Clinical validation of an aggregate learning ratio from the neuropsychological assessment battery.

Quantifying learning deficits provides valuable information in identifying and diagnosing mild cognitive impairment and dementia. Previous research has found that a learning ratio (LR) metric, derived from the list learning test from the Neuropsychological Assessment Battery (NAB), was able to distinguish between those with normal cognition versus memory impairment. The current study furthers the NAB LR research by validating a NAB story LR, as well as an aggregate LR. The aggregate LR was created by combining the individual list and story LRs. Participants were classified as those with normal cognition (n = 51), those with MCI (n = 39) and those with dementia (n = 35). Results revealed the story LR was able to accurately distinguish normal controls from those with mild cognitive impairment and those with dementia and offers enhanced discriminability beyond the story immediate recall score (sum of trial 1 and trial 2). Further, the aggregate LR provided superior discriminability beyond the individual list and story LRs and accounted for additional variance in diagnostic group classification. The NAB aggregate LR provides improved sensitivity in detecting declines in impaired learning, which may assist clinicians in making diagnoses earlier in a disease process, benefiting the individual through earlier interventions.

Performance on the African neuropsychology battery using the learning ratio in a sample of healthy Congolese.

OBJECTIVE: Using the African Neuropsychology Battery (ANB), we seek to develop normative data by examining the demographic effects for two learning process scores: initial learning (Trial One) and learning ratio (LR, the percentage of items learned relative of to-be-learned material following Trial 1). METHODS: Healthy participants from the Democratic Republic of Congo completed the four memory tests of the ANB: the African Story Memory Test (ASMT), African List Memory Test (ALMT), African Visuospatial Memory Test (AVMT), and African Contextual Visuospatial Memory Test (ACVMT). We developed indices of learning for each subtest, as well as aggregate learning indices for Trial 1 and LR, and composite indices examining verbal, visual, contextual, and noncontextual learning, and grand indices comprising all four subtests. RESULTS: Trial 1 and LR scores each demonstrated acceptable intercorrelations across memory tests. We present normative data for Trial 1 and LR by age and education. CONCLUSION: These data provide normative standards for evaluating learning in Sub-Saharan Africa.

Repeatable battery for the assessment of neuropsychological status and its relationship to biomarkers of Alzheimer's disease.

The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has been associated with commonly used biomarkers of Alzheimer's disease (AD). However, prior studies have typically utilized small and poorly characterized samples, and they have not analyzed the subtests of the RBANS. The current study sought to expand on prior work by examining the relationship between the Indexes and subtest scores of the RBANS and three AD biomarkers: amyloid deposition via positron emission tomography, hippocampal volume via magnetic resonance imaging, and APOE ε4 status.One-hundred twenty-one older adults across the AD continuum (intact, amnestic Mild Cognitive Impairment, mild AD), who were mostly Caucasian and well-educated, underwent assessment with the RBANS and collection of the three biomarkers.Greater amyloid deposition was significantly related to lower scores on all five Indexes and the Total Scale score of the RBANS, as well as 11 of 12 subtests. For bilateral hippocampal volume, significant correlations were observed for 4 of the 5 Indexes, Total Scale score, and 9 of 12 subtests, with smaller hippocampi being related to lower RBANS scores. Participants with at least one APOE ε4 allele had significantly lower scores on 3 of the 5 Indexes, Total Scale score, and 8 of the 12 subtests.In this sample of participants across the dementia spectrum, most RBANS Indexes and subtests showed relationships with the amyloid deposition, hippocampal volumes, and APOE status, with poorer performance on the RBANS being associated with biomarker positivity. Although memory scores on the RBANS have traditionally been linked to biomarkers in AD, other Index and subtest scores also hold promise as indicators of AD. Replication in a more diverse sample is needed.

Developing learning slope scores for the repeatable battery for the assessment of neuropsychological status.

Initial learning and learning slope are often acknowledged as important qualitative aspects of learning, but the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) contains discrete indices for neither. The traditional method of calculating learning slope involves a difference score between the last trial and first trial, which is referred to as raw learning score (RLS). However, this method does not account for initial Trial One performance and produces a ceiling effect that penalizes efficient first learners. We propose an alternative method of calculating learning score that accounts for initial learning performance, called learning ratio (LR), and we compared the psychometric and predictive properties of these methods. Performances from the List Learning and Story Memory subtests were used to create the indices, and composite learning scores were calculated by combining List Learning and Story Memory. The sample included 289 military veterans (mean age = 65.9 [12.6], education = 13.3 [2.4]), most of whom were male, undergoing neuropsychological assessments that included the RBANS. Results indicated that LR demonstrated superior correlations with criterion measures of memory when compared with RLS, and the LR composite score better discriminated between those with and without a neurocognitive diagnosis, AUC = 0.81 (0.76-0.87), than the RLS composite, AUC = 0.70 (0.64-0.76). We concluded that scores from the RBANS can be computed for initial learning and learning slope and that the LR method of calculating learning is superior to RLS in this older veteran sample.

Predicting biomarkers in intact older adults and those with amnestic Mild Cognitive Impairment, and mild Alzheimer's Disease using the Repeatable Battery for the Assessment of Neuropsychological Status.

INTRODUCTION: The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has been associated, to varying degrees, with commonly used biomarkers of Alzheimer's disease (AD). Given the ease of RBANS administration as a screening tool for clinical trials and other applications, a better understanding of how RBANS performance is associated with presence of APOE ε4 allele[s], cerebral amyloid burden, and hippocampal volume is warranted. METHOD: One hundred twenty-one older adults who were classified as intact, amnestic Mild Cognitive Impairment, or mild AD underwent cognitive assessment with the RBANS, genetic analysis, and quantitative brain imaging. APOE ε4 carrier status, 18F-Flutemetamol composite standardized uptake value ratio (SUVR), and hippocampal volume were each regressed on demographic variables and RBANS Total Scale score, Index scores, and subtest scores. RESULTS: Lower RBANS Total Scale score or Delayed Memory Index (DMI) predicted the presence of APOE ε4 allele[s], higher cerebral amyloid burden, and lower hippocampal volumes. DMI was a slightly better predictor than Total Scale score for most AD biomarkers. No demographic variables consistently contributed to these models. CONCLUSIONS: The RBANS - DMI in particular - is sensitive to AD pathology. As such, it could be used as a predictive tool, particularly in clinical drug trials to enrich samples prior to less accessible AD biomarker investigation.

Predicting Premorbid Scores on the Repeatable Battery for the Assessment of Neuropsychological Status and their Validation in an Elderly Sample.

OBJECTIVE: Assessing cognitive change during a single visit requires the comparison of estimated premorbid abilities and current neuropsychological functioning. Although premorbid intellect has been widely examined, premorbid expectations for other cognitive abilities have received less attention. The current study sought to develop and validate premorbid estimates for the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). METHOD: Using demographic variables and an estimate of premorbid intellect, premorbid performance on the RBANS was predicted in a sample of 143 community-dwelling, cognitively intact older adults. RESULTS: On all six Indexes of the RBANS, premorbid intellect was the best predictor of current cognitive functioning, with gender adding to one of the prediction models (R2 = 0.04-0.16, ps < .02). These prediction formulae were then applied to a sample of 122 individuals with amnestic Mild Cognitive Impairment to look for discrepancies between premorbid and current RBANS scores. Despite minimal differences between premorbid and current RBANS scores in the intact sample, large, and statistically significant differences were observed in the impaired sample, especially on the Immediate Memory Index (discrepancy = -29.00, p < .001), Delayed Memory Index (discrepancy = -32.28, p < .001), and Total Scale score (discrepancy = -25.58, p < .001). CONCLUSION: Although validation in larger samples is needed, the current estimates of premorbid RBANS abilities may aid clinicians in determining change across time.

Reliability of repeated cognitive assessment of dementia using a brief computerized battery.

OBJECTIVE: The aim of this study was to evaluate the short-term stability and reliability of a brief computerized cognitive battery in established dementia types. METHOD: Patients were administered the computerized battery twice with administrations approximately 2 hours apart, with intervening conventional neuropsychological tests. Patients were classified clinically, via consensus conference, as healthy controls (n = 23), mild cognitive impairment (n = 20), Alzheimer's disease (n = 52), dementia with Lewy Bodies ([DLB], n = 10), or frontotemporal dementia (n = 9). RESULTS: Minimal practice effects were evident across Cog-State test administrations. Small magnitude improvements were seen across all groups on a working memory task, and healthy controls showed a mild practice effect on the accuracy of associative learning. CONCLUSIONS: In established dementia, administration of the CogState tasks appears sensitive to cognitive impairment in dementia. Repeat administration also provided acceptable stability and test-retest reliability with minimal practice effects at short test-retest intervals despite intervening cognitive challenges.