Table 2.

Demographic and clinical characteristics of the pediatric patients (N = 143).

Characteristics	N = 143
Age (years), median (IQR)	2.7 (1.2–6.3)
Male sex, n (%)	83 (55.6%)
Existing chronic medical conditions#, n (%)	130 (90.9%)
Existing chronic respiratory tract diseases∧, n (%)	50 (35.0%)
Current or previous allergic rhinitis, n (%)	36 (25.2%)
Current or previous asthma, n (%)	15 (10.5%)
Current or previous eczema, n (%)	26 (18.2%)
Current or previous chronic lung disease, n (%)	5 (3.5%)
Parental perception on child's health status (Scale of 1–5)@, mean ± SD	3.5 ± 0.9
Need of long-term medication, n (%)	20 (14.0%)
Premature at birth (<37 weeks' gestation), n (%)	24 (16.8%)
Presence of other household smoker(s), n (%)	20 (14.0%)
Urine cotinine concentration (μg/L)*, median (IQR)	0.34 (0.0–1.18)

^# Including chronic respiratory tract diseases, heart disease, developmental problems, allergic rhinitis, eczema, asthma.

^∧ Including allergic rhinitis, asthma, chronic lung diseases.

^@ A Likert scale of 1 to 5; 1-very poor health condition, 5-very good health condition.

^*Valid baseline urine samples were available for 89 children.