Dement Geriatr Cogn Disord 2015;39:303–311 DOI: 10.1159/000375365 Accepted: January 17, 2015 Published online: March 18, 2015
© 2015 S. Karger AG, Basel 1420–8008/15/0396–0303$39.50/0 www.karger.com/dem
Original Research Article
Clinical Validity of the Mattis Dementia Rating Scale in Differentiating Mild Cognitive Impairment in Parkinson’s Disease and Normative Data Ondrej Bezdicek a Jiri Michalec b Tomas Nikolai a Jan Roth a Robert Jech a Evžen Růžička a
Petra Havránková a
a Department of Neurology and Centre of Clinical Neuroscience, and b Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
Key Words Dementia rating scale · Mild cognitive impairment · Normative data · Parkinson’s disease · Validity
Ondrej Bezdicek, PhD Department of Neurology and Centre of Clinical Neuroscience First Faculty of Medicine, Charles University and General University Hospital in Prague Kateřinská 30, CZ–128 21 Praha 2 (Czech Republic) E-Mail ondrej.bezdicek @ gmail.com
Downloaded by: University of Illinois at Chicago 128.248.155.225 - 5/4/2015 12:22:08 AM
Abstract Background/Aims: The aim of the present study was to provide normative data and determine the validity of the Czech version of the Mattis Dementia Rating Scale 2 (czDRS-2) in screening for mild cognitive impairment in Parkinson’s disease (PD-MCI) based on the Movement Disorder Society (MDS) Level II criteria. Methods: For validation purposes, 41 healthy controls (HC), 46 patients with PD-NI (Parkinson’s disease, no impairment) and 41 patients with PD-MCI (all groups assessed by the MDS Level II criteria for PD-MCI) were matched according to age and education. Results: With screening and diagnostic cutoff scores determined at ≤139 points, the czDRS-2 showed a sensitivity of 78% and a specificity of 88% in the detection of PD-MCI versus HC and a sensitivity of 78% and a specificity of 76% in the detection of PD-MCI versus PD-NI. The AUC (95% confidence interval) for the czDRS-2 was 84% (75–93) and 82% (73–91), respectively. We report percentile values for 286 subjects from the Czech population stratified by education level. Conclusion: Our results show that the czDRS-2 is a valid instrument at Level I for screening PD-MCI and support its construct validity and © 2015 S. Karger AG, Basel diagnostic equivalence in a cross-cultural setting.
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Dement Geriatr Cogn Disord 2015;39:303–311 DOI: 10.1159/000375365
© 2015 S. Karger AG, Basel www.karger.com/dem
Bezdicek et al.: Clinical Validity of the Mattis Dementia Rating Scale in Differentiating Mild Cognitive Impairment in Parkinson’s Disease and Normative Data
Introduction
Normative data are of critical importance for the meaningful interpretation of test scores [1, 2]. The cross-cultural comparison of standardized mental status instruments is greatly needed as it may bring information about construct equivalence and diagnostic validity in different cultural settings [3]. The Dementia Rating Scale 2 (DRS-2), formerly the Mattis Dementia Rating Scale [4, 5], is used to assess the general cognitive function in subjects at risk of dementia. A revised version with normative data and the new DRS-2 Alternate Form were published in 2001 without changes to the DRS test material [6, 7]. The DRS is a standard instrument in the cognitive research of neurodegenerative diseases and in Parkinson’s disease (PD) in particular [8] (referred to as a generic and non-PD-specific cognitive screening measure) [9]. The DRS has been recommended by the Movement Disorder Society (MDS) for the standard assessment of PD dementia at Level I (PD-D) [10] and, more recently, for mild cognitive impairment in PD at Level I (PD-MCI) [11]. Dubois et al. [10] suggested that a total score (≤135) should be used in the estimation of cognitive impairment in PD-D; however, they recommend the use of age- and education-based normative values. A cutoff value of
© 2015 S. Karger AG, Basel 1420–8008/15/0396–0303$39.50/0 www.karger.com/dem
Original Research Article
Clinical Validity of the Mattis Dementia Rating Scale in Differentiating Mild Cognitive Impairment in Parkinson’s Disease and Normative Data Ondrej Bezdicek a Jiri Michalec b Tomas Nikolai a Jan Roth a Robert Jech a Evžen Růžička a
Petra Havránková a
a Department of Neurology and Centre of Clinical Neuroscience, and b Department of Psychiatry, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
Key Words Dementia rating scale · Mild cognitive impairment · Normative data · Parkinson’s disease · Validity
Ondrej Bezdicek, PhD Department of Neurology and Centre of Clinical Neuroscience First Faculty of Medicine, Charles University and General University Hospital in Prague Kateřinská 30, CZ–128 21 Praha 2 (Czech Republic) E-Mail ondrej.bezdicek @ gmail.com
Downloaded by: University of Illinois at Chicago 128.248.155.225 - 5/4/2015 12:22:08 AM
Abstract Background/Aims: The aim of the present study was to provide normative data and determine the validity of the Czech version of the Mattis Dementia Rating Scale 2 (czDRS-2) in screening for mild cognitive impairment in Parkinson’s disease (PD-MCI) based on the Movement Disorder Society (MDS) Level II criteria. Methods: For validation purposes, 41 healthy controls (HC), 46 patients with PD-NI (Parkinson’s disease, no impairment) and 41 patients with PD-MCI (all groups assessed by the MDS Level II criteria for PD-MCI) were matched according to age and education. Results: With screening and diagnostic cutoff scores determined at ≤139 points, the czDRS-2 showed a sensitivity of 78% and a specificity of 88% in the detection of PD-MCI versus HC and a sensitivity of 78% and a specificity of 76% in the detection of PD-MCI versus PD-NI. The AUC (95% confidence interval) for the czDRS-2 was 84% (75–93) and 82% (73–91), respectively. We report percentile values for 286 subjects from the Czech population stratified by education level. Conclusion: Our results show that the czDRS-2 is a valid instrument at Level I for screening PD-MCI and support its construct validity and © 2015 S. Karger AG, Basel diagnostic equivalence in a cross-cultural setting.
304
Dement Geriatr Cogn Disord 2015;39:303–311 DOI: 10.1159/000375365
© 2015 S. Karger AG, Basel www.karger.com/dem
Bezdicek et al.: Clinical Validity of the Mattis Dementia Rating Scale in Differentiating Mild Cognitive Impairment in Parkinson’s Disease and Normative Data
Introduction
Normative data are of critical importance for the meaningful interpretation of test scores [1, 2]. The cross-cultural comparison of standardized mental status instruments is greatly needed as it may bring information about construct equivalence and diagnostic validity in different cultural settings [3]. The Dementia Rating Scale 2 (DRS-2), formerly the Mattis Dementia Rating Scale [4, 5], is used to assess the general cognitive function in subjects at risk of dementia. A revised version with normative data and the new DRS-2 Alternate Form were published in 2001 without changes to the DRS test material [6, 7]. The DRS is a standard instrument in the cognitive research of neurodegenerative diseases and in Parkinson’s disease (PD) in particular [8] (referred to as a generic and non-PD-specific cognitive screening measure) [9]. The DRS has been recommended by the Movement Disorder Society (MDS) for the standard assessment of PD dementia at Level I (PD-D) [10] and, more recently, for mild cognitive impairment in PD at Level I (PD-MCI) [11]. Dubois et al. [10] suggested that a total score (≤135) should be used in the estimation of cognitive impairment in PD-D; however, they recommend the use of age- and education-based normative values. A cutoff value of
