU-C10D, utility