@article{ref1,
title="The performance index identifies changes across the dual task timed up and go test phases and impacts task-cost estimation in the oldest-old",
journal="Frontiers in human neuroscience",
year="2021",
author="Brauner, Fabiane Oliveira and Balbinot, Gustavo and Figueiredo, Anelise Ineu and Hausen, Daiane Oliveira and Schiavo, Aniuska and Mestriner, Regis Gemerasca",
volume="15",
number="",
pages="e720719-e720719",
abstract="INTRODUCTION: Dual tasking is common in activities of daily living (ADLs) and the ability to perform them usually declines with age. While cognitive aspects influence dual task (DT) performance, most DT-cost (DT-C) related metrics include only time- or speed- delta without weighting the accuracy of cognitive replies involved in the task. <br><br>OBJECTIVES: The primary study goal was to weight the accuracy of cognitive replies as a contributing factor when estimating DT-C using a new index of DT-C that considers the accuracy of cognitive replies (P-index) in the instrumented timed up and go test (iTUG). Secondarily, to correlate the novel P-index with domains of the Mini-Mental State Examination (MMSE). <br><br>METHODS: Sixty-three participants (≥85 years old) took part in this study. The single task (ST) and DT iTUG tests were performed in a semi-random order. Both the time taken to complete the task measured utilizing an inertial measurement unit (IMU), and the accuracy of the cognitive replies were used to create the novel P-index. Clinical and sociodemographic data were collected. <br><br>RESULTS: The accuracy of the cognitive replies changed across the iTUG phases, particularly between the walk 1 and walk 2 phases. Moreover, weighting 0.6 for delta-time (W(1)) and 0.4 for cognitive replies (W(2)) into the P-index enhanced the prediction of the MMSE score. The novel P-index was able to explain 37% of the scores obtained by the fallers in the &quot;spatial orientation&quot; and &quot;attention&quot; domains of the MMSE. The ability of the P-index to predict MMSE scores was not significantly influenced by age, schooling, and number of medicines in use. The Bland-Altman analysis indicated a substantial difference between the time-delta-based DT-C and P-index methods, which was within the limits of agreement. <br><br>CONCLUSIONS: The P-index incorporates the accuracy of cognitive replies when calculating the DT-C and better reflects the variance of the MMSE in comparison with the traditional time- or speed-delta approaches, thus providing an improved method to estimate the DT-C.<p /> <p>Language: en</p>",
language="en",
issn="1662-5161",
doi="10.3389/fnhum.2021.720719",
url="http://dx.doi.org/10.3389/fnhum.2021.720719"
}