title: Explaining black-white differences in receipt of recommended colon cancer treatment.
abstract: BACKGROUND
  Black-white disparities exist in receipt of recommended medical care, including colorectal cancer treatment. This retrospective cohort study examines the degree to which health systems (e.g., physician, hospital) factors explain black-white disparities in colon cancer care.
  
  
  METHODS
  Data from the Surveillance, Epidemiology, and End Results program; Medicare claims; the American Medical Association Masterfile; and hospital surveys were linked to examine chemotherapy receipt after stage III colon cancer resection among 5294 elderly (> or = 66 years of age) black and white Medicare-insured patients. Logistic regression analysis was used to identify factors associated with black-white differences in chemotherapy use. All statistical tests were two-sided.
  
  
  RESULTS
  Black and white patients were equally likely to consult with a medical oncologist, but among patients who had such a consultation, black patients were less likely than white patients (59.3% versus 70.4%, difference = 10.9%, 95% confidence interval [CI] = 5.1% to 16.4%, P < .001) to receive chemotherapy. This black-white disparity was highest among patients aged 66-70 years (black patients 65.7%, white patients 86.3%, difference = 20.6%, 95% CI = 10.7% to 30.4%, P < .001) and decreased with age. The disparity among patients aged 66-70 years also remained statistically significant in the regression analysis. Overall, patient, physician, hospital, and environmental factors accounted for approximately 50% of the disparity in chemotherapy receipt among patients aged 66-70 years; surgical length of stay and neighborhood socioeconomic status accounted for approximately 27% of the disparity in this age group, and health systems factors accounted for 12%.
  
  
  CONCLUSIONS
  Black and white Medicare-insured colon cancer patients have an equal opportunity to learn about adjuvant chemotherapy from a medical oncologist but do not receive chemotherapy equally. Little disparity was explained by health systems; more was explained by illness severity, social support, and environment. Further qualitative research is needed to understand the factors that influence the lower receipt of chemotherapy by black patients.
authors.affiliation: Department of Family Medicine, University of Washington, Seattle, WA 98195-4982, USA. lmb@fammed.washington.edu
authors.forename: Laura-Mae
authors.initials: LM
authors.lastname: Baldwin
authors.forename: Sharon A
authors.initials: SA
authors.lastname: Dobie
authors.forename: Kevin
authors.initials: K
authors.lastname: Billingsley
authors.forename: Yong
authors.initials: Y
authors.lastname: Cai
authors.forename: George E
authors.initials: GE
authors.lastname: Wright
authors.forename: Jason A
authors.initials: JA
authors.lastname: Dominitz
authors.forename: William
authors.initials: W
authors.lastname: Barlow
authors.forename: Joan L
authors.initials: JL
authors.lastname: Warren
authors.forename: Stephen H
authors.initials: SH
authors.lastname: Taplin
mesh_terms: D001741:Black or African American / Q000706:statistics & numerical data*; D000368:Aged; D000369:Aged, 80 and over; D017024:Chemotherapy, Adjuvant / Q000706:statistics & numerical data*; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000188:drug therapy / Q000601:surgery / Q000628:therapy*; D015897:Comorbidity; D005260:Female; D006297:Health Services Accessibility / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay; D008297:Male; D006278:Medicare; D016017:Odds Ratio; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012307:Risk Factors; D018426:SEER Program; D012720:Severity of Illness Index; D012944:Social Support; D012959:Socioeconomic Factors; D014481:United States; D044465:White People / Q000706:statistics & numerical data*