Alzheimer’s Disease Research Center (ADRC)

John C. Morris, M.D., Principal Investigator & Co-Director

Washington University School of Medicine, St. Louis, Missouri, USA

The CDR is a clinical staging instrument for dementia. It characterizes six domains of cognitive and functional performance: Memory, Orientation, Judgment & Problem Solving, Community Affairs, Home & Hobbies, and Personal Care. The necessary information to make each rating is obtained through a semi-structured interview of the patient and a reliable informant or collateral source (e.g., a family member). The CDR Table provides descriptive anchors that guide the clinician in making appropriate ratings based on interview data and clinical judgment. In addition to ratings on a 5-point scale for each domain (except Personal Care, which is rated on a 4-point scale) an overall CDR score is derived by standard algorithm. This score is useful for globally staging the level of impairment: 0 = No impairment, 0.5, 1, 2, and 3 indicate Very Mild, Mild, Moderate and Severe Dementia.

Morris J.C. The Clinical Dementia Rating (CDR): Current version and scoring rules. Neurology,1993; 43:2412-2414. The scoring algorithm can be accessed at http://www.biostat.wustl.edu/~adrc/cdrpgm/index.html.

The CDR is used in both research and clinical settings to characterize the level of cognitive and functional performance in patients at risk for or suspected of having Alzheimer’s Disease or another dementing disorder. Common applications include patient evaluation in memory assessment clinics, research studies of normal elderly and those with dementia, and clinical trials of therapeutic agents that might influence dementia progression.

The CDR is based on information elicited through a semi-structured interview standardized in an assessment protocol. Clinical skills to elicit appropriate information and judge its relevance are required. Physicians and advanced practice nurses administer the protocol and score the CDR in our center. Physicians and non-physician health professionals demonstrate good reliability in administering the CDR after appropriate training. (Morris JC, Ernesto C, Schafer K, et. al. Clinical Dementia Rating training and reliability in multi-center studies: The Alzheimer's Disease Cooperative Study experience. Neurology 1997; 48:1508-1510.)

The Brief Training and Reliability Protocol (BTRP) includes an introduction to the CDR by Dr. John Morris, three videotaped patient interviews for training purposes, and six videotaped interviews for reliability certification. Successful completion of the 6 reliability tapes is achieved with agreement with a "gold standard" on at least 5 out of the 6 tapes. Alternatively, the ADRC offers mini-fellowships in the CDR where in on-site observations of the CDR with actual patients by a CDR-experienced clinician permits individual instruction.

The Brief Training & Reliability Protocol (BTRP) for the CDR is available for browsing and formal reliability training through the ADRC Website. Individual health professionals and researchers are welcome to use this system free of charge. Fees may apply for commercial and group users, however. To access the system and related documentation, go to http://alzheimer.wustl.edu/, click on the Clinical Dementia Rating link in the Education Menu, and then follow the instructions to access the training modules. Full training through the BTRP requires 6-9 hours, but this can be broken up over multiple sittings. This system is made possible through funding from the National Institute on Aging (P50-AG05681).