Psychometric tests can provide a sensitive and objective measure of dr
ug effects which are of relevance to the clinical situation. Two tests
, critical flicker fusion threshold and choice reaction time, used alo
ne or as a part of a battery of tests, have been shown to be useful in
detecting differences between drugs in their effect on cognitive and
psychomotor functions. They provide important information on the activ
ity and safety of drugs as they are used in practice.