Table 1

Characteristics of participants

Variable	Mean	SD
FEV₁ in litres	4.04	0.66
FEV₁% of predicted FEV₁	99.54	14.63
Height in metres	1.78	0.07
Weight in kilograms	82.50	13.55
Age at medical examination in years	38.33	2.52
Units of alcohol per week (median and IQR)	2.00	9.00
Standardised IQ score from enlistment	101.37	15.19

	Per cent
Ethnicity
White	82
Black	12
Other	6
Place of service
Vietnam	55
Other overseas	26
USA only	19
Smoking status
Smoker	46
Ex-smoker	28
Non-smoker	26
Education grade
≤11	12
12	37
>12	51
Household income midlife
≤$20 000	28
$20 000–$40 000	50
>$40 000	22
Marital status
Married	74
Divorced/separated/widowed	18
Never married	8
Physician-diagnosed chronic disease	13