Table 1.
Demographics of the study population.
| Years to index date | Training set | N | Age, mean (SD) | Encounters, mean (SD) | Cases, n (%) | Females, n (%) |
| 0 | Matched training | 680,945 | 74.3 (10.5) | 30.5 (28.2) | 136,189 (20.00) | 417,390 (61.30) |
| 3 | Matched training | 197,430 | 71.4 (10.2) | 24.4 (21.9) | 39,486 (20.00) | 121,015 (61.30) |
| 4 | Matched training | 130,270 | 70.4 (10.0) | 22.5 (20.3) | 26,054 (20.00) | 79,795 (61.25) |
| 5 | Matched training | 82,105 | 69.5 (9.8) | 20.4 (18.8) | 16,421 (20.00) | 50,300 (61.26) |
| 6 | Matched training | 47,555 | 68.6 (9.5) | 18.3 (16.8) | 9511 (20.00) | 29,620 (62.29) |
| 7 | Matched training | 23,455 | 67.6 (9.3) | 16.6 (16.1) | 4691 (20.00) | 14,630 (62.37) |
| 8 | Matched training | 7870 | 66.6 (9.1) | 16.2 (15.8) | 1574 (20.00) | 4885 (62.07) |
| 0 | Validation | 498,935 | 62.4 (11.3) | 21.0 (21.8) | 20,717 (4.15) | 292,683 (58.66) |
| 3 | Validation | 98,890 | 62.1 (10.8) | 18.5 (17.9) | 6525 (6.60) | 60,560 (61.24) |
| 4 | Validation | 61,471 | 61.7 (10.6) | 17.4 (17.0) | 4362 (7.10) | 37,909 (61.67) |
| 5 | Validation | 36,316 | 61.3 (10.4) | 16.2 (15.9) | 2763 (7.61) | 22,464 (61.86) |
| 6 | Validation | 18,888 | 61.0 (10.2) | 15.2 (15.0) | 1604 (8.49) | 11,776 (62.35) |
| 7 | Validation | 8186 | 60.6 (10.0) | 14.2 (14.4) | 806 (9.85) | 5122 (62.57) |
| 8 | Validation | 2660 | 60.0 (9.8) | 14.0 (13.7) | 292 (10.98) | 1694 (63.68) |
| 0 | Test | 1,000,448 | 62.3 (11.3) | 21.0 (21.7) | 41,642 (4.16) | 587,326 (58.71) |
| 3 | Test | 198,074 | 62.1 (10.8) | 18.5 (18.0) | 13,064 (6.60) | 122,003 (61.59) |
| 4 | Test | 122,939 | 61.7 (10.6) | 17.4 (16.9) | 8810 (7.17) | 75,996 (61.82) |
| 5 | Test | 72,304 | 61.3 (10.5) | 16.1 (15.7) | 5561 (7.69) | 44,926 (62.13) |
| 6 | Test | 37,938 | 61.0 (10.3) | 14.9 (14.3) | 3248 (8.56) | 23,709 (62.49) |
| 7 | Test | 16,487 | 60.8 (10.2) | 14.1 (13.5) | 1673 (10.15) | 10,465 (63.47) |
| 8 | Test | 5382 | 60.5 (10.1) | 13.9 (13.8) | 586 (10.89) | 3474 (64.55) |