Comparison of the original and parallel forms of the three words-three Shapes test

Abstract

Objective: The Three Words-Three Shapes test is a moderately difficult memory and learning test, which is very suitable for use in clinical applications. It allows the evaluation of both verbal and non-verbal materials in the same modality. Because neuropsychological evaluations may be repeated with certain intervals to follow a patient's progress, in situations where the progress of particularly degenerative diseases (e.g., Alzheimer or Parkinson-type dementia, primary progressive aphasia) need to be followed up, a parallel form of the test must be employed. Although normative data can be found for the original form of the test, the absence of data about the equivalency of its parallel form reduces the reliability of the test. Therefore, the aims of this study were to obtain normative data on the parallel form and compare the data on the parallel and original forms. Materials and Methods: One hundred-seventy nine participants aged 50 to 84 years with no neurologic or psychiatric disorders were included in the study. Pre-evaluations of potential participants were performed using the Standardized Mini-Mental State Examination and Geriatric Depression Scale, and the individuals who scored above the cut-off points set for Turkey were included in the study. Results: The average scores for the original and parallel forms of the test were found to have good agreement when they were applied with two-week intervals. According to the results of the correlation analysis, the correlation between incidental recall, acquisition and delayed recall subtests were significant. For the results that indicated no significant correlation for the copying and recognition subtests, separate charts of score frequencies are presented. Conclusion: The observed values indicate that both forms of the three words-three shapes test can be reliably employed in parallel.