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Methods for calculating health indicators profoundly influence understanding of and action on population health and inequities. Age-standardization can be useful and is commonly applied to account for differences in age structures when comparing health indicators across groups. Age-standardized rates have well-acknowledged limitations, including that they are relative indices for comparison, and not accurate measures of actual rates where the age structures of groups diverge. This paper explores these limitations, and demonstrates alternative approaches through a case study quantifying mortality rates within the Aboriginal and Torres Strait Islander (Indigenous) population of Australia and inequities compared with the non-Indigenous population, over 2001-16. Applying the Australian Standard Population, the Aboriginal and Torres Strait Islander age-standardized mortality rate was more than double the crude mortality rate in 2001 and 2016, inflated through high weighting of older age groups. Despite divergent population age structures, age-standardized mortality rates remain a key policy metric for measuring progress in reducing Indigenous-non-Indigenous inequities in Australia. Focusing on outcomes age-standardized to the total population can obscure inequities, and denies Aboriginal and Torres Strait Islander peoples and communities valid, actionable information about their health and well-being. Age-specific statistics convey the true magnitude of health risks and highlight high-risk subgroups. When requiring standardization, standardizing to a population-specific standard (here, an Indigenous standard) generates metrics centred around and reflective of reality for the population of focus, supporting communities' self-determination to identify priorities and informing resource allocation and service delivery. The principles outlined here apply across populations, including Indigenous and other populations internationally. [ABSTRACT FROM AUTHOR]

Background The positive cross-sectional association between health and SES often strengthens at younger ages before peaking at middle ages and then weakening at older ages. Selective mortality is a possible reason for the weakening relationship at older ages but current evidence for this is limited. Methods This paper uncovers the changing nature of the inter-dependence between SES and health over the lifecycle by further developing and applying longitudinal inequality decomposition techniques which account for mortality. We examine changes in SES-related health inequality for rolling age cohorts by gender for Australia (using the Household, Income and Labour Dynamics in Australia (HILDA) survey) and the United Kingdom (using the Understanding Society survey). Results We find for young men in both countries that the simultaneous co-movement in both health and income plays the major role in increasing health inequalities. At middle ages the poor start to lose health more quickly than the rich but at older ages selective mortality plays the major role with the poor more likely to die than the rich which also has an indirect effect of making morbidity losses seem less concentrated among the poor. Conclusions Selective mortality plays a major role in weakening the relationship between SES and health at older ages. Past studies have missed identifying the full effect of selective mortality. Key messages SES-related health inequalities accumulate throughout the lifecycle, even in older ages. [ABSTRACT FROM AUTHOR]

Focus of Presentation Rheumatic fever (RF) and rheumatic heart disease (RHD) are endemic among Indigenous Australians. End RHD in Australia: Study of Epidemiology (ERASE) aimed to characterize contemporary RF/RHD epidemiology. Using multi-jurisdictional linked data from several administrative sources, we undertook sub-studies covering diverse epidemiological questions, requiring substantial methods development. Mixed methods further identified barriers/facilitators to inform system redesign. Our multi-disciplinary collaboration supported diverse initiatives to contribute to policy at government, service and community/stakeholder levels. We show how findings from ERASE were applied/translated to address the impact of RF/RHD in Australia. Findings Academic: >15 papers and commentaries/editorials provided the backbone to translational outputs and methods sharing. PhD students have ongoing projects using ERASE datasets. Advocacy: ERASE epidemiological and economic information supported the Endgame Strategy (roadmap for eliminating RHD in Australia by 2031) presented to government. Health professionals: ERASE data contributed to Australian RF/RHD guidelines. Slides of results/interpretation are publically-available on the RHDAustralia website. Student lectures integrate biomedical and culturally-informed perspectives. Indigenous stakeholder engagement: involves (1)presentations to peak Indigenous-controlled organisations (2)co-designed resources (booklets/slides) for capacity-building of RHDAustralia's national Champions4Change network (3)research workshops to promote two-way learning and health literacy/numeracy. Challenges remain regarding strengths-based approaches when reporting high disparities. Conclusions/Implications Strong translational commitment and national multi-disciplinary networks of Indigenous and non-Indigenous collaborators ensured ERASE generated multiple outputs that continue to inform training, practice, policy and community health literacy. Key messages Build translation and broad collaboration into study from the start. [ABSTRACT FROM AUTHOR]

Background: Suicide is higher among economically inactive and unemployed persons than employed persons. This paper investigates differences in this relationship by sex and age over the period 2001 to 2010 in Australia. It also examines changes in suicide among employed, unemployed and economically inactive persons during the recession of 2007–09.Method: Suicide data from the National Coroners Information System were utilised for this retrospective study. Negative binomial and Poisson regression was used to estimate the association between suicide and employment status and to investigate differences in suicide rates over the period of the recession (2007–09) compared with the year before the recession (2006).Results: Results suggest that during 2001–10 economically inactive/unemployed males had a suicide rate ratio (RR) of 4.62 [95% confidence interval (CI) 4.10, 5.19; P < 0.001] compared with employed males (RR = 1.00), whereas economically inactive/unemployed females had a suicide RR of 8.44 compared with employed females (95% CI 7.38, 9.67; P < 0.001). There was an increase in suicide among both employed (7% rise in 2007, P = 0.003) and economically inactive/unemployed males during the GFC (22% in 2008, P < 0.001). Suicide also increased among economically inactive/unemployed females (12% in 2007, P = 0.03; 19% in 2008, P = 0.001) but not among employed females.Conclusions: These results suggest the need for adequate policy and social welfare responses to ameliorate the effects of the economic recession on the working age population. Particularly, these should target unemployed and economically inactive men and women in Australia, who may be at higher risk of suicide than previously thought. [ABSTRACT FROM AUTHOR]

Background: Understanding the relationship between different aspects of disadvantage over time and domains of child development will facilitate the formulation of more precise policy responses. We examined the association between exposure to aspects of disadvantage over the childhood period (from 0-9 years) and child development at 10-11 years.Methods: We used data from the nationally representative birth cohort of the Longitudinal Study of Australian Children (n = 4979). Generalized linear models with log-Poisson link were used to estimate the association between previously derived disadvantage trajectories (in each of four lenses of sociodemographic, geographic environments, health conditions and risk factors, and a composite of these) and risk of poor child developmental outcomes. Population-attributable fractions were calculated to quantify the potential benefit of providing all children with optimal conditions for each developmental outcome.Results: Trajectories of disadvantage were associated with developmental outcomes: children in the most disadvantaged composite trajectory had seven times higher risk of poor outcomes on two or more developmental domains, compared with those most advantaged. Trajectories of disadvantage in different lenses were varyingly associated with the child development domains of socio-emotional adjustment, physical functioning and learning competencies. Exposure to the most advantaged trajectory across all lenses could reduce poor developmental outcomes by as much as 70%.Conclusions: Exposure to disadvantage over time is associated with adverse child development outcomes. Developmental outcomes varied with the aspects of disadvantage experienced, highlighting potential targets for more precise policy responses. The findings provide evidence to stimulate advocacy and action to reduce child inequities. [ABSTRACT FROM AUTHOR]

Background Long COVID symptoms occur for a proportion of acute COVID-19 survivors, with reduced risk among the vaccinated and for Omicron compared with Delta variant infections. The health loss attributed to pre-Omicron long COVID has previously been estimated using only a few major symptoms. Methods The years lived with disability (YLDs) due to long COVID in Australia during the 2021–22 Omicron BA.1/BA.2 wave were calculated using inputs from previously published case-control, cross-sectional or cohort studies examining the prevalence and duration of individual long COVID symptoms. This estimated health loss was compared with acute SARS-CoV-2 infection YLDs and years of life lost (YLLs) from SARS-CoV-2. The sum of these three components equals COVID-19 disability-adjusted life years (DALYs); this was compared with DALYs from other diseases. Results A total of 5200 [95% uncertainty interval (UI) 2200 – 8300] YLDs were attributable to long COVID and 1800 (95% UI 1100-2600) to acute SARS-CoV-2 infection, suggesting long COVID caused 74% of the overall YLDs from SARS-CoV-2 infections in the BA.1/BA.2 wave. Total DALYs attributable to SARS-CoV-2 were 50 900 (95% UI 21 000-80 900), 2.4% of expected DALYs for all diseases in the same period. Conclusion This study provides a comprehensive approach to estimating the morbidity due to long COVID. Improved data on long COVID symptoms will improve the accuracy of these estimates. As data accumulate on SARS-CoV-2 infection sequelae (e.g. increased cardiovascular disease rates), total health loss is likely to be higher than estimated in this study. Nevertheless, this study demonstrates that long COVID requires consideration in pandemic policy planning, given it is responsible for the majority of direct SARS-CoV-2 morbidity, including during an Omicron wave in a highly vaccinated population. [ABSTRACT FROM AUTHOR]

Background With high temperature becoming an increasing health risk due to a changing climate, it is important to quantify the scale of the problem. However, estimating the burden of disease (BoD) attributable to high temperature can be challenging due to differences in risk patterns across geographical regions and data accessibility issues. Methods We present a methodological framework that uses Köppen–Geiger climate zones to refine exposure levels and quantifies the difference between the burden observed due to high temperatures and what would have been observed if the population had been exposed to the theoretical minimum risk exposure distribution (TMRED). Our proposed method aligned with the Australian Burden of Disease Study and included two parts: (i) estimation of the population attributable fractions (PAF); and then (ii) estimation of the BoD attributable to high temperature. We use suicide and self-inflicted injuries in Australia as an example, with most frequent temperatures (MFTs) as the minimum risk exposure threshold (TMRED). Results Our proposed framework to estimate the attributable BoD accounts for the importance of geographical variations of risk estimates between climate zones, and can be modified and adapted to other diseases and contexts that may be affected by high temperatures. Conclusions As the heat-related BoD may continue to increase in the future, this method is useful in estimating burdens across climate zones. This work may have important implications for preventive health measures, by enhancing the reproducibility and transparency of BoD research. [ABSTRACT FROM AUTHOR]

Background: Estimates of burden of disease are important for monitoring population health, informing policy and service planning. Burden estimates for the same population can be reported differently by national studies [e.g. the Australian Burden of Disease Study (ABDS) and the Global Burden of Disease Study (GBDS)].Methods: Australian ABDS 2015 and GBDS 2017 burden estimates and methods for 2015 were compared. Years of life lost (YLL), years lived with disability (YLD) and disability-adjusted life years (DALY) measures were compared for overall burden and 'top 50' causes. Disease-category definitions (based on ICD-10), redistribution algorithms, data sources, disability weights, modelling methods and assumptions were reviewed.Results: GBDS 2017 estimated higher totals than ABDS 2015 for YLL, YLD and DALY for Australia. YLL differences were mainly driven by differences in the allocation of deaths to disease categories and the redistribution of implausible causes of death. For YLD, the main drivers were data sources, severity distributions and modelling strategies. Most top-50 diseases for DALY had a similar YLL:YLD composition reported.Conclusions: Differences in the ABDS and GBDS estimates reflect the different purposes of local and international studies and differences in data and modelling strategies. The GBDS uses all available evidence and is useful for international comparisons. National studies such as the ABDS have the flexibility to meet local needs and often the advantage of access to unpublished data. It is important that all data sources, inputs and models be assessed for quality and appropriateness. As studies evolve, differences should be accounted for through increased transparency of data and methods. [ABSTRACT FROM AUTHOR]

Background: Little is known about the long-term health impacts of exposures to landscape fire smoke. We aimed to evaluate the association between exposure to coal mine fire-related particulate matter 2.5 μm or less in diameter (PM2.5) and hospitalisation in the 5 years following the 6-week Hazelwood coal mine fire in Australia in 2014.Methods: We surveyed 2725 residents (mean age: 58.3 years; 54.3% female) from an exposed and a comparison town. Individual PM2.5 exposures during the event were estimated using modelled PM2.5 concentrations related to the coal mine fire and self-reported location data. The individual exposure and survey data were linked with hospitalisation records between January 2009 and February 2019. Recurrent event survival analysis was used to evaluate relationships between PM2.5 exposure and hospitalisation following mine fire, adjusting for important covariates.Results: Each 10-µg/m3 increase in mine fire-related PM2.5 was associated with a 9% increased hazard [hazard ratio (HR) = 1.09; 95% confidence interval (CI): 1.01, 1.17] of respiratory hospitalisation over the next 5 years, with stronger associations observed for females (HR = 1.16; 95% CI: 1.06, 1.27) than males (HR = 0.99; 95% CI: 0.89, 1.11). In particular, increased hazards were observed for hospitalisations for asthma (HR = 1.43; 95% CI: 1.19, 1.73) and chronic obstructive pulmonary disease (HR = 1.14; 95% CI: 1.02, 1.28). No such association was found for hospitalisations for cardiovascular diseases, mental illness, injuries, type 2 diabetes, renal diseases or neoplasms.Conclusions: A 6-week exposure to coal mine fire-related PM2.5 was associated with increased hazard of respiratory hospitalisations over the following 5 years, particularly for females. [ABSTRACT FROM AUTHOR]

Background: Socioeconomic inequalities in mortality are evident in all high-income countries, and ongoing monitoring is recommended using linked census-mortality data. Using such data, we provide the first estimates of education-related inequalities in cause-specific mortality in Australia, suitable for international comparisons.Methods: We used Australian Census (2016) linked to 13 months of Death Registrations (2016-17). We estimated relative rates (RR) and rate differences (RD, per 100 000 person-years), comparing rates in low (no qualifications) and intermediate (secondary school) with high (tertiary) education for individual causes of death (among those aged 25-84 years) and grouped according to preventability (25-74 years), separately by sex and age group, adjusting for age, using negative binomial regression.Results: Among 13.9 M people contributing 14 452 732 person-years, 84 743 deaths occurred. All-cause mortality rates among men and women aged 25-84 years with low education were 2.76 [95% confidence interval (CI): 2.61-2.91] and 2.13 (2.01-2.26) times the rates of those with high education, respectively. We observed inequalities in most causes of death in each age-sex group. Among men aged 25-44 years, relative and absolute inequalities were largest for injuries, e.g. transport accidents [RR = 10.1 (5.4-18.7), RD = 21.2 (14.5-27.9)]). Among those aged 45-64 years, inequalities were greatest for chronic diseases, e.g. lung cancer [men RR = 6.6 (4.9-8.9), RD = 57.7 (49.7-65.8)] and ischaemic heart disease [women RR = 5.8 (3.7-9.1), RD = 20.2 (15.8-24.6)], with similar patterns for people aged 65-84 years. When grouped according to preventability, inequalities were large for causes amenable to behaviour change and medical intervention for all ages and causes amenable to injury prevention among young men.Conclusions: Australian education-related inequalities in mortality are substantial, generally higher than international estimates, and related to preventability. Findings highlight opportunities to reduce them and the potential to improve the health of the population. [ABSTRACT FROM AUTHOR]

Background: Many studies have reported an inferred causal association of income poverty with physical health among children; but making causal inference is challenging due to multiple potential sources of systematic error. We quantified the short-run effect of changes in household poverty status on children's health (asthma and ear infections) and service use (visits to the doctor and parent-reported hospital admissions), using a national longitudinal study of Australian children, with particular attention to potential residual confounding and selection bias due to study attrition.Methods: We use four modelling approaches differing in their capacity to reduce residual confounding (generalized linear, random effects (RE), hybrid and fixed effects (FE) regression modelling) to model the effect of income poverty (<60% of median income) on health for 10 090 children surveyed every 2nd year since 2004. For each method, we simulate the potential impact of selection bias arising due to attrition related to children's health status.Results: Of the 10 090 children included, 20% were in families in poverty at survey baseline (2004). Across subsequent years, ∼25% experienced intermittent and <2% persistent poverty. No substantial associations between poverty and child physical health and service use were observed in the FE models least prone to residual confounding [odds ratio (OR) 0.94, 95% confidence interval (CI) 0.81-1.10 for wheeze], in contrast to RE models that were positive (consistent with previous studies). Selection bias causing null findings was unlikely.Conclusions: While poverty has deleterious causal effects on children's socio-behavioural and educational outcomes, we find little evidence of a short-run causal effect of poverty on asthma, ear infections and health service use in Australia. [ABSTRACT FROM AUTHOR]

Background: Despite generally high smoking prevalences, stemming from colonization, the relationship of smoking to mortality has not been quantified reliably in an Indigenous population. We investigate smoking and mortality among Aboriginal and Torres Strait Islander adults in Australia, where current adult daily smoking prevalence is 40.2%.Methods: A prospective study of 1388 cardiovascular disease- and cancer-free Aboriginal adults aged ≥45 years, of the 267 153 45 and Up Study participants randomly sampled from the New South Wales general population over 2006-09. Questionnaire and mortality data were linked (through the Centre for Health Record Linkage) to mid-2019. Adjusted hazard ratios (called relative risks, RRs) for all-cause mortality-among current- and past- versus never-smokers-were estimated overall, by smoking intensity and by age at cessation. Smoking-attributable fractions and associated deaths were estimated.Results: Over 14 586 person-years' follow-up (median 10.6 years), 162 deaths accrued. Mortality RRs [95% confidence interval (CI)] were 3.90 (2.52-6.04) for current- and 1.95 (1.32-2.90) for past- versus never-smokers, with age heterogeneity. RRs increased with smoking intensity, to 4.29 (2.15-8.57) in current-smokers of ≥25 cigarettes/day. Compared with never-smokers, RRs were 1.48 (0.85-2.57) for those quitting at <45 years of age and 2.21 (1.29-3.80) at 45-54 years. Never-smokers lived an average >10 years longer than current-smokers. Around half of deaths among adults aged ≥45 years were attributable to smoking, exceeding 10 000 deaths in the past decade.Conclusions: In this population, >80% of never-smokers would survive to 75 years, versus ∼40% of current-smokers. Quitting at all ages examined had substantial benefits versus continuing smoking; those quitting before age 45 years had mortality risks similar to never-smokers. Smoking causes half of deaths in older Aboriginal and Torres Strait Islander adults; Indigenous tobacco control must receive increased priority. [ABSTRACT FROM AUTHOR]

Background: The recent slowdown in life expectancy increase in Australia has occurred concurrently with widening socioeconomic and geographical inequalities in all-cause mortality risk. We analysed whether, and to what extent, mortality inequalities among specific non-communicable diseases (NCDs) in Australia at ages 35-74 years widened during 2006-16.Methods: Registered deaths that occurred during 2006-16 in Australia were analysed. Inequalities were measured by area socioeconomic quintile [ranging from Q1 (lowest) to Q5 (highest)] and remoteness (major cities, inner regional, outer regional/remote/very remote). Age-standardized death rates (ASDR) for 35-74 years were calculated and smoothed over time.Results: NCD mortality inequalities by area socioeconomic quintile widened; the ratio of Q1 to Q5 ASDR for males increased from 1.96 [95% confidence interval (CI) 1.91-2.01] in 2011 to 2.08 (2.03-2.13) in 2016, and for females from 1.78 (1.73-1.84) to 1.96 (1.90-2.02). Moreover, Q1 NCD ASDRs did not clearly decline from 2011 to 2016. CVD mortality inequalities were wider than for all NCDs. There were particularly large increases in smoking-related mortality inequalities. In 2016, mortality inequalities were especially high for chronic respiratory diseases, alcohol-related causes and diabetes. NCD mortality rates outside major cities were higher than within major cities, and these differences widened during 2006-16. Higher mortality rates in inner regional areas than in major cities were explained by socioeconomic factors.Conclusions: Widening of inequalities in premature mortality rates is a major public health issue in Australia in the context of slowing mortality decline. Inequalities are partly explained by major risk factors for CVDs and NCDs: being overweight or obese, lack of exercise, poor diet and smoking. There is a need for urgent policy responses that consider socioeconomic disadvantage. [ABSTRACT FROM AUTHOR]

Background: Serum 25 hydroxyvitamin D [25(OH)D] levels of pregnant women have been linked to various health outcomes in their offspring. Satellite-derived ultraviolet radiation (UVR) data have been used as a proxy for 25(OH)D levels, as individual-level cohort studies are time-consuming, costly and only feasible for common outcomes.Methods: Data on 25(OH)D levels from a public laboratory database were linked to data from the Western Australian Midwives' Notification System and daily erythemal UVR dose from NASA satellites. Regression analysis was used to identify the time period prior to venesection where daily UVR dose best predicted 25(OH)D levels. A predictive model was used to validate the use of daily UVR dose as a proxy for personal sun exposure during pregnancy.Results: Data from 19 173 pregnancies in women aged 18-43 years in Western Australia were included. The daily UVR dose averaged over the 90 days before venesection was the strongest UVR predictor of 25(OH)D level (a 5% increase per 1000 J m-2; equal to 3.3 nmol L-1 at the median of 66 nmol L-1). Ethnicity was the strongest predictor of 25(OH)D levels (21% lower in non-Caucasian vs Caucasian: equal to 7.2 nmol L-1 difference). Other significant predictors were gestation, age, year, parity, socio-economic status, remoteness, medical conditions and season.Conclusion: NASA-derived erythemal UVR dose in the 90 days prior to venesection is a significant predictor of 25(OH)D levels in pregnant women. Linked administrative data can be used to investigate associations between UVR during pregnancy and health outcomes in offspring. [ABSTRACT FROM AUTHOR]

Background: A farm upbringing has been associated with lower risk of asthma and methylation of asthma-related genes. As such, a farm upbringing has the potential to transfer asthma risk across generations, but this has never been investigated. We aimed to study the generational effects from a parental farm upbringing on offspring asthma.Methods: Our study involved three generations: 5759 participants from the European Community Respiratory Health Survey (ECRHS) study (born 1945-1971, denoted G1), their 9991 parents (G0) and their 8260 offspring (G2) participating in RHINESSA (Respiratory Health In Northern Europe, Spain and Australia). Questionnaire data were collected on G0 and G1 from G1 in 2010 and on G2 from themselves in 2013. The parental/grandparental place of upbringing was categorized: (i) both parents from farm; (ii) mother from farm, father from village/city; (iii) father from farm, mother from village/city; (iv) both parents from village or one parent from village and one from city; (v) both parents from city (reference group). Grandparental upbringing was equivalently categorized. Offspring asthma was self-reported and data were analysed using Cox-regression models with G2 age as the time scale.Results: A parental farm upbringing was not associated with offspring asthma when compared with city upbringing [hazard ratio (HR) 1.12, 95% confidence interval (CI) 0.74-1.69]. Findings remained similar when stratified by offspring upbringing and asthma phenotypes. Quantitative bias analyses showed similar estimates for alternative data sources. A grandparental farm upbringing was not associated with offspring asthma in either the maternal (HR 1.05, 95% CI 0.67-1.65) or paternal line (HR 1.02, 95% CI 0.62-1.68).Conclusions: This multigenerational analysis suggests no evidence of an association between parental/grandparental farm upbringing and offspring asthma. [ABSTRACT FROM AUTHOR]

Background: Cross-sectional studies suggest that more green space may lower the odds of prevalent diabetes, hypertension and cardiovascular diseases (CVD) in cities. We assess if these results are replicable for tree canopy exposure and then extend the study longitudinally to examine incident cardiometabolic outcomes.Methods: The study was set in the Australian cities of Sydney, Wollongong and Newcastle. Total green space and tree canopy as percentages of landcover within 1.6 km (1 mile) from home were linked to a residentially stable sample of 46 786 participants in the Sax Institute's 45 and Up Study (baseline 2006-09; follow-up 2012-15). Separate multilevel models were used to investigate whether the odds of prevalent and incident doctor-diagnosed diabetes, hypertension and CVD were associated with total green space and tree canopy provision, adjusting for age, sex, income, education, employment and couple status.Results: Lower odds of prevalent diabetes were observed with 1% increases in total green space [odds ratio (OR) 0.993, 95% confidence interval (CI) 0.988 to 0.998] and tree canopy (0.984, 0.978 to 0.989). Lower odds of prevalent CVD were found with a 1% increase in tree canopy only (0.996, 0.993 to 0.999). Lower odds of incident diabetes (0.988, 0.981 to 0.994), hypertension (0.993, 0.989 to 0.997) and CVD (0.993, 0.988 to 0.998) were associated with a 1% increase in tree canopy, but not total green space. At ≥30% compared with 0-9% tree canopy, there were lower odds of incident diabetes (0.687, 0.547 to 0.855), hypertension (0.828, 0.719 to 0.952) and CVD (0.782, 0.652 to 0.935). However, ≥30% compared with 0-4% total green space was associated with lower odds of prevalent diabetes only (0.695, 0.512 to 0.962).Conclusions: Restoring local tree canopy in neighbourhoods may help to prevent the incidence of cardiometabolic diseases. [ABSTRACT FROM AUTHOR]

Background: The ways children spend their time is one of the most valuable inputs for healthy child development. It is unknown which time investment yields the greatest return for children's language and behavioural outcomes at school entry.Methods: We used data from the first three waves (2004, 2006, 2008) of the Longitudinal Study of Australian Children (n = 4253). At every wave, parents completed 24-h time-use diaries on one randomly selected week and one weekend day. The amount of time children spent on 11 activities at ages 0-1, 2-3 and 4-5 years was analysed. Receptive vocabulary was assessed using the Peabody Picture Vocabulary Test, and externalizing behaviours were measured by the Strengths and Difficulties Questionnaire, completed by parents and teachers at 4-5 years. To identify which time investment in the first 5 years of life mattered most for children's outcomes, a new production function was developed. This production function was estimated using a log-log linear regression model.Results: Relative to other time investments, time spent on educational activities at 2-3 years of age was the most important time investment for receptive vocabulary and behavioural outcomes at school entry. After adjusting for confounding, every 1 h invested in educational activities at 2-3 years was associated with a 0.95% [95% CI (confidence interval): 0.62, 1.28] increase in receptive vocabulary, and a -5.72% (95% CI: -7.71, -3.73) and -9.23% (95% CI: -12.26, -6.20) reduction in parent- and teacher-reported externalizing problem behaviours. Time invested in play was also important to both receptive vocabulary and behaviour. One hour invested in play at 2-3 and 4-5 years was associated with a 0.68% (95% CI: 0.38, 0.98) and 0.71% (95% CI: 0.39, 1.03) increase in children's receptive vocabulary at school entry. In addition, time invested in play at 2-3 and 4-5 years was associated with reduced problem behaviours at school entry. In contrast, screen time at all ages was associated with poorer parent- and teacher-reported externalizing problem behaviours.Conclusions: These results suggest that time invested in educational activities at 2-3 years of age yield the greatest return for children's receptive vocabulary and behaviour at school entry. [ABSTRACT FROM AUTHOR]

Background: National linked mortality and census data have not previously been available for Australia. We estimated education-based mortality inequalities from linked census and mortality data that are suitable for international comparisons.Methods: We used the Australian Bureau of Statistics Death Registrations to Census file, with data on deaths (2011-2012) linked probabilistically to census data (linkage rate 81%). To assess validity, we compared mortality rates by age group (25-44, 45-64, 65-84 years), sex and area-inequality measures to those based on complete death registration data. We used negative binomial regression to quantify inequalities in all-cause mortality in relation to five levels of education ['Bachelor degree or higher' (highest) to 'no Year 12 and no post-secondary qualification' (lowest)], separately by sex and age group, adjusting for single year of age and correcting for linkage bias and missing education data.Results: Mortality rates and area-based inequality estimates were comparable to published national estimates. Men aged 25-84 years with the lowest education had age-adjusted mortality rates 2.20 [95% confidence interval (CI): 2.08‒2.33] times those of men with the highest education. Among women, the rate ratio was 1.64 (1.55‒1.74). Rate ratios were 3.87 (3.38‒4.44) in men and 2.57 (2.15‒3.07) in women aged 25-44 years, decreasing to 1.68 (1.60‒1.76) in men and 1.44 (1.36‒1.53) in women aged 65-84 years. Absolute education inequalities increased with age. One in three to four deaths (31%) was associated with less than Bachelor level education.Conclusions: These linked national data enabled valid estimates of education inequality in mortality suitable for international comparisons. The magnitude of relative inequality is substantial and similar to that reported for other high-income countries. [ABSTRACT FROM AUTHOR]

Background: This study assessed the association between coal-mine-fire-related fine particulate matter (PM2.5) and medical-service utilization, following a 6-week coal-mine fire in Australia, in 2014. Areas in the immediate vicinity of the mine experienced hourly mine-fire-related PM2.5 concentrations of up to 3700 μg/m3.Methods: Data on medical-service utilization were collected from the Medicare Benefits Schedule-a national database of payment for medical services. PM2.5 concentrations were modelled using atmospheric chemical transport modelling. Quasi-Poisson interrupted distributed lag time-series analysis examined the association between daily mine-fire-related PM2.5 concentrations and medical-service utilization, including General Practitioner (GP) consultations and respiratory, cardiovascular and mental health services. Confounders included seasonality, long-term trend, day of the week, maximum daily temperature and public holidays. Gender and age stratification were conducted.Results: A 10-μg/m3 increase in PM2.5 was associated with an increased relative risk of service usage for all long and short GP consultations [11% (95% confidence interval: 7 to 15%)] and respiratory services [22% (4 to 43%)] in both men and women. Sex stratification found an increased relative risk in mental health consultations in men [32% (2 to 72%)] but not women. No associations were found for cardiovascular services in men or women.Conclusions: Coal-mine-fire-related PM2.5 exposure was associated with increased use of medical services for GP consultations and respiratory services in men and women and mental health consultations in men. These findings can inform the development of future public-health-policy responses in the event of major air-pollution episodes. [ABSTRACT FROM AUTHOR]

Background: The latest review of studies on multimorbidity patterns showed high heterogeneity in the methodology for identifying groups of multimorbid conditions. However, it is unclear how analytical methods used influence the identified multimorbidity patterns.Methods: We undertook a systematic review of analytical methods used to identify multimorbidity patterns in PubMed and EMBASE from their inception to January 2017. We conducted a comparison analysis to assess the effect the analytical methods had on the multimorbidity patterns identified, using the Australian National Health Survey (NHS) 2007-08 data.Results: We identified 13 194 studies and excluded 13 091 based on titles/abstracts. From the full-text reviews of the 103 remaining publications, we identified 41 studies that used five different analytical methods to identify multimorbid conditions in the studies. Thirty-seven studies (90%) adopted either the factor-analysis or hierarchical-clustering methods, but heterogeneity arises for the use of different proximity measures within each method to form clusters. Our comparison analysis showed the variation in identified groups of multimorbid conditions when applying the methods to the same NHS data. We extracted main similarities among the groupings obtained by the five methods: (i) cardiovascular and metabolic diseases, (ii) mental health problems and (iii) allergic diseases.Conclusion: We showed the extent of effects for heterogeneous analytical methods on identification of multimorbidity patterns. However, more work is needed to guide investigators for choosing the best analytical method to improve the validity and generalizability of findings. Investigators should also attempt to compare results obtained by various methods for a consensus grouping of multimorbid conditions. [ABSTRACT FROM AUTHOR]

Background: Disadvantage rarely manifests as a single event, but rather is the enduring context in which a child's development unfolds. We aimed to characterize patterns of stability and change in multiple aspects of disadvantage over the childhood period, in order to inform more precise and nuanced policy development.Methods: Participants were from the Longitudinal Study of Australian Children birth cohort (n = 5107). Four lenses of disadvantage (sociodemographic, geographic environment, health conditions and risk factors), and a composite of these representing average exposure across all lenses, were assessed longitudinally from 0 to 9 years of age. Trajectory models identified groups of children with similar patterns of disadvantage over time for each of these lenses and for composite disadvantage. Concurrent validity of these trajectory groups was examined through associations with academic performance at 10-11 years.Results: We found four distinct trajectories of children's exposure to composite disadvantage, which showed high levels of stability over time. In regard to the individual lenses of disadvantage, three exhibited notable change over time (the sociodemographic lens was the exception). Over a third of children (36.3%) were exposed to the 'most disadvantaged' trajectory in at least one lens. Trajectories of disadvantage were associated with academic performance, providing evidence of concurrent validity.Conclusions: Children's overall level of composite disadvantage was stable over time, whereas geographic environments, health conditions and risk factors changed over time for some children. Measuring disadvantage as uni-dimensional, at a single time point, is likely to understate the true extent and persistence of disadvantage. [ABSTRACT FROM AUTHOR]

Background: When information on changes in address or migration of people to or from a study jurisdiction is unavailable in longitudinal studies, issues relating to loss-to-follow-up and misclassification bias may result. This study investigated how estimations of associations between general practitioner (GP) contact and hospital use were affected by incomplete address and migration data.Methods: This was a retrospective population-based cohort study of Western Australians from 1990 to 2004. Linked administrative data including mortality records, hospital admissions, primary care and Electoral Roll records were used. Regularity of GP contact, based on the variance of the number of days between GP visits, was calculated for each person-year. Outcomes were the number and costs (A$2014) of diabetes-related hospital admissions in the following year. Models were estimated separately for cohorts where (i) postcode was ascertained at study commencement and held constant, and (ii) postcode and residency within Western Australia were updated with each change of address recorded on the Electoral Roll over the study period.Results: Updating address data reduced total person-years by 11% and changed the distribution of covariates. Estimations of associations between patterns of GP contact and number of hospitalizations changed; the incidence rate ratios measuring the relationship with the most regular GP contact (baseline of those with <2 GP visits) changed from 0.81 [95% confidence interval (CI) 0.66-1.00] to 0.42 (95% CI 0.33-0.53) after updating postcode information. Impacts on cost models were smaller, though still statistically significant.Conclusions: Longitudinal studies using administrative data may report biased results if they ignore address changes and migration. Researchers should attempt to link to these data wherever possible, or choose study designs which these issues are less likely to affect. Custodians should be aware that such data can be vital to high quality research. [ABSTRACT FROM AUTHOR]

Background: Mammographic density defined by the conventional pixel brightness threshold, and adjusted for age and body mass index (BMI), is a well-established risk factor for breast cancer. We asked if higher thresholds better separate women with and without breast cancer.Methods: We studied Australian women, 354 with breast cancer over-sampled for early-onset and family history, and 944 unaffected controls frequency-matched for age at mammogram. We measured mammographic dense area and percent density using the CUMULUS software at the conventional threshold, which we call Cumulus , and at two increasingly higher thresholds, which we call Altocumulus and Cirrocumulus , respectively. All measures were Box-Cox transformed and adjusted for age and BMI. We estimated the odds per adjusted standard deviation (OPERA) using logistic regression and the area under the receiver operating characteristic curve (AUC).Results: Altocumulus and Cirrocumulus were correlated with Cumulus (r ∼ 0.8 and 0.6 , respectively) . For dense area, the OPERA was 1.62, 1.74 and 1.73 for Cumulus, Altocumulus and Cirrocumulus , respectively (all P  < 0.001). After adjusting for Altocumulus and Cirrocumulus , Cumulus was not significant ( P  > 0.6). The OPERAs for percent density were less but gave similar findings. The mean of the standardized adjusted Altocumulus and Cirrocumulus dense area measures was the best predictor; OPERA = 1.87 [95% confidence interval (CI): 1.64-2.14] and AUC = 0.68 (0.65-0.71).Conclusions: The areas of higher mammographically dense regions are associated with almost 30% stronger breast cancer risk gradient, explain the risk association of the conventional measure and might be more aetiologically important. This has substantial implications for clinical translation and molecular, genetic and epidemiological research. [ABSTRACT FROM AUTHOR]

The Australian Parental Supply of Alcohol Longitudinal Study (APSALS) was established in 2010 to investigate the short- and long-term associations between exposure to early parental alcohol provision, early adolescent alcohol initiation, subsequent alcohol use and alcohol-related harms, controlling for a wide range of parental, child, familial, peer and contextual covariates. The cohort commenced with 1927 parent-child dyads comprising Australian Grade 7 school students (mean age = 12.9 years, range = 10.8-15.7 years), and a parent/guardian. Baseline, 1- and 2-year follow-up data have been collected, with > 90% retention, and a 3-year follow-up is under way. The data collected include child, familial, parental and peer factors addressing demographics, alcohol use and supply, parenting practices, other substance use, adolescent behaviours and peer influences. The cohort is ideal for prospectively examining predictors of initiation and progression of alcohol use, which increases markedly through adolescence. [ABSTRACT FROM AUTHOR]

Background: The Seven Countries Study in the 1960s showed very low mortality from coronary heart disease (CHD) in Japan, which was attributed to very low levels of total cholesterol. Studies of migrant Japanese to the USA in the 1970s documented increase in CHD rates, thus CHD mortality in Japan was expected to increase as their lifestyle became Westernized, yet CHD mortality has continued to decline since 1970. This study describes trends in CHD mortality and its risk factors since 1980 in Japan, contrasting those in other selected developed countries.Methods: We selected Australia, Canada, France, Japan, Spain, Sweden, the UK and the USA. CHD mortality between 1980 and 2007 was obtained from WHO Statistical Information System. National data on traditional risk factors during the same period were obtained from literature and national surveys.Results: Age-adjusted CHD mortality continuously declined between 1980 and 2007 in all these countries. The decline was accompanied by a constant fall in total cholesterol except Japan where total cholesterol continuously rose. In the birth cohort of individuals currently aged 50-69 years, levels of total cholesterol have been higher in Japan than in the USA, yet CHD mortality in Japan remained the lowest: >67% lower in men and > 75% lower in women compared with the USA. The direction and magnitude of changes in other risk factors were generally similar between Japan and the other countries.Conclusions: Decline in CHD mortality despite a continuous rise in total cholesterol is unique. The observation may suggest some protective factors unique to Japanese. [ABSTRACT FROM AUTHOR]

Indigenous Australians experience profound levels of disadvantage in health, living standards, life expectancy, education and employment, particularly in comparison with non-Indigenous Australians. Very little information is available about the healthy development of Australian Indigenous children; the Longitudinal Study of Indigenous Children (LSIC) is designed to fill this knowledge gap. This dataset provides an opportunity to follow the development of up to 1759 Indigenous children. LSIC conducts annual face-to-face interviews with children (aged 0.5-2 and 3.5-5 years at baseline in 2008) and their caregivers. This represents between 5% and 10% of the total population of Indigenous children in these age groups, including families of varied socioeconomic and cultural backgrounds. Study topics include: the physical, social and emotional well-being of children and their caregivers; language; culture; parenting; and early childhood education. LSIC is a shared resource, formed in partnership with communities; its data are readily accessible through the Australian Government Department of Social Services (see http:// dss.gov.au/lsic for data and access arrangements). As one of very few longitudinal studies of Indigenous children, and the only national one, LSIC will enable an understanding of Indigenous children from a wide range of environments and cultures. Findings from LSIC form part of a growing infrastructure from which to understand Indigenous child health. [ABSTRACT FROM AUTHOR]

In 1996 the Australian Longitudinal Study on Women's Health recruited a nationally representative sample of more than 40,000 women in three age cohorts, born in 1973-78, 1946-51 and 1921-26. At least six waves of 3-yearly surveys have been completed. Although the focus remains on factors affecting the health and well-being of women and their access to and use of health services across urban, rural and remote areas of Australia, the study has now been considerably expanded by linkage to other health data sets. For most women who have ever participated in the study, linked records are now available for: government-subsidized non-hospital services (e.g. all general practitioner visits); pharmaceutical prescriptions filled; national death index, including codes for multiple causes of death; aged care assessments and services; cancer registries; and, for most states and territories, hospital admissions and perinatal data. Additionally, a large cohort of women born in 1989-95 have been recruited. The data are available to approved collaborators, with more than 780 researchers using the data so far. Full details of the study materials and data access procedures are available at [http://www.alswh.org.au/]. [ABSTRACT FROM AUTHOR]