title: Process utility in breast biopsy.
abstract: OBJECTIVE
  To determine whether the waiting trade-off (WTO) is feasible for differentiating short-term biopsy preferences in an acute situation where anxiety is the symptomatic disease state.
  
  
  METHODS
  75 women with past experience of either breast core-needle biopsy (CNB), more invasive excisional surgical biopsy (EXB), or both, had telephone WTO assessments. Patients' baseline and test-related anxiety were valued by time trade-off (TTO) used to scale the WTO. Rating scales (RS) were obtained for convergent validity assessment with WTO and TTO.
  
  
  RESULTS
  Data were obtained in 38 women who had both CNB and EXB ("paired") and 20 who had CNB only and 16 who had EXB only ("unpaired"). Patients rated only the procedure(s) they experienced. Median paired and mean unpaired WTO scores indicated patients were willing to wait significantly longer to avoid EXB (P = 0.0003, P = 0.0002, respectively). The waiting time difference between EXB and CNB was 2.1 weeks greater in unpaired data than paired data. RS scores comparing the procedures were significantly different only for paired data (P < 0.05). Median TTO preferences for baseline (1.00) and test anxiety (0.93) obtained in 74 patients were significantly different (P < 0.0001) and consistent with RS. Correlation was noted between WTO and RS (-0.307 to -0.453, P = 0.0205 to 0.0001). The median EXB quality-adjusted life years toll (1.5 quality-adjusted life days) calculated from pooled WTO data (paired and unpaired) from 54 patients is near a threshold in a published model.
  
  
  CONCLUSIONS
  The WTO is feasible for discriminating preferences for short-term health states in an acute medical scenario where it might have been expected to be impracticable.
authors.affiliation: Indiana University, Department of Radiology Education and Research Institute, Indianapolis, USA. shannon@mgh-ita.org
authors.forename: J Shannon
authors.initials: JS
authors.lastname: Swan
authors.forename: William F
authors.initials: WF
authors.lastname: Lawrence
authors.forename: Jessica
authors.initials: J
authors.lastname: Roy
mesh_terms: D000328:Adult; D000368:Aged; D001007:Anxiety / Q000209:etiology; D001706:Biopsy / Q000523:psychology*; D001707:Biopsy, Needle / Q000523:psychology; D001940:Breast / Q000473:pathology*; D001943:Breast Neoplasms / Q000175:diagnosis / Q000523:psychology* / Q000601:surgery; D003657:Decision Making; D005260:Female; D006801:Humans; D008875:Middle Aged; D017060:Patient Satisfaction; D019057:Quality-Adjusted Life Years; D014850:Waiting Lists