Breastfeeding and childhood asthma: a six-year population-based cohort study

BMC Pediatrics

Table 1 Comparison of the 6-year cohort and the baseline study population, Espoo, Finland 1991–1997.

	Baseline		Lost to follow-up		6-year-cohort
Characteristics at baseline	N	%	N	%	N	%
Number	2568	100	584	22.7	1984	77.3
Age (years)
1	424	16.5	100	17.1	324	16.3
2	405	15.8	104	17.8	301	15.2
3	310	16.0	92	15.8	318	16.0
4	400	15.6	67	11.5	333	16.8
5	415	16.2	101	17.3	314	15.8
6	391	15.2	81	13.9	310	15.6
7-	123	4.8	39	6.7	84	4.2
Gender
Boy	1310	51.0	309	52.9	1001	50.5
Girl	1258	49.0	275	47.1	983	49.5
Any allergic disease
Yes	337	13.1	81	13.9	256	12.9
No	2231	86.9	503	86.1	1728	87.1
Single parent/guardian
Yes	183	7.1	53	9.1	130	6.6
No	2385	92.9	531	90.9	1854	93.4
Highest level of parental education
Non-professional	498	19.5	129	22.3	369	18.7
Trade school	663	25.9	140	24.2	523	26.5
College or university	1395	54.6	310	53.5	1085	54.9
Missing information	12
Exposure to ETS
Yes	267	10.4	76	13.1	191	9.7
No	2291	89.6	504	86.9	1787	90.3
Missing Information	10
Gas stove
Yes	86	3.4	24	4.1	62	3.1
No	2469	96.6	556	95.9	1913	96.9
Missing Information	13
Hairy/Feathery Pets
Yes	480	18.7	113	19.3	367	18.5
No	2088	81.3	471	80.7	1617	81.5
Type of day care
100% Home	940	36.6	210	36.0	730	36.8
100% Family	513	20.0	119	20.4	394	19.9
100% Centre	252	9.8	56	9.6	196	9.9
Combinations	863	33.6	199	34.1	664	33.5

ISSN: 1471-2431