The impact of re-opening the international border on COVID-19 hospitalisations in Australia: a modelling study.

OBJECTIVE: To estimate the numbers of COVID-19-related hospitalisations in Australia after re-opening the international border. DESIGN: Population-level deterministic compartmental epidemic modelling of eight scenarios applying various assumptions regarding SARS-CoV-2 transmissibility (baseline R0 = 3.5 or 7.0), vaccine rollout speed (slow or fast), and scale of border re-opening (mean of 2500 or 13 000 overseas arrivals per day). SETTING: Simulation population size, age structure, and age-based contact rates based on recent estimates for the Australian population. We assumed that 80% vaccination coverage of people aged 16 years or more was reached in mid-October 2021 (fast rollout) or early January 2022 (slow rollout). MAIN OUTCOME MEASURES: Numbers of people admitted to hospital with COVID-19, December 2021 - December 2022. RESULTS: In scenarios assuming a highly transmissible SARS-CoV-2 variant (R0  = 7.0), opening the international border on either scale was followed by surges in both infections and hospitalisations that would require public health measures beyond mask wearing and social distancing to avoid overwhelming the health system. Reducing the number of hospitalisations to manageable levels required several cycles of additional social and mobility restrictions. CONCLUSIONS: If highly transmissible SARS-CoV-2 variants are circulating locally or overseas, large and disruptive COVID-19 outbreaks will still be possible in Australia after 80% of people aged 16 years or more have been vaccinated. Continuing public health measures to restrict the spread of disease are likely to be necessary throughout 2022.

Modelling vaccination capacity at mass vaccination hubs and general practice clinics: a simulation study.

BACKGROUND: COVID-19 mass vaccination programs place an additional burden on healthcare services. We aim to model the queueing process at vaccination sites to inform service delivery. METHODS: We use stochastic queue network models to simulate queue dynamics in larger mass vaccination hubs and smaller general practice (GP) clinics. We estimate waiting times and daily capacity based on a range of assumptions about appointment schedules, service times and staffing and stress-test these models to assess the impact of increased demand and staff shortages. We also provide an interactive applet, allowing users to explore vaccine administration under their own assumptions. RESULTS: Based on our assumed service times, the daily throughput for an eight-hour clinic at a mass vaccination hub ranged from 500 doses for a small hub to 1400 doses for a large hub. For GP clinics, the estimated daily throughput ranged from about 100 doses for a small practice to almost 300 doses for a large practice. What-if scenario analysis showed that sites with higher staff numbers were more robust to system pressures and mass vaccination sites were more robust than GP clinics. CONCLUSIONS: With the requirement for ongoing COVID-19 booster shots, mass vaccination is likely to be a continuing feature of healthcare delivery. Different vaccine sites are useful for reaching different populations and maximising coverage. Stochastic queue networks offer a flexible and computationally efficient approach to simulate vaccination queues and estimate waiting times and daily throughput to inform service delivery.

Medications used disproportionately during pregnancy: Priorities for research on the risks and benefits of medications when used during pregnancy.

PURPOSE: To identify medications used disproportionately more or less among pregnant women relative to women of childbearing age. METHODS: Medication use among pregnant women in New South Wales, Australia was identified using linked perinatal and pharmaceutical dispensing data from 2006 to 2012. Medication use in women of childbearing age (including pregnant women) was identified using pharmaceutical dispensing data for a 10% random sample of the Australian population. Pregnant social security beneficiaries (n = 111 612) were age-matched (1:3) to female social security beneficiaries in the 10% sample. For each medication, the risk it was dispensed during pregnancy relative to being dispensed during an equivalent time period among matched controls was computed. Medications were mapped to Australian pregnancy risk categories. RESULTS: Of the 181 included medications, 35 were statistically significantly more commonly dispensed to pregnant women than control women. Of these, 23 are categorised as posing no increased risk to the foetus. Among medications suspected of causing harm or having insufficient safety data, the strongest associations were observed for hydralazine, ondansetron, dalteparin sodium and ranitidine. Use was less likely during pregnancy than control periods for 127 medications, with the strongest associations observed for hormonal contraceptives and progestogens. CONCLUSIONS: Most medications found to be used disproportionately more by pregnant women are indicated for pregnancy-related problems. A large number of medications were used disproportionately less among pregnant women, where avoidance of some of these medications may pose a greater risk of harm. For many other medications avoided during pregnancy, current data are insufficient to inform this risk-benefit assessment.

Pregnancy and birth characteristics of Aboriginal twins in two Australian states: a data linkage study.

INTRODUCTION: Perinatal outcomes for singleton pregnancies are poorer, on average, for Aboriginal people than non-Aboriginal people, but little is known about Aboriginal multifetal pregnancies. Yet multifetal pregnancies and births are often more complicated and have poorer outcomes than singleton pregnancies. We describe the pregnancies, births and perinatal outcomes for Aboriginal twins born in Western Australia (WA) and New South Wales (NSW) with comparisons to Aboriginal singletons in both states and to non-Aboriginal births in NSW. MATERIALS AND METHODS: Whole-population birth records and birth and death registrations were linked for all births during 2000-2013 (WA) and 2002-2008 (NSW). Hospital records and the WA Register of Developmental Anomalies - Cerebral Palsy were linked for all WA births and hospital records for a subset of NSW births. Descriptive statistics are reported for maternal and child demographics, maternal health, pregnancy complications, births and perinatal outcomes. RESULTS: Thirty-four thousand one hundred twenty-seven WA Aboriginal, 32,352 NSW Aboriginal and 601,233 NSW non-Aboriginal births were included. Pregnancy complications were more common among mothers of Aboriginal twins than Aboriginal singletons (e.g. 17% of mothers of WA twins had hypertension/pre-eclampsia/eclampsia vs 8% of mothers of singletons) but similar to mothers of NSW non-Aboriginal twins. Most Aboriginal twins were born in a principal referral, women's or large public hospital. The hospitals were often far from the mother's home (e.g. 31% of mothers of WA Aboriginal twins gave birth at hospitals located more than 3 h by road from their home). Outcomes were worse for Aboriginal liveborn twins than Aboriginal singletons and non-Aboriginal twins (e.g. 58% of NSW Aboriginal twins were preterm compared to 9% of Aboriginal singletons and 49% non-Aboriginal twins). CONCLUSIONS: Mothers of Aboriginal twins faced significant challenges during the pregnancy, birth and the postnatal period in hospital and, in addition to accessible specialist medical care, these mothers may need extra practical and psychosocial support throughout their journey.

Social and emotional developmental vulnerability at age five in Aboriginal and non-Aboriginal children in New South Wales: a population data linkage study.

BACKGROUND: Early childhood social and emotional development underpins later social, emotional, academic and other outcomes. The first aim of this study was to explore the association between child, family and area-level characteristics associated with developmental vulnerability, amongst Aboriginal and non-Aboriginal children in their first year of school. The second aim was to quantify the magnitude of the social and emotional developmental inequalities between Aboriginal and non-Aboriginal children and the extent to which differences in socioeconomic disadvantage and perinatal characteristics explained this inequality. METHODS: This retrospective cohort study used cross-sectoral data linkage to identify and follow participants from birth to school age. In this way, social and emotional development was examined in 7,384 Aboriginal and 95,104 non-Aboriginal children who were included in the Australian Early Development Census in their first year of full-time school in New South Wales (NSW) in 2009 or 2012 and had a birth registration and/or perinatal record in NSW. The primary outcome measures were teacher-reported social competence and emotional maturity as measured using the Australian version of the Early Development Instrument. RESULTS: The mean age at the start of the school year for children in the study sample was 5.2 years (SD = 0.36 years). While 84% of Aboriginal children scored favourably - above the vulnerability threshold - for social competence and 88% for emotional maturity, Aboriginal children were twice as likely as non-Aboriginal children to be vulnerable on measures of social development (RR = 2.00; 95%CI, 1.89-2.12) and had 89% more risk of emotional vulnerability (RR = 1.89; 95%CI, 1.77-2.02). The inequality between Aboriginal and non-Aboriginal children was largely explained by differences in the socioeconomic and perinatal health characteristics of children and families. Thus, after adjusting for differences in measures of socioeconomic advantage and disadvantage (Model 2), the relative risk was attenuated to 1.31 (95% CI: 1.23-1.40) on the social competence domain and 1.24 (95% CI, 1.15-1.33) on the emotional maturity domain. Child, family and area-level characteristics associated with vulnerability were identified. CONCLUSIONS: Most of the gap in early childhood social and emotional development between Aboriginal and non-Aboriginal children can be attributed to socioeconomic and early life health disadvantage. Culturally safe health and social policies addressing the socioeconomic and health inequalities experienced by Aboriginal children are urgently required.

Maternal age and offspring developmental vulnerability at age five: A population-based cohort study of Australian children.

BACKGROUND: In recent decades, there has been a shift to later childbearing in high-income countries. There is limited large-scale evidence of the relationship between maternal age and child outcomes beyond the perinatal period. The objective of this study is to quantify a child's risk of developmental vulnerability at age five, according to their mother's age at childbirth. METHODS AND FINDINGS: Linkage of population-level perinatal, hospital, and birth registration datasets to data from the Australian Early Development Census (AEDC) and school enrolments in Australia's most populous state, New South Wales (NSW), enabled us to follow a cohort of 99,530 children from birth to their first year of school in 2009 or 2012. The study outcome was teacher-reported child development on five domains measured by the AEDC, including physical health and well-being, emotional maturity, social competence, language and cognitive skills, and communication skills and general knowledge. Developmental vulnerability was defined as domain scores below the 2009 AEDC 10th percentile cut point. The mean maternal age at childbirth was 29.6 years (standard deviation [SD], 5.7), with 4,382 children (4.4%) born to mothers aged <20 years and 20,026 children (20.1%) born to mothers aged ≥35 years. The proportion vulnerable on ≥1 domains was 21% overall and followed a reverse J-shaped distribution according to maternal age: it was highest in children born to mothers aged ≤15 years, at 40% (95% CI, 32-49), and was lowest in children born to mothers aged between 30 years and ≤35 years, at 17%-18%. For maternal ages 36 years to ≥45 years, the proportion vulnerable on ≥1 domains increased to 17%-24%. Adjustment for sociodemographic characteristics significantly attenuated vulnerability risk in children born to younger mothers, while adjustment for potentially modifiable factors, such as antenatal visits, had little additional impact across all ages. Although the multi-agency linkage yielded a broad range of sociodemographic, perinatal, health, and developmental variables at the child's birth and school entry, the study was necessarily limited to variables available in the source data, which were mostly recorded for administrative purposes. CONCLUSIONS: Increasing maternal age was associated with a lesser risk of developmental vulnerability for children born to mothers aged 15 years to about 30 years. In contrast, increasing maternal age beyond 35 years was generally associated with increasing vulnerability, broadly equivalent to the risk for children born to mothers in their early twenties, which is highly relevant in the international context of later childbearing. That socioeconomic disadvantage explained approximately half of the increased risk of developmental vulnerability associated with younger motherhood suggests there may be scope to improve population-level child development through policies and programs that support disadvantaged mothers and children.

Gestational Age and Child Development at Age Five in a Population-Based Cohort of Australian Aboriginal and Non-Aboriginal Children.

BACKGROUND: Preterm birth and developmental vulnerability are more common in Australian Aboriginal compared with non-Aboriginal children. We quantified how gestational age relates to developmental vulnerability in both populations. METHODS: Perinatal datasets were linked to the Australian Early Development Census (AEDC), which collects data on five domains, including physical, social, emotional, language/cognitive, and general knowledge/communication development. We quantified the risk of developmental vulnerability on ≥1 domains at age 5, according to gestational age and Aboriginality, for 97 989 children born in New South Wales, Australia, who started school in 2009 or 2012. RESULTS: Seven thousand and seventy-nine children (7%) were Aboriginal. Compared with non-Aboriginal children, Aboriginal children were more likely to be preterm (5% vs. 9%), and developmentally vulnerable on ≥1 domains (20% vs. 36%). Overall, the proportion of developmentally vulnerable children decreased with increasing gestational age, from 44% at ≤27 weeks to 20% at 40 weeks. Aboriginal children had higher risks than non-Aboriginal children across the gestational age range, peaking among early term children (risk difference [RD] 19.0, 95% confidence interval [CI] 16.3, 21.7; relative risk [RR] 1.91, 95% CI 1.77, 2.06). The relation of gestational age to developmental outcomes was the same in Aboriginal and non-Aboriginal children, and adjustment for socio-economic disadvantage attenuated the risk differences and risk ratios across the gestational age range. CONCLUSIONS: Although the relation of gestational age to developmental vulnerability was similar in Aboriginal and non-Aboriginal children, Aboriginal children had a higher risk of developmental vulnerability at all gestational ages, which was largely accounted for by socio-economic disadvantage.

The effect of the 'Swim Reaper' program on water safety awareness, drowning mortality and morbidity among males aged 15-34 years in Aotearoa, New Zealand.

BACKGROUND AND OBJECTIVE: To increase water safety awareness among young males New Zealand introduced the Swim Reaper program in 2016. The program ran annually over summer and in 2018/19 an evaluation was conducted. The objective of this study was to evaluate the impact of the 2018/19 Swim Reaper social media-based campaign on self-reported water safety awareness and identify changes in fatal and nonfatal drowning rates for New Zealand resident males aged 15-34 years before and after the 2016 Swim Reaper program. METHODS: Online surveys pre (December-2018) and post (February-March-2019) Swim Reaper campaign were used to estimate water safety awareness post-campaign relative to pre-campaign using negative binomial regression adjusted for potential confounders. Interrupted time series (ITS) analysis, adjusted for seasonality, explored changes in drowning mortality, hospital admissions and Accident Compensation Corporation (ACC) claims pre and post program introduction (2016). RESULTS: A total of 518 males responded (50.6% post-campaign). There were significant improvements (post vs. pre-campaign) in self-reported water safety awareness. ITS analysis showed a reduction in drowning related hospital admissions post relative to pre-program (RR = 0.47; [95%CI: 0.24-0.90]; p = 0.02). DISCUSSION: Young males are an at-risk cohort for drowning and creating behavior change among this group can be challenging. Using a unique, humor-based approach the Swim Reaper program appears to be having some impact on self-reported water safety behaviors, as well as unintentional drowning-related hospitalization rates. Further evaluation, more clearly linked to campaign themes, is required to ascertain direct impact of the program. CONCLUSION: The novelty and reach of the campaign within the context of a prevailing downward trend in drownings may provide support for social media-based programs targeting this hard-to-reach demographic.

Readmission to a non-index hospital following total joint replacement.

Aims: It is unclear whether mortality outcomes differ for patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) surgery who are readmitted to the index hospital where their surgery was performed, or to another hospital. Methods: We analyzed linked hospital and death records for residents of New South Wales, Australia, aged ≥ 18 years who had an emergency readmission within 90 days following THA or TKA surgery between 2003 and 2022. Multivariable modelling was used to identify factors associated with non-index readmission and to evaluate associations of readmission destination (non-index vs index) with 90-day and one-year mortality. Results: Of 394,248 joint arthroplasty patients (THA = 149,456; TKA = 244,792), 9.5% (n = 37,431) were readmitted within 90 days, and 53.7% of these were admitted to a non-index hospital. Non-index readmission was more prevalent among patients who underwent surgery in private hospitals (60%). Patients who were readmitted for non-orthopaedic conditions (62.8%), were more likely to return to a non-index hospital compared to those readmitted for orthopaedic complications (39.5%). Factors associated with non-index readmission included older age, higher socioeconomic status, private health insurance, and residence in a rural or remote area. Non-index readmission was significantly associated with 90-day (adjusted odds ratio (aOR) 1.69; 95% confidence interval (CI) 1.39 to 2.05) and one-year mortality (aOR 1.31; 95% CI 1.16 to 1.47). Associations between non-index readmission and mortality were similar for patients readmitted with orthopaedic and non-orthopaedic complications (90-day mortality aOR 1.61; 95% CI 0.98 to 2.64, and aOR 1.67; 95% CI 1.35 to 2.06, respectively). Conclusion: Non-index readmission was associated with increased mortality, irrespective of whether the readmission was for orthopaedic complications or other conditions.

Developmental trajectories of socio-emotional outcomes of children and young people in out-of-home care - Insights from data of Pathways of Care Longitudinal Study (POCLS).

BACKGROUND: There has been a limited understanding of the longitudinal trajectory and determinants of socio-emotional outcomes among children in out-of-home care (OOHC). OBJECTIVES: This study aimed to examine child socio-demographics, pre-care maltreatment, placement, and caregiver factors associated with trajectories of socio-emotional difficulties of children in OOHC. PARTICIPANTS AND SETTING: The study sample (n = 345) included data from the Pathways of Care Longitudinal Study (POCLS), a prospective longitudinal cohort of children aged 3-17 years who entered the OOHC system in New South Wales (NSW) Australia, between 2010 and 2011. METHODS: Group-based trajectory models were used to identify distinct socio-emotional trajectory groups based on the Child Behaviour Check List (CBCL) Total Problem T-scores completed at all four Waves 1-4. Modified Poisson regression analysis was conducted to assess the association (risk ratios) of socio-emotional trajectory group membership with pre-care maltreatment, placement, and caregiver-related factors. RESULTS: Three trajectories of socio-emotional development were identified: 'persistently low difficulties' (average CBCL T-score changed from 40 to 38 over time), normal (average CBCL T-score changed from 52 to 55 over time), and clinical (average CBCL T-score remained at 68 over time) trajectories. Each trajectory presented a stable trend over time. Relative/kinship care, as compared with foster care, was associated with the "persistently low" socio-emotional trajectory. Being male, exposure to ≥8 pre-care substantiated risk of significant harm (ROSH) reports, placement changes, and caregiver's psychological distress (more than two-fold increased risk) were associated with the clinical socio-emotional trajectory. CONCLUSIONS: Early intervention to ensure children have a nurturing care environment and psychological support to caregivers are vital for positive socio-emotional development over time among children in long-term OOHC.

Enriching Data Science and Health Care Education: Application and Impact of Synthetic Data Sets Through the Health Gym Project.

Large-scale medical data sets are vital for hands-on education in health data science but are often inaccessible due to privacy concerns. Addressing this gap, we developed the Health Gym project, a free and open-source platform designed to generate synthetic health data sets applicable to various areas of data science education, including machine learning, data visualization, and traditional statistical models. Initially, we generated 3 synthetic data sets for sepsis, acute hypotension, and antiretroviral therapy for HIV infection. This paper discusses the educational applications of Health Gym's synthetic data sets. We illustrate this through their use in postgraduate health data science courses delivered by the University of New South Wales, Australia, and a Datathon event, involving academics, students, clinicians, and local health district professionals. We also include adaptable worked examples using our synthetic data sets, designed to enrich hands-on tutorial and workshop experiences. Although we highlight the potential of these data sets in advancing data science education and health care artificial intelligence, we also emphasize the need for continued research into the inherent limitations of synthetic data.

Fatal caffeine overdose: a case report and review of literature.

Caffeine is a central nervous system stimulant that is consumed by large numbers of people on a routine basis, usually in the form of coffee or tea. However, if consumed in high doses, this xanthine alkaloid is profoundly toxic and can result in death. Increasingly being sold as a dietary supplement, many people, particularly those in the health and fitness community, where it is touted as a fitness and muscle building aid, are consuming caffeine anhydrous on a daily basis. We report a case of fatal caffeine overdose in a 39-year-old man resulting from the self-administered ingestion of approximately 12 g of pure caffeine anhydrous. Autopsy blood caffeine levels were 350 mg/L. We recommend mandated labeling of pure caffeine anhydrous, highlighting the toxicity risk of ingesting this chemical; and we recommend ensuring that caffeine levels are included in the comprehensive forensic toxicology panel performed on all cases.

Software Application Profile: The daggle app-a tool to support learning and teaching the graphical rules of selecting adjustment variables using directed acyclic graphs.

MOTIVATION: Directed acyclic graphs (DAGs) are used in epidemiological research to communicate causal assumptions and guide the selection of covariate adjustment sets when estimating causal effects. For any given DAG, a set of graphical rules can be applied to identify minimally sufficient adjustment sets that can be used to adjust for bias due to confounding when estimating the causal effect of an exposure on an outcome. The daggle app is a web-based application that aims to assist in the learning and teaching of adjustment set identification using DAGs. GENERAL FEATURES: The application offers two modes: tutorial and random. The tutorial mode presents a guided introduction to how common causal structures can be presented using DAGs and how graphical rules can be used to identify minimally sufficient adjustment sets for causal estimation. The random mode tests this understanding by presenting the user with a randomly generated DAG-a daggle. To solve the daggle, users must correctly identify a valid minimally sufficient adjustment set. IMPLEMENTATION: The daggle app is implemented as an R shiny application using the golem framework. The application builds upon existing R libraries including pcalg to generate reproducible random DAGs, dagitty to identify all valid minimal adjustment sets and ggdag to visualize DAGs. AVAILABILITY: The daggle app can be accessed online at [http://cbdrh.shinyapps.io/daggle]. The source code is available on GitHub [https://github.com/CBDRH/daggle] and is released under a Creative Commons CC BY-NC-SA 4.0 licence.

An interactive geographic information system to inform optimal locations for healthcare services.

Large health datasets can provide evidence for the equitable allocation of healthcare resources and access to care. Geographic information systems (GIS) can help to present this data in a useful way, aiding in health service delivery. An interactive GIS was developed for the adult congenital heart disease service (ACHD) in New South Wales, Australia to demonstrate its feasibility for health service planning. Datasets describing geographic boundaries, area-level demographics, hospital driving times, and the current ACHD patient population were collected, linked, and displayed in an interactive clinic planning tool. The current ACHD service locations were mapped, and tools to compare current and potential locations were provided. Three locations for new clinics in rural areas were selected to demonstrate the application. Introducing new clinics changed the number of rural patients within a 1-hour drive of their nearest clinic from 44·38% to 55.07% (79 patients) and reduced the average driving time from rural areas to the nearest clinic from 2·4 hours to 1·8 hours. The longest driving time was changed from 10·9 hours to 8·9 hours. A de-identified public version of the GIS clinic planning tool is deployed at https://cbdrh.shinyapps.io/ACHD_Dashboard/. This application demonstrates how a freely available and interactive GIS can be used to aid in health service planning. In the context of ACHD, GIS research has shown that adherence to best practice care is impacted by patients' accessibility to specialist services. This project builds on this research by providing opensource tools to build more accessible healthcare services.

Uptake of Team Care Arrangements for adults newly diagnosed with cancer.

BACKGROUND: Medicare-subsidised Team Care Arrangements (TCAs) support Australian general practitioners to implement shared care between collaborating health professionals for patients with chronic medical conditions and complex needs. We assessed the prevalence of TCAs, factors associated with TCA uptake and visits to TCA-subsidised allied health practitioners, for adults newly diagnosed with cancer in New South Wales, Australia. METHODS: We carried out a retrospective individual patient data linkage study with 13 951 45 and Up Study participants diagnosed with incident cancer during 2006-16. We used a proportional hazards model to estimate the factors associated with receipt of a TCA after cancer diagnosis. RESULTS: In total, 6630 patients had a TCA plan initiated (47.5%). A TCA was more likely for patients aged ≥65years, those with higher service utilisation 4-15months prior to cancer diagnosis, a higher number of comorbidities, lower self-rated overall health status, living in areas of greater socio-economic disadvantage, lower educational attainment and those with no private health insurance. A total of 4084 (61.6%) patients with a TCA had at least one TCA-subsidised allied health visit within 24months of the TCA. CONCLUSIONS: TCAs appear to be well targeted at cancer patients with chronic health conditions and lower socioeconomic status. Nevertheless, not all patients with a TCA subsequently attended a TCA-subsidised allied healthcare professional. This suggests either a misunderstanding of the plan, the receipt of allied health via other public schemes, a low prioritisation of the plan compared to other health care, or suboptimal availability of these services.

Vaccinating Australia: How long will it take?

The Australian Government began to roll out the national COVID-19 vaccination program in late February 2021, with the initial aim to vaccinate the Australian adult population by the end of October 2021. The task of vaccinating some 20 million people presents considerable logistic challenges, but a rapid rollout is essential to allow for the reopening of borders and is especially urgent as new more transmissible variants arise. Here, we run a series of projections to estimate how long it will take to vaccinate the Australian population under different assumptions about the rate of vaccine administration, the schedule for vaccine eligibility and prevalence of vaccine hesitancy. Our analysis highlights the number of vaccine doses that can be administered per day as the key factor determining the duration of the vaccine rollout. A rate of 200,000 doses per day would achieve 90% population coverage by the end of 2021; 80,000 doses a day would see the rollout extended until mid-2023. Vaccine hesitancy has the potential to greatly slow down the rollout and becomes the main limiting factor when the supply of vaccine doses is high. Speed is of the essence when it comes vaccinating populations against COVID-19: a rapid rollout will minimise the risk of sporadic and costly lockdowns and the potential for small, local clusters getting out of control and sparking new epidemic waves. In order to achieve rapid population coverage, the Australian government must ramp up vaccine administration to at least 200,000 doses per day as quickly as possible, while also promoting vaccine willingness in the community through clear public health messaging, especially to known hesitant demographics.

Children's Relative Age and Medicine Treatment for Attention-Deficit/Hyperactivity Disorder Across Australian Jurisdictions with Different School Enrolment Policies.

Background: Children who are relatively young for their school grade are more likely to receive treatment for attention-deficit/hyperactivity disorder (ADHD). It is unclear whether the phenomenon also exists across Australia or is impacted by the school enrolment policy in place. Objective: We evaluated the association between children's relative age and initiation of ADHD medicines across Australian jurisdictions with different school enrolment policies and rates of delayed school entry. Methods: We used Australia-wide dispensing data for a 15% random sample of children 4-9 years of age in 2013-2017 to create a nationwide cohort. Due to high rates of delayed school entry in New South Wales (NSW), we used linked prescribing and education data for a cohort of NSW residents starting school in 2009 and 2012. We estimated incidence rate ratios (IRRs) for ADHD medicine across children's birth month, sex, and jurisdiction. We used asthma medicines as a negative control. Results: For girls, we observed a relative age effect in three out of five jurisdictions, with an IRR ranging from 1.3 to 2.8, comparing the youngest versus oldest birth month thirds. We observed more modest effects among boys, ranging from null to 1.5-fold. In NSW, the relatively youngest boys were less likely to initiate stimulant medicines than the oldest (IRR = 0.5, 95% confidence interval 0.29-0.78). We did not observe a relative age effect for initiation of asthma medicines. Conclusions: In jurisdictions with low rates of delayed entry, relatively young children were more likely to initiate ADHD medicines than their older classmates. We observed the inverse association in NSW where delayed entry was highest, likely reflecting the characteristics and needs of children who delay school entry for 1 year and become the oldest children in the grade. Increased awareness around children's maturity differences and school readiness may enhance appropriate diagnosis and treatment of ADHD.

Estimating incidence rates of periprosthetic joint infection after hip and knee arthroplasty for osteoarthritis using linked registry and administrative health data.

AIMS: The aim of this study was to estimate the 90-day periprosthetic joint infection (PJI) rates following total knee arthroplasty (TKA) and total hip arthroplasty (THA) for osteoarthritis (OA). METHODS: This was a data linkage study using the New South Wales (NSW) Admitted Patient Data Collection (APDC) and the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), which collect data from all public and private hospitals in NSW, Australia. Patients who underwent a TKA or THA for OA between 1 January 2002 and 31 December 2017 were included. The main outcome measures were 90-day incidence rates of hospital readmission for: revision arthroplasty for PJI as recorded in the AOANJRR; conservative definition of PJI, defined by T84.5, the PJI diagnosis code in the APDC; and extended definition of PJI, defined by the presence of either T84.5, or combinations of diagnosis and procedure code groups derived from recursive binary partitioning in the APDC. RESULTS: The mean 90-day revision rate for infection was 0.1% (0.1% to 0.2%) for TKA and 0.3% (0.1% to 0.5%) for THA. The mean 90-day PJI rates defined by T84.5 were 1.3% (1.1% to 1.7%) for TKA and 1.1% (0.8% to 1.3%) for THA. The mean 90-day PJI rates using the extended definition were 1.9% (1.5% to 2.2%) and 1.5% (1.3% to 1.7%) following TKA and THA, respectively. CONCLUSION: When reporting the revision arthroplasty for infection, the AOANJRR substantially underestimates the rate of PJI at 90 days. Using combinations of infection codes and PJI-related surgical procedure codes in linked hospital administrative databases could be an alternative way to monitor PJI rates.Cite this article: Bone Joint J 2022;104-B(9):1060-1066.

Histopathological Findings Related to ORISE™ Injectable Submucosa Lifting Agent Used in the Endoscopic Mucosal Resection of Bowel Neoplasms: A Review of Three Cases.

The use of nonsaline injectable lifting agents is now routine in the performance of endoscopic mucosal resection of bowel neoplasms (EMR). These agents are used to elevate the mucosa from the muscularis propria and permit more a complete resection of the lesion while mitigating risk of possible thermal injury to the bowel wall and thus preventing perforation. After injection, these new agents, which are replacing normal saline, often remain present in the tissues for some time following the procedure and may be identified in the resection specimens where they may mimic a number of other conditions such as mucin pools, lymphangiomas, granulomatous inflammation, and amyloid deposition. We describe the histological findings associated with the use of nonsaline injectable mucosal lifting agents. Awareness of these agents and their associated artefact may reduce misdiagnosis or the use of unnecessary ancillary studies and highlights the importance of proving relevant clinical information on submission of specimens for pathological examination.