Table 1.
Estimated association between potential confounders and (i) inclusion in final adjusted model for alcohol patterns, (ii) CP trajectory class membership, (iii) alcohol frequency of use pattern.
| (i) In final adjusted model | (ii) CP trajectory class | (iii) Alcohol frequency of use pattern | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No | Yes | X2, p | Low | CL | AO | EOP | X2, p | Low freq | Medium freq | High freq | X2, p | |
| Parity | ||||||||||||
| 1st born | 1025 (31.1%) | 2270 (68.9%) | X2 = 4.69 p = 0.096 | 2322 (70.5%) | 377 (11.4%) | 302 (9.2%) | 294 (8.9%) | X2 = 12.0 p = 0.061 | 1668 (62.6%) | 763 (28.6%) | 233 (8.8%) | X2 = 45.1 p < 0.001 |
| 2nd born | 799 (31.8%) | 1712 (68.2%) | 1776 (70.7%) | 310 (12.4%) | 207 (8.2%) | 218 (8.7%) | 1090 (56.0%) | 595 (30.6%) | 261 (13.4%) | |||
| 3rd or greater | 424 (34.5%) | 806 (65.5%) | 845 (68.7%) | 159 (12.9%) | 90 (7.3%) | 136 (11.1%) | 500 (54.0%) | 296 (32.0%) | 130 (14.0%) | |||
| Maternal education | ||||||||||||
| A-level or higher | 816 (26.6%) | 2254 (73.4%) | X2 = 133.4 p < 0.001 | 2250 (73.3%) | 334 (10.9%) | 256 (8.3%) | 230 (7.5%) | X2 = 49.6 p < 0.001 | 1503 (59.2%) | 768 (30.2%) | 270 (10.6%) X2 = 8.10 p = 0.088 | |
| O-level | 813 (32.4%) | 1694 (67.6%) | 1764 (70.4%) | 303 (12.1%) | 213 (8.5%) | 227 (9.1%) | 1180 (60.1%) | 547 (27.8%) | 238 (12.1%) | |||
| <O-level | 650 (43.6%) | 840 (56.4%) | 960 (64.4%) | 212 (14.2%) | 130 (8.7%) | 188 (12.6%) | 597 (56.3%) | 334 (31.5%) | 129 (12.2%) | |||
| Gender | ||||||||||||
| Male | 1285 (35.3%) | 2352 (64.7%) X2 = 9.11 p = 0.003 | 2478 (68.1%) | 474 (13.0%) | 306 (8.4%) | 379 (10.4%) | X2 = 20.6 p < 0.001 | 1681 (60.3%) | 792 (28.4%) | 313 (11.2%) | X2 = 5.25 p = 0.072 | |
| Female | 1145 (31.2%) | 2436 (68.0%) | 2583 (72.1%) | 401 (11.2%) | 310 (8.7%) | 287 (8.0%) | 1652 (57.5%) | 892 (31.1%) | 329 (11.5%) | |||
| Housing tenure | ||||||||||||
| Mortgaged/owned | 1724 (29.3%) | 4161 (70.7%) X2 = 140.8 p < 0.001 | 4253 (72.3%) | 680 (11.6%) | 484 (8.2%) | 468 (8.0%) | X2 = 97.8 p < 0.001 | 2748 (58.2%) | 1447 (30.6%) | 527 (11.2%) | X2 = 13.8 p = 0.008 | |
| Privately rented | 243 (43.5%) | 316 (56.5%) | 358 (64.0%) | 76 (13.6%) | 59 (10.6%) | 66 (11.8%) | 266 (64.4%) | 101 (24.5%) | 46 (11.1%) | |||
| Subsidised rented | 306 (49.6%) | 311 (50.4%) | 354 (57.4%) | 96 (15.6%) | 57 (9.2%) | 110 (17.8%) | 248 (60.6%) | 103 (25.2%) | 58 (14.2%) | |||
| Home overcrowding | ||||||||||||
| Up to 1 person/room | 2072 (30.8%) | 4652 (69.2%) | X2 = 34.9 p < 0.001 | 4758 (70.8%) | 812 (12.1%) | 565 (8.4%) | 589 (8.8%) | X2 = 21.7 p < 0.001 | 3099 (58.5%) | 1601 (30.2%) | 597 (11.3%) | X2 = 11.2 p = 0.004 |
| >1 person/room | 126 (48.1%) | 136 (51.9%) | 163 (62.2%) | 27 (10.3%) | 29 (11.1%) | 43 (16.4%) | 120 (64.9%) | 36 (19.5%) | 29 (15.7%) | |||
| Maternal daily alcohol | ||||||||||||
| No | 1309 (24.8%) | 3964 (75.2%) | X2 = 6.96 p =0.008 | 3732 (70.8%) | 629 (11.9%) | 450 (8.5%) | 462 (8.8%) | X2 = 1.47 p = 0.688 | 2520 (60.6%) | 1177 (28.3%) | 461 (11.1%) | X2 = 17.0 p < 0.001 |
| Yes | 219 (21.0%) | 824 (79.0%) | 753 (72.2%) | 123 (11.8%) | 78 (7.5%) | 89 (8.5%) | 452 (53.0%) | 1466 (33.9%) | 573 (13.1%) | |||
Figures for CP trajectory class and alcohol frequency pattern are derived using modal-class assignment and hence these data only approximate the associations estimated in the final one-step model. Samples sizes vary depending on the availability of data on each potential confounder.