title: How do clinical trial participants compare to other patients with schizophrenia?
abstract: OBJECTIVE
  Patients with schizophrenia enrolled in a trial of long-acting injectable risperidone at multiple sites of the Veterans Health Administration (VHA). We considered if the trial participants were representative of the targeted group of high-utilization patients with poor adherence to anti-psychotics.
  
  
  METHODS
  Participants' characteristics, health services utilization, and cost in the year prior to randomization were compared to a randomly selected time-matched cohort of 10,000 other patients with schizophrenia who were not in the trial.
  
  
  RESULTS
  There were few differences in the characteristics, utilization, or cost between trial participants and non-participants who met the key trial inclusion criterion of a history of psychiatric hospitalization in the prior 24 months. Trial participants were more likely to be African-American (45.5% vs. 35.1%, p<.001) and were less likely to have had a medical-surgical hospitalization in the study year (8.2% vs. 19.2% p<.001). Compared to non-participants who did not meet the inclusion criterion, trial participants were more likely to have a psychiatric condition in addition to schizophrenia (81.0% vs. 51.3%, p<.001), more likely to have a substance abuse disorder (46.3% vs. 13.9% p<.001), and less likely to be adherent with their anti-psychotic medication (21.3% vs. 37.9%, p<.001). They also incurred more than three times the annual cost ($42,563 vs. $12,270, p<.001).
  
  
  CONCLUSIONS
  Trial participants appeared to be representative of the 23.3% of VHA patients with schizophrenia who met the key trial inclusion criterion, suggesting that trial findings will be relevant to the broader group of high risk patients.
authors.affiliation: Health Economics Resource Center, VA Cooperative Studies Program, VA Palo Alto Health Care System, 795 Willow Road (152), Menlo Park, CA 94025, USA. paul.barnett@va.gov
authors.forename: Paul G
authors.initials: PG
authors.lastname: Barnett
authors.forename: Jennifer Y
authors.initials: JY
authors.lastname: Scott
authors.forename: Robert A
authors.initials: RA
authors.lastname: Rosenheck
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000191:economics / Q000627:therapeutic use*; D002986:Clinical Trials as Topic / Q000191:economics / Q000379:methods*; D015331:Cohort Studies; D003365:Costs and Cost Analysis; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010349:Patient Compliance / Q000523:psychology / Q000706:statistics & numerical data; D018967:Risperidone / Q000191:economics / Q000627:therapeutic use*; D012559:Schizophrenia / Q000188:drug therapy* / Q000191:economics; D012565:Schizophrenic Psychology; D014481:United States; D014493:United States Department of Veterans Affairs
chemical_list: D014150:Antipsychotic Agents; D018967:Risperidone