545 - Exploratory factor analysis of the Rowland Universal Dementia Assessment Scale.

Abstract

Background:Rowland Universal Dementia Assessment Scale (RUDAS) is a brief cognitive test, appropriate for people with minimum completed level of education and sensitive to multicultural contexts. It could be a good instrument for cognitive impairment (CI) screening in Primary Health Care (PHC). It comprises the following areas: recent memory, body orientation, praxis, executive functions and language.Research Objective:The objective of this study is to assess the construct validity of RUDAS analysing its internal consistency and factorial structure.Method:Internal consistency will be calculated using ordinal Cronbach’s α, which reflects the average inter-item correlation score and, as such, will increase when correlations between the items increase. Exploratory Factor Analysis will be used to arrange the variables in domains using principal components extraction. The factorial analysis will include the extraction of five factors reflecting the neuropsychological areas assessed by the test. The result will be rotated under Varimax procedure to ease interpretation.Exploratory factor analysis will be used to arrange the variables in domains using principal components extraction. The analysis will include Kaiser–Meyer–Olkin measure of sampling adequacy and Bartlett’s test of sphericity. Estimations will be based based on Pearson’s correlations between indicators using a principal component analysis and later replicated with a tetrachoric correlation matrix. The variance in the tetrachoric model will be analysed to indentify convergent iterations and their explicative power.Preliminary results of the ongoing study:RUDAS is being administered to 321 participants older than 65 years, from seven PHC physicians’ consultations in O Grove Health Center. The data collection will be finished by August 2021 and in this poster we will present the final results of the exploratory factor analysis.Conclusions:We expect that the results of the exploratory factor analysis will replicate the results of previous studies of construct validity of the test in which explanatory factor weights were between 0.57 and 0.82, and all were above 40%. Confirming that RUDAS has a strong factor construct with high factor weights and variance ratio, and 6-item model is appropriate for measurement will support its recommendation as a valid screening instrument for PHC.