Enhancing precision of the Telephone Interview for Cognitive Status-Modified (TICS-M) using the Rasch model

The Telephone Interview for Cognitive Status-modified (TICS-M) is a well-established and widely used screening instrument for dementia and assessment of global cognitive function in older people. This study aimed to evaluate the psychometric properties of the TICS-M and to enhance the accuracy of the instrument using Rasch methodology. Partial Credit Rasch model was applied to the TICS-M scores. The sample selected for Rasch analysis consisted of 432 participants aged 70-90 years (M = 78.85, SD = 4.73) including 195 males (237 females), and 132 (30.56%) of whom were diagnosed with dementia after the baseline assessment. Initial analysis indicated good reliability of the TICS-M assessment scores, but there were three misfitting items and local dependency issues. Combining locally dependent and misfitting items into super-items achieved the best Rasch model fit for the TICS-M. This modification improved reliability of the assessment scores and resulted in no misfitting items, no local dependency, strict unidimensionality, and invariance across individual factors such as participants age, sex, diagnosis, and in-person neuropsychological assessment scores. Satisfying Rasch model expectations allowed for creation of a transformation table to convert raw TICS-M scores into interval-level data, which improves precision of the instrument. In summary, the TICS-M assessment scores demonstrated excellent reliability as reflected by Person Separation Index (PSI = 0.86) and met expectations of the unidimensional Rasch model after minor adjustments. The ordinal-to-interval transformation table can be used to increase accuracy of the TICS-M without altering its current format. These findings contribute to more accurate assessments of cognitive decline in older people and screening for conditions such as dementia. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

A Comprehensive Review of the Quality and Feasibility of Dementia Assessment Measures: The Dementia Outcomes Measurement Suite

The diagnosis of dementia and the management of its associated symptoms are aided by high-quality assessment tools. However, there is disagreement on the optimal tools among abundant alternatives and lack of consistent quality standards across the different domains of dementia-related change (ie, cognition, severity, function, behavioral and psychological symptoms, delirium, quality of life). Standardization is difficult because the relevance of a measurement tool for health professionals may depend on the clinical setting and on the dementia type and severity. To address this need, we conducted a comprehensive and clinically relevant evidence-based review of dementia-related tools and present a set of recommended tools, the Dementia Outcomes Measurement Suite. The review revealed that considerable development has occurred in terms of assessment of persons with mild cognitive impairment, executive dysfunction, cognitively mediated functional change, and apathy. More research is needed to develop and validate tools to assess health-related quality of life and specific symptoms of dementia including anxiety, wandering, and repetitive vocalizations. This extensive overview of the quality of different measures may serve as a guide for health professionals clinically and for researchers developing new or improved dementia assessment tools.

Discriminating Audiovisual Speed: Optimal Integration of Speed Defaults to Probability Summation When Component Reliabilities Diverge

We investigated audiovisual speed perception to test the maximum-likelihood-estimation (MLE) model of multisensory integration. According to MLE, audiovisual speed perception will be based on a weighted average of visual and auditory speed estimates, with each component weighted by its inverse variance, a statistically optimal combination that produces a fused estimate with minimised variance and thereby affords maximal discrimination. We use virtual auditory space to create ecologically valid auditory motion, together with visual apparent motion around an array of 63 LEDs. To degrade the usual dominance of vision over audition, we added positional jitter to the motion sequences, and also measured peripheral trajectories. Both factors degraded visual speed discrimination, while auditory speed perception was unaffected by trajectory location. In the bimodal conditions, a speed conflict was introduced (48° versus 60° s−1) and two measures were taken: perceived audiovisual speed, and the precision (variability) of audiovisual speed discrimination. These measures showed only a weak tendency to follow MLE predictions. However, splitting the data into two groups based on whether the unimodal component weights were similar or disparate revealed interesting findings: similarly weighted components were integrated in a manner closely matching MLE predictions, while dissimilarity weighted components (greater than 3: 1 difference) were integrated according to probability-summation predictions. These results suggest that different multisensory integration strategies may be implemented depending on relative component reliabilities, with MLE integration vetoed when component weights are highly disparate.