title: What motivates Parkinson's disease patients to enter clinical trials?
abstract: BACKGROUND
  Limited data is available regarding motivations and concerns of Parkinson's disease (PD) patients when participating in clinical trials (CTs). Knowledge of these factors may improve the recruitment and quality of future trials.
  
  
  OBJECTIVE
  To assess the motivations and concerns of PD patients concerning participation in CTs and to evaluate the extent to which patients understand informed consent materials and placebo effect concept.
  
  
  METHODS
  Cross-sectional study in PD patients enrolled in CTs between 2002 and 2007. Two questionnaires designed for placebo-controlled and active-controlled studies were mailed to patients.
  
  
  RESULTS
  From the 93/127 replied questionnaires (response rate: 73.2%) 91 were evaluable. Fifty-nine percent of the participants were women with a mean age of 66.8 years. The main reasons for participating in CTs were to help the advance of science (63.7%), to gain access to a better treatment (56.0%), and to benefit others (51.6%). Risk of adverse events (49.5%) and negative effects of treatment (35.2%) were the major concerns. Ninety percent reported they had understood the informed consent. Of 80 patients included in placebo-controlled studies, 63.9% understood the placebo effect concept. Globally, 66% of patients would participate in another CT and 41.6% in a placebo-controlled trial.
  
  
  CONCLUSIONS
  The main motivations of PD patients to participate in CTs were the benefit to the patient himself and to others. The major concern was safety. PD patients understood the informed consent, but more educational efforts must be made to explain the placebo effect. Most PD patients were very positive toward CTs and would participate in another trial.
authors.affiliation: Department of Neurosciences, Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Lisbon, Portugal.
authors.forename: Anabela
authors.initials: A
authors.lastname: Valadas
authors.forename: Miguel
authors.initials: M
authors.lastname: Coelho
authors.forename: Tiago
authors.initials: T
authors.lastname: Mestre
authors.forename: Leonor Correia
authors.initials: LC
authors.lastname: Guedes
authors.forename: Maria
authors.initials: M
authors.lastname: Finisterra
authors.forename: Ana
authors.initials: A
authors.lastname: Noronha
authors.forename: Mário M
authors.initials: MM
authors.lastname: Rosa
authors.forename: Cristina
authors.initials: C
authors.lastname: Sampaio
authors.forename: Joaquim J
authors.initials: JJ
authors.lastname: Ferreira
mesh_terms: D000368:Aged; D002986:Clinical Trials as Topic; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D007258:Informed Consent; D008297:Male; D009042:Motivation; D010300:Parkinson Disease / Q000523:psychology*; D018579:Patient Selection; D011795:Surveys and Questionnaires