the education level of the largest group of casea and controls were primary school(63.57% of and 65.71% of controls),.Vocational school(1.43%of cases,4.29% of controls) and graduate from university or higher (2.14% of cases 0.71% of controls) were the smallest group.Distribution of education showed no significant difference (p>0.05).
socio-demographic charcterstics