The optimal immunochemical test to use for generalised mass screening is still under debate in France. To compare the cost and effectiveness in biennial screening for colorectal cancer of fifteen strategies consisting of the three-stool sample un-rehydrated guaiac faecal occult blood test and three immunochemical tests: Magstream, FOB-Gold and OC-Sensor, at different positivity cut-off levels and stool-sample collection. A Markov model was used to compare these strategies in a general population of 100,000 individuals aged 50-74 over a 20-year period. Immunochemical tests were efficient strategies compared with guaiac faecal occult blood test. When all 15 strategies were compared with each other, only five of them remained efficient: the one- and two-stool sample Magstream, the one- and two-stool sample FOB-Gold with the 176 ng/mL cut-off, and the two-stool sample OC-Sensor with the 150 ng/mL cut-off. Sensitivity analyses showed that, at an identical price, the one-stool sample OC-Sensor was the most efficient strategy, and outperformed FOB-Gold. One-stool immunochemical testing can be considered a promising alternative to the guaiac faecal occult blood test for colorectal cancer mass screening in the general population. Competition between manufacturers should now be introduced to reduce purchase price differences. Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.