Table 3. Association of demographic factors with risk of B-ALL.

Parameters	Patients (%)	Control (%)	Odd ratio	Chi-square	P value
Age (mean)	7.30	11.70
A positive family history	16.77	1.29	15.42	14.59	0.000*
A negative family history	83.22	98.70
Smoking by parent	38.06	41.94	0.85	0.31	0.580
No smoking parent	61.93	58.06
Parental cousin marriage	33.55	21.29	1.87	3.78	0.050*
No cousin marriage	66.45	78.70
Females	56	72	0.65	3.41	0.070
Males	99	83

Notes.

Significant values are shown in (*).