Table 1.

Characteristics of colorectal cancer cases before age 50 years and controls at the index dates, 2006–2016

	Cases (n = 2,557)	Controls (n = 12,640)
Age, yr	42.9 (6.0)	42.9 (6.1)
Female, %	1,182 (46.2)	5,866 (46.3)
Year of diagnosis, %
2006–2007	438 (17.1)	2,173 (17.1)
2008–2010	722 (28.2)	3,577 (28.2)
2011–2013	782 (30.6)	3,877 (30.6)
≥2014	615 (24.1)	3,047 (24.0)
Educational attainment
≤9 yr	284 (11.0)	1,423 (11.3)
10–12 yr	1,280 (50.1)	6,216 (49.0)
≥13 yr	968 (37.9)	4,835 (38.1)
Unknown	25 (1.0)	200 (1.6)
Number of previous clinic visits	9.7 (16.2)	7.0 (12.4)
Number of previous hospitalizations	3.6 (5.5)	2.8 (4.8)
Number of previous lower endoscopies	0.2 (1.3)	0.02 (0.17)
Charlson Comorbidity Index	0.2 (0.9)	0.1 (0.5)

Mean (SD) is shown for continuous variables, and percentage is shown for categorical variables.