Clinical Dementia Rating

Last updated
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

The mini–mental state examination (MMSE) or Folstein test is a 30-point questionnaire that is used extensively in clinical and research settings to measure cognitive impairment. It is commonly used in medicine and allied health to screen for dementia. It is also used to estimate the severity and progression of cognitive impairment and to follow the course of cognitive changes in an individual over time; thus making it an effective way to document an individual's response to treatment. The MMSE's purpose has been not, on its own, to provide a diagnosis for any particular nosological entity.

A pain scale measures a patient's pain intensity or other features. Pain scales are a common communication tool in medical contexts, and are used in a variety of medical settings. Pain scales are a necessity to assist with better assessment of pain and patient screening. Pain measurements help determine the severity, type, and duration of the pain, and are used to make an accurate diagnosis, determine a treatment plan, and evaluate the effectiveness of treatment. Accurately measuring pain is a necessity in medical settings, especially if the pain measurement is going to be used as a screening tool, either for potential diseases or medical problems, or as a type of triage to determine urgency of one patient over another. Pain scales are based on trust, cartoons (behavioral), or imaginary data, and are available for neonates, infants, children, adolescents, adults, seniors, and persons whose communication is impaired. Pain assessments are often regarded as "the 5th Vital Sign".

Pupillometer, also spelled pupilometer, is a medical device intended to measure by reflected light the size of the pupil of the eye. In addition to measuring pupil size, current automated pupillometers may also be able to characterize pupillary light reflex. Some instruments for measuring pupillary distance (PD) are often, but incorrectly, referred to as pupilometers.

The clinical global impression (CGI) rating scales are measures of symptom severity, treatment response and the efficacy of treatments in treatment studies of patients with mental disorders. It is a brief 3-item observer-rated scale that can be used in clinical practice as well as in researches to track symptom changes. It was developed by Early Clinical Drug Evaluation Program (ECDEU) team of researchers for use in NIMH-led clinical trials that could provide clinical judgment based assessment for determining the severity of symptoms and the treatment progress. This was meant to assess the patient's functioning prior to and after initiating medication in trials which is an important part of study process. Its 3 items assess, 1) Severity of Illness (CGI-S), 2) Global Improvement (CGI-I), and 3) Efficacy Index. Many researchers, while recognizing the validity of the scale, consider it to be subjective as it requires the user of the scale to compare the subjects to typical patients in the clinician experience.

The Rancho Los Amigos Scale (RLAS), a.k.a. the Rancho Los Amigos Levels of Cognitive Functioning Scale (LOCF) or Rancho Scale, is a medical scale used to assess individuals after a closed head injury, including traumatic brain injury, based on cognitive and behavioural presentations as they emerge from coma. It is named after the Rancho Los Amigos National Rehabilitation Center, located in Downey, California, United States in Los Angeles County.

The Yale–Brown Obsessive–Compulsive Scale (Y-BOCS) is a test to rate the severity of obsessive–compulsive disorder (OCD) symptoms.

In statistics, inter-rater reliability is the degree of agreement among independent observers who rate, code, or assess the same phenomenon.

Leonard Berg was a neurologist at Washington University in St. Louis and a specialist in dementia and Alzheimer's disease. He was instrumental in the development of the Clinical Dementia Rating scale, a tool commonly used in research of these diseases.

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

Paratonia is the inability to relax muscles during muscle tone assessment. There are two types of paratonia: oppositional and facilitatory. Oppositional paratonia ("gegenhalten") occurs when subjects involuntarily resist passive movements, while facilitatory paratonia ("mitgehen") occurs when subjects involuntarily assist with passive movements.

Mild cognitive impairment (MCI) is a neurocognitive disorder which involves cognitive impairments beyond those expected based on an individual's age and education but which are not significant enough to interfere with instrumental activities of daily living. MCI may occur as a transitional stage between normal aging and dementia, especially Alzheimer's disease. It includes both memory and non-memory impairments. The cause of the disorder remains unclear, as well as both its prevention and treatment, with some 50 percent of people diagnosed with it going on to develop Alzheimer's disease within five years. The diagnosis can also serve as an early indicator for other types of dementia, although MCI may remain stable or even remit.

The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) is a questionnaire that can be filled out by a relative or other supporter of an older person to determine whether that person has declined in cognitive functioning. The IQCODE is used as a screening test for dementia. If the person is found to have significant cognitive decline, then this needs to be followed up with a medical examination to determine whether dementia is present.

<span class="mw-page-title-main">Beck Anxiety Inventory</span>

The Beck Anxiety Inventory (BAI), created by Aaron T. Beck and other colleagues, is a 21-question multiple-choice self-report inventory that is used for measuring the severity of anxiety in adolescents and adults ages 17 and older. The questions used in this measure ask about common symptoms of anxiety that the subject has had during the past week. It is designed for individuals who are of 17 years of age or older and takes 5 to 10 minutes to complete. Several studies have found the Beck Anxiety Inventory to be an accurate measure of anxiety symptoms in children and adults.

The California Verbal Learning Test (CVLT) is one of the most widely used neuropsychological tests in North America. As an instrument, it represents a relatively new approach to clinical psychology and the cognitive science of memory. It measures episodic verbal learning and memory, and demonstrates sensitivity to a range of clinical conditions. The test does this by attempting to link memory deficits with impaired performance on specific tasks. It assesses encoding, recall and recognition in a single modality of item presentation (auditory-verbal). The CVLT is considered to be a more sensitive measure of episodic memory than other verbal learning tests. It was designed to not only measure how much a subject learned, but also reveal strategies employed and the types of errors made. The CVLT indexes free and cued recall, serial position effects, semantic clustering, intrusions, interference and recognition. Delis et al. (1994) released the California Verbal Learning Test for Children (CVLT-C). The California Verbal Learning Test-II (CVLT-II) is an updated version of the original CVLT, which has been standardized and provides normative data.

The CDR computerized assessment system is a computerized battery of cognitive tests designed in the late 1970s by Professor Keith Wesnes at the University of Reading in Berkshire, England, for repeated testing in clinical trials. Task stimuli are presented in a laptop computer and participants respond via 'YES' and 'NO' buttons on a two-button response box, which records both the accuracy and reaction time.

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

The Montreal Cognitive Assessment (MoCA) is a widely used screening assessment for detecting cognitive impairment. It was created in 1996 by Ziad Nasreddine in Montreal, Quebec. It was validated in the setting of mild cognitive impairment (MCI), and has subsequently been adopted in numerous other clinical settings. This test consists of 30 points and takes 10 minutes for the individual to complete. The original English version is performed in seven steps, which may change in some countries dependent on education and culture. The basics of this test include short-term memory, executive function, attention, focus, and more.

The Luria–Nebraska Neuropsychological Battery (LNNB) is a standardized test that identifies neuropsychological deficiencies by measuring functioning on fourteen scales. It evaluates learning, experience, and cognitive skills. The test was created by Charles Golden in 1981 and based on previous work by Alexander Luria that emphasizes a qualitative instead of quantitative approach. The original, adult version is for use with ages fifteen and over, while the Luria–Nebraska Neuropsychological Battery for Children (LNNB-C) can be used with ages eight to twelve; both tests take two to three hours to administer. The LNNB has 269 items divided among fourteen scales, which are motor, rhythm, tactile, visual, receptive speech, expressive speech, writing, reading, arithmetic, memory, intellectual processes, pathognomonic, left hemisphere, and right hemisphere. The test is graded on scales that are correlated to regions of the brain to help identify which region may be damaged. The Luria–Nebraska has been found to be reliable and valid; it is comparable in this sense to other neuropsychological tests in its ability to differentiate between brain damage and mental illness. The test is used to diagnose and determine the nature of cognitive impairment, including the location of the brain damage, to understand the patient's brain structure and abilities, to pinpoint causes of behavior, and to help plan treatment.

Pupillometry, the measurement of pupil size and reactivity, is a key part of the clinical neurological exam for patients with a wide variety of neurological injuries. It is also used in psychology.

The Virtual Reality Functional Capacity Assessment Tool (VRFCAT) is a computerized measure that was developed to be a reliable, valid, and sensitive measure of functional capacity, with the potential to demonstrate real-world functional improvements associated with cognitive change. The VRFCAT presents participants with a realistic simulated environment to recreate routine activities of daily living. The VRFCAT was developed by VeraSci under National Institute of Mental Health (NIMH) Small Business Innovation Research (SBIR) phase 1 and phase 2 grants.

The Schizophrenia Cognition Rating Scale (SCoRS) is a 20 item interview-based clinical assessment that evaluates cognitive deficits and the degree to which these deficits impair patients’ day-to-day functioning. It was originally developed in 2001 at the Duke University Medical Center by Dr. Richard Keefe and is licensed through VeraSci. The SCoRS is used in clinical trials, academic research, and in clinical settings.

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).

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.