Indigenous Australians experience higher levels of psychological distress compared to the general population. Physical activity is a culturally acceptable approach, associated with reduction of depressive symptoms. The protective properties of physical activity for depressive symptoms are yet to be evaluated in older Indigenous Australians.

A two-phase study design comprised of a qualitative thematic analysis following a quantitative regression and moderation analysis.

Firstly, a total of 336 Indigenous Australians aged 60 years and over from five NSW areas participated in assessments on mental health, physical activity participation, and childhood trauma. Secondly, a focus group of seven Indigenous Australians was conducted to evaluate barriers and facilitators to physical activity.

Regression and moderation analyses examined links between depression, childhood trauma, and physical activity. Thematic analysis was conducted exploring facilitators and barriers to physical activity following the focus group.

Childhood trauma severity and intensity of physical activity predicted depressive symptoms. Physical activity did not affect the strength of the relationship between childhood trauma and depression. Family support and low impact activities facilitated commitment to physical activity. In contrast, poor mental health, trauma, and illness acted as barriers.

Physical activity is an appropriate approach for reducing depressive symptoms and integral in maintaining health and quality of life. While situational factors, health problems and trauma impact physical activity, accessing low-impact group activities with social support was identified to help navigate these barriers.

Years of education is the most commonly used proxy measure of cognitive reserve. Other forms of cognitive stimulation in childhood may provide similar protection against cognitive decline, particularly in Indigenous groups, where education may have been lacking in quality or quantity. The Retrospective Indigenous Childhood Enrichment (RICE) scale was developed to measure non-school-based activities and environmental stimulation during childhood that are likely to have enhanced cognitive reserve. The aim of the study was to assess the validity and reliability of the RICE scale with a group of older Aboriginal Australians.

294 Aboriginal Australian people (60–92 years), living in urban or regional areas of NSW, completed the RICE scale as part of a longer face-to-face interview. Additional data was collected on their formal education, childhood environment, and childhood trauma (Study 1). Test–retest, inter-method and inter-rater reliability were assessed in a convenience sample of a further 38 participants by re-administration of the RICE scale at two time points, approximately 14 days apart (M = 14.11, SD = 6.78) (Study 2).

Factor analyses reduced the scale from 21 items to 18 and identified three factors: (1) Traditional, (2) Intellectual, and (3) Community. Higher scores on the RICE scale were related to higher years of formal education and lower scores on a childhood trauma questionnaire. The RICE scale had good internal consistency (Cronbach's α 0.79), and excellent test–retest reliability (ICC = 0.95, 95% CI 0.90–0.97) and inter-rater reliability (0.99, CI 95% 0.997–0.999).

The RICE is, to our knowledge, the first standardized measure that assesses the level of childhood environmental stimulation in older Aboriginal Australians. This could provide an important supplementary measure, in addition to formal education, to investigate cognitive reserve and dementia risk in this population and enhance understanding of the links between childhood experiences and late-life cognitive decline.