The assessment of changes in cognitive functioning: Age, education and gender specific Reliable Change Indices (RCIs) for older adults tested on the CERAD-NP battery. Results of the German Study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe)+)
Claudia Sikorski,
Janine
Stein, Melanie Luppa, Tobias Luck, Steffi G. Riedel-Heller,
Institut für Sozialmedizin, Arbeitsmedizin und Public Health (ISAP),
Arbeitsgruppe Public Health: Epidemiologie und Versorgungsforschung
Universität Leipzig
Wolfgang
Maier, Michael Wagner, Moritz Daerr,
Department of Psychiatry, University of
Bonn, Bonn
Hendrik van den Bussche, Thomas Zimmermann , Mirjam Köhler,
Institute
of Primary Medical Care, University Medical Center Hamburg-Eppendorf, Hamburg
Horst
Bickel, Edelgard Mösch,
Department of Psychiatry, Technical University
of Munich, Munich
Siegfried Weyerer,Teresa Kaufeler,
Central Institute of Mental Health, Mannheim
Michael Pentzek, Department of
General Practice, University Hospital Düsseldorf, Heinrich-Heine-University
Düsseldorf, Düsseldorf
Birgitt Wiese, Institute for Biometrics, Hannover
Medical School, Hannover
Anja Wollny, Institute of General Practice, Faculty
of Medicine, University of Rostock, Rostock
Hans-Helmut König,
Department
of Psychiatry, Health Economics Research Unit, University of Leipzig, Leipzig,
and Department of Medical Sociology and Health Economics, University Medical
Center Hamburg-Eppendorf, Hamburg
Background/Aims:
The diagnosis of dementia requires reliable evidence about
decline in cognitive functioning over time. The CERAD-NP battery represents
a commonly used neuropsychological instrument to measure cognitive functioning
in the elderly. Normative data for changes in cognitive function that normally
occur in cognitively healthy individuals is crucial to interpret changes
in CERAD-NP test scores. Methods: As part of the German Study on Ageing,
Cognition and Dementia in Primary Care Patients (AgeCoDe Study), a sample
of 1450 cognitively healthy individuals, aged 75 years and older, was assessed
three times at 1.5 year intervals over a period of 3 years using selected
subtests of the CERAD-NP battery. Age, education and gender specific reliable
change indices (RCIs) were computed for a 90% confidence interval. Results:
Across different age, education and gender subgroups, changes from at least
6 to 9 points in Verbal Fluency, 4 to 8 points in Word List Memory, 2 to
4 points in Word List Recall and 1 to 4 points in Word List Recognition
indicated significant (i.e. reliable) changes in CERAD-NP test scores at
the 90% confidence level. Conclusion: Smaller changes in CERAD-NP test
scores can be interpreted only with high uncertainty because of probable
measurement error, practice effects and normal age-related cognitive decline.
This study provides age, education and gender specific CERAD-NP reference
values for the interpretation of cognitive changes in older age groups.