The Clinical Dementia Rating

The Clinical Dementia Rating (CDR) is an instrument used to assess the presence and severity of dementia of the Alzheimer type (DAT); it may be applicable to other dementias as well. The CDR was developed at Washington University School of Medicine in 1982 and revised in 1993 to improve the distinction between different severity levels (see Appendix). Determination of the CDR is based on separate semi-structured interviews with the patient and an appropriate informant, such as spouse or adult child, to provide information regarding the patient's current level of cognitive function and daily activity in comparison with previously attained abilities.