Table 1.

Proportion (%) of diagnoses type for NPC incident cases, Mortality vs. incidence (M:I) ratios for males and females during different time periods in the Sihui and Cangwu Cancer Registries

Period	Diagnoses type in Sihui			Diagnosis type in Cangwu			M:I Ratio in Sihui		M:I Ratio in Cangwu
	Histological verification	Clinical deduction	Death certificate	Histological verification	Clinical deduction	Death certificate	Male	Female	Male	Female
1978–82	89.1	10.1	0.80	-	-	-	0.87	0.85	-	-
1983–87	89.6	9.50	0.90	95.5	2.41	2.06	0.71	0.64	0.70	0.67
1988–92	87.7	10.0	2.30	96.0	1.65	2.31	0.72	0.67	0.98	0.91
1993–97	85.2	13.0	1.80	96.5	2.02	1.44	0.70	0.76	0.95	1.00
1998–2002	90.3	8.90	0.80	97.3	1.06	1.60	0.71	0.59	0.76	0.65