Table 3 Distribution of patients and MLH1/MSH2 mutation carriers according to risk groups by the PREMM1,2 and the Barnetson models
Number of patients (n = 1222) (%)MLH1/MSH2 mutation carriers (%)*
PREMM1,2 score
<5%826 (68)– (–)
5–9%266 (22)2 (0.8)
10–19%98 (8)1 (1)
20–39%23 (2)3 (13)
⩾40%9 (0.7)2 (22)
Barnetson score
<0.5%873 (71)1 (0.1)
0.5–4%272 (22)1 (0.4)
5–19%48 (3.7)2 (4.2)
20–44%15 (1.2)1 (6.6)
⩾45%14 (1)3 (21)
  • *Percentages referred to each PREMM1,2 or Barnetson category.