Table 1. Demographic characteristics of study subjects:

Basic characteristics	Cases (n=186)(%)	Controls (n=210)(%)	p value
Age (yrs):
Mean ± SD	37.70 ± 0.81	35.98 ± 0.77	0.124
Sex:
Female	56 (30.1)	53 (25.2)	0.279
Male	130 (69.9)	157(74.8)
Location:
Urban	60 (32.3)	83 (39.5)	0.133
Rural	126 (67.7)	127(60.5)