Table 2 Description of the study population: childrenʼs characteristics.

	Children of women who smoked (n = 71)		Children of women who did not smoke (n = 71)
Note: t = t-value, df = degrees of freedom, p = two-tailed significance test
	mean	SD	mean	SD	t	df	p
Age (in months)	57.2	14.4	57.2	13.7	− 0.012	140	0.990
Birth weight (in grams)	3 240.0	526.0	3 365.0	551.7	1.372	140	0.172
	N	%	N	%	χ2	df	p
Chronic respiratory disease	6	8.5	2	2.8	2.119	1	0.145