Table 5.

Crude odds ratios(95% CI) for respiratory health outcomes associated with parental smoking by using two-level regression model.

	No. of subjects	Dry night cough	Croup	Pneumonia	Frequent common cold
During pregnancy
Neither	22267	1	1	1	1
Mother only	148	1.22(0.82–1.84)	1.10(0.58–2.10)	0.97(0.69–1.38)	1.01(0.58–1.76)
Father only	16230	1.06(1.00–1.12)*	1.16(1.07–1.26)*	1.08(1.03–1.12)*	1.01(0.94–1.08)
Both	58	1.44(0.79–2.63)	1.25(0.45–3.48)	0.93(0.53–1.64)	0.44(0.14–1.42)
During infancy
Neither	21477	1	1	1	1
Mother only	193	1.12(0.78–1.63)	1.32(0.77–2.24)	0.86(0.63–1.17)	0.85(0.50–1.44)
Father only	17524	1.03(0.97–1.08)	1.14(1.05–1.24)*	1.05(1.01–1.10)*	0.98(0.91–1.05)
Both	90	1.68(1.05–2.69)*	1.67(0.80–3.46)	0.95(0.60–1.50)	0.79(0.38–1.64)
During childhood
Neither	22357	1	1	1	1
Mother only	288	1.39(1.05–1.84)	1.21(0.77–1.92)	0.88(0.68–1.14)	0.82(0.53–1.27)
Father only	18340	1.02(0.96–1.07)	1.14(1.05–1.24)*	1.05(1.01–1.10)*	0.93(0.87–1.00)
Both	245	1.25(0.92–1.71)	1.21(0.73–1.98)	0.97(0.74–1.28)	0.86(0.55–1.36)

*P-value < 0.05.