Table 1 Study population characteristics in children with recurrent respiratory tract infections (RRIs) and the comparison group.

Mothers’ age, years, mean (SD)

31 (4.2)

30 (4.6)

0.15

Maternal education (%)^a

Low (up to 12 years)

25.5

36.0

0.02

Medium (13–15 years)

44.0

30.0

High (over 15 years)

30.5

34.0

Maternal smoking (%)^b (yes/no)

10.0

13.0

0.34

Child sex male (%)

58

52

0.21

Gestational weeks, mean (SD)

39.7 (1.5)

39.8 (1.4)

0.28

Apgar score at 1 min, mean (SD)

8.6 (1.4)

8.6 (1.3)

0.99

Tympanostomy tube insertions (%)^c

42

1

 < 0.001

Antibiotic treatments before 1 year of age (%)

 < 0.001

0

34

77

1–4

45

22

5–10

21

1

 > 10

0

0

Antibiotic treatments before 2 years of age (%)^d

 < 0.001

0

0

25

1–4

31

63

5–10

67

12

 > 10

2

0

Respiratory tract infections before 1 year of age (%)

 < 0.001

0

27

68

1–4

42

28

5–10

30

4

 > 10

1

0

Respiratory tract infections before 2 years of age (%)^e

 < 0.001

0

0

38

1–4

21

42

5–10

60

18

 > 10

19

2

Prenatal maternal psychological distress questionnaires, total scores at gwks 34^f, mean (IQR)

EPDS

5.32 (2–8.4)

4.5 (3–6.7)

0.009

PRAQ

24.0 (18–28)

22.5 (17–27)

0.028

SCL-90

3.7 (0–5)

3.3 (0–4)

0.085