Table 2.

Polynomial regression of schistosomiasis prevalence in two islands of Zanzibar according to year.

Polynomial Regression	Island	Equation Describing the Graph	R2
First order polynomial	Unguja	Y = −0.334x + 676.879	0.305
	Pemba	Y = −0.768x + 1552.778	0.798
Second order polynomial	Unguja	Y = 0.0152x2 − 61.44x + 62,287	0.309
	Pemba	Y = 0.0894x2 − 361.29x + 365,052	0.867
Third order polynomial	Unguja	Y = 0.0589x3 − 356.28x2 + 718,407x − 5 × 108	0.664
	Pemba	Y = 0.0018x3 − 10.957x2 + 21,913x − 1 × 107	0.867