REPEATED EXPOSURE TO THE MINI-MENTAL-STATE-EXAMINATION AND THE INFORMATION-MEMORY-CONCENTRATION TEST-RESULTS IN A PRACTICE EFFECT IN ALZHEIMERS-DISEASE

We analyzed short-term variation of Mini-Mental State Examination (MMS E) and Information-Memory-Concentration (IMC) Test scores in 39 patien ts with Alzheimer's disease (AD), tested four times over 6 weeks. Alth ough analysis of variance had failed to show a significant ''learning' ' effect or other trends, we reexamined the data using repeated measur es models, with and without a learning effect. In the model without a learning effect, mean MMSE scores decreased minimally and mean IMC sco res decreased by 0.84 points over 6 weeks. In the model that allowed a potential learning effect between the first and second test sessions, scores increased significantly, by 1.12 +/-0.47 points for the MMSE a nd 1.04 +/- 0.43 points for the IMC Test. Patients' test scores predic ted from the models had less variability than did their raw scores. Th e short-term practice effect, although small, should be considered in interpreting changes in scores, especially in therapeutic studies in A D.