The Extension of the German CERAD Neuropsychological Assessment Battery with Tests Assessing Subcortical, Executive and Frontal Functions Improves Accuracy in Dementia Diagnosis.

BACKGROUND/AIMS: Alzheimer's disease (AD) is the most common form of dementia. Neuropsychological assessment of individuals with AD primarily focuses on tests of cortical functioning. However, in clinical practice, the underlying pathologies of dementia are unknown, and a focus on cortical functioning may neglect other domains of cognition, including subcortical and executive functioning. The current study aimed to improve the diagnostic discrimination ability of the Consortium to Establish a Registry for Alzheimer's Disease - Neuropsychological Assessment Battery (CERAD-NAB) by adding three tests of executive functioning and mental speed (Trail Making Tests A and B, S-Words). METHODS: Logistic regression analyses of 594 normal controls (NC), 326 patients with mild AD and 224 patients with other types of dementia (OD) were carried out, and the area under the curve values were compared to those of CERAD-NAB alone. RESULTS: All comparisons except AD-OD (65.5%) showed excellent classification rates (NC-AD: 92.7%; NC-OD: 89.0%; NC-all patients: 91.0%) and a superior diagnostic accuracy of the extended version. CONCLUSION: Our findings suggest that these three tests provide a sensible addition to the CERAD-NAB and can improve neuropsychological diagnosis of dementia.

Comparison of verbal episodic memory measures: consortium to establish a registry for Alzheimer's disease--Neuropsychological Assessment Battery (CERAD-NAB) versus California Verbal Learning Test (CVLT).

Episodic memory is affected early in the course of dementia. Two well-established tests to assess verbal episodic memory functioning are the Word List task from the Consortium to Establish a Registry for Alzheimer's disease Neuropsychological Assessment Battery (CERAD-NAB) and the California Verbal Learning Test (CVLT). In clinical and/or research settings, patients are typically administered either one or the other test, making statistical comparisons difficult. This study aimed to (i) compare the z-scores of these two tests in patients with MCI and different types of dementia and (ii) establish formulae to transform CERAD-NAB scores into CVLT scores and vice versa. Sixty-five patients completed both tests for the first time and within 10 days of each other. Pearson correlation coefficients indicated that the two tests assess similar aspects of episodic memory and that the CVLT is more sensitive to subtle episodic memory impairments. Finally, conversion formulae are provided and their implementation illustrated.