title: Contribution of treatment acceptability to acceptance of randomization: an exploration.
abstract: OBJECTIVE
  Randomization to treatment is viewed unfavourably by many trial participants. There is limited research that investigated factors contributing to acceptance of randomization. This study explored the influence of participants' socio-demographic and clinical characteristics, and their perceived acceptability of the treatments on their acceptance of randomization (i.e. willingness to be randomized) in a clinical trial.
  
  
  METHODS
  Persons with insomnia (n = 383) were asked about their acceptance of randomization before and after they rated the acceptability of behavioural therapies for managing insomnia (sleep education and hygiene booklet, stimulus control therapy and sleep restriction therapy). Socio-demographic and clinical characteristics, and treatment acceptability, were measured with established instruments. Logistic regression was applied to explore the association between participants' characteristics and treatment acceptability, and reported acceptance of randomization.
  
  
  RESULTS
  Prior to rating treatments' acceptability, 54.6% of participants were willing to be randomized; socio-demographic (age and ethnicity) and clinical (severity of insomnia's impact, state anxiety, depression, vitality and mental and social functions) contributed to acceptance of randomization. After rating the treatments' acceptability, 87.8% of participants were unwilling to be randomized; age, severity of insomnia's impact and acceptability of behavioural therapy were significantly associated with acceptance of randomization.
  
  
  CONCLUSIONS
  The study findings indicated that participants are likely to express unwillingness to be randomized once they receive treatment information and rate the acceptability of treatments. The reported non-acceptance may influence participants' behaviour (e.g. withdrawal, non-adherence) during the trial, suggesting the need to explore alternative designs for intervention evaluation.
authors.affiliation: School of Nursing, Ryerson University, Toronto, Ontario, Canada.
authors.forename: Souraya
authors.initials: S
authors.lastname: Sidani
authors.affiliation: School of Nursing, York University, Toronto, Ontario, Canada.
authors.forename: Mary
authors.initials: M
authors.lastname: Fox
authors.affiliation: Nursing Research and Evidence-Based Practice, Phoenix Veterans Affairs Health Care System, Phoenix, AZ, USA.
authors.forename: Dana R
authors.initials: DR
authors.lastname: Epstein
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001521:Behavior Therapy / Q000379:methods*; D005006:Ethnicity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010353:Patient Education as Topic / Q000379:methods; D011897:Random Allocation; D035842:Research Subjects / Q000523:psychology*; D012720:Severity of Illness Index; D007319:Sleep Initiation and Maintenance Disorders / Q000628:therapy*; D012959:Socioeconomic Factors
keywords: acceptance of randomization; behavioural therapy; insomnia; intervention research; treatment acceptability; willingness to be randomized