Table 1 Comparison of basic data collected in CLARITY cases and controls
From: CLARITY – ChiLdhood Arthritis Risk factor Identification sTudY
All cases | Victorian-born cases | Victorian-born (all) controls | ||||
|---|---|---|---|---|---|---|
n† | n† | n† | ||||
Basic characteristics | ||||||
Child mean age at interview | 262 | 9.5 (SD: 4.5)* | 229 | 9.4 (SD: 4.6)* | 458 | 7.1 (SD 4.2) |
Child female | 262 | 67.2%* | 229 | 68.1%* | 458 | 39.7% |
Child has four Caucasian grandparents | 217 | 87.1%* | 190 | 90.0%* | 378 | 79.1% |
Mother’s age at interview | 256 | 40.3 (SD: 6.0)* | 224 | 40.5 (SD: 5.8)* | 449 | 36.9 (SD: 6.4) |
Father’s age at interview | 243 | 43.0 (SD: 6.6)* | 213 | 43.2 (6.5)* | 398 | 39.4 (SD: 6.8) |
Socio-demographic data | ||||||
Mother’s SEIFA§ score | 90 | 1026.7 (SD: 62.9)* | 74 | 1030.9 (SD: 62.6)* | 305 | 1003.7 (SD: 70.4) |
Father’s SEIFA§ score | 81 | 1026.1 (SD: 64.3)* | 67 | 1033.6 (SD: 61.7)* | 245 | 1006.5 (SD: 71.7) |
Mother’s education | ||||||
Completed year 12 | 257 | 66.2% | 224 | 68.8% | 449 | 71.9% |
Completed postgraduate degree | 202 | 10.4% | 173 | 10.4% | 344 | 10.8% |
Father’s education | ||||||
Completed year 12 | 244 | 57.4% | 215 | 57.7% | 399 | 61.4% |
Completed postgraduate degree | 180 | 12.8% | 157 | 12.7% | 275 | 9.8% |
Mother’s marital status at interview | 256 | 223 | 450 | |||
married | 79.3%* | 80.7%* | 70.9% | |||
divorced | 7.0% | 7.2% | 6.2% | |||
separated | 5.1% | 4.9% | 6.2% | |||
widowed | 0.8% | 0.5% | 1.3% | |||
de facto | 2.0% | 1.8% | 4.9% | |||
never married | 5.9% | 4.9% | 10.2% | |||
Father’s marital status at interview | 246 | 216 | 401 | |||
married | 84.2%* | 84.3%* | 75.8% | |||
divorced | 5.7% | 5.6% | 4.2% | |||
separated | 3.7% | 3.7% | 5.7% | |||
widowed | 0.8% | 0.9% | 0% | |||
de facto | 1.2% | 1.4% | 3.7% | |||
never married | 4.1% | 3.7% | 9.2% | |||
don’t know | 0.4% | 0.5% | 1.3% | |||
Mother hours in paid work (mean) | 220 | 23.0 (SD: 20.0) | 193 | 22.9 (SD: 19.9) | 340 | 20.2 (SD: 19.1) |
Father hours in paid work (mean) | 216 | 43.0 (SD: 15.1) | 190 | 43.3 (SD: 15.1) | 312 | 41.5 (SD: 16.5) |
Mother cigarettes/day | 255 | 222 | 451 | |||
none | 80.0%* | 79.7%* | 72.7% | |||
1-10/day | 9.8% | 9.9% | 14.9% | |||
11-20/day | 8.2% | 8.6% | 10.2% | |||
21-40/day | 2.0% | 1.8% | 2.0% | |||
41+/day | 0% | 0% | 0.2% | |||
Father cigarettes/day | 242 | 213 | 397 | |||
none | 78.1% | 79.3%* | 71.5% | |||
1-10/day | 7.9% | 8.0% | 10.8% | |||
11-20/day | 10.3% | 9.4% | 10.8% | |||
21-40/day | 2.9% | 2.8% | 6.3% | |||
41+/day | 0.8% | 0.5% | 0.5% | |||
Mother alcoholic drinks/wk mean (SD) | 249 | 2.2 (SD: 3.8) | 216 | 2.4 (SD: 4.0) | 435 | 1.9 (SD: 3.0) |
Father alcoholic drinks/wk mean (SD) | 232 | 4.9 (SD: 6.6) | 204 | 4.8 (SD: 6.6) | 384 | 5.1 (SD: 7.9) |
Pregnancy & Birth | ||||||
Mother’s age at child’s birth (mean, yrs) | 256 | 30.2 (SD: 4.9)* | 224 | 30.6 (SD: 4.8)* | 449 | 29.3 (SD: 5.3) |
Father’s age at child’s birth (mean, yrs) | 243 | 33.0 (SD: 5.7)* | 213 | 33.4 (SD: 5.7)* | 398 | 32.0 (SD: 6.1) |
Planned pregnancy | 262 | 79.8% | 229 | 81.2% | 456 | 77.6% |
planned natural | 73.7 | 75.6% | 72.8% | |||
planned assisted | 6.1% | 5.7% | 4.8% | |||
unplanned | 20.2% | 18.8% | 22.4% | |||
Child adopted | 262 | 0% | 229 | 0% | 455 | 0.7% |
Mother smoked during this pregnancy | 256 | 223 | 448 | |||
Nil | 84.0%* | 83.9%* | 74.6% | |||
Less than daily | 5.9% | 6.3% | 10.0% | |||
1-10/day | 6.3% | 6.7% | 9.4% | |||
11-20/day | 3.5% | 3.2% | 4.7% | |||
21-40/day | 0.4% | 0% | 1.3% | |||
41+/day | 0% | 0% | ||||
Father smoked during this pregnancy | 235 | 207 | 385 | |||
Nil | 77.0%* | 78.3%* | 68.8% | |||
Less than daily | 3.0% | 2.9% | 4.9% | |||
1-10/day | 5.1% | 5.3% | 9.6% | |||
11-20/day | 11.1% | 10.1% | 11.4% | |||
21-40/day | 3.4% | 3.4% | 4.9% | |||
41+/day | 0.4% | 0% | 0.3% | |||
Mother major illness during pregnancy | 261 | 26.1% | 228 | 25.0% | 452 | 23.0% |
Mother meds/supps during pregnancy | ||||||
multivitamins | 245 | 24.9% | 215 | 25.1% | 409 | 30.8% |
folate | 246 | 61.4% | 216 | 60.7% | 409 | 64.8% |
calcium | 246 | 10.2% | 216 | 9.7% | 409 | 14.9% |
iron | 246 | 35.4% | 216 | 35.6% | 409 | 40.3% |
vitamin D | 246 | 3.3%* | 216 | 3.7% | 409 | 7.8% |
fish oil | 246 | 2.9% | 216 | 2.8% | 409 | 6.4% |
antibiotics | 246 | 3.7% | 216 | 3.7% | 409 | 3.7% |
other | 244 | 11.5%* | 214 | 11.2% | 409 | 6.4% |
Mother any alcohol during pregnancy | 255 | 18.1% | 222 | 19.4%* | 448 | 18.3% |
Mother any coffee during pregnancy | 253 | 56.1%* | 220 | 57.7%* | 448 | 54.7% |
Child’s gestation (mean, weeks) | 211 | 39.3 (SD: 1.8) | 186 | 39.3 (SD: 1.8) | 389 | 39.0 (SD: 2.3) |
Child mode of delivery | 90 | 71 | 210 | |||
normal vaginal | 63.3% | 63.4% | 60.0% | |||
assisted vaginal | 12.2% | 12.7% | 11.9% | |||
caesarian | 23.3% | 22.5% | 27.1% | |||
other | 1.1% | 1.4% | 1.0% | |||
Child birthweight (mean, g) | 225 | 3354.0 (SD: 613.8) | 200 | 3357.2 (SD: 581.5) | 344 | 3363.0 (SD: 676.9) |
Child birthlength (mean, cm) | 194 | 50.2 (SD: 3.4) | 174 | 50.1 (SD: 3.4) | 268 | 50.4 (SD: 3.7) |
Child head circumference (mean, cm) | 161 | 34.8 (SD: 3.0) | 149 | 34.8 (SD: 3.1) | 176 | 34.6 (SD: 3.1) |
Child in multiple birth | 253 | 3.6% | 221 | 4.1% | 448 | 3.1% |
Child birth order (all live-born sibs) mean | 262 | 1.90 (SD:1.02) | 229 | 1.93 (SD: 1.05) | 456 | 1.85 (SD: 1.03) |
Early Life | ||||||
Child breastfeeding | ||||||
any | 260 | 85.8% | 228 | 86.4% | 454 | 81.3% |
if any, age started (wks) (mean, SD) | 217 | 0.3 (SD 1.6) | 191 | 0.3 (SD 1.7) | 360 | 0.9 (SD 5.0) |
if any, weeks breastfed (mean, SD) | 214 | 36.5 (SD 29.9) | 188 | 36.5 (SD 30.4) | 357 | 37.6 (SD 34.4) |
Child formula feeding | ||||||
age started (weeks) | 194 | 18.2 (SD 19.9) | 173 | 18.3 (SD 20.1) | 348 | 16.4 (SD 16.5) |
weeks formula fed | 239 | 35.1 (SD 34.3) | 210 | 35.9 (35.2) | 433 | 37.2 (SD 37.1) |
Child cow’s milk commence age (weeks) | 221 | 58.8 (SD 17.6) | 193 | 57.9 (SD 17.6)* | 405 | 61.6 (SD 22.4) |
Child solids commence age (weeks) | 234 | 24.2 (SD 16.1) | 210 | 23.8 (SD 16.4) | 424 | 23.9 (SD 9.6) |
Mother smokes indoors near child | 241 | 211 | 216 | |||
usually | 0.8% | 1.0% | 1.4% | |||
sometimes | 3.7% | 3.8% | 6.9% | |||
never | 95.4% | 95.3% | 91.7% | |||
Father smokes indoors near child | 231 | 203 | 192 | |||
usually | 1.3% | 1.0% | 2.6% | |||
sometimes | 3.5% | 3.5% | 5.7% | |||
never | 95.2% | 95.6% | 91.7% | |||