0 = male
1 = female

1 = white
2 = black
3 = other

Hispanic ethnicity
0 = no
1 = yes

Income group (quintile)
1 = very low
2 = low
3 = medium
4 = high
5 = very high

Education level
1 = less than HS
2 = HS graduate
3 = some college
4 = college graduate

Region of residence
1 = north
2 = south
3 = east
4 = west

Diabetes status
1 = normal
2 = prediabetes
3 = diabetes

Lung cancer stage
0 = no cancer
1 = Stage 1
2 = Stage 2
3 = Stage 3
4 = Stage 4