title: Lead time TTO: leading to better health state valuations?
abstract: Preference elicitation tasks for better than dead (BTD) and worse than dead (WTD) health states vary in the conventional time trade-off (TTO) procedure, casting doubt on uniformity of scale. 'Lead time TTO' (LT-TTO) was recently introduced to overcome the problem. We tested different specifications of LT-TTO in comparison with TTO in a within-subject design. We elicited preferences for six health states and employed an intertemporal ranking task as a benchmark to test the validity of the two methods. We also tested constant proportional trade-offs (CPTO), while correcting for discounting, and the effect of extending the lead time if a health state is considered substantially WTD. LT-TTO produced lower values for BTD states and higher values for WTD states. The validity of CPTO varied across tasks, but it was higher for LT-TTO than for TTO. Results indicate that the ratio of lead time to disease time has a greater impact on results than the total duration of the time frame. The intertemporal ranking task could not discriminate between TTO and LT-TTO.
authors.affiliation: iBMG/iMTA, Erasmus University Rotterdam, Rotterdam, The Netherlands. attema@bmg.eur.nl
authors.forename: Arthur E
authors.initials: AE
authors.lastname: Attema
authors.forename: Matthijs M
authors.initials: MM
authors.lastname: Versteegh
authors.forename: Mark
authors.initials: M
authors.lastname: Oppe
authors.forename: Werner B F
authors.initials: WB
authors.lastname: Brouwer
authors.forename: Elly A
authors.initials: EA
authors.lastname: Stolk
mesh_terms: D000328:Adult; D001294:Attitude to Health; D004470:Economics, Medical; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D057240:Patient Preference / Q000523:psychology*; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D013997:Time Factors