Kulay Kalingka, a national cohort study of Aboriginal and Torres Strait Islander peoples' cancer experiences: a study protocol.

INTRODUCTION: Aboriginal and Torres Strait Islander peoples are the First Peoples of Australia. Since settler colonisation, Aboriginal and Torres Strait Islander peoples have experienced disparities in health outcomes, including cancer, when compared with non-Indigenous Australians, including higher cancer incidence and mortality rates, and lower participation in cancer screening programmes. Data to monitor and improve outcomes are limited. AIMS, METHOD AND ANALYSIS: The Kulay Kalingka Study will be a national cohort study aiming to understand Aboriginal and Torres Strait Islander people's beliefs about cancer and experiences with cancer care and treatment, and to improve experiences and outcomes. It will be nested within the Mayi Kuwayu Study, a national community-controlled cohort study of Aboriginal and Torres Strait Islander people (n>11 000), with supplementary in-community recruitment.Mayi Kuwayu Study participants aged ≥18 years who consented to being recontacted, and a diversity of local community members will be invited to participate through completing a questionnaire relevant to their cancer status, aiming to recruit 2800 participants without prior doctor-diagnosed cancer and 700 with a cancer diagnosis.This community-driven data will enable monitoring and reporting of national trends over time and will guide national cancer control research, policy and clinical care, to improve outcomes for Aboriginal and Torres Strait Islander peoples. ETHICS AND DISSEMINATION: The Kulay Kalingka Study has ethics approval from Australian Institute of Aboriginal and Torres Strait Islander Studies (#EO324-20220414 and REC-0121) and the Australian National University (#2022/465). The Kulay Kalingka Study is being developed with Aboriginal and Torres Strait Islander communities, following the Maiam nayri Wingara Indigenous Data Sovereignty Collective principles. Meaningful, accessible and culturally adapted study findings will be disseminated to Aboriginal and Torres Strait Islander communities through activities including community workshops, reports and feedback sheets, and in other ways as determined by the community. We will also return data to participating communities.

Who responds? An examination of response rates to a national postal survey of Aboriginal and Torres Strait Islander adults, 2018-2019.

BACKGROUND: Evidence on the effectiveness of postal recruitment methods for Indigenous peoples is lacking. Mayi Kuwayu, the National Study of Aboriginal and Torres Strait Islander Wellbeing, uses multi-staged sampling. We aimed to test postal surveys as a primary recruitment method, analysing preliminary response rate data to inform the Study's ongoing sampling approach. METHODS: Twenty thousand adults aged ≥16 years were sampled from Aboriginal and Torres Strait Islander people enrolled in the Medicare Australia Enrolment Database. We calculated response rates at 4 and 15 weeks, overall and by age group, gender, state/territory and remoteness. RESULTS: The overall response rate was 2.3% (n = 456/20000). Highest response rates were observed among males and females ≥50 years from major cities (6.0, 95%CI 4.4-7.9 and 5.5%, 4.1-7.2, respectively) and regional areas (6.0%, 4.6-7.6 and 6.2%, 4.9-7.7, respectively). Younger age groups and remote areas had lower response rates; all remote age groups < 50 years had a response rate ≤ 0.6%. While most participants responded on the paper surveys, online responses were more common among younger age groups and, respondents with higher education levels and whose first language was not English. CONCLUSION: Using a postal survey, we observed response rates of ≥5.5% among older Aboriginal and Torres Strait Islander adults in major cities and regional areas; response rates were lower in other groups. A two-stage postal distribution approach provided an opportunity to adapt sampling approaches to different demographic groups. Based on initial response rates, the sampling strategy was revised to send postal surveys to groups with higher response rates groups and focus field recruitment strategies on low response groups.

'Telling our story... Creating our own history': caregivers' reasons for participating in an Australian longitudinal study of Indigenous children.

BACKGROUND: Improving the wellbeing of Indigenous populations is an international priority. Robust research conducted with Aboriginal and Torres Strait Islander peoples is key to developing programs and policies to improve health and wellbeing. This paper aims to quantify the extent of participation in a national longitudinal study of Aboriginal and Torres Strait Islander (Indigenous Australian) children, and to understand the reasons why caregivers participate in the study. METHODS: This mixed methods study uses data from Wave 6 of Footprints in Time, the Longitudinal Study of Indigenous Children. We conducted descriptive analysis of quantitative variables to characterise the sample and retention rates. We applied conventional content analysis to 160 caregivers' open-ended responses to the question, 'Why do you stay in the study?', identifying themes and overarching meta-themes. RESULTS: The study has maintained a high retention rate, with 70.4% (n = 1239/1671) of the baseline sample participating in the study's 6th wave. We identified seven themes related to why participants stay in the study: telling our story, community benefit, satisfaction, tracking Study Child's progress, study processes, receiving study gifts, and valuing what the study stands for. These related to two meta-themes: reciprocity, and trust and connection. Caregivers reported that participation was associated with benefits for their family and community as well as for the study. They identified specific features of the Footprints in Time study design that built and maintained trust and connection between participants and the study. CONCLUSIONS: Our findings support the assertion that Aboriginal and Torres Strait Islander people want to be involved in research when it is done 'the right way'. Footprints in Time has successfully recruited and retained the current-largest cohort of Aboriginal and Torres Strait Islander children in Australia through the use of participatory research methodologies, suggesting effective study implementation and processes. Participants indicated ongoing commitment to the study resulting from perceptions of reciprocity and development of trust in the study. Footprints in Time can serve as a successful model of Aboriginal and Torres Strait Islander health research, to promote good research practice and provides lessons for research with other Indigenous populations.

Obesity and its association with sociodemographic factors, health behaviours and health status among Aboriginal and non-Aboriginal adults in New South Wales, Australia.

BACKGROUND: High body mass index (BMI) is the second leading contributor to Australia's burden of disease and is particularly prevalent among Aboriginal peoples. This paper aims to provide insight into factors relating to obesity among Aboriginal adults and Aboriginal-non-Aboriginal differences. METHODS: Cross-sectional analysis of data from the 45 and Up Study, comparing obesity (BMI ≥30 kg/m2) prevalence and risk factors among 1515 Aboriginal and 213 301 non-Aboriginal adults in New South Wales. Age-sex-adjusted prevalence ratios (PRs) for obesity by sociodemographic factors, health behaviours and health status were estimated (multivariable log-binomial regression) for Aboriginal and non-Aboriginal participants separately. We quantified the extent to which key factors (physical activity, screen time, education, remoteness, area-level disadvantage) accounted for any excess Aboriginal obesity prevalence. RESULTS: Obesity prevalence was 39% among Aboriginal and 22% among non-Aboriginal participants (PR=1.65, 95% CI 1.55 to 1.76). Risk factors for obesity were generally similar for Aboriginal and non-Aboriginal participants and included individual-level and area-level disadvantage, physical inactivity, and poor physical and mental health, with steeper gradients observed among non-Aboriginal participants for some factors (Pinteraction <0.05). Many risk factors were more common among Aboriginal versus non-Aboriginal participants; key factors accounted for >40% of the excess Aboriginal obesity prevalence. CONCLUSION: A substantial proportion of the excess obesity prevalence among Aboriginal versus non-Aboriginal participants was explained by physical activity, screen time, education, remoteness and area-level disadvantage. Socioeconomic and health behaviour factors are potential targets for promoting healthy BMI, but these must be considered within the context of upstream social and cultural factors. Adults with health needs and disability require particular attention.

Body mass index trajectories of Indigenous Australian children and relation to screen time, diet, and demographic factors.

OBJECTIVE: Limited cross-sectional data indicate elevated overweight/obesity prevalence among Indigenous versus non-Indigenous Australian children. This study aims to quantify body mass index (BMI) trajectories among Indigenous Australian children aged 3-6 and 6-9 years and to identify factors associated with the development of overweight/obesity. METHODS: Three-year BMI change was examined in up to 1,157 children in the national Longitudinal Study of Indigenous Children. BMI trajectories among children with normal baseline BMI (n = 907/1,157) were quantified using growth curve models. RESULTS: Baseline prevalences of overweight/obesity were 12.1% and 25.4% among children of mean age 3 and 6 years, respectively. Of children with normal baseline BMI, 31.9% had overweight/obesity 3 years later; BMI increased more rapidly for younger versus older (difference: 0.59 kg/m2 /year; 95% CI: 0.50-0.69), female versus male (difference: 0.15 kg/m2 /year; 95% CI: 0.07-0.23), and Torres Strait Islander versus Aboriginal (difference: 0.36 kg/m2 /year; 95% CI: 0.17-0.55) children. Results were consistent with less rapid rates of BMI increase for children with lower sugar-sweetened beverage (including fruit juice) and high-fat food consumption. Children's BMI was lower in more disadvantaged areas. CONCLUSIONS: Overweight/obesity is common, and increases rapidly, in early childhood. Interventions are required to reduce the overweight/obesity prevalence among Indigenous Australian children in the first 3 years of life and to slow the rapid overweight/obesity onset from age 3 to 9 years.

Understanding barriers to fruit and vegetable intake in the Australian Longitudinal Study of Indigenous Children: a mixed-methods approach.

OBJECTIVE: To identify barriers to fruit and vegetable intake for Indigenous Australian children and quantify factors related to these barriers, to help understand why children do not meet recommendations for fruit and vegetable intake. DESIGN: We examined factors related to carer-reported barriers using multilevel Poisson models (robust variance); a key informant focus group guided our interpretation of findings. SETTING: Eleven diverse sites across Australia. SUBJECTS: Australian Indigenous children and their carers (N 1230) participating in the Longitudinal Study of Indigenous Children. RESULTS: Almost half (45 %; n 555/1230) of carers reported barriers to their children's fruit and vegetable intake. Dislike of fruit and vegetables was the most common barrier, reported by 32·9 % of carers; however, we identified few factors associated with dislike. Carers were more than ten times less likely to report barriers to accessing fruit and vegetables if they lived large cities v. very remote areas. Within urban and inner regional areas, child and carer well-being, financial security, suitable housing and community cohesion promoted access to fruit and vegetables. CONCLUSIONS: In this national Indigenous Australian sample, almost half of carers faced barriers to providing their children with a healthy diet. Both remote/outer regional carers and disadvantaged urban/inner regional carers faced problems accessing fruit and vegetables for their children. Where vegetables were accessible, children's dislike was a substantial barrier. Nutrition promotion must address the broader family, community, environmental and cultural contexts that impact nutrition, and should draw on the strengths of Indigenous families and communities.