Table 4: Bivariate analysis used to evaluate the correlation between prevalence of fluorosis and the risk factors

		Prevalence of fluorosis
		Dean’s index 0				Dean’s index ≥ 1
Risk factors		No. of children		Percentage		No. of children		Percentage		χ2		p-value
Fluoride concentration
0.136 ppm		90		92.78		7		7.22		165.37		0.000001
0.381 ppm		42		42.42		57		57.58				S
1.36 ppm		0		0		93		100
Tea consumption/day
None		38		55.88		30		44.12		6.84		0.032
1 cup		46		49.46		47		50.54				S
2 cups or more		48		37.5		80		62.5
Diet
Veg		51		42.85		68		57.15		0.65		0.421
Mixed		81		47.64		89		52.36				NS
Nutritional status
Well-nourished		91		50.28		90		49.72		4.13		0.04
Malnourished		41		38.0		67		62				S
Breastfeeding
<1 year		2		100		0		0
1-2 years		128		45.7		157		54.3		2.41		0.300
2 years or above		2		100		0		0				NS
Water consumption/day
4-7 cups		10		55.6		8		44.2		13.23		0.0013
8-11 cups		100		51.8		93		48.2				S
12 cups and above		22		28.2		56		71.8

S: Significant; NS: Nonsignificant