From: The biography of the immune system and the control of cancer: from St Peregrine to contemporary vaccination strategies
Co-variable
Only BCG
Only vaccinia
Both
Age group
<50 years
0.23 (0.05-0.91) n = 25
0.31 (0.07-0.98) n = 111
0.27 (0.09-0.80) n = 299
≥50 years
0.74 (0.25-2.28) n = 20
0.69 (0.38-1.22) n = 362
0.48 (0.26-0.86) n = 313