Medicines and trials

The fortieth entry is l’efficacia sperimentale, and it sits exactly where English keeps two nouns and Italian keeps one. « Efficacy » is what a medicine does under trial conditions: patients chosen against a list, tablets counted, a protocol somebody is paid to follow. « Effectiveness » is what the same medicine does in a surgery, where the patient is older than anybody in the trial, takes four other things and stops in the third month. The two words are not stylistic variants. A regulator reads them as different quantities, and a sentence that swaps one for the other claims something the data never showed. Italian has the single noun l’efficacia and pins the sense with whatever follows it: l’efficacia sperimentale for the first, l’efficacia nella pratica clinica for the second, and a bare l’efficacia for neither in particular. So the traffic runs badly in both directions. Going into Italian, the adjective that the English noun carried inside it has to be said out loud; coming out, the reader has to decide which of the two English words a sentence without an adjective was entitled to.