title: Estimating the Danish populations' preferences for pharmacogenetic testing using a discrete choice experiment. The case of treating depression.
abstract: OBJECTIVE
  The objective is to estimate willingness-to-pay (WTP) for pharmacogenetic testing in the treatment of depression.
  
  
  METHODS
  In a web-based discrete choice questionnaire, four attributes were included: 1) number of changes in antidepressants before symptom relief; 2) time with dosage adjustments due to adverse side effects and/or lack of effects; 3) cost of pharmacogenetic testing; 4) probability of benefits from pharmacogenetic testing. Respondents were asked to choose between two scenarios; 1) pharmacogenetic testing; and 2) an opt-out option reflecting a scenario without pharmacogenetic testing. The indirect utility model was assumed to be multiplicative in probability of benefits and reduced time with dosage adjustments as well as reduced number of antidepressant changes.
  
  
  RESULTS
  Most coefficients had the expected signs and were statistically significant. WTP for avoidance of one change in antidepressant medication is 1571 Danish Krone (DKK), whereas WTP for reducing the period with dosage-adjustments by 1 month is DKK604. Both were statistically significantly different from zero.
  
  
  CONCLUSIONS
  If diagnosed with depression, peoples' WTP for pharmacogenetic testing appears to exceed its price as long as there is a reasonable probability for improvements in treatment (in the present case 10%). Utility is associated with outcomes only. Hence, other modes of provision of similar improvements in treatment may be valued equally highly. WTP estimates and the associated policy implications appear to be robust because they were unaffected by estimation model.
authors.affiliation: Danish Institute of Health Services Research, Copenhagen, Denmark. loh@dsi.dk
authors.forename: Louise
authors.initials: L
authors.lastname: Herbild
authors.forename: Mickael
authors.initials: M
authors.lastname: Bech
authors.forename: Dorte
authors.initials: D
authors.lastname: Gyrd-Hansen
mesh_terms: D000928:Antidepressive Agents / Q000191:economics / Q000627:therapeutic use*; D002755:Choice Behavior; D003657:Decision Making; D003718:Denmark; D003863:Depression / Q000188:drug therapy* / Q000191:economics / Q000235:genetics; D005820:Genetic Testing / Q000191:economics*; D006801:Humans; D018803:Models, Economic; D057240:Patient Preference / Q000191:economics*; D010597:Pharmacogenetics / Q000191:economics*; D013223:Statistics as Topic; D011795:Surveys and Questionnaires
chemical_list: D000928:Antidepressive Agents