Aims: To develop a primary care rapid dementia screen through psychometric analysis of the 16-item Kimberley Indigenous Cognitive Assessment (KICA-Cog), a valid cognitive tool for Aboriginal and Torres Strait Islander peoples.
Methods: We harmonised three cohort studies with KICA-Cog assessments of Aboriginal and Torres Strait Islander peoples aged ≥45 years. Logistic regression was used to evaluate the cross-sectional association between individual items of the KICA-Cog and presence of dementia and/or cognitive impairment not dementia (CIND) by independent consensus diagnoses, to identify candidate items for a rapid scale. Sensitivity, specificity and optimal cut-off scores were calculated through receiver operating characteristic (ROC) curve analysis. The resulting short scales were then validated in a separate cohort of Aboriginal and Torres Strait Islander peoples.
Results: 113 (13%) of 898 participants (mean age 64.4 [SD 9.8] years, 60% female) had a consensus clinical diagnosis of dementia. A combination of four items in the KICA-Cog (orientation to time, orientation to place, verbal fluency, and picture naming recall) demonstrated high sensitivity (82.6%), specificity (83.2%), and AUC of 0.90 (95% CI 0.87-0.94) for dementia. Validation of this prototype scale in a separate cohort of 84 individuals yielded good sensitivity (87.5%), specificity (80.9%), and discriminatory value for dementia (AUC of 0.92 95% CI 0.85-0.98) at the cut-off point of 7/8 out of 10.
Conclusions: The developed 4-item prototype scale based on the KICA-Cog is ready for community piloting and validation and may be useful in primary care for rapid cognitive screening as part of routine health care.