Table 3.
Modified Poisson Regression Results for ODX Test Use for Patients With Node-Negative Breast Cancer
| Characteristic | Primary Model | Secondary Model | ||||
|---|---|---|---|---|---|---|
| RR | 95% CI | P | RR | 95% CI | P | |
| Black v non-black* | 0.91 | 0.76 to 1.094 | .33 | 0.95 | 0.78 to 1.15 | .58 |
| Tumor size v < 2 cm, cm | ||||||
| 2-5 | 1.30 | 1.083 to 1.56 | .005 | 1.31 | 1.10 to 1.56 | .003 |
| > 5 | 0.31 | 0.089 to 1.045 | .059 | 0.31 | 0.091 to 1.019 | .054 |
| Grade v 1 | ||||||
| 2 | 1.41 | 1.16 to 1.72 | .001 | 1.41 | 1.15 to 1.72 | .001 |
| 3 | 1.42 | 1.098 to 1.83 | .007 | 1.45 | 1.13 to 1.86 | .003 |
| PR positive v negative | 1.48 | 1.085 to 2.029 | .014 | 1.50 | 1.099 to 2.051 | .011 |
| Mastectomy v lumpectomy | 1.031 | 0.86 to 1.23 | .74 | 1.05 | 0.88 to 1.25 | .58 |
| No. of comorbidities | 0.91 | 0.83 to 1.011 | .080 | 0.95 | 0.86 to 1.060 | .38 |
| Age at diagnosis < 50 v > 50 years | 1.13 | 0.95 to 1.33 | .16 | 1.074 | 0.90 to 1.28 | .42 |
| Diagnosis year v 2008 | ||||||
| 2009 | 0.86 | 0.66 to 1.12 | .26 | 0.84 | 0.65 to 1.10 | .22 |
| 2010 | 0.84 | 0.66 to 1.072 | .16 | 0.78 | 0.60 to 1.00 | .052 |
| 2011 | 0.85 | 0.66 to 1.10 | .23 | 0.8 | 0.62 to 1.038 | .093 |
| 2012 or 2013 | 0.79 | 0.58 to 1.074 | .13 | 0.74 | 0.54 to 1.011 | .058 |
| Family income v < $15,000, $ | ||||||
| 15,000-30,000 | 0.97 | 0.66 to 1.43 | .89 | |||
| 30,000-50,000 | 1.12 | 0.77 to 1.62 | .56 | |||
| > 50,000 | 1.017 | 0.68 to 1.52 | .94 | |||
| Not reported | 0.64 | 0.39 to 1.069 | .088 | |||
| Uninsured v insured | 0.84 | 0.55 to 1.28 | .42 | |||
| Married v unmarried | 1.11 | 0.91 to 1.37 | .30 | |||
| Employment v unemployed | ||||||
| Employed | 1.068 | 0.89 to 1.29 | .48 | |||
| Not reported | 0.46 | 0.91 to 2.13 | .32 | |||
| Education v HS or v HS or higher | ||||||
| College or higher | 1.082 | 0.92 to 1.27 | .33 | |||
| Less than HS | 0.87 | 0.56 to 1.35 | .53 | |||
| Constant† | 0.30 | 0.19 to 0.47 | <.001 | 0.26 | 0.15 to 0.45 | < .001 |
NOTE. N = 1,049. The number of primary sampling units (ie, provider) used to account for provider-level clustering was 455. Population-weighted sample size = 3,641. Primary model covariates were tumor size, tumor grade, PR status, surgery type, number of comorbidities, age at diagnosis, and year of diagnosis. Additional secondary model covariates were family income, health insurance status, marital status, employment status, and education level.
Abbreviations: HS, high school; ODX, Oncotype DX (Genomic Health, Redwood City, CA); PR, progesterone receptor; RR, risk ratio.
Results for the crude model were RR, 0.90; 95% CI, 0.77 to 1.067; P = .23.
Results for the crude model were RR, 0.46; 95% CI, 0.41 to 0.51; P = < .001.