Table 1

Demographic and clinical characteristics Early Lung Cancer Detection (ELCD) participants and non-participants and comparison with all Building Trades Medical Screening (BTMed) participants

CharacteristicAll BTMed participants
(n=21 488)*
ELCD programme invited (n=4399)
ELCD participants
(n=1290)
ELCD non-participants
(n=3109)
Mean age (SD)62.4 (12.5)65.2 (6.8)59.9 (8.6)†
Male sex (N, %)19 986 (93.0)1228 (95.2)2936 (94.4)
Race/ethnicity (N, %)‡
 White18 504 (86.1)1183 (91.7)2761 (88.8)†
 Black or African-American2118 (9.9)76 (5.9)264 (8.5)
 Other536 (2.5)18 (1.4)52 (1.7)
 Unknown or missing330 (1.5)13 (1.0)32 (1.0)
Spirometry, mean (SD)
 % predicted FEV1 84.8 (21.1)84.2 (19.0)81.8 (19.0)†
COPD prevalence (N, %)§3129 (15.3)205 (15.9)618 (20.3)†
Chest X-ray B-reader prevalence (N, %)
 Parenchymal changes (profusion ≥1/0)831 (4.0)78 (6.1)129 (4.4)†
 Pleural changes¶3079 (14.8)285 (22.1)387 (12.7)†
Cigarette smoking status at examination (N, %)
 Current smoker3589 (16.7)317 (24.6)1135 (36.5)†
 Past smoker9896 (46.1)936 (72.6)1838 (59.1)
 Never smoker7618 (35.5)37 (2.9)114 (3.7)
 Smoking unknown385 (1.8)0 (0.0)**22 (0.7)
Mean cigarette pack-years (SD)20.1 (25.6)36.0 (21.9)38.8 (24.6)†
Mean body mass index (SD)29.8 (5.4)29.6 (5.4)29.9 (5.3)
Years of DOE site work, mean (SD)8.8 (9.9)12.1 (11.4)8.9 (9.5)†
Years of construction work, mean (SD)22.4 (13.9)26.0 (12.0)24.5 (11.8)†
  • *Data for BTMed participants are based on their most current examination. Number and percent values are based workers with data for each measure. A total of 1153 workers lacked sufficient data to estimate pack-years of cigarette smoking.

  • †Data variable for participants statistically difference (p<0.05) based on a χ2 test of general association for categorical variables, Pearson χ2 test for proportions and analysis of variance or Wilcoxon rank-sum tests for continuous variables as appropriate.

  • ‡Some categorical variables may not add to 100% due to rounding.

  • §COPD was defined as a FEV1/FVC ratio below the Lower Limit of Normal using the prediction equations of Hankinson et al 44 without use of bronchodilation. Results shown for all spirometry meeting American Thoracic Society criteria.

  • ¶B-reader notations of findings of unilateral or bilateral pleural thickening consistent with pneumoconiosis.

  • **Smoking status updated at ELCD programme enrolment.

  • DOE, Department of Energy; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity.