title: Learning and satisficing: an analysis of sequence effects in health valuation.
abstract: OBJECTIVE
  To estimate the effect of sequence on response precision and response behavior in health valuation studies.
  
  
  METHODS
  Time trade-off (TTO) and paired comparison responses from six health valuation studies-four US, one Spanish, and one Dutch-were examined (22,225 respondents) to test whether task sequence influences response precision (e.g., rounding), response changes, and median response times. Each study used a computer-based instrument that randomized task sequence among a national sample of adults, age 18 years or older, from the general population.
  
  
  RESULTS
  For both TTO and paired comparisons, median response times decreased with sequence (i.e., learning), but tended to flatten after the first three tasks. Although the paired comparison evidence demonstrated that sequence had no effect on response precision, the frequency of rounded TTO responses (to either 1-year or 5-year units) increased with sequence.
  
  
  CONCLUSIONS
  Based on these results, randomizing or reducing the number of paired comparison tasks does not appear to influence response precision; however, generalizability, practicality, and precautionary considerations remain. Overall, participants learned to respond efficiently within the first three tasks and did not resort to satisficing, but may have rounded their TTO responses.
authors.affiliation: Health Outcomes and Behavior, Moffitt Cancer Center and University of South Florida, Tampa, FL, USA. Electronic address: benjamin.craig@moffitt.org.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Craig
authors.affiliation: Health Outcomes and Behavior, Moffitt Cancer Center and University of South Florida, Tampa, FL, USA.
authors.forename: Shannon K
authors.initials: SK
authors.lastname: Runge
authors.affiliation: Department of Health Management and Health Economics, University of Oslo, Oslo, Norway.
authors.forename: Kim
authors.initials: K
authors.lastname: Rand-Hendriksen
authors.affiliation: Canary Islands Health Service (SESCS), Santa Cruz de Tenerife, Spain.
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: Ramos-Goñi
authors.affiliation: Institute for Medical Technology Assessment, Erasmus University Rotterdam, Rotterdam, The Netherlands.
authors.forename: Mark
authors.initials: M
authors.lastname: Oppe
mesh_terms: D000328:Adult; D002755:Choice Behavior; D006304:Health Status; D006801:Humans; D007858:Learning; D009426:Netherlands / Q000453:epidemiology; D011597:Psychomotor Performance; D011930:Reaction Time; D013030:Spain / Q000453:epidemiology; D013997:Time Factors; D014481:United States / Q000453:epidemiology
keywords: QALY; health valuation; paradata; preferences; response precision; sequence effects; time trade-off