title: When VA patients have non-VA hospitalizations, who pays for what services, and what are the research implications? A New York case study.
abstract: OBJECTIVE
  To determine, for Veterans Health Administration (VA) enrollees who lived and were hospitalized in New York State between 1998 and 2000, the primary payers for their non-VA admissions, whether the primary payer mix varied by condition treated, and whether the Medicare claims data that VA acquired on its Medicare-enrolled patients captured all or most of their non-VA inpatient care.
  
  
  METHODS
  Using VA and New York State administrative and clinical databases, we conducted a retrospective study examining 75,046 residents of New York State who were enrolled in the VA and had 159,843 inpatient admissions in New York hospitals not in the VA system. For each admission, we determined the major diagnostic category, the primary payer for the admission, and whether the patient was Medicare-enrolled. Our analyses separated veterans into those younger than age 65 and those ages 65 or older.
  
  
  RESULTS
  The payer mix for younger veterans' non-VA admissions varied considerably by major diagnostic category. Among veterans who also were Medicare enrollees, Medicare did not pay for 10% of the non-VA hospitalizations of older patients or 20% of those for younger patients.
  
  
  CONCLUSIONS
  Using only Medicare claims data may significantly underestimate VA patients' reliance on non-VA inpatient care. To better inform planners about VA's service market and diagnosis-specific service utilization patterns across VA and non-VA providers, VA should work with states to develop comprehensive inpatient datasets.
authors.affiliation: VA Outcomes Group Research Enhancement Award Program, White River Junction VA Medical Center, White River Junction, Vermont 05009, USA. alan.west@va.gov
authors.forename: Alan N
authors.initials: AN
authors.lastname: West
authors.forename: William B
authors.initials: WB
authors.lastname: Weeks
authors.forename: Steven M
authors.initials: SM
authors.lastname: Wright
authors.forename: Amy E
authors.initials: AE
authors.lastname: Wallace
authors.forename: Elliott S
authors.initials: ES
authors.lastname: Fisher
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003953:Diagnosis-Related Groups / Q000191:economics*; D005260:Female; D006760:Hospitalization / Q000191:economics*; D006801:Humans; D007345:Insurance Claim Review; D008297:Male; D006278:Medicare / Q000191:economics* / Q000706:statistics & numerical data; D008875:Middle Aged; D009518:New York; D014481:United States; D014493:United States Department of Veterans Affairs / Q000191:economics*; D014728:Veterans