As CDT measurement is not available within Scotland, it is recommended only when there is clinical difficulty in interpreting a normal or an abnormal GGT or other liver test result. King s College Hospital, London accept serum samples by post for CDT assay. Biological tests are of less value than self reports for screening with the intention of intervention. They have their greatest role where patients have a reason for minimising (or, less commonly, exaggerating) their consumption, and in monitoring patients progress in reducing their drinking. Even though these tests have limited sensitivity and specificity, if elevated in a given patient, they may help motivate a patient to.
