Demographic and socio-economic conditions.

aOnly Mahottari and Vaishali did not differ significantly.bRajshahi differs significantly from other sites.cEach site differs from other significantly.dMahottari differs from all sites and Rajshahi differs from Mahottari and Muzzafarpur.eNo significant difference between Rajshahi and Mahottari as well as between Vaishali and Muzzafarpur, but Rajshahi and Mahottari differed significantly from Vaishali and Muzzafarpur.fVaishali and Muzzafarpur do not differ significantly.gEach site differs significantly from other.hTwo sites of India did not differ significantly in-between them.