Table 1: Comparison of oral health status variables between III- and V-grade children in three schools

		School I median (range)						School II median (range)						School III median (range)
Variables		III grade		V grade		pa-value		III grade		V grade		pa-value		III grade		V grade		pa-value
N		109		62				133		95				118		65
Dental caries		0 (1.5)		0 (1.25)		0.98		1.00 (3)		0 (3)		0.41		0 (2.25)		0 (4)		0.28
Caries treatment needs		1.00 (3)		0.50 (3)		0.63		2.00 (4)		1.00 (4)		0.19		0 (4)		2.00 (4)		0.02
OHI-S		1.00 (0.83)		0.58 (0.83)		0.004		1.00 (0.5)		1.00 (0.83)		0.75		0.50 (0.83)		1.00 (0.84)		<0.001
Overall knowledge		5 (6)		6 (6)		0.13		5 (6)		6 (5)		0.001		5 (7)		6 (6)		0.14

^aChi-square test