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Objective The prevalence of dementia and cognitive impairment is higher in Aboriginal Australians compared to the national population, increasing the need to understand cognitive impairment in this at‐risk population. This article reports normative data for a range of commonly used cognitive tests, in a population‐based small normative sample of older Aboriginal Australians living in urban/regional New South Wales. Method Participants included a representative random sample of community‐dwelling older adults (60-years and older) with no cognitive impairment (n = 31), mild cognitive impairment (MCI; n = 38), or dementia diagnosis (n = 35), all from the Koori Growing Old Well Study. Cognitive tests included the Addenbrooke's Cognitive Examination Revised (ACE‐R), Digit Span (Forward and Backward), Logical Memory, and the Oral Trail Making Test (A and B). Results Descriptive statistics and percentile scores for each test were reported for the normative sample. Comparison of performance between the diagnostic groups showed significant differences between the groups on most cognitive tests. The control group consistently performed better than the dementia group; and better than the MCI group on all tests, except for simple attention and sequencing tasks (Digit Span Forward and Oral Trail Making A). The MCI group also scored better than the dementia group on all tests, except for the Logical Memory Recognition task. Conclusion Results support the utility of these cognitive tests that are commonly used in clinical and research settings, and demonstrate that these tests can discriminate between diagnostic groups in Aboriginal Australians. The normative data provided will enhance cognitive assessment of individuals within this population.

Abstract Introduction Aboriginal Australians have among the highest rates of dementia worldwide, yet no study has investigated the subtypes, risk factors, or longer term outcomes of mild cognitive impairment (MCI) in this population. Methods A total of 336 community‐dwelling Aboriginal Australians aged ≥60 years participated in a longitudinal study, completing a structured interview at baseline. MCI (amnestic subtype, aMCI; non‐amnestic subtype, naMCI) and dementia were diagnosed via cognitive screening, medical assessment, and clinical consensus. Associations between life‐course factors and baseline MCI subtypes were examined using logistic regression. Conversion to dementia was assessed at 6‐year follow‐up. Results Prevalent aMCI (n = 24) was associated with older age (odds ratio [OR] = 1.68, 95% confidence interval [CI]: 1.12 to 2.53), head injury (OR = 3.19, 95% CI: 1.35 to 7.56), symptoms of depression (OR = 1.52, 95% CI: 1.04 to 2.24), and lower blood pressure (OR = 0.53, 95% CI: 0.33 to 0.86). Prevalent naMCI (n = 29) was associated with low education (OR = 4.46, 95% CI: 1.53 to 13.05), unskilled work history (OR = 5.62, 95% CI: 2.07 to 13.90), higher body mass index (OR = 1.99, 95% CI: 1.30 to 3.04), and moderate to severe hearing loss (OR = 2.82, 95% CI: 1.06 to 7.55). A small proportion of MCI cases reverted to intact at follow‐up (15%), but most remained stable (44%), developed dementia and/or died (41%). Discussion Sociodemographic and clinical factors both contributed to baseline MCI and were distinct for MCI subtypes, with similar patterns of conversion to dementia for amnestic and non‐amnestic MCI.