Background
Objectives
Methods
Study population
Assessment of main exposure
Initial variable | % | New categories (*without unknowns) | % |
---|---|---|---|
Gender n = 30,769 | |||
Boy | 51.3 | – | – |
Girl | 48.7 | ||
Child’s age n = 30,707 | – | ||
≤27 mo | 7.3 | ||
28–32 mo | 88.9 | ||
≥33 mo | 3.8 | ||
Birthweight n = 30,757 | n = 30,757 | ||
< 1000 g | 0.1 | ||
1000–1499 g | 0.6 | ||
1500–1999 g | 1.2 | ||
2000–2499 g | 5.1 | < 2500 g | 7.0 |
2500–2999 g | 19.6 | ≥2500 g | |
3000–3499 g | 39.9 | 93.0 | |
3500–3999 g | 25.0 | ||
4000–4499 g | 5.5 | ||
≥4500 g | 3.0 | ||
BMI (kg/m2) at examination | percentiles | n = 29,120 | |
n = 29,120 | |||
< 13.1 | 1.0 | ||
< 13.9 | 5.0 | ||
< 14.4 | 10.0 | ||
< 15.2 | 25.0 | p3-p97 | 91.8 |
< 16.0 | 50.0 | >p97 | 6.3 |
< 17.0 | 75.0 | <p3 | 1.9 |
< 18.0 | 90.0 | ||
< 18.7 | 95.0 | ||
< 20.9 | 99.0 | ||
Mother’s age in years at childbirth n = 29,883 | n = 29,883 | ||
9–15 | 0.2 | ||
16–17 | 0.7 | < 18 | 0.9 |
18–24 | 18.3 | 18/30 | 59.0 |
25–30 | 40.8 | 31/37 | 33.0 |
31–37 | 32.9 | ≥38 | 7.1 |
38–44 | 6.9 | ||
45–53 | 0.2 | ||
Mother’s level of education n = 30,769 | n = 24,530 | ||
Did not complete primary school/no schooling | 2.3 | 22.4 | |
Completed primary school/did not complete lower secondary | 4.3 | < Upper secondary school | 30.8 |
Completed lower secondary school | 11.2 | Completed upper secondary school | 46.8 |
Completed upper secondary school | 24.6 | Completed third-level/university or not | |
Completed third-level/university or not | 37.3 | ||
Unknown | 20.3 | ||
Mother’s occupation n = 15,038 (2006–9) | n = 7293 | ||
Unemployed/stay-at-home | 18.5 | Unemployed/stay-at-home | |
Part time | 9.9 | ||
Early retirement/invalidity/work incapacity | 1.0 | Early retirement/work incapacity/invalidity | 38.1 |
On full-time career break/parental leave or similar | 1.2 | Student | 2.1 |
Student | 0.1 | Works full time or part time/career break/parental leave | 0.3 |
Works full time | 17.7 | 59.5 | |
Unknown | 51.6 | ||
Family income n = 15,038 (2006–9) | n = 7285 | ||
No stable income | 0.6 | ||
1 or 2 incomes from benefits | 5.5 | No stable income | 1.2 |
1 income from employment | 16.3 | 1or 2 incomes from benefits | 11.4 |
1 income from employment + 1 | 0.1 | 1 income from employment | 33.6 |
income from benefits | 0.3 | 2 incomes, of which ≥1 income from employment | 53.8 |
Other (specify) | 26.0 | ||
2 incomes from employment | 51.2 | ||
Unknown | |||
Mother’s standard of French n = 16,990 (2006–9) | |||
None | 1.8 | ||
A little | 8.1 | ||
Very good | 86.9 | ||
Unknown | 3.2 | First language n = 28,582 (2006–12) | |
Language spoken at home n = 13,783 (2010–12) | |||
Language other than French | 34.3 | French | 77.6 |
French | 53.8 | Other | 22.4 |
Unknown | 11.9 | ||
Goes to a nursery n = 13,783 (2010–12) | n = 12,040 | ||
Yes | 48.8 | ||
No | 38.5 | Yes | 55.9 |
Unknown | 12.7 | No | 44.1 |
Family environment n = 30,769 | n = 28,871 | ||
Parents separated | 7.5 | ||
Only sees one parent | 1.3 | ||
Stepfamily | 0.4 | Parents separated/only sees one parent/stepfamily | 9.8 |
Children’s home/home/foster home | 0.6 | Parents together | 90.2 |
Grandparents, uncles/aunts, others | 0.6 | ||
Parents together | 84.6 | ||
Unknown | 5.0 |
Assessment of other covariates
Outcome ascertainment
Statistical analysis
Results
Variables of behaviour | Total | Parents together | Parentsseparated | P |
---|---|---|---|---|
≥ 1 person smokes in the home daily −2006-09 (n = 13,667) | (n = 2962) | (n = 2473) | (n = 489) | |
% yes | 22.2 | 20.7 | 36.1 | |
Crude OR (95% CI) | 1 | 2.2 (1.9–2.4) | < 0.001 | |
Daily tooth brushing −2006-12 (n = 25,976) | (n = 2046) | (n = 1851) | (n = 195) | 0.007 |
% No | 7.9 | 7.7 | 9.3 | |
Crude OR (95% CI) | 1 | 1.2 (1.1–1.4) | ||
Sees the dentist −2010-12 (n = 10,686) | (n = 7826) | (n = 7054) | (n = 772) | 0.002 |
% No | 81.2 | 80.8 | 84.8 | |
Crude OR (95% CI) | 1 | 1.3 (1.1–1.6) | ||
Vision screening −2010-12 (n = 12,725) | (n = 4923) | (n= | (n = 527) | < 0.001 |
% No | 41.4 | 4396) | 48.2 | |
Crude OR (95% CI) | 40.7 | 1.4 (1.2–1.5) |
≥ 1 person smokes at home daily | Child does not brush his or her teeth daily | Child doesnot have a dentist | No vision screening | |
---|---|---|---|---|
(2006–09) | (2006–12) | (2010–12) | (2010–12) | |
Variable | OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) |
Family structure | ||||
Parents together | 1 | 1 | 1 | 1 |
Parents separated | 1.7 (1.5–2.0) | 1.1 (0.9–1.2) | 1.3 (1.1–1.6) | 1.2 (1.1–1.4) |
P | < 0.001 | 0.8 | 0.03 | 0.005 |
Mother’s level of education | ||||
Third-level | 1 | 1 | 1 | 1 |
Completed upper secondary | 2.6 (2.3–2.9) | 2.0 (1.7–2.3) | 1.5 (1.3–1.7) | 1.6 (1.4–1.8) |
< Upper secondary | 4.9 (4.3–5.6) | 4.1 (3.6–4.7) | 1.6 (1.4–1.9) | 2.1 (1.8–2.4) |
P | < 0.001 | < 0.001 | < 0.001 | < 0.001 |
Mother’s age at childbirth | ||||
< 18 years | 1.7 (1.1–2.7) | 0.9 (0.5–1.4) | ||
18/30 years | 1 | 1 | ||
31/37 years | 0.9 (0.8–1.0) | 1.1 (1.0–1.3) | ||
38 years and more | 1.1 (0.9–1.3) | 1.3 (1.1–1.6) | ||
P | 0.03 | 0.02 | ||
Mother speaks French | ||||
Yes | 1 | 1 | 1 | 1 |
No | 0.7 (0.6–0.9) | 1.5 (1.3–1.7) | 1.2 (1.1–1.3) | 1.5 (1.4–1.7) |
P | < 0.001 | < 0.001 | 0.02 | < 0.001 |
≥ 1 parent allergic | ||||
No | 1 | |||
Yes | 1.2 (1.1–1.4) | |||
P | < 0.001 | |||
Nursery attendance | ||||
Yes | 1 | 1 | ||
No | 0.8 (0.7–0.9) | 2.0 (1.8–2.3) | ||
P | 0.006 | < 0.001 | ||
Birthweight | ||||
≥2500 g | 1 | 1 | ||
< 2500 g | 1.4 (1.2–1.8) | 1.3 (1.1–1.7) | ||
P | < 0.001 | 0.02 | ||
Age of the child | ||||
≥33 mo | 1 | 1 | 1 | |
28–32 mo | 0.9 (0.7–1.1) | 1.4 (1.1–1.9) | 1.3 (1.0–1.6) | |
≤ 27 mo | 1.2 (0.9–1.6) | 1.7 (1.2–2.5) | 1.9 (1.4–2.6) | |
P | 0.002 | 0.01 | < 0.001 | |
Grommets | ||||
Yes | 1 | |||
No | 0.7 (0.5–0.9) | |||
P | < 0.001 | |||
The child has eczema | ||||
No | 1 | |||
Yes | 0.9 (0.7–1.0) | |||
P | 0.04 |
Smoking at home* | ||
---|---|---|
Family structure | First | First |
language: FR | language: ≠FR | |
Adjusted OR | Adjusted OR | |
(95% CI) | (95% CI) | |
Parents together | 1 | 1 |
Parents separated | 1.9 (1.6–2.2) | 0.7 (0.4–1.3) |
P | < 0.001 | 0.3 |