Table 1. Baseline Characteristics of Physicians and Nonphysicians at Age 15 Years.
| Characteristic | No. (%) | Standardized difference | |
|---|---|---|---|
| Physicians (n = 5328) | Nonphysicians (n = 26 640) | ||
| Age at index date, median (IQR), y | 15 (15-15) | 15 (15-15) | 0 |
| Era of cohort entry | |||
| 1995-2006 | 2750 (51.6) | 13 750 (51.6) | 0 |
| 2007-2018 | 2578 (48.4) | 12 890 (48.4) | |
| Residential income urban quintile | |||
| 1 (Lowest) | 445 (8.4) | 4231 (15.9) | 0.23 |
| 2 | 548 (10.3) | 4256 (16.0) | 0.17 |
| 3 | 733 (13.8) | 4533 (17.0) | 0.09 |
| 4 | 1094 (20.5) | 4709 (17.7) | 0.07 |
| 5 (Highest) | 2092 (39.3) | 4653 (17.5) | 0.50 |
| Rural residence | 390 (7.3) | 4141 (15.5) | 0.26 |
| Missing | 26 (0.5) | 117 (0.4) | 0.01 |
| Immigration status | |||
| Canadian-born | 4517 (84.8) | 23 969 (90.0) | 0.16 |
| Immigrant | 881 (15.2) | 2671 (10.0) | |
| Comorbidities (Johns Hopkins ADGs) | |||
| 0 | 757 (14.2) | 3750 (14.1) | 0 |
| 1-5 | 3707 (69.9) | 18 121 (68.0) | 0.03 |
| 6-9 | 797 (15.0) | 4157 (15.6) | 0.02 |
| ≥10 | 67 (1.3) | 612 (2.3) | 0.08 |
| Previous live births | |||
| 0 | 5328 (100.0) | 26 612 (99.9) | 0.04 |
| 1 | 0 | 28 (0.1) | 0.04 |
| ≥2 | 0 | ||
Abbreviations: ADG, Aggregated Diagnosis Group; IQR, interquartile range.