Confirmatory factor analysis of the Mattis Dementia Rating Scale in patients with Alzheimer's disease.

Abstract

Recent factor analyses of the Mattis Dementia Rating Scale (DRS; S. Mattis, 1973) have questioned the validity of its subscales, raising questions regarding their interpretation. This study examined the measurement structure of the standard DRS and of an abbreviated DRS form in a homogenous sample of 171 patients with Alzheimer's disease using (a) confirmatory factor analysis and (b) correlation of factors identified in the best fitting model with supplementary neuropsychological tests. We found confirmation of the validity of the Construction, Conceptualization, and Memory subscales associated with both the standard and abbreviated DRS. Correlations between these factors and supplementary neuropsychological measures supported the validity of the identified factors. The variability in DRS factor composition reported in previous studies appears to be related to sample heterogeneity, which is critically important to the resulting factor structure.The Mattis Dementia Rating Scale (DRS; Mattis, 1973) was designed to provide a brief assessment of cognitive abilities in patients "with known cortical impairment, particularly of the degenerative type" (Mattis, 1973, p. 1). Since its development, this measure has become one of the most popular instruments used to track cognitive changes in dementia patients. The test takes approximately 20-45 min to administer (Vitaliano et al., 1984). Reliability is high (van Belle, Uhlmann, Hughes, & Larson, 1990;Vitaliano et al., 1984) and portions of the DRS have been used to screen for dementia (Green, Woodard, & Green, 1995; Shay etal., 1991; Vitaliano etal., 1984). When combined with scores from the Instrumental Activities of Daily Living scale (IADL), patient assessments have been reported to closely approximate clinical judgments of dementia severity based on full clinical evaluation (Shay et al., 1991).The DRS includes items and provides cut-off scores for assessing specific cognitive domains including attention, initiation and perseveration, construction, conceptualization, and memory. Domain-specific scoring has the advantage of differentiating the strengths and weaknesses of an individual patient (Schmitt, Ranseen, & DeKosky, 1989

Cognitive profiles in dementia

“…23,24 The added complexity of the hybrid model accounted for more variance in the data and left less unexplained variance in the residual. This hybrid model resolves the conflicting results present in the literature [2][3][4][5][6][7][8][9] and eliminates the necessity of allowing different factor structures for people with and without AD.…”

“…These results converge with the hypothesis that the AD process is multifactorial and may have differential effects varying by individual as well as the stage of the disease. [7][8][9] This heterogeneity suggests that within the observed overall cognitive decline in AD there may exist discrete decrement profiles that mask one another when measured together. In addition to increased variance in the specific cognitive domains in AD, there was also a changed pattern of covariance between cognitive domains.…”

“…[7][8][9] Two CFA studies have compared individuals with and without dementia. One report concluded a general factor was sufficient for people with and without dementia, 10 while the other reported a multifactor fit for the two groups.…”

Clinical validity of the Chinese version of Mattis Dementia Rating Scale in differentiating dementia of Alzheimer's type in Hong Kong

“…Therefore, the Mattis Dementia Rating Scale (DRS), which samples a comprehensive range of cognitive functioning, may be considered as an alternative to these two scales to detect and characterize cognitive impairment (Salmon et al, 1990;Shay et al, 1991). The DRS is one of the standardized mental status examinations that is widely used in the United States (Lucas et al, 1998;Salmon et al, 1990;Woodard et al, 1996). The test is found to have impressive reliability, with a test-retest reliability of .97 (Mattis, 1988), split-half reliability of .90 (Gardner et al, 1981) and internal consistency ranging from .75 to .95 (Vitaliano et al, 1984).…”

Distinct cognitive profiles and rates of decline on the Mattis Dementia Rating Scale in autopsy-confirmed frontotemporal dementia and Alzheimer's disease

“…The MDRS is a widely used standardized mental status examination that provides a global measure of dementia derived from subscales for five cognitive capacities: attention, initiation and perseveration, construction, conceptualization, and memory. It is a reliable (Coblentz et al, 1973;Gardner et al, 1981;Smith et al, 1994;Vitaliano et al, 1984) and valid psychometric instrument for detecting and staging dementia (Gardner et al, 1981;Green et al, 1995;Monsch et al, 1995;Salmon et al, 1990;Shay et al, 1991;Smith et al, 1994;Troster et al, 1994;Woodard et al, 1996). Several studies have shown that the pattern of MDRS subscale scores can distinguish between AD and a variety of other dementing illnesses such as dementia with Lewy Bodies (DLB; Aarsland et al, 2003;Connor et al, 1998), Parkinson's disease (Paolo et al, 1995), Huntington's disease (Paulsen et al, 1995;Rosser & Hodges, 1994;Salmon et al, 1989), and progressive supranuclear palsy (Rosser & Hodges, 1994).…”