title: Absence of association between insurance copayments and delays in seeking emergency care among patients with myocardial infarction.
abstract: BACKGROUND
  The requirement of copayments for emergency care is thought to control costs by reducing "inappropriate" visits to the emergency department. However, requiring copayments may lead to adverse outcomes if patients delay seeking care for emergency conditions. To determine whether such requirements are associated with delays in seeking care, we examined the length of time from the onset of symptoms to arrival at the hospital among patients with myocardial infarction who did or did not have required insurance copayments.
  
  
  METHODS
  All patients were enrolled in a single health maintenance organization (HMO) and presented with myocardial infarction at 1 of 19 hospitals in King County, Washington, from 1989 through 1994. There were 602 patients whose health insurance required a copayment for emergency department care (range, $25 to $100) and 729 patients with no copayment requirement. Data on the time to presentation were obtained from a review of ambulance and hospital records.
  
  
  RESULTS
  The median length of time from the onset of symptoms to arrival at the hospital, as adjusted for age, sex, and race, was 135 minutes for the copayment group and 137 minutes for the group with no copayment (95 percent confidence interval for the difference, -19 to +16 minutes). There was no significant association between the presence or absence of a copayment requirement and the time to arrival at the hospital after adjustment for calendar year, income, educational level, cardiac history, or clinical symptoms. Since some patients may be unaware of their copayment requirement, we performed a subgroup analysis of data on patients who had a previous visit to the emergency department with the same copayment status - that is, of patients who were likely to know about their copayment. This analysis also showed no significant association between the requirement for a copayment and delays in seeking treatment.
  
  
  CONCLUSIONS
  For privately insured patients in this HMO, the requirement of modest, fixed copayments for emergency services did not lead to delays in seeking treatment for myocardial infarction.
authors.affiliation: Clinical Research Unit, Colorado Permanente Medical Group, Denver 80231-1314, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Magid
authors.forename: T D
authors.initials: TD
authors.lastname: Koepsell
authors.forename: N R
authors.initials: NR
authors.lastname: Every
authors.forename: J S
authors.initials: JS
authors.lastname: Martin
authors.forename: D S
authors.initials: DS
authors.lastname: Siscovick
authors.forename: E H
authors.initials: EH
authors.lastname: Wagner
authors.forename: W D
authors.initials: WD
authors.lastname: Weaver
mesh_terms: D000328:Adult; D000368:Aged; D017047:Cost Sharing / Q000706:statistics & numerical data*; D003669:Deductibles and Coinsurance; D004636:Emergency Service, Hospital / Q000191:economics* / Q000706:statistics & numerical data*; D005260:Female; D006279:Health Maintenance Organizations; D006302:Health Services Research / Q000379:methods; D006323:Heart Arrest / Q000191:economics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000191:economics* / Q000628:therapy*; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data*; D013997:Time Factors; D014861:Washington