Table 2.
LDL-c Control (1 = In control; 0 = Not in Control)
| Probit (Difference-in-Differences Analysis) | Bivariate Probit (IV Analysis) | |||
|---|---|---|---|---|
| Used mail order pharmacy to refill statin | 0.4475*** | (0.0173) | 0.3865*** | (0.0854) |
| Post period | 1.9908*** | (0.0126) | n/a | n/a |
| Length of follow-up | −0.0004*** | (0.0000) | −0.0009*** | (0.0000) |
| Total statin days supply | 0.0024*** | (0.0000) | 0.0033*** | (0.0000) |
| Gender: female | −0.3330*** | (0.0094) | −0.1958*** | (0.0096) |
| Age at statin initiation | 0.0121*** | (0.0004) | 0.0092*** | (0.0004) |
| African American | −0.0578** | (0.0195) | −0.0599** | (0.0193) |
| Asian | 0.1241*** | (0.0153) | 0.1212*** | (0.0160) |
| Latino | 0.1121*** | (0.0177) | 0.0778*** | (0.0180) |
| Native American | 0.1858** | (0.0652) | 0.1166 | (0.0675) |
| Mixed Race | 0.0865*** | (0.0242) | 0.0299 | (0.0247) |
| Race Missing | −0.0520*** | (0.0137) | −0.0438** | (0.0136) |
| Block Group Census | ||||
| Mean household income | 0.0000 | (0.0000) | 0.0000 | (0.0000) |
| Percent in poverty | 0.0022* | (0.0010) | 0.0016 | (0.0010) |
| % with high school education | −0.0009 | (0.0006) | −0.0010 | (0.0007) |
| % with at least a Bachelor’s degree | −0.0006 | (0.0005) | 0.0001 | (0.0005) |
| Number of comorbidities | 0.0625*** | (0.0057) | 0.0098 | (0.0059) |
| Has cardiovascular equivalents | −0.0520 | (0.0096) | −0.2014*** | (0.0097) |
| Using medication for depression | −0.0289* | (0.0116) | −0.0465*** | (0.0118) |
| Using non-formulary medication | −0.4048*** | (0.0222) | −0.4524*** | (0.0212) |
| Index statin is brand-name | 0.3435*** | (0.0271) | 0.2496*** | (0.0277) |
| # of primary care visits in prior year | 0.0120*** | (0.0011) | 0.0076*** | (0.0011) |
| Medicare Part D group coverage | 0.1461*** | (0.0166) | 0.1580*** | (0.0184) |
| Medicare Part D individual coverage | 0.0816*** | (0.0159) | 0.0504* | (0.0206) |
| Constant | −2.5446*** | (0.0714) | −0.8286*** | (0.0753) |
| ρ (disturbance correlation) | n/a | n/a | −0.1568** | (0.0530) |
Notes: (1) table shows estimated coefficients with standard errors in parentheses; (2) models control for patient’s home medical facility (where KP walk-in pharmacy is located); (3) difference-in-differences analysis uses random effects on panel dataset where N = 99,702 and T = 2 (pre and post period)
*p-value < 0.05
**p-value < 0.01
***p-value < 0.001