Study Demographic Data
  Total Active smokers Passive smokers Non-smokers  
Characteristic (n=293) (n=107) (n=86) (n=100)      P*
Age (years)         0.69
< 28 29.1 29.7 27.4 29.9
28-37 23.4 27.7 17.8 23.7
38-47 23.4 21.8 25 23.7
> 47 24.1 20.8 29.8 22.7
Race/Ethnicity         <0.01
White 46.5 51.5 34.1 51.5
Black 40.8 37.9 47.6 38.1
Asian 5.7 3.9 3.7 9.3
Mixed/Other 7 6.7 14.6 1.1
Education level         0.32
< high school 3.7 2.8 5.9 3
High School 19.1 16.8 20 20.2
Some college 25.2 30.8 28.2 17.2
College/technical 32.2 31.8 24.7 39.4
Professional 19.8 17.8 21.2 20.2
Household income         0.54
< 10,000 30.7 32 31 29
10,000-30,000 17.8 15.5 19 19
30,000-60,000 33.2 35 35.7 29
60,000-90,000 7 9.7 3.6 7
> 90,000 11.5 7.8 10.7 16
Marital status         <0.01
Single 73.7 81.3 69.8 72
Married 13 5.6 15.1 17
Has partner 4.3 7.5 3.5 0
Divorced/ separated/ widowed 9 5.6 11.6 11
*p values from chi-square test      
Table 1: Distribution of Data on study characteristics by smoking status on the day the serum was obtained.