CERAD Neuropsychological Battery-Arabic Version: Regression-Based and Stratified Normative Data and Effects of Demographic Variables on Cognitive Performance in Older Omanis

BACKGROUND AND OBJECTIVES Normative data on cognitive performance for the Omani population are scarce. In this study, we tested a sample of older (≥50 years) community-dwelling Omanis on the Consortium to Establish a Registry for Alzheimer's Disease neuropsychological battery-Arabic version (CERAD-ArNB). We analyzed the participants' cognitive performance and how it was affected by their sex, age, and level of education. METHODS We enrolled 150 older Arabic-speaking Omanis from March 2014 to June 2015. Most of the participants were visitors to patients admitted to a tertiary referral center in the Sultanate of Oman. All participants underwent screening to ensure normal cognitive function before taking the CERAD-ArNB. We used multiple regression analysis and stratification according to demographic variables to illustrate the normative data. RESULTS A total of 125 participants, 65 men (52%) and 60 women (48%), met the inclusion criteria and completed the testing. Multiple regression and univariate analyses showed that although sex and age significantly affected cognitive performance on some CERAD-ArNB subtests, education level had by far the greatest effect. CONCLUSIONS Lower education level was associated with poorer CERAD-ArNB performance in a sample of cognitively normal Omanis aged 50 years and older. The normative data obtained from this study will help clinicians correctly interpret cognitive performance in the Omani elderly population, and probably in other, culturally similar Arabic-speaking communities.