title: Racial disparities in colon cancer survival: a matched cohort study.
abstract: BACKGROUND
  Differences in colon cancer survival by race are a recognized problem among Medicare beneficiaries.
  
  
  OBJECTIVE
  To determine to what extent the racial disparity in survival is due to disparity in presentation characteristics at diagnosis or disparity in subsequent treatment.
  
  
  METHODS
  Black patients with colon cancer were matched with 3 groups of white patients: a "demographic characteristics" match controlling for age, sex, diagnosis year, and Survey, Epidemiology, and End Results (SEER) site; a "presentation" match controlling for demographic characteristics plus comorbid conditions and tumor characteristics, including stage and grade; and a "treatment" match, including presentation variables plus details of surgery, radiation, and chemotherapy.
  
  
  METHODS
  16 U.S. SEER sites.
  
  
  METHODS
  7677 black patients aged 65 years or older diagnosed between 1991 and 2005 in the SEER-Medicare database and 3 sets of 7677 matched white patients, followed until 31 December 2009.
  
  
  METHODS
  5-year survival.
  
  
  RESULTS
  The absolute difference in 5-year survival between black and white patients was 9.9% (95% CI, 8.3% to 11.4%; P<0.001) in the demographic characteristics match. This disparity remained unchanged between 1991 and 2005. After matching for presentation characteristics, the difference decreased to 4.9% (CI, 3.6% to 6.1%; P<0.001). After additional matching for treatment, this difference decreased to 4.3% (CI, 2.9% to 5.5%; P<0.001). The disparity in survival attributed to treatment differences made up only an absolute 0.6% of the overall 9.9% survival disparity.
  
  
  CONCLUSIONS
  An observational study limited to elderly Medicare fee-for-service beneficiaries living in selected geographic areas.
  
  
  CONCLUSIONS
  Racial disparities in colon cancer survival did not decrease among patients diagnosed between 1991 and 2005. This persistent disparity seemed to be more related to presentation characteristics at diagnosis than to subsequent treatment differences.
  
  
  BACKGROUND
  Agency for Healthcare Research and Quality and National Science Foundation.
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Silber
authors.forename: Paul R
authors.initials: PR
authors.lastname: Rosenbaum
authors.forename: Richard N
authors.initials: RN
authors.lastname: Ross
authors.forename: Bijan A
authors.initials: BA
authors.lastname: Niknam
authors.forename: Justin M
authors.initials: JM
authors.lastname: Ludwig
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Amy S
authors.initials: AS
authors.lastname: Clark
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Fox
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Orit
authors.initials: O
authors.lastname: Even-Shoshan
authors.forename: Bruce J
authors.initials: BJ
authors.lastname: Giantonio
mesh_terms: D001741:Black or African American / Q000706:statistics & numerical data*; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000175:diagnosis / Q000208:ethnology* / Q000401:mortality* / Q000628:therapy; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D006278:Medicare; D018426:SEER Program; D012959:Socioeconomic Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data*