Baseline characteristics of children in EMRALD, Jan. 1, 2014–Dec. 31, 2015, and the Ontario population of children aged 18 years or less as of Jan. 1, 2015
| Characteristic | No. (%) of children | Standardized difference | p value | |
|---|---|---|---|---|
| EMRALD cohort n = 31 272 | Ontario n = 2 824 213 | |||
| Age, yr | ||||
| ≤ 4 | 15 089 (48.2) | 591 178 (20.9) | 0.60 | < 0.001 |
| 5–9 | 6907 (22.1) | 774 140 (27.4) | 0.12 | |
| 10–14 | 5616 (18.0) | 783 517 (27.7) | 0.23 | |
| 15–18 | 3660 (11.7) | 675 378 (23.9) | 0.32 | |
| Sex | ||||
| Female | 15 476 (49.5) | 1 375 466 (48.7) | 0.02 | 0.006 |
| Male | 15 796 (50.5) | 1 448 747 (51.3) | 0.02 | |
| Neighbourhood income quintile* | ||||
| 1 (lowest) | 4255 (13.6) | 516 726 (18.3) | 0.13 | < 0.001 |
| 2 | 5979 (19.1) | 507 046 (18.0) | 0.03 | |
| 3 | 6818 (21.8) | 562 377 (19.9) | 0.05 | |
| 4 | 7047 (22.5) | 639 624 (22.6) | 0.00 | |
| 5 (highest) | 7018 (22.4) | 585 113 (20.7) | 0.04 | |
| Missing | 155 (0.5) | 13 327 (0.5) | 0.00 | |
| Rural* | ||||
| No | 26 199 (83.8) | 2 522 659 (89.3) | 0.16 | < 0.001 |
| Yes | 5073 (16.2) | 300 371 (10.6) | 0.16 | |
| Missing | 0 (0.0) | 1183 (0.04) | 0.03 | |
| Immigration status | ||||
| Child is immigrant | 523 (1.7) | 220 095 (7.8) | 0.29 | < 0.001 |
| Mother is immigrant | 3365 (10.8) | 524 378 (18.6) | 0.22 | < 0.001 |
| Ethnicity* | ||||
| General population | 29 976 (95.9) | 2 568 987 (91.0) | 0.20 | < 0.001 |
| Chinese | 847 (2.7) | 135 869 (4.8) | 0.11 | |
| South Asian | 442 (1.4) | 117 957 (4.2) | 0.17 | |
| Missing | 7 (0.02) | 1400 (0.05) | 0.01 | |
| Chronic disease | ||||
| Asthma | 3708 (11.9) | 547 603 (19.4) | 0.21 | < 0.001 |
| Diabetes | 76 (0.2) | 12 644 (0.4) | 0.03 | < 0.001 |
| Complex chronic or congenital condition | 1541 (4.9) | 114 769 (4.1) | 0.04 | < 0.001 |
Note: EMRALD = Electronic Medical Records Administrative data Linked Database.
↵* Missing data are due to missing/incorrect postal code or missing/wrong name in patient’s record.