Clinical Dementia Rating

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Clinical Dementia Rating
Purposemeasures severity of symptoms of dementia

The Clinical Dementia Rating or CDR is a numeric scale used to quantify the severity of symptoms of dementia (i.e. its 'stage').

Contents

Scale

Using a structured-interview protocol developed by Charles Hughes, [1] Leonard Berg, John C. Morris and other colleagues at Washington University School of Medicine, a qualified health professional assesses a patient's cognitive and functional performance in six areas: memory, orientation, judgment & problem solving, community affairs, home & hobbies, and personal care. Scores in each of these are combined to obtain a composite score ranging from 0 through 3. [2] Clinical Dementia Rating Assignment Qualitative equivalences are as follows:NACC Clinical Dementia Rating

Composite RatingSymptoms
0none
0.5very mild
1mild
2moderate
3severe

CDR is credited with being able to discern very mild impairments, but its weaknesses include the amount of time it takes to administer, its ultimate reliance on subjective assessment, and relative inability to capture changes over time. [3]

Validity

While the assessment is ultimately subjective in nature, recent studies have suggested a very high interrater reliability. [4] Thus the CDR is a reliable and valid tool for assessing and staging dementia. [5]

Importance

With increasing clinical focus on dementia, there is likewise increasing interest in pharmacology in the development of drugs to halt, or slow the progression of dementia-related illness such as Alzheimer's Disease. Therefore, early and accurate diagnosis of dementia and staging can be essential to proper clinical care. Without the ability to reliably assess dementia across the board, the misuse of anti-dementia compounds could have negative consequences, such as patients receiving the wrong medication, or not receiving treatment in the early stages of dementia when it is most needed. [6]

Related Research Articles

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<span class="mw-page-title-main">Paratonia</span>

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<span class="mw-page-title-main">Montreal Cognitive Assessment</span> Screening assessment for detecting cognitive impairment

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See also: University of California, San Diego Performance-Based Skills Assessment

Clinicians routinely check the pupils of critically injured and ill patients to monitor neurological status. However, manual pupil measurements have been shown to be subjective, inaccurate, and not repeatable or consistent. Automated assessment of the pupillary light reflex has emerged as an objective means of measuring pupillary reactivity across a range of neurological diseases, including stroke, traumatic brain injury and edema, tumoral herniation syndromes, and sports or war injuries. Automated pupillometers are used to assess an array of objective pupillary variables including size, constriction velocity, latency, and dilation velocity, which are normalized and standardized to compute an indexed score such as the Neurological Pupil index (NPi).

The Tourette's Disorder Scale (TODS) is a psychological measure used to assess tics and co-occurring conditions in Tourette syndrome, a disease characterised by simple and complex motor and vocal tics and a wide range of behavioural and emotional symptoms. There are two versions of TODS (TODS-CR and TODS-PR), each being a 15-item scale that helps clinicians evaluate the severity of various symptoms associated with tics, inattention, hyperactivity, obsessions, compulsions, aggression and emotions.

References

  1. Br J Psychiatry. 1982 Jun;140:566-72. A new clinical scale for the staging of dementia. Hughes CP, Berg L, Danziger WL, Coben LA, Martin RL.
  2. "Clinical Dementia Rating Assignment".
  3. Utility of the Clinical Dementia Rating in Asian Populations - Lim et al. 5 (1): 61 - Clinical Medicine & Research
  4. Rockwood, K.; Strang, D.; MacKnight, C.; Downer, R.; Morris, J. C. (2000). "Interrater reliability of the Clinical Dementia Rating in a multicenter trial". Journal of the American Geriatrics Society. 48 (5): 558–9. doi:10.1111/j.1532-5415.2000.tb05004.x. PMID   10811551. S2CID   31522657.
  5. Nyunt, Ma Shwe Zin; Chong, Mei Sian; Lim, Wee Shiong; Lee, Tih Shih; Yap, Philip; Ng, Tze Pin (2013-10-29). "Reliability and Validity of the Clinical Dementia Rating for Community-Living Elderly Subjects without an Informant". Dementia and Geriatric Cognitive Disorders Extra. 3 (1): 407–416. doi:10.1159/000355122. ISSN   1664-5464. PMC   3843919 . PMID   24348502.
  6. Morris, J. C.; Ernesto, C.; Schafer, K.; Coats, M.; Leon, S.; Sano, M.; Thal, L. J.; Woodbury, P. (1997). "Clinical Dementia Rating training and reliability in multicenter studies". Neurology. 48 (6): 1508–1510. doi:10.1212/WNL.48.6.1508. PMID   9191756. S2CID   41691732.