Interestingly, the validation cohort included heterogeneous data from three studies in Scotland as well as two studies in different regions of Spain, using a number of different FIT analytical systems, and it appeared that the FAST score was equally clinically sensitive for CRC, regardless of country, prevalence of disease, age, sex, healthcare level (primary or secondary) and analytical system used to estimate f-Hb. The gene discussed is GSTM1; the disease is colorectal carcinoma.