Table 3.
Cox proportional hazard regression output with quintiles of Black, Hispanic, and other racialized populations
| Variable | Model 1a |
Model 2b |
Model 3c |
|||
|---|---|---|---|---|---|---|
| HR (95% CI) | P | HR (95% CI) | P | HR (95% CI) | P | |
| Percentage of Black population in a county quintile; referent: quintile 1 (lowest percentage) | ||||||
| 2 | 0.97 (0.89 to 1.06) | .48 | 0.95 (0.87 to 1.04) | .30 | 0.96 (0.88 to 1.05) | .33 |
| 3 | 0.93 (0.84 to 1.04) | .20 | 0.92 (0.83 to 1.02) | .10 | 0.92 (0.84 to 1.02) | .12 |
| 4 | 1.00 (0.91 to 1.09) | .91 | 0.97 (0.90 to 1.06) | .56 | 0.98 (0.90 to 1.06) | .57 |
| 5 (highest percentage) | 0.99 (0.92 to 1.08) | .89 | 0.99 (0.91 to 1.08) | .84 | 0.99 (0.90 to 1.08) | .79 |
| Percentage of Hispanic population in a county quintile; referent: quintile 1 (lowest percentage) | ||||||
| 2 | 1.01 (0.92 to 1.10) | .90 | 1.02 (0.94 to 1.10) | .69 | 1.02 (0.94 to 1.11) | .61 |
| 3 | 0.91 (0.83 to 1.00) | .04 | 0.91 (0.84 to 1.00) | .05 | 0.92 (0.84 to 1.01) | .07 |
| 4 | 0.94 (0.86 to 1.03) | .19 | 0.95 (0.86 to 1.04) | .24 | 0.95 (0.87 to 1.04) | .30 |
| 5 (highest percentage) | 0.73 (0.66 to 0.81) | <.001 | 0.74 (0.67 to 0.83) | <.001 | 0.75 (0.67 to 0.83) | <.001 |
| Percentage of other racialized population in a county quintile; referent: quintile 1 (lowest percentage) | ||||||
| 2 | 1.01 (0.92 to 1.10) | .17 | 1.06 (0.98 to 1.15) | .15 | 1.07 (0.98 to 1.17) | .14 |
| 3 | 1.03 (0.83 to 1.00) | .51 | 1.04 (0.96 to 1.13) | .34 | 1.05 (0.95 to 1.15) | .34 |
| 4 | 1.04 (0.86 to 1.03) | .49 | 1.01 (0.92 to 1.11) | .85 | 1.01 (0.92 to 1.12) | .80 |
| 5 (highest percentage) | 0.79 (0.66 to 0.81) | <.001 | 0.79 (0.70 to 0.89) | <.001 | 0.79 (0.70 to 0.90) | <.001 |
| Age group (referent: <55), y | ||||||
| 55 to younger than 65 | — | — | 1.05 (0.89 to 1.25) | .53 | 1.06 (0.89 to 1.25) | .53 |
| 65 to younger than 75 | — | — | 1.05 (0.89 to 1.25) | .57 | 1.05 (0.89 to 1.24) | .58 |
| 75 and older | — | — | 0.83 (0.69 to 0.99) | .04 | 0.83 (0.69 to 0.99) | .04 |
| Female (referent: male) | — | — | 0.84 (0.80 to 0.87) | <.001 | 0.84 (0.80 to 0.87) | <.001 |
| Charlson comorbidities (referent: 0) | ||||||
| 1-2 | — | — | 1.03 (0.96 to 1.10) | .43 | 1.03 (0.96 to 1.10) | .44 |
| ≥3 | — | — | 0.93 (0.87 to 0.99) | .02 | 0.93 (0.87 to 0.99) | .02 |
| Medicare Advantage | — | — | 0.83 (0.77 to 0.90) | <.001 | 0.83 (0.77 to 0.90) | <.001 |
| Urbanity (referent: metro) | ||||||
| Urban | — | — | — | — | 1.01 (0.93 to 1.11) | .76 |
| Rural | — | — | — | — | 1.14 (0.96 to 1.35) | .13 |
| No. medical oncologists per 100 000 | — | — | — | — | 1.00 (0.11 to 1.01) | .51 |
| Diagnosis year (referent: 2015) | ||||||
| 2016 | — | — | 1.35 (1.22 to 1.50) | <.001 | 1.35 (1.21 to 1.50) | <.001 |
| 2017 | — | — | 2.01 (1.83 to 2.21) | <.001 | 2.01 (1.83 to 2.21) | <.001 |
| 2018 | — | — | 2.78 (2.54 to 3.03) | <.001 | 2.77 (2.54 to 3.03) | <.001 |
| 2019 | — | — | 4.08 (3.73 to 4.47) | <.001 | 4.07 (3.72 to 4.46) | <.001 |
| 2020 | — | — | 4.93 (4.46 to 5.46) | <.001 | 4.92 (4.45 to 5.45) | <.001 |
a
Model 1 only included quintiles of percentage of racialized population, to estimate crude hazard ratios. CI = confidence interval; HR = hazard ratio.
b
Model 2 adjusted for patient characteristics (age, sex, Charlson comorbidity index, Medicare Advantage, and year of diagnosis) in addition to percentage of racialized population.
c
Model 3 further adjusted for urbanity and density of oncologists in addition to the variables included in model 2.