Table 1.

Proportion (frequency) of missing observations in Dukes’ stage by dichotomised age and postoperative mortality

	30 Day Postoperative Mortality
Age at Diagnosis	Alive	Deceased
Less than or equal to 70 years old	0.16 (11,453)	0.25 (548)
Greater than 70 years old	0.14 (10,539)	0.22 (1,894)