Retention Rates on RBANS Memory

Rates of retention have shown usefulness in the diagnosis of Alzheimer disease,11-15 mild cognitive impairment (MCI), and those at risk for Alzheimer disease,13,14,16 epilepsy,17-20 traumatic brain injury,21,22 major depression,23 schizophrenia,15,20,24 and bipolar disorder.24 Clearly, the inclusion of retention rates as a distinct measure of cognition has clinical and research importance.25,26 The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS)27 is a recently developed battery of cognitive tests that has gained popularity as a screening instrument. The RBANS is designed to be a brief, repeatable, “stand-alone ” bat-tery tapping discrete neuropsychological domains, including attention, memory, language, and visuo-constructional skills. The RBANS provides more detailed assessment of cognitive domains than other screening measures of cognitive abilities commonly used in elderly patients with suspected impairments (eg, Mini-Mental State Examination,28 Dementia Memory problems are common across severalneurological and psychiatric conditions, butdissimilar patterns of immediate and delayed recall have been used to differentiate these conditions. For example, Alzheimer disease is a prototypical corti-cal dementia, with impairments in immediate and delayed recall and recognition.1 Conversely, subcorti-cal dementias, such as Huntington disease, are char-acterized by impaired immediate and delayed recall but relatively preserved recognition.2 Another pattern of memory performance that has been shown to be useful in discriminating among patient samples is per-cent retention or savings scores. Retention rates are the percent of information that is retained across time and have been calculated as delayed recall divided by immediate recall. Retention rates hav