Table 2.
Negative Binomial Regression Predicting the Number of Practice Sites per Physician
| Estimate | SE | 95% LCLM | 95% UCLM | P Value | |
|---|---|---|---|---|---|
| Intercept | 1.1833 | 0.0159 | 1.1521 | 1.2144 | <.0001 |
| Age (years) | |||||
| <40 | 0.2884 | 0.0205 | 0.2482 | 0.3287 | <.0001 |
| 40–49 | 0.2704 | 0.0181 | 0.235 | 0.3058 | <.0001 |
| 50–59 | 0.1591 | 0.0189 | 0.122 | 0.1962 | <.0001 |
| ≥60 | Reference | ||||
| Sex | |||||
| Male | Reference | ||||
| Female | −0.1544 | 0.0139 | −0.1816 | −0.1273 | <.0001 |
| IMG status | |||||
| IMG | 0.0268 | 0.015 | −0.0026 | 0.0562 | .0735 |
| Non-IMG | Reference | ||||
| Present employment setting | |||||
| Self-employed solo practice | −0.4138 | 0.0225 | −0.4579 | −0.3696 | <.0001 |
| Two-physician practice | −0.32 | 0.0394 | −0.3973 | −0.2427 | <.0001 |
| Group practice | Reference | ||||
| Medical school | −0.0603 | 0.0457 | −0.1499 | 0.0293 | .1873 |
| State/local | −0.0749 | 0.0196 | −0.1132 | −0.0366 | .0001 |
| Federal | −0.1233 | 0.081 | −0.2819 | 0.0354 | .1279 |
| Others | −0.0662 | 0.0162 | −0.0979 | −0.0345 | <.0001 |
| Primary Specialty | |||||
| Non–primary care | Reference | ||||
| Primary care | −0.2781 | 0.0138 | −0.3052 | −0.2511 | <.0001 |
| Dispersion | 0.409 | 0.0066 | 0.3963 | 0.4221 |
A total of 19,451 cases were used; 665 cases were excluded because of missing values.
IMG, international medical graduate; LCLM, Lower Confidence Limit; SE, standard error; UCLM, Upper Confidence Limit.