The prognostic value of integration of pretreatment serum amyloid A (SAA)–EBV DNA (S-D) grade in patients with nasopharyngeal carcinoma

Clinical and Translational Medicine

Table 3 The C-index of SAA, EBV DNA, S-D grade and TNM stage for prediction of OS

Factors	C-index (95% CI)	△C-index^a	P
SAA	0.631 (0.565–0.696)
EBV DNA	0.633 (0.566–0.700)
S-D grade	0.689 (0.623–0.754)
TNM stage	0.656 (0.590–0.723)
S-D grade vs SAA		0.058	0.062
S-D grade vs EBV DNA		0.056	0.030
SAA vs TNM stage		− 0.025	0.568
EBV DNA vs TNM stage		− 0.023	0.530
S-D grade vs TNM stage		0.032	0.441

Statistic indicate the changes in C statistic
C-index concordance index, CI confidence interval, S-D grade SAA-EBV DNA grade