Table 4
Differences in nodule and participant characteristics between the PanCan data set2 and the NLST data set1 (p values, Student’s t-test or Wilcoxon-Mann-Whitney test or 
test used when appropriate). For each test, an effect size (ES) was also reported. For 
tests, Cramér’s V or 
was calculated (ie, magnitude of the ES; small: 
, medium: 
and large: 
) and for Student’s t-test and Wilcoxon-Mann-Whitney tests, 
and Cohen’s 
(ie, magnitude of the ES; small: 
, medium: 
and large: 
), respectively
| Nodule covariates | PanCan (n=7008) | NLST (n=7879) | P value | Effect size |
| Nodule size (mm) | 4.1 (3.1) | 6.89 (5.35) | <0.001 | 0.003 |
| Nodule type* | <0.001 † | 0.122 | ||
| Solid | 5511 (78.9%) | 7216 (91.59%) | ||
| Non-solid | 1105 (15.8%) | 485 (6.16%) | ||
| Part-solid | 303 (4.3%) | 178 (2.26%) | ||
| Perifissural | 70 (1.0%) | – | ||
| Nodule location (upper lobe)‡ | 3879 (55.70%) | 2710 (34.40%) | <0.001 | 0.21 |
| Nodule count at baseline | 6.2 (4) | 2.44 (1.63) | <0.001 | 0.733 |
| Spiculation | 197 (2.8%) | 1032 (13.1%) | <0.001 | 0.186 |
| Participant covariates | PanCan (n=1871) | NLST (n=5018) | P value | Effect size |
| Age (years) | 62.4 (5.8) | 62.01 (5.12) | <0.001 | 0.027 |
| Gender | <0.001 | 0.077 | ||
| Female | 886 (47.4%) | 1947 (38.80%) | ||
| Male | 985 (52.6%) | 3071 (61.20%) | ||
| Family history of lung cancer | 597 (32.4%) | 1154 (23.0%) | <0.001 | 0.091 |
| Emphysema | 1110 (60.4%) | 1661 (33.10%) | <0.001 | 0.238 |
*Only for 6989 nodules in PanCan data set.
†Test without perifissural category.
‡Only for 6964 nodules in PanCan data set.
NLST, National Lung Screening Trial; PanCan, Pan-Canadian Early Detection of Lung Cancer Study.