Empirical validity of test procedures

Reitan's great concern has always been with the empirical validity of test procedures. Such validity can only be established by the collection of large amounts of data obtained from patients with reasonably complete documentation of their medical\neurological conditions. Both presence and absence of brain damage had to be well documented, and if present, findings related to site and type of lesion had to be established. He explained his work informally as one large experiment, necessitating maximal consistency in the process used, and to some extent, in the methods of analysing the data. Reitan and his many collaborators represent the group that was primarily responsible for the introduction of standard battery approach to clinical neuropsychology. It is clear from reviewing the Reitan group's work that there is substantial emphasis on performing controlled studies with samples sufficiently large to allow for the application of conventional statistical procedures