Table 2.

Adjusted odds ratios with 95% CI for spirometry clusters (Cluster-normal as a reference).

Risk factors	Cluster	Actual data Adjusted OR (95% CI)	p-value	Imputed data Adjusted OR (95% CI)	p-value
Male	Obstructive	0.90 (0.70, 1.15)	0.404	0.90 (0.77, 1.05)	0.176
	Restrictive	1.13 (0.87, 1.45)	0.354	1.21 (1.04, 1.41)	0.013
Maternal age	Obstructive	1.01 (0.98, 1.04)	0.265	1.01 (0.99, 1.02)	0.519
	Restrictive	1.01 (0.98, 1.04)	0.468	1.00 (0.98, 1.01)	0.741
Gestational age	Obstructive	0.96 (0.89, 1.03)	0.265	0.95 (0.91, 0.99)	0.012
	Restrictive	0.96 (0.88, 1.03)	0.267	0.98 (0.94, 1.02)	0.371
Birth weight centiles	Obstructive	0.97 (0.93, 1.01)	0.198	0.97 (0.95, 0.99)	0.032
	Restrictive	1.00 (0.99, 1.00)	0.997	0.99 (0.97, 1.020)	0.849
Parental asthma	Obstructive	1.17 (0.87, 1.55)	0.287	1.11 (0.93, 1.33)	0.248
	Restrictive	1.15 (0.84, 1.56)	0.390	0.87 (0.71, 1.06)	0.160
Maternal smoking during pregnancy	Obstructive	1.51 (1.11, 2.06)	0.009	1.37 (1.14, 1.65)	<0.001
	Restrictive	0.91 (0.62, 1.32)	0.604	0.89 (0.72, 1.11)	0.314
Breast feeding first six months	Obstructive	0.98 (0.71, 1.34)	0.877	1.18 (0.96, 1.44)	0.101
	Restrictive	0.91 (0.64, 1.27)	0.572	1.01 (0.82, 1.24)	0.913
Pet ownership first year of lifea	Obstructive	1.11 (0.86, 1.41)	0.418	1.02 (0.87, 1.19)	0.778
	Restrictive	1.35 (1.03, 1.75)	0.026	1.29 (1.09, 1.51)	0.002
Early childhood wheezeb	Obstructive	1.79 (1.39, 2.29)	<0.001	1.86 (1.60, 2.17)	<0.001
	Restrictive	1.32 (1.01, 1.71)	0.038	1.31 (1.12, 1.54)	<0.001
BMI z-score at first LFc	Obstructive	0.92 (0.74, 1.14)	0.461	1.00 (0.87, 1.14)	0.955
	Restrictive	0.83 (0.66, 1.03)	0.098	0.68 (0.59, 0.78)	<0.001
Current wheeze at first LF	Obstructive	1.88 (1.23, 2.87)	0.003	1.34 (1.05, 1.71)	0.016
	Restrictive	1.10 (0.64, 1.90)	0.719	1.06 (0.79, 1.41)	0.697
Current asthma diagnosis at first LF	Obstructive	1.07 (0.70, 1.63)	0.760	1.47 (1.15, 1.86)	0.002
	Restrictive	0.62 (0.36, 1.06)	0.078	0.83 (0.62, 1.11)	0.204
Current sensitization at first LF	Obstructive	1.45 (1.08, 1.93)	0.012	1.25 (1.04, 1.51)	0.017
	Restrictive	1.10 (0.78, 1.53)	0.576	1.01 (0.82, 1.24)	0.906
Current Parental smoking at first LF	Obstructive	1.21 (0.93, 1.57)	0.146	1.16 (0.98, 1.36)	0.075
	Restrictive	0.92 (0.69, 1.23)	0.577	0.85 (0.71, 1.02)	0.081

LF: lung function.

Where adjustment is done for all the factors, i.e., all factors included in the model.

Variance inflation factor (VIF): VIF for both models were less than 5. VIF for each risk factors are given in Supplementary Table S12. p-values < 0.05 are shown in bold.

^aPet inside the house or contact with pets most of the time in first year of life.

^bCurrent wheeze at age five or below years.

^cBased on the British 1990 Growth Reference.