Table 1 Selected characteristics of cases and controls
From: Serum selenium level and cancer risk: a nested case-control study
Variables | Case (n = 97) | Control (n = 184) | P |
|---|---|---|---|
Data blood draw, year (range) | 2011.8 (2009–2014) | 2012.3 (2010–2014) | < 0.0001 |
Date of cancer diagnosis, year (range) | 2013.3(2010.4–2014.8) | n/a | n/a |
Time from blood draw to diagnosis, months (range) | 17.91 (1.28–41.03) | n/a | |
Cancer site, n (%) | |||
Breast cancer | 53 (54.6%) | 0 | |
Ovarian cancer | 4 (4.1%) | 0 | |
Other cancer | 40 (41.2%) | 0 | n/a |
Cancer in first degree relatives, n (%) | |||
0 | 35 (36.1%) | 56 (30.4%) | |
1 | 37 (38.1%) | 76 (41.3%) | |
2 | 20 (20.6%) | 42 (22.8%) | |
> =3 | 5 (5.2%) | 10 (5.4%) | 0.82 |
Breast cancer in first degree relatives, n (%) | |||
0 | 84 (86.6%) | 153 (83.2%) | |
1 | 13 (13.4%) | 30 (16.3%) | |
2 | 0 | 1 (0.5%) | |
> =3 | 0 | 0 | 0.62 |
Smoking (current or past), n (%) | |||
No | 53 (54.6%) | 105 (56.0%) | |
Yes | 44 (43.4%) | 87 (44.0%) | 0.83 |