Table 1.

A comparison of the clinical characteristics between the thyroid cancer and control study subjects

Characteristic	Total (n = 5,186)	Control (n = 5,133)	Thyroid cancer (n = 53)	p value
Age, yr	54.1 ± 9.1	54.1 ± 9.1	54.4 ± 10.3	0.792
Female sex	1,892 (36.5)	1,872 (36.5)	20 (37.7)	0.967
BMI, kg/m2	24.2 ± 3.2	24.2 ± 3.2	24.7 ± 3.3	0.290
Smoking	2,724 (52.6)	2,699 (52.6)	25 (47.2)	0.514
TSH, mU/La	1.9 ± 1.7	1.9 ± 1.7	1.8 ± 1.6	0.960
Free T4, ng/dL	1.3 ± 0.2	1.3 ± 0.2	1.3 ± 0.2	0.681
Health check-up seasons				0.871
Spring	1,496 (29)	1,480 (29)	16 (30)
Summer	1,504 (29)	1,487 (29)	17 (32)
Fall	1,175 (23)	1,163 (23)	12 (23)
Winter	1,006 (19)	998 (19)	8 (15)

Values are presented as mean ± SD or number (%).

BMI, body mass index; TSH, thyroid stimulating antibody; T4, thyroxine.

^aGeometric mean.