Table 3.
Trend of Racial and Ethnic Disparities in the Use of New Drugs in First 5 Years of Marketing*
| Variables | Coefficient | RR†; | Robust Standard Error | t | p>|t| |
|---|---|---|---|---|---|
| Constant | −2.47 | N/A | 0.09 | −27.48 | .000 |
| Non-Hispanic whites | |||||
| Non-Hispanic blacks | −0.27 | 0.76 | 0.04 | −6.72 | .000 |
| Hispanic whites | −0.14 | 0.87 | 0.05 | −3.02 | .003 |
| Five-year criterion | |||||
| Four-year criterion | −0.48 | 0.62 | 0.01 | −44.30 | .000 |
| Three-year criterion | −0.91 | 0.40 | 0.02 | −52.27 | .000 |
| Two-year criterion | −1.49 | 0.23 | 0.02 | −64.69 | .000 |
| One-year criterion | −2.38 | 0.09 | 0.03 | −68.36 | .000 |
| Non-Hispanic blacks × 4-year criterion | −0.02 | 0.98 | 0.03 | −0.66 | .511 |
| Non-Hispanic blacks × 3-year criterion | −0.03 | 0.97 | 0.05 | −0.67 | .501 |
| Non-Hispanic blacks × 2-year criterion | −0.03 | 0.97 | 0.06 | −0.53 | .597 |
| Non-Hispanic blacks × 1-year criterion | −0.08 | 0.92 | 0.09 | −0.90 | .371 |
| Hispanic whites × 4-year criterion | −0.01 | 0.99 | 0.03 | −0.32 | .751 |
| Hispanic whites × 3-year criterion | −0.04 | 0.96 | 0.04 | −0.87 | .387 |
| Hispanic whites × 2-year criterion | 0.08 | 1.08 | 0.06 | 1.31 | .190 |
| Hispanic whites × 1-year criterion | 0.10 | 1.10 | 0.09 | 1.10 | .271 |
| Age (years) | 0.02 | 1.02 | 0.00 | 23.64 | .000 |
| Female | |||||
| Male | 0.01 | 1.01 | 0.03 | 0.49 | .624 |
| Unmarried | |||||
| Married | −0.08 | 0.92 | 0.03 | −2.52 | .012 |
| Lower than high school education | |||||
| High school diploma | 0.09 | 1.09 | 0.04 | 2.24 | .025 |
| Bachelor's degree | 0.16 | 1.17 | 0.06 | 2.84 | .005 |
| Master's degree or higher | 0.22 | 1.25 | 0.06 | 3.56 | .000 |
| Census region “Northeast” | |||||
| Census region “Midwest” | −0.01 | 0.99 | 0.04 | −0.34 | .731 |
| Census region “South” | 0.15 | 1.16 | 0.04 | 3.88 | .000 |
| Census region “West” | −0.36 | 0.70 | 0.05 | −6.63 | .000 |
| Nonmetropolitan statistical area | |||||
| Metropolitan statistical area | −0.09 | 0.91 | 0.04 | −2.47 | .013 |
| Negative income or poor‡; | |||||
| Near poor | −0.10 | 0.91 | 0.08 | −1.31 | .190 |
| Low income | 0.06 | 1.06 | 0.06 | 1.01 | .314 |
| Middle income | 0.04 | 1.04 | 0.05 | 0.83 | .406 |
| High income | 0.11 | 1.11 | 0.05 | 2.14 | .033 |
| Generosity of prescription drug benefit§ | 0.82 | 2.27 | 0.04 | 18.49 | .000 |
| Self-perceived excellent health status | |||||
| Self-perceived very good health status | 0.21 | 1.24 | 0.05 | 4.29 | .000 |
| Self-perceived good health status | 0.43 | 1.54 | 0.05 | 8.16 | .000 |
| Self-perceived fair health status | 0.59 | 1.81 | 0.06 | 9.69 | .000 |
| Self-perceived poor health status | 0.58 | 1.79 | 0.07 | 8.14 | .000 |
| Number of other medical conditions | 0.02 | 1.02 | 0.00 | 19.92 | .000 |
| Number of other prescription medications | 0.09 | 1.09 | 0.01 | 13.54 | .000 |
| Number of office-based physician visits | 0.02 | 1.02 | 0.00 | 9.85 | .000 |
*
The point estimate and the 99% confidence interval for dispersion parameter α are 2.05 [2.01–2.09].
†
Rate ratio.
‡
Categories of poverty status: negative income or poor: < 100% of poverty line; near poor: 100 to < 125% of poverty line; low income: 125 to < 200%; middle income: 200 to < 400%; wealthy: 400% and greater.
§
Generosity of drug benefit: share of annual drug cost paid by insurance.