Validity of different linguistic versions of the Alzheimer's disease Assessment Scale in an international multicentre Alzheimer's disease trial

Owing to the involvement of Italian Centres in a multicentre, German-Italia n therapeutical trial with Alzheimer's dementia patients, to be assessed wi th the Alzheimer's Disease Assessment Scale (ADAS), it was decided that the Italian centres would use an Italian version of the scale, derived from th at used by the German centres. However, the lists of words for exploring ve rbal memory are not merely translated from the German version, but are comp osed of selective Italian words chosen according to linguistic criteria, Th is Italian version was validated following the same procedure adopted for v alidating the German version, We submitted this Italian version to an inter rater reliability, test-retest reliability, concurrent validity, internal c onsistency and sensitivity evaluation, using demented patients, Based on th e results of these tests this Italian version of the ADAS proved valid and reliable. Moreover, the results were strikingly comparable to those from th e validation of the German version. Our work supports the validity, reliabi lity and transnational comparability of national versions of the ADAS const ructed following definite linguistic criteria.