title: Sham surgery controls in Parkinson's disease clinical trials: views of participants.
abstract: BACKGROUND
  Sham surgery controls are increasingly used in neurosurgical clinical trials in Parkinson's disease (PD) but remain controversial. We interviewed participants of such trials, specifically examining their understanding and attitudes regarding sham surgery.
  
  
  METHODS
  We conducted semistructured qualitative interviews with participants of 3 sham surgery-controlled trials for PD, focusing on their understanding of sham design, their reactions to it, its impact on decision making, and their understanding of posttrial availability of the experimental intervention and its impact on decisions to participate.
  
  
  RESULTS
  All subjects (n = 90) understood the 2-arm design; most (86%) described the procedural differences between the arms accurately. Ninety-two percent referred to scientific or regulatory reasons as rationales for the sham control, with 62% specifically referring to the placebo effect. Ninety-one percent said posttrial availability of the experimental intervention had a strong (48%) or some (43%) influence on their decision to participate, but only 68% understood the conditions for posttrial availability.
  
  
  CONCLUSIONS
  Most subjects in sham surgery-controlled PD trials comprehend the sham surgery design and its rationale. Although there is room for improvement, most subjects of sham surgery trials appear to be adequately informed.
authors.affiliation: Department of Psychiatry, University of Michigan, Ann Arbor, Michigan, USA. scottkim@med.umich.edu
authors.forename: Scott Y H
authors.initials: SY
authors.lastname: Kim
authors.forename: Raymond
authors.initials: R
authors.lastname: De Vries
authors.forename: Robert G
authors.initials: RG
authors.lastname: Holloway
authors.forename: Renee
authors.initials: R
authors.lastname: Wilson
authors.forename: Sonali
authors.initials: S
authors.lastname: Parnami
authors.forename: H Myra
authors.initials: HM
authors.lastname: Kim
authors.forename: Samuel
authors.initials: S
authors.lastname: Frank
authors.forename: Karl
authors.initials: K
authors.lastname: Kieburtz
mesh_terms: D001290:Attitude; D002986:Clinical Trials as Topic / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D010300:Parkinson Disease / Q000523:psychology* / Q000601:surgery*; D012107:Research Design; D011795:Surveys and Questionnaires