Abstract
Examined in a normal sample (N=365) the number of subjects was classified as impaired on several commonly used neuropsychological tests (Seashore Rhythm Test, Trail Making Test, Finger Tapping Test, and Grooved Pegboard Test) in reference to conventional cut-off scores. The sample was stratified on the basis of age, sex, and education. For the sample as a whole, the percentage of subjects classified as impaired ranged from 15.6 to 80. In some subgroups on some tests, the percentage so classified was 100. The data were discussed in relation to the need to adjust conventional cut-off scores for the influence of subject variables. In addition, cross-cultural differences on some tests suggested the need for local or national normative studies.