title: Impact of visit copayments on outpatient mental health utilization by members of a health maintenance organization.
abstract: OBJECTIVE
  The authors examined the impact of increasing cost sharing on use of outpatient mental health services.
  
  
  METHODS
  A quasi-experimental design was used to study outpatient utilization by members of a health maintenance organization (HMO) who were subject to increasing copayments for mental health visits (state government employees and dependents). Their outpatient mental health utilization was compared with that of similar HMO members who were not subject to cost sharing (federal government employees and dependents). Analyses compared both likelihood of any service use and number of visits per year among service users.
  
  
  RESULTS
  Institution of $20/visit copayments was associated with a 16% decrease in likelihood of service use but no change in visit rate among service users. A subsequent copayment increase to $30/visit resulted in no significant change in likelihood of use but was associated with a 9% decrease in visits per year among those using services. The impact of the first copayment change on likelihood of using services did not vary according to level of clinical need (as measured by prior service use and psychotropic drug use).
  
  
  CONCLUSIONS
  In this staff-model HMO, modest visit copayments significantly reduced initial access to mental health treatment and had a smaller effect on treatment intensity. Copayments restricted access regardless of clinical need. Designers of mental health benefits must consider the impact of copayments on those with the greatest need for treatment.
authors.affiliation: Center for Health Studies, Group Health Cooperative of Puget Sound, Seattle, WA 98101-1448, USA.
authors.forename: G E
authors.initials: GE
authors.lastname: Simon
authors.forename: L
authors.initials: L
authors.lastname: Grothaus
authors.forename: M L
authors.initials: ML
authors.lastname: Durham
authors.forename: M
authors.initials: M
authors.lastname: VonKorff
authors.forename: C
authors.initials: C
authors.lastname: Pabiniak
mesh_terms: D000553:Ambulatory Care / Q000706:statistics & numerical data*; D001071:Appointments and Schedules; D001294:Attitude to Health; D003156:Community Mental Health Services / Q000706:statistics & numerical data*; D017047:Cost Sharing; D003669:Deductibles and Coinsurance; D005249:Fees and Charges; D006264:Health Benefit Plans, Employee; D018166:Health Care Reform; D006279:Health Maintenance Organizations / Q000191:economics*; D006801:Humans; D007345:Insurance Claim Review; D011336:Probability; D014481:United States; D014600:Utilization Review