title: Cancer care in the United States: identifying end-of-life cohorts.
abstract: OBJECTIVE
  End-of-life care is increasingly recognized as an important part of cancer management for many patients. Current methods to measure end-of-life care are limited by difficulties in identifying cancer cohorts with administrative data. We examined several techniques of identifying end-of-life cancer cohorts with claims data that is population-based, geographically scalable, and amenable to routine updating.
  
  
  METHODS
  Using Medicare claims for patients 65 years of age and older, four techniques for identifying end-of-life cancer cohorts were compared; one based on Part A data using a broad primary or narrow secondary diagnosis of cancer, two based on Part B data, and one combining the Part A and B methods. We tested the performance of each definition to ascertain an appropriate end-of-life cancer population.
  
  
  RESULTS
  The combined Part A and B definition using a primary or secondary diagnosis of cancer within a window of 180 days prior to death appears to be the most accurate and inclusive in ascertaining an end-of-life cohort (78.7% attainment).
  
  
  CONCLUSIONS
  Combining inpatient and outpatient claims data, and identifying cases based upon a broad primary or a narrow secondary cancer definition is the most accurate and inclusive in ascertaining an end-of-life cohort.
authors.affiliation: The Center for Healthcare Research and Reform, The Dartmouth Institute for Health Policy and Clinical Practice, Dartmouth Medical School, Hanover, New Hampshire, USA. ethan.m.berke@dartmouth.edu
authors.forename: Ethan M
authors.initials: EM
authors.lastname: Berke
authors.forename: Tenbroeck
authors.initials: T
authors.lastname: Smith
authors.forename: Yunjie
authors.initials: Y
authors.lastname: Song
authors.forename: Michael T
authors.initials: MT
authors.lastname: Halpern
authors.forename: David C
authors.initials: DC
authors.lastname: Goodman
mesh_terms: D000368:Aged; D015331:Cohort Studies; D006738:Hospices / Q000706:statistics & numerical data; D006801:Humans; D006278:Medicare; D009369:Neoplasms / Q000401:mortality / Q000628:therapy*; D013727:Terminal Care; D014481:United States / Q000453:epidemiology