Skip to main content

Table 1 Age-adjusted percent distribution of patient- and neighborhood-level characteristics by hospital type, females diagnosed with breast cancer, Northern Californiaa, 1996–2009

From: Representativeness of breast cancer cases in an integrated health care delivery system

Characteristic KPNC (N = 36,109) % Non-KPNC All (N = 112,244) %
All other hospitals (N = 68,330) % Cancer centers (N = 7805) %
Race
 Non-Hispanic white 70.6 74.4 71.1 73.0
 Non-Hispanic black 8.1 5.0 6.5 6.0
 Hispanic 7.5 7.0 5.4 7.0
 Asian/Pacific Islander 13.0 12.6 16.0 13.0
 Non-Hisp Am Indian/Alas Native 0.3 0.3 0.2 0.3
 Other/unknown 0.6 0.7 0.7 0.6
Age at diagnosis
 < 30 0.3 0.4 0.8 0.4
 30–39 3.6 4.6 7.2 4.5
 40–49 16.9 18.9 23.1 18.5
 50–59 26.1 24.3 27.5 25.1
 60–69 25.3 20.6 20.4 22.1
 70–79 19.0 19.1 13.7 18.7
 80–89 7.8 10.6 6.5 9.4
 90+ 0.9 1.6 0.7 1.3
Insurance/payment source
 Any public/Medicaid/military 2.5 24.8 28.9 17.9
 Private only 92.4 52.7 55.1 65.7
 Other (none, Medicare, unknown) 3.3 22.5 16.0 16.4
AJCC stage
In situ 17.0 19.3 22.1 18.7
 Stage I 41.6 38.9 36.9 39.6
 Stage II 29.7 28.3 26.7 28.6
 Stage III 5.8 6.6 6.7 6.3
 Stage IV 3.2 3.4 4.6 3.4
 Unknown 2.7 3.6 3.1 3.3
Tumor size
 < 1 cm 20.0 20.0 23.4 20.2
 1–< 2 cm 34.9 32.4 31.2 33.1
 2–< 3 cm 18.5 16.9 15.0 17.3
 3–< 4 cm 7.8 7.3 7.5 7.4
 4+ cm 8.7 10.7 12.6 10.2
 Other 3.2 3.3 2.9 3.2
 Unknown 6.8 9.5 7.4 8.5
Lymph node involvement
 No nodal involvement 71.1 71.4 71.4 71.3
 Positive nodes 25.5 24.9 24.3 25.1
 Unknown 3.4 3.7 4.3 3.6
Histology
 Ductal 73.2 76.0 72.0 74.8
 Lobular 17.2 14.3 16.3 15.4
 Other 9.6 9.7 11.7 9.8
Neighborhood SESb
 Quintile 1 (lowest) 4.2 6.5 3.5 5.5
 Quintile 2 11.3 11.1 7.2 10.8
 Quintile 3 19.2 18.1 13.7 18.1
 Quintile 4 29.1 25.4 22.5 26.4
 Quintile 5 (highest) 36.2 39.0 53.2 39.1
% below povertyc
 0–4.9 % 45.9 45.5 45.8 45.7
 5.0–9.9 % 26.8 25.3 27.5 26.0
 10.0–19.9 % 19.2 19.0 17.4 18.9
 ≥ 20 % 8.1 10.2 9.5 9.5
Urban/rural
 Rural 4.6 6.9 4.9 6.0
 Small towns 1.6 3.2 1.2 2.6
 Small and medium size cities 29.2 29.4 7.6 27.8
 Suburban metropolitan areas 53.5 48.9 57.7 51.1
 Urban metropolitan areas 11.1 11.5 28.6 12.5
Population densityb
 Quartile 1 (low density) 23.7 26.9 22.4 25.6
 Quartile 2 31.2 31.1 25.5 30.8
 Quartile 3 26.8 24.2 19.0 24.7
 Quartile 4 (high density) 18.3 17.8 33.1 18.9
Hispanic ethnic enclaveb
 Quintile 1 (low enclave) 22.7 25.1 24.8 24.3
 Quintile 2 29.5 29.4 30.5 29.4
 Quintile 3 27.6 24.7 25.7 25.7
 Quintile 4 15.4 14.8 14.6 14.9
 Quintile 5 (high enclave) 4.8 5.7 4.2 5.3
 Unknown 0.3 0.3 0.1 0.3
Asian ethnic enclaveb
 Quintile 1 (low enclave) 7.1 9.3 5.3 8.3
 Quintile 2 16.2 16.9 13.3 16.5
 Quintile 3 21.6 21.7 19.4 21.5
 Quintile 4 24.9 24.0 23.5 24.3
 Quintile 5 (high enclave) 29.8 27.8 38.4 29.2
 Unknown 0.3 0.3 0.1 0.3
% Hispanic populationb
 < 9 % 38.5 43.1 57.6 42.7
 9–20 % 36.5 31.1 27.4 32.6
 21–47 % 20.1 19.2 11.9 19.0
 > 47 % 4.9 6.5 3.1 5.8
% non-Hispanic Asian populationb
 < 2 % 9.1 11.4 6.4 10.3
 2–4 % 22.4 22.4 16.1 22.0
 5–12 % 29.0 29.0 28.2 29.0
 > 12 % 39.5 37.2 49.3 38.7
% non-Hispanic White populationb
 < 23 % 12.1 10.9 10.4 11.2
 23–53 % 26.6 24.2 24.7 25.0
 54–75 % 31.7 31.4 30.3 31.4
 > 75 % 29.6 33.5 34.5 32.3
% non-Hispanic Black populationb
 0 % 20.7 25.8 25.7 24.2
 0.1–1.8 % 23.0 24.9 26.6 24.4
 1.9–6 % 28.3 27.2 26.4 27.5
 > 6 % 28.0 22.1 21.4 23.9
  1. All comparisons are statistically different at p < .001 using Chi-squared tests with Bonferroni adjustment for multiple comparisons
  2. KPNC Kaiser Permanente Northern California
  3. aAll frequencies (except for age) are age-adjusted to the age distribution of all cases. Includes counties of Alameda, Amador, Contra Costa, El Dorado, Fresno, Madera, Marin, Napa, Placer, Sacramento, San Francisco, San Joaquin, San Mateo, Santa Clara, Solano, Sonoma, and Yolo
  4. bQuintiles or quartiles based on distribution of block groups in California; socioeconomic status based on composite of seven Census 2000 indicators for education, occupation, unemployment, household income, poverty, rent, and house values (Yost et al. [11]); Hispanic ethnic enclave based on Census data on linguistic isolation, English fluency, Spanish language use, Hispanic ethnicity, immigration history, and nativity; Asian ethnic enclave based on Census data on Asian/Pacific Islander race/ethnicity, language, nativity, and recency of immigration [16, 17, 19]
  5. cBased on cut-off values from Krieger et al. [20, 24]