Table 1

 Characteristics of lung cancer cases and controls in Civitavecchia: frequency distribution, adjusted odds ratios (OR), and 95% confidence intervals (CI)

VariableCases (n = 234)Controls (n = 729)OR*95% CI
*Odds ratios adjusted for sex, age, year of death, and interaction between sex and age.
†Additionally adjusted for smoking habits.
‡Additionally adjusted for number of risk occupations.
§Additionally adjusted for education.
¶List B, occupations suspected to increase risk of lung cancer; List A, occupations known to increase risk of lung cancer.25
**Exposure to occupation considered to increase risk of lung cancer according to the International Agency for Research on Cancer (IARC) classification.2
††Traffic level was estimated through reported frequency of buses or lorries near residence of maximum length (low, never/rarely; medium, a few times a day; many times a day).
Age (years)
    60 to 699239.326336.1
    70 to 743314.112517.2
    Primary10846.133145.41.300.83 to 2.04
    Middle school3916.714219.51.110.64 to 1.91
    High school2510.7628.51.600.85 to 3.00
    University83.4223.01.670.65 to 4.24
    Other62.5162.21.390.48 to 4.03
    Missing 135.6192.6
Smoking habits (cigarettes/day)‡,§
    ⩽10187.79713.32.281.08 to 4.80
    11–207230.719927.34.642.48 to 8.69
    >2010645.321930.06.613.52 to 12.42
    Missing 73.013
Occupational history†,§,¶
    Never exposed17976.556577.51.00
    Ever list B/never list A2912.410614.50.820.51 to 1.32
    Ever exposed list A2611.1588.01.300.77 to 2.19
No. of occupations at risk†,§,**
    17130.322631.01.220.80 to 1.85
    ⩾27431.618225.01.490.97 to 2.31
Length of residence (years)†,‡,§
    >3015164.550268.90.810.58 to 1.14
Reported traffic level†,‡,§,††
    Medium2812.09312.70.860.53 to 1.39
    High5925.221529.50.820.57 to 1.78
    Missing 020.3
Area of residence†,‡,§
    City centre13658.447765.41.00
    Northern outskirts3515.09913.61.290.82 to 2.03
    Southern outskirts6226.615321.01.511.04 to 2.18