THE COGNITIVE DRUG RESEARCH COMPUTERIZED ASSESSMENT SYSTEM IN THE EVALUATION OF EARLY DEMENTIA - IS SPEED OF THE ESSENCE

The cognitive drug research computerized assessment system (COGDRAS) w as evaluated in 98 unselected Hammer-smith Hospital Memory Clinic pati ents (mean age 64.9, range 28-83 years). They were divided into five g roups (worried well, depressed, demented, minimally cognitively impair ed and other brain disorders) on clinical assessment, Mini Mental Stat e Examination (MMSE) and Cambridge Cognitive Examination (CAMCOG) scor es. All but one patient completed the computer package, confirming its acceptability. The results of the COGDRAS in the five groups were ana lysed blind to diagnosis. The performance of the demented group was si gnificantly impaired in comparison with the worried well group, showin g that the COGDRAS is valid in mild dementia (mean MMSE 21.5, mean CAM COG 73.9). The depressed group tended to perform slightly less well th an the worried well, and the 'other' group showed a wide range of scor es consistent with its diversity. The minimally impaired had scores in termediate between the demented and worried well, but an interesting s peed/accuracy tradeoff was seen-patients appeared to maintain accuracy by taking longer to perform tasks. The heterogeneity of the minimally impaired group and the role of the measurement of task completion tim e in the diagnosis of early dementia are discussed.