Table 1

Confounding variables adjusted for in the model.

Variable

Definition

Source

Geographic Level

Sex-specific

Race-specific


Age

10-year age groups from 35–44 to 75–84, and 85+

SEER

County

X

X

Poverty

% of households below poverty rate

2000 US Census

County

X

X

Income

Median household income in dollars

2000 US Census

County

X

Smoking

Age-adjusted lung and bronchus cancer mortality rate

SEER

County

X

X

Exercise

% with no exercise in last 30 days

BRFSS 1994–2002 (even years) & 2001

State

X

X

Alcohol

Average number of drinks in past 30 days

BRFSS 1997, 1999, 2001, 2002

State

X

X

Outdoor occupation

% of workers in agriculture, forestry, fishing, hunting, or construction

2000 US Census

County

X

Urban/rural

% rural population Average annual PM2.5 concentrationa

2000 US Census

County

Air quality

(values for ~ 600 counties known, remainder were interpolated)

US EPA AirNow database 2000

County


a Particulate matter results in an overestimation of surface-level ultraviolet exposure indicated by the TOMS data, since particulate matter absorbs ultraviolet radiation [46]

Boscoe and Schymura BMC Cancer 2006 6:264   doi:10.1186/1471-2407-6-264

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