Cognitive screening and education: assessing the Montreal Cognitive Assessment’s validity in older Ugandan populations

Background: Cognitive screening tools such as the Montreal Cognitive Assessment (MoCA) are widely used to detect cognitive impairments. However, their accuracy in low- and middle-income countries (LMICs) may be affected by variations in educational levels. This study examined the impact of educational attainment on MoCA performance in older Ugandan adults, considering sex- and age-related differences. Methods: A cross-sectional study was conducted in Wakiso District, Uganda, involving adults aged ≥ 65 years. Their MoCA scores were analyzed in relation to their educational attainment, sex, and age. Multiple linear regression models were used to determine the independent effect of education on cognitive performance after adjusting for age and sex. Sensitivity analyses were conducted using multiple imputations for missing data. Results: Higher educational attainment was significantly associated with a better MoCA performance (β = 1.73, 95% CI: 1.22–2.24, p < 0.001). Age was negatively associated with MoCA scores (β = −0.13, 95% CI: −0.19 to −0.07, p < 0.001), whereas male sex was positively associated (β = 1.89, 95% CI: 0.56–3.22, p = 0.005). The interaction terms (education × sex and education × age) were not significant, indicating that the effect of education was consistent across demographic subgroups. The final regression model explained 42.7% of the variance in the MoCA scores (adjusted R2 = 0.43, p < 0.001). The sensitivity analysis confirmed the robustness of the findings. Conclusions: Educational attainment impacts MoCA performance in older Ugandans, highlighting the need for region-specific norms and culturally adapted cognitive screening in LMICs.