Frequency of exposures in case and control participants, adjusted ORs from complete case and multiple imputation analyses and population attributable fraction (PAF) percentage
| Exposures | Cases n=610 | Controls n=2658 | Adjusted OR (95% CI) | PAF (%) | Confounders adjusted for§* |
|---|---|---|---|---|---|
| Safety gates anywhere in house† | [12] | [124] | n=1921 | – | HADS, PDH, first child, stair safety, hours out-of-home child care |
| Used | 465 (76.3) | 2013 (79.4) | 1 [reference] 1.22 (0.92 to 1.62) | ||
| Did not use | 142 (23.8) | 521 (20.6) | |||
| Exposures only for households with stairs | Cases | Controls | |||
| n=598 | n=2476 | ||||
| [6] | [7] | ||||
| Stair gate† | [13] | [40] | n=2401 | 24 21 | Child's ability to open safety gate, taught child rules about going down the stairs, carrying things down the stairs, leaving things on stairs, stair safety |
| Gate closed | 174 (29.7) | 1245 (51.1) | 1 [reference] | ||
| Gate left open | 210 (35.9) | 555 (22.8) | 3.09 (2.39 to 4.00) | ||
| No gate | 201 (34.4) | 636 (26.1) | 2.50 (1.90 to 3.29) | ||
| Carpeted stairs† | [8] | [28] | n=2394 | 5 | HADS, PDH, stair safety |
| Had | 507 (85.9) | 2248 (91.8) | 1 [reference] | ||
| Did not have | 83 (14.1) | 200 (8.2) | 1.52 (1.09 to 2.10) | ||
| Landing part-way up the stairs† | [5] | [28] | n=2766 | 18 | Stair safety |
| Had | 180 (30.4) | 892 (36.4) | 1 [reference] | ||
| Did not have | 413 (69.6) | 1556 (63.6) | 1.34 (1.08 to 1.65) | ||
| Spiral or winding stairs† | [7] | [30] | n=2757 | – | Stair safety |
| Did not have | 495 (83.8) | 2044 (83.6) | 1 [reference] | ||
| Had | 96 (16.2) | 402 (16.4) | 0.97 (0.75 to 1.27) | ||
| Tripping hazards on stairs‡ | [18] | [51] | n=2367 | – | HADS, PDH, stair safety |
| Did not have | 397 (68.4) | 1493 (61.6) | 1 [reference] | ||
| Had | 183 (31.5) | 932 (38.4) | 0.77 (0.62 to 0.97) | ||
| Stairs too steep$† | [18] | [80] | n=2744 | – | Stair safety |
| Other responses | 362 (62.4) | 1653 (69.0) | 1 [reference] | ||
| Agree | 218 (37.6) | 743 (31.0) | 1.21 (0.94 to 1.56) | ||
| Stairs too narrow$† | [23] | [98] | n=2742 | – | Stair safety |
| Other responses | 421 (73.2) | 1894 (79.7) | 1 [reference] | ||
| Agree | 154 (26.8) | 484 (20.4) | 1.28 (0.96 to 1.70) | ||
| Stairs poorly lit$† | [26] | [94] | n=2380 | – | HADS, PDH, stair safety |
| Other responses | 469 (82.0) | 2053 (86.2) | 1 [reference] | ||
| Agree | 103 (18.0) | 329 (13.8) | 1.32 (0.97 to 1.79) | ||
| Steps in need of repair$† | [25] | [96] | n=2378 | 5 | HADS, PDH, stair safety |
| Other responses | 506 (88.3) | 2233 (93.8) | 1 [reference] | ||
| Agree | 67 (11.7) | 147 (6.2) | 1.71(1.16 to 2.50) | ||
| Banister/handrail on stairs in need of repair$† | [32] | [98] | n=2377 | – | HADS, PDH, stair safety |
| Other responses | 498 (88.0) | 2175 (91.5) | 1 [reference] | ||
| Agree | 68 (12.0) | 203 (8.5) | 1.32 (0.92 to 1.88) | ||
| Stair covering in need of repair$† | [26] | [96] | n=2378 | HADS, PDH, stair safety | |
| Other responses | 501 (87.6) | 2205 (92.6) | 1 [reference] | ||
| Agree | 71 (12.4) | 175 (7.4) | 1.41 (0.99 to 2.03) | ||
| Stairs safe to use$† | [10] | [25] | n=2391 | 5 | HADS, PDH, stair safety |
| Other responses | 487 (82.8) | 2180 (88.9) | 1 [reference] | ||
| Disagree | 101 (17.2) | 271 (11.1) | 1.46 (1.07 to 1.99) | ||
| Handrails on all stairs$† | [1] | [20] | n=2416 | – | HADS, PDH, stair safety |
| Had | 382 (64.0) | 1393 (56.7) | 1 [reference] | ||
| Did not have | 215 (36.0) | 1063 (43.3) | 0.69 (0.56 to 0.86) | ||
| Banisters or railings on all stairs$† | [22] | [60] | n=2301 | – | HADS, PDH, stair safety |
| Had | 424 (73.6) | 1930 (79.9) | 1 [reference] | ||
| Did not have | 152 (26.4) | 486 (20.1) | 1.27 (0.99 to 1.63) | ||
| Rules about going down the stairs | [20] | [70] | n=1840 | – | HADS, PDH, first child, child's ability to open safety gate, stair gate, stair safety |
| Had taught child | 405 (70.1) | 1782 (74.1) | 1 [reference] | ||
| Had not taught child | 173 (29.9) | 624 (25.9) | 1.36 (0.92 to 2.02) | ||
| Rules about carrying things while going down the stairs | [20] | [68] | n=1840 | – | HADS, PDH, first child, child's ability to open safety gate, stair gate, stair safety |
| Had taught child | 287 (49.7) | 1274 (52.9) | 1 [reference] | ||
| Had not taught child | 291 (50.4) | 1134 (47.1) | 1.21 (0.83 to 1.75) | ||
| Rules about leaving things on stairs | [22] | [64] | n=1838 | – | HADS, PDH, first child, child's ability to open safety gate, stair gate, stair safety |
| Had taught child | 256 (44.4) | 1073 (44.5) | 1 [reference] | ||
| Had not taught child | 320 (55.6) | 1339 (55.5) | 0.85 (0.60 to 1.22) | ||
| Exposure only for households with stairs and banisters | Cases (n=424) | Controls (n=1930) | |||
| Banister width (inches) | [190] | [803] | n=627 | – | Stair safety |
| 0–2.5 | 94 (40.2) | 400 (35.5) | 1 [reference] | ||
| 2.5–3.75 | 67 (28.6) | 363 (32.2) | 0.83 (0.53 to 1.29) | ||
| ≥3.75 | 73 (31.2) | 364 (32.3) | 0.75 (0.48 to 1.18) | ||
| Exposures only for children aged 0–36 months | Cases (n= 475) | Controls (n=2009) | |||
| Baby walker | [14] | [32] | n=1620 | – | HADS, PDH, first child, hours out-of-home child care |
| Did not use | 326 (70.7) | 1302 (65.9) | 1 [reference] | ||
| Used | 135 (29.3) | 675 (34.1) | 0.83 (0.63 to 1.10) | ||
| Playpen or travel cot | [14] | [30] | n=1615 | – | HADS, PDH, used baby walker, first child, hours out-of-home child care |
| Used | 77 (16.7) | 334 (16.9) | 1 [reference] | ||
| Did not use | 384 (83.3) | 1645 (83.1) | 1.07 (0.75 to 1.53) | ||
| Stationary activity centre | [16] | [33] | n=1611 | – | HADS, PDH, used baby walker, first child, hours out-of-home child care |
| Used | 111 (24.2) | 490 (24.8) | 1 [reference] | ||
| Did not use | 348 (75.8) | 1486 (75.2) | 1.08 (0.80 to 1.46) | ||
[ ] missing values.
Stair safety is a composite variable combining responses to questions marked with $ and grouped as all ‘safe’ responses, some ‘safe’ responses and no ‘safe’ responses. Where the exposure variable is a measure of stair safety, this variable is excluded from the composite stair safety measure used as a confounder in adjusted analyses.
*Conditional logistic regression excludes observations where all cases and their matched controls have the same exposure.
†In the past 24 h.
‡In the past week.
§All models were adjusted for the Index of Multiple Deprivation and distance from the hospital plus listed confounders.
HADS, Hospital Anxiety and Depression Scale; PAF, population attributable fraction; PDH, Parenting Daily Hassles Scale.