title: Temporal stability of a cigarette purchase task.
abstract: BACKGROUND
  Cigarette purchase tasks (CPTs) are relatively new behavioral economic assessments that efficiently quantify motivation for tobacco by assessing how much an individual values cigarettes. This is achieved by assessing estimated cigarette consumption at escalating levels of price per cigarette and generating several measures of motivation from the resulting demand curve. The temporal stability of the indices generated from a CPT has not been examined to date and was the focus of the current study.
  
  
  METHODS
  Participants were 11 moderately heavy smokers from the community who completed CPTs and other measures on 2 occasions 1 week apart. The CPT indices of the relative value of cigarettes were (a) intensity (i.e., consumption under minimal cost), (b) O(max) (i.e., maximum expenditure for cigarettes), (c) breakpoint (i.e., first price suppressing consumption to 0), and (d) elasticity (i.e., proportionate price sensitivity).
  
  
  RESULTS
  Demand for cigarettes was initially insensitive to price changes (inelastic) but became increasingly sensitive (elastic) as prices increased. Correlations between the demand indices at both administrations were very high magnitude and statistically significant (rs = .76-.99, ps < .001), and no significant within-subjects differences were present.
  
  
  CONCLUSIONS
  These findings provide initial support for the temporal stability of motivation for tobacco as measured by a CPT. Future studies with larger samples and timeframes will be important to verify these findings.
authors.affiliation: Department of Psychology, University of Georgia, Athens, GA 30602, USA.  jmackill@uga.edu.
authors.forename: Lauren R
authors.initials: LR
authors.lastname: Few
authors.forename: John
authors.initials: J
authors.lastname: Acker
authors.forename: Cara
authors.initials: C
authors.lastname: Murphy
authors.forename: James
authors.initials: J
authors.lastname: MacKillop
mesh_terms: D000328:Adult; D005260:Female; D015438:Health Behavior; D006801:Humans; D007182:Income; D008297:Male; D008875:Middle Aged; D018803:Models, Economic; D009042:Motivation; D012907:Smoking / Q000191:economics* / Q000523:psychology; D011795:Surveys and Questionnaires; D014029:Tobacco Use Disorder / Q000191:economics* / Q000523:psychology; D044465:White People / Q000523:psychology