Clinical differentiation of mental disorders in the eldery : validation of the CAMDEX
The present series of investigations examined the diagnostic accuracy of the Cognitive Examination (CAMCOG) from the Cambridge Mental Disorders of the Elderly Examination (CAMDEX) in the differential diagnosis of various dementing conditions. Specifically, this study examined: (a) the degree to which the CAMCOG would differentiate normal individuals from patients with Alzheimer's Disease (AD) and from those suffering from non-AD dementing conditions, (b) the extent to which the CAMCOG would distinguish between patients suffering from organic dementing conditions, those having functional psychiatric disorders, and normal persons, and (c) whether the CAMCOG would offer an improvement in diagnostic accuracy over a widely used screening instrument (i.e., the Mini-Mental Status Examination, MMSE) when attempting to differentially diagnose dementing patients and normal cohorts.A review of the literature was presented with an emphasis on the difficulties in establishing differential diagnosis, inaccuracies in diagnosis, the importance of improved diagnostic accuracy, and the use of neuropsychological measures in the assessment and diagnosis of patients suffering from dementing illnesses. Further, research relevant to ancillary diagnostic techniques, the various neuropsychologicalapproaches used in evaluating and diagnosing mental disorders in the elderly, and studies investigating the utility of specific cognitive/neuropsychological measures in the differential diagnosis of dementing diseases was presented.The results of these investigations revealed that the CAMCOG provides excellent diagnostic sensitivity and specificity when differentiating normal persons from clinically diagnosed AD patients and when distinguishing between individuals with an organic-dementing condition and normal adults. The CAMCOG was found to be less effective in differentiating AD and non-AD dementia patients and in distinguishing between patients suffering from organic dementia versus specified psychiatric disorders. Finally, the CAMCOG demonstrated a slight improvement in diagnostic accuracy over the Mini-Mental Status Examination. These results were discussed in terms of their support for the utility of the CAMCOG as an excellent screening measure when used to differentiate patients suffering from various dementia-producing disease states and normal persons.