Dr. Reifler commented in general about the difficulty of studying dementia and the behavioral disturbances associated with this disorder, particularly because these problems are not well defined. He speculated that Alzheimer's disease may ultimately be found to be more than one disease and that clinicians may be using different terminology to describe the same clinical phenomena. Dr. Reifler suggested that studying the assessment and treatment of the more easily definable behavioral syndromes might be a better approach than trying to tease out every possible behavioral disturbance.