Math problem

They knew certain statistics about the disease (such as 50% survive after one year) that they either got through Junon's doctors or that they read up on (Junon's holding a journal on bone marrow transplantation in one scene), so Abel and Claude (mostly Claude, apparently a math whiz) could calculate from there what they wanted to know. I doubt having boards like that is common in France -- maybe Abel's hobby was impromptu math calculations ;)