Table 1. Selected baseline characteristics of the cases and controls, PLCO studya.

	Controls	Cases	P-value
N	380	380
Age at blood collection, years	64	64	Matched
Race, %
White, non-Hispanic	90.8	90.8
Black	4.5	4.5
Other races	4.7	4.7	Matched
PSA at blood draw (ng ml−1)	1.4	2.1	<0.0001
Height, cm	178.4 (2.7)	178.0 (2.6)	0.371
Weight, kg	87.0 (14.3)	87.0 (13.7)	0.930
BMI, kg m−2	27.4 (4.0)	27.5 (4.1)	0.659
Tobacco smoking status, %
Never smoker	37.9	43.2
Former smoker	56.3	52.4
Current smoker	5.8	4.5	0.29
Tobacco smoking duration,b years	25.1 (12.9)	23.9 (13.3)	0.272
Family history of prostate cancer, %	3.6	5.4	0.073
Diabetes, %	6.1	7.1	0.56
Physical activity at age 40 (h per week), %
4+ h (vs <3 h)	29.7	38.4	0.017

Abbreviations: PLCO=Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial; PSA=prostate-specific antigen; BMI=body mass index.

^aValues are means and standard deviations unless otherwise indicated.

^bTobacco smoking duration among current or former smokers.