Table 3.
Determinants of VBAC: Analysis Results from Different Models.
| Probit | Logit | Mixed I | Mixed II | |
|---|---|---|---|---|
| Policy | 0.26 *** | 0.596 ** | 0.445 *** | 0.740 *** |
| (2.31) | (2.24) | (2.99) | (5.37) | |
| Patient Characteristics | ||||
| Age | 0.017 * | 0.037 * | 0.021 * | 0.021 * |
| (2.31) | (2.39) | (2.33) | (2.22) | |
| Income | −0.093 *** | −0.209 *** | −0.102 *** | −0.115 *** |
| (−3.67) | (−3.14) | (−3.32) | (−2.88) | |
| Complications | −0.211 *** | −0.543 *** | −0.075 | −0.107 |
| (−3.36) | 3.90) | (−0.92) | (−1.28) | |
| Fertility | 0.393 *** | 0.797 *** | 0.613 *** | 0.631 *** |
| (7.38) | (7.15) | (10.08) | (10.03) | |
| Institution Classification | ||||
| Medical center | 0.290 * | 0.608 * | 0.573 * | 0.471 ** |
| (2.54) | (2.51) | (2.36) | (2.92) | |
| Clinic | −0.775 | −1.784 | −0.547 | −0.784 |
| (−1.47) | (−1.54) | (−0.73) | (−1.07) | |
| Regional_H | −0.055 | −0.121 | 0.213 | −0.006 |
| (−0.55) | (−0.56) | −1.14 | (−0.04) | |
| Market Share | −0.418 | −0.795 | −0.82 | −0.162 |
| (−0.72) | (−0.64) | (−0.99) | (−0.19) | |
| Institution Ownership | ||||
| Conglomerate | −0.168 | −0.349 | −0.325 | −0.308 * |
| (−1.65) | (−1.60) | (−1.39) | (−3.01) | |
| Public | −0.102 | −0.224 | −0.221 | −0.184 |
| (−0.78) | (−0.81) | (−0.85) | (−0.99) | |
| Religion | 0.289 | 0.614 | 0.466 | 0.4 |
| (1.51) | (1.51) | (1.06) | (1.47) | |
| Districts | ||||
| Taipei | 0.179 | 0.378 | 0.155 | 0.219 |
| (0.83) | (0.81) | (0.50) | (0.66) | |
| Central | −0.128 | −0.258 | −0.037 | −0.169 |
| (−0.50) | (−0.46) | (−0.10) | (−0.43) | |
| East | 0.087 | 0.169 | −0.02 | 0.142 |
| −0.33 | −0.29 | (−0.05) | −0.36 | |
| Kao-ping | 0.482 * | 1.006 * | 0.391 | 0.591 |
| (2.20) | (2.13) | (1.23) | (1.77) | |
| South | 0.139 | 0.287 | 0.177 | 0.185 |
| (0.66) | (0.63) | (0.59) | (0.57) | |
| Doc. Characteristics | ||||
| Ob_age | 0.012 ** | 0.026 ** | 0.013 * | 0.012 * |
| (2.32) | (2.37) | (1.74) | (1.81) | |
| Female | −0.018 | −0.025 | 0.033 | −0.073 |
| (−0.15) | (−0.10) | (0.20) | (−0.47) | |
| Doc. Vol | 0.003 | 0.006 | 0.001 | 0.005 |
| (0.80) | (0.75) | (0.15) | (0.93) | |
| Other factors | ||||
| Weekend Adm. | 0.155 * | 0.324 * | 0.201 * | 0.204 * |
| (2.46) | (2.44) | (2.40) | (2.44) | |
| Time Trend | −0.065 *** | −0.130 *** | −0.096 *** | −0.000 *** |
| (−3.39) | (−3.18) | (−3.51) | (−3.04) | |
| Random Effect | ||||
| Zip Code | 0.00 | |||
| (0.17) | ||||
| Institution | 0.82 *** | 1.02 *** | ||
| (11.07) | (8.09) | |||
| Constant | 146.710 *** | 308.606 *** | 191.084 *** | 194.128 *** |
| (4.84) | (4.83) | (4.69) | (4.68) | |
| Obs no. | 34,914 | 34,914 | 34,914 | 34,882 |
| Chi2 | 145.59 | 150.84 | 185.575 | 202.32 |
| AIC | 6754.82 | 6747.45 | 6912.39 | 7041.78 |
| BIC | 6966.33 | 6958.97 | 7123.91 | 7261.73 |
Note: The omitted reference for institution classification is “district hospital”. The omitted region is the “North”. Market share is the Herfindahl-Hirschman index calculated based on the number of babies delivered in the year. Coefficients for logit and mixed models are log odds ratios. Numbers in parentheses are z-values. *, **, *** represent the 0.10, 0.05, and 0.01 statistical significance level, respectively.