title: Improving the delivery and organisation of mental health services: beyond the conventional randomised controlled trial.
abstract: BACKGROUND
  There is an ethical imperative to evaluate service and policy initiatives, such as those highlighted in the recent National Service Framework, just as there is to evaluate individual treatments.
  
  
  OBJECTIVE
  To outline the best methods available for evaluating the delivery and organisation of mental health services.
  
  
  METHODS
  We present a narrative methodological overview, using salient examples from mental health services research.
  
  
  RESULTS
  Cluster randomised studies involve the random allocation of groups of clinicians, clinical teams or hospitals rather than individual patients, and produce the least biased evaluation of mental health policy, organisation or service delivery. Where randomisation is impossible or impractical (often when services or policies are already implemented), then quasi-experimental designs can be used. Such designs have both strengths and many potential flaws.
  
  
  CONCLUSIONS
  The gold standard remains the randomised trial, but with due consideration to the unit of randomisation. Use of quasi-experimental designs can be justified in certain circumstances but should be attempted and interpreted with caution.
authors.affiliation: Academic Unit of Psychiatry and Behavioural Sciences, University of Leeds, Leeds LS2 9LT, UK. s.m.gilbody@leeds.ac.uk
authors.forename: Simon
authors.initials: S
authors.lastname: Gilbody
authors.forename: Paula
authors.initials: P
authors.lastname: Whitty
mesh_terms: D003695:Delivery of Health Care / Q000458:organization & administration / Q000592:standards*; D006302:Health Services Research / Q000379:methods*; D006801:Humans; D008605:Mental Health Services / Q000458:organization & administration / Q000592:standards*; D011785:Quality Assurance, Health Care / Q000458:organization & administration*; D016032:Randomized Controlled Trials as Topic / Q000379:methods; D012107:Research Design; D013222:State Medicine / Q000458:organization & administration / Q000592:standards; D006113:United Kingdom