The Towers of Kuwait-Arabic Neurocognitive Assessment (ToK-ArNA): Preliminary normative data and test-retest reliability in Omani adults aged 50 years and above.

Abstract

The Towers of Kuwait-Arabic Neurocognitive Assessment (ToK-ArNA) was developed as a culturally relevant tool to assess executive functions (EF) and visuospatial (VS) abilities in the Omani population. This study established demographically adjusted normative data and evaluated the instrument's temporal stability through formal test-retest reliability analyses. A community sample of 138 cognitively intact Omani adults aged 50 years and above was enrolled. The ToK-ArNA consists of 12 problems scored independently for Time and Accuracy. Normative data were generated using multiple linear regression analysis and traditional stratification by sex, age group (50-64 vs. ≥ 65 years) and education level (0-5 vs. ≥ 6 years). Test-retest reliability was evaluated in a subsample (n = 29) across a 7-10 days interval using intraclass correlation coefficients (ICCs) and Pearson's correlations (r). Both age and education level significantly influenced time and accuracy scores across analyses (p < 0.001), with younger and more educated participants performing better. Sex was significantly associated with accuracy scores in the univariate analysis only, where men outperformed women. Test-retest reliability was good for Time scores (ICC = 0.76, r = 0.76, p < 0.001) but moderate for Accuracy scores (ICC = 0.45, r = 0.47, p = 0.010). This study provides the first normative framework for the ToK-ArNA, enhancing its clinical diagnostic utility. The findings demonstrate that age and education strongly affect executive performance, highlighting the necessity of demographically adjusted norms. The instrument exhibits acceptable temporal stability, particularly for Omani adults aged 50-65 years.