BioPsychoSocial Assessment Tools for the Elderly - Assessment Summary Sheet

Test: Revised Dementia Rating Scale^TM (DRS)

Year: 1973

Domain: Biological/Psychological

Assessment Tool Category: Dementia

Variations/Translations: Dementia Rating Scale (DRS) – Original test, not used frequently

Setting: Clinical

Method of Delivery: Administered by a Neuropsychologist

Description: (DRS-2) is an enhanced version of the original DRS designed to provide standardized, quantitative cognitive functioning assessment in neurologically impaired populations. The 36- task and 32-stimulus card instrument is individually administered and designed to assess levels of cognitive functioning for individuals 55-89 years of age with brain dysfunction. The DRS-2 is sensitive at the lower ends of functioning and differentiating levels of severity deficits. Conversely, the instrument generally will not discriminate individual functioning in the average or higher range of intelligence due to the design to minimize floor effects of clinically impaired individuals. The initial pool of items from DRS was revised for comprehensive and brief administration allowing for a low floor so that even severely impaired individuals could be evaluated.  The DRS-2 has a wider age range than the original DSR, and the age corrected scaled and percentile ranks are more sensitive to change in cognitive status.  The task and stimulus card have not been changed from the original. In the hands of an experienced neuropsychologist-clinical psychologist, this is an excellent instrument but it is highly dependent upon the skills of each individual test administrator. The author recommends a qualification level of ‘B’ plus an advanced professional degree with relevant training in psychological testing. The DRS-2 tool consists of a professional manual, 50 scoring booklets, 50 profile forms and one set of 32-stimulus cards.

Scoring/Interpretation: The DRS-2 assesses cognitive functioning on five subscales: The following five subscales provide additional information on specific abilities: Attention (ATT, 8 items); Initiation/Perseveration (I/P, 11 items); Construction (CONST, 6 items); Conceptualization (CONCEPT, 6 items); and Memory (MEM, 5 items). Stimulus items contain material familiar to the majority of individuals.

Time to Administer: 10-15 minutes high functioning dementia patients, 30-40 minutes for low functioning dementia patients

Availability: Purchase at http://www3.parinc.com/products/product.aspx?Productid=DRS-2

Software: Included in the purchase

Website: http://www3.parinc.com/products/product.aspx?Productid=DRS-2

Quantitative/Qualitative: Quantitative

Validity (Quantitative): The reliability and validity properties of the DRS-2 are excellent. The DRS-2 was compared with the Mini-Mental State Examination (MMSE), which displayed a significant correlation (r = .82) with the DRS-2 showing a greater sensitivity to change than the MMSE in patients with severe dementia. In addition, correlations with the Wechsler Adult Intelligence Scale indicated a correlation of .75 between the WAIS full scale and the DRS-2 total score. A t test indicated no significant differences between scores on the two halves. The alpha coefficients were calculated for four DRS subscales using a combined dementia sample. The alpha coefficients were Attention (.95), Initiation-Perseveration (.87), Conceptualization (.95), and Memory (.75). Five factors were found; however, there is a confound of scoring dependence as patients who score positive on the initial items are given credit for the remaining items on the subtest, which results in an artificial correlation. The DRS-2 and Mini-Mental State Examination (MMSE) were administered to a sample of 65 residents living in a continuing care retirement community (30 residents with dementia, 35 residents without dementia) to demonstrate the construct and concurrent validity of the DRS-2 Total Score. A strong correlation was found between the MMSE and DRS-2 Total Score. When DRS-2 Total Scores were subjected to a discriminant function analysis, Total Scores accurately classified 61 of the 65 participants into the appropriate patient group (dementia vs. comparison). The results of these preliminary validation studies are robust, and suggest that the DRS-2 may be a useful measure when serial assessments with the DRS-2 are needed

Reliability (Quantitative): A test-retest reliability correlation coefficient was .97 with subscale correlation coefficients ranging from .61 to .94. The DRS was administered twice with a 1-week interval between administrations to a group of 30 patients diagnosed with dementia of the Alzheimer's type. A split-half reliability coefficient was .90, utilizing a sample of 25 patients aged 65-94 years who received diagnoses of either organic brain syndrome or senile dementia.

References:

Aarsland, D.,  Litvan, I.,  Salman, D.,  Galasko, D.,  Wentzel-Larsen, T. and Larsen, J.P. (2003). Performance on the Dementia Rating Scale in Parkinson's disease with dementia and dementia with lewy bodies: Comparison with progressive supra-nuclear palsy and Alzheimer's disease. Journal of Neurology, Neurosurgery, and Psychiatry 74(9), 1215-1220.

McDowell, I. & Newell, C. (1996). Measuring health: A guide to rating scales and questionnaires. (2nd ed.). New York: Oxford University Press.

Schmidt, K., Lieto, J., Kiryankova, E., & Salvucci, A. (2006). Construct and concurrent validity of the Dementia Rating Scale-2 alternate form. Journal of Clinical and Experimental Neuropsychology 28(5), 646-654.

Comments: The DRS-2 is very useful in the assessment and progression of dementia of the Alzheimer's type, vascular dementia, Parkinson's disease, Huntington's disease, and age-related dementia in individuals with mental retardation or Down’s syndrome.