Table 4.

Correlation analysis for the acute and late xerostomia

Total:	2-year Xerostomia	P value
Acute Xerostomia (n = 170)	r = 0.325	P < 0.000
Late Xerostomia at 6 months	r = 0.566	P < 0.000
	5-year Xerostomia
Acute Xerostomia (n = 120)	r = 0.233	P = 0.005
Late Xerostomia at 6 months	r = 0.354	P < 0.000
Late Xerostomia at 2 years	r = 0.409	P < 0.000
Subgroup Analysis (Grade 3-4 Xerostomia at Acute)	2-year Xerostomia
Acute Xerostomia (n = 41)	r = -0.127	P = 0.214
Late Xerostomia at 6 months	r = 0.639	P < 0.000
	5-year Xerostomia
Acute Xerostomia (n = 29)	r = 0.141	P = 0.233
Late Xerostomia at 6 months	r = 0.538	P = 0.001
Late Xerostomia at 2 years	r = 0.732	P < 0.000