Validity of Visuoconstructional Assessment Methods within Healthy Elderly Greek Australians: Quantitative and Error Analysis.

Abstract

Visuospatial skills are frequently assessed with drawing tests. Research has suggested that the use of drawing tasks in low educated groups may lack the ability to discriminate healthy individuals from clinical populations. The aims of this study were to investigate the validity of visuoconstructional tests in a sample of older Greek Australian immigrants and compare their performances to a matched sample of patients with Alzheimer's disease (ad). We assessed visuoconstructional performances in a sample of 90 healthy older Greek Australians, with a primary school level of education, and compared performances to a demographically matched sample of 20 Greek Australians with a diagnosis of ad on four visuoconstructional drawing tests: Greek cross, four-pointed star, intersecting pentagons, and the Necker Cube. While healthy participants tended to outperform the ad group on most copy tasks, high fail rates within the healthy sample were observed for the intersecting pentagons and Necker cube (78% and 73% fail rates, respectively) when using established clinical cut-off scores. High rates of curved angle, omission, distorted relation between elements, spatial disorganization and three-dimensional design errors were found across the four-pointed star, intersecting pentagons, and the Necker cube in both healthy participants and those with ad. Exploratory receiver operating characteristic curve analysis revealed that, with perhaps the exception of the Greek cross, meaningful sensitivity and specificity could not be reached for the four-pointed star, intersecting pentagons, and Necker cube. Cognitively healthy immigrants with low education appear to be at a disadvantage when completing visuoconstructional drawing tests, as their performance may be misinterpreted as indicating cognitive impairment. Future research is needed to identify alternative approaches to assess visuoconstructional ability in culturally and linguistically diverse older cohorts with limited education.