title: Pretreatment attrition in a comparative treatment outcome study on panic disorder.
abstract: OBJECTIVE
  Whereas the fact of attrition during the course of treatment is well documented, little is known about the factors that affect sample selection before the beginning of a study ("pretreatment attrition"). The present study reports on the degree and sources of pretreatment attrition at two sites of a multicenter study on panic disorder that compared treatment outcomes for imipramine and cognitive behavior therapy.
  
  
  METHODS
  Data were collected at two clinical research sites, one with a pharmacological treatment orientation (N = 420) and one with a psychosocial treatment orientation (N = 208).
  
  
  RESULTS
  The main source of pretreatment attrition was participant refusal. At both research sites, eligible patients most often refused participation because they were either unwilling to start treatment with imipramine (30.6% and 47.4%, respectively) or discontinue their current medication (22.6% and 35.1%, respectively).
  
  
  CONCLUSIONS
  Results from comparative treatment outcome studies are limited not only to people who meet the study criteria but also to those who are willing to begin a medication treatment and discontinue their current medication.
authors.affiliation: Phobia Clinic, Hillside Hospital, Long Island Jewish Medical Center, Glen Oaks, N.Y., USA.
authors.forename: S G
authors.initials: SG
authors.lastname: Hofmann
authors.forename: D H
authors.initials: DH
authors.lastname: Barlow
authors.forename: L A
authors.initials: LA
authors.lastname: Papp
authors.forename: M F
authors.initials: MF
authors.lastname: Detweiler
authors.forename: S E
authors.initials: SE
authors.lastname: Ray
authors.forename: M K
authors.initials: MK
authors.lastname: Shear
authors.forename: S W
authors.initials: SW
authors.lastname: Woods
authors.forename: J M
authors.initials: JM
authors.lastname: Gorman
mesh_terms: D000293:Adolescent; D000328:Adult; D002985:Clinical Protocols; D015928:Cognitive Behavioral Therapy; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007099:Imipramine / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D016584:Panic Disorder / Q000188:drug therapy / Q000628:therapy*; D010349:Patient Compliance; D010352:Patient Dropouts; D018579:Patient Selection; D016896:Treatment Outcome; D016312:Treatment Refusal
chemical_list: D007099:Imipramine