Robustness of reliable change indices to variability in Parkinson’s disease with mild cognitive impairment

Recent Advances in Neuropsychological Test Interpretation for Clinical Practice

Much attention in the field of clinical neuropsychology has focused on adapting to the modern healthcare environment by advancing telehealth and promoting technological innovation in assessment. Perhaps as important (but less discussed) are advances in the development and interpretation of normative neuropsychological test data. These techniques can yield improvement in diagnostic decision-making and treatment planning with little additional cost. Brooks and colleagues (Can Psychol 50: 196-209, 2009) eloquently summarized best practices in normative data creation and interpretation, providing a practical overview of norm development, measurement error, the base rates of low scores, and methods for assessing change. Since the publication of this seminal work, there have been several important advances in research on development and interpretation of normative neuropsychological test data, which may be less familiar to the practicing clinician. Specifically, we provide a review of the literature on regression-based normed scores, item response theory, multivariate base rates, summary/factor scores, cognitive intraindividual variability, and measuring change over time. For each topic, we include (1) an overview of the method, (2) a rapid review of the recent literature, (3) a relevant case example, and (4) a discussion of limitations and controversies. Our goal was to provide a primer for use of normative neuropsychological test data in neuropsychological practice.

The role of noradrenaline in cognition and cognitive disorders

Many aspects of cognition and behaviour are regulated by noradrenergic projections to the forebrain originating from the locus coeruleus, acting through alpha and beta adrenoreceptors. Loss of these projections is common in neurodegenerative diseases and contributes to their cognitive and behavioural deficits. We review the evidence for a noradrenergic modulation of cognition in its contribution to Alzheimer's disease, Parkinson's disease and other cognitive disorders. We discuss the advances in human imaging and computational methods that quantify the locus coeruleus and its function in humans, and highlight the potential for new noradrenergic treatment strategies.

Measuring reliable change in traumatic brain injury (TBI): The pitfalls of using readily available formulae

Individuals with a traumatic brain injury (TBI) frequently undergo repeat neuropsychological assessments. Reliable change (RC) methodologies based on general population normative data are often used to assess for clinically significant change. The consequence of applying such methodologies to an individual with a TBI needs investigation. The current study tested the validity of readily available formulae in moderate to severe TBI participants who were >2 years postinjury. Participants were administered the Wechsler Adult Intelligence Scale-IV/Wechsler Memory Scale-IV (WAIS/WMS-IV) battery on two occasions across an approximate 1 year interval. Index scores were entered into 10 RC formulae to assess their validity in individuals with a TBI. Findings revealed that the formulae used in the study are relatively interchangeable in regards to WAIS-IV assessment, but that many of the formulae identified statistically unexpected rates of RC change in memory tasks assessed by the WMS-IV. Two formulae that did not contain statistical manipulations for practice effects performed relatively well in regards to memory assessment. Therefore, indiscriminate use of RC formulae could lead to over identifying memory decline in the TBI populations. The results suggest that either Iverson or Jacobson and Truax formulae can be used to assess RC for memory in moderate to severe TBI populations.