Ultimately, a diagnosis serves a pragmatic cause: it should benefit patients. Patients, caregivers, and doctors alike wish that the whole diagnostic process is the first step to a complete cure. This ideal can almost never be accomplished for patients with signs of dementia. Of course, patients may also benefit substantially from symptomatic treatments, appropriate counseling, treatment of comorbidity, and interventions aimed at secondary prevention. To this end, the diagnostic process in dementia, or conditions that resemble dementia, should be aimed at careful delineation of symptoms and signs, identification of the various causes that contribute to the clinical picture, and description of all relevant comorbidity. In addition to a careful history taking and a thorough clinical examination, with special attention to the mental status examination, ancillary investigations may be of help. During this entire process, the emphasis should be on the identification of potentially reversible causes, not because they are highly prevalent but simply because the stakes are high.
Van Gool WA. Multiple-Level Studies Are Needed to Assess the True Value of Diagnostic Tests for Dementia. Arch Neurol. 2006;63(1):142-143. doi:10.1001/archneur.63.1.142