Table 2.

Relationship between different variables and blood lead concentrations of study subjects

Variable	Mean ± SD	Median [IQR]	Test result
Gender
Boy	2.40 ± 2.85	1.90 [1.10–3.20]	z = 0.86 p = 0.39
Girl	2.58 ± 2.40	1.70 [1.10–2.80]
Age
≥ 72 month	3.03 ± 2.28	2.40 [1.10–4.60]	χ2 = 5.58 p = 0.13
12–24 month	2.86 ± 4.15	1.85 [1.10–2.60]
24–48 month	2.08 ± 1.34	1.70 [1.10–2.50]
48–72 month	2.28 ± 2.19	1.70 [1.10–2.80]
Exposure to paint
Yes	2.92 ± 3.32	2.10 [1.20–3.30]	z = 1.39 p = 0.16
No	2.39 ± 2.46	1.80 [1.10–2.75]
Exposure to soil
Yes	2.49 ± 1.61	2.20 [1.10–3.25]	z = 1.02 p = 0.31
No	2.48 ± 2.75	1.80 [1.10–2.70]
Occupation of father
Employee	2.18 ± 1.33	1.90 [1.10–2.80]	χ2 = 3.25 p = 0.66
Martial	2.82 ± 2.10	2.10 [1.10–4.15]
Laborer	3.20 ± 3.96	1.80 [1.20–3.30]
Repairman	2.30 ± 1.20	2.25 [1.35–2.97]
Driver	1.79 ± 0.87	1.70 [1.00–2.30]
Self-employment	2.42 ± 2.85	1.10 [1.70–1.70]
Education levels of parents
Primary school	3.04 ± 3.89	1.60 [1.10–3.20]	χ2 = 0.87 p = 0.83
Middle School	2.46 ± 1.64	2.05 [1.12–3.30]
Diploma	2.51 ± 2.96	1.80 [1.10–2.75]
Bachelor	2.16 ± 1.43	1.80 [1.10–2.80]
Occupation of mother
Housewife	2.45 ± 2.64	1.80 [1.10–2.80]	χ2 = 1.79 p = 0.41
Employment	2.47 ± 1.61	1.90 [1.12–3.42]
Self-employment	3.29 ± 4.26	2.05 [1.40–3.32]
Opium use in parents
Yes	2.43 ± 1.53	2.10 [1.17–3.12]	z = 0.64 p = 0.52
No	2.48 ± 2.66	1.80 [1.10–2.80]
Cigarette smoking
Yes	2.49 ± 2.70	1.90 [1.20–3.17]	z = 0.58 p = 0.56
No	2.32 ± 1.41	1.80 [1.10–2.80]