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To help health economic modelers respond to demands for greater use of complex systems models in public health. To propose identifiable features of such models and support researchers to plan public health modeling projects using these models. A working group of experts in complex systems modeling and economic evaluation was brought together to develop and jointly write guidance for the use of complex systems models for health economic analysis. The content of workshops was informed by a scoping review. A public health complex systems model for economic evaluation is defined as a quantitative, dynamic, non-linear model that incorporates feedback and interactions among model elements, in order to capture emergent outcomes and estimate health, economic and potentially other consequences to inform public policies. The guidance covers: when complex systems modeling is needed; principles for designing a complex systems model; and how to choose an appropriate modeling technique. This paper provides a definition to identify and characterize complex systems models for economic evaluations and proposes guidance on key aspects of the process for health economics analysis. This document will support the development of complex systems models, with impact on public health systems policy and decision making.

IntroductionThis study considers the prediction of the time until two survival outcomes have both occurred. We compared a variety of analytical methods motivated by a typical clinical problem of multimorbidity prognosis.MethodsWe considered five methods: product (multiply marginal risks), dual-outcome (directly model the time until both events occur), multistate models (msm), and a range of copula and frailty models. We assessed calibration and discrimination under a variety of simulated data scenarios, varying outcome prevalence, and the amount of residual correlation. The simulation focused on model misspecification and statistical power. Using data from the Clinical Practice Research Datalink, we compared model performance when predicting the risk of cardiovascular disease and type 2 diabetes both occurring.ResultsDiscrimination was similar for all methods. The product method was poorly calibrated in the presence of residual correlation. The msm and dual-outcome models were the most robust to model misspecification but suffered a drop in performance at small sample sizes due to overfitting, which the copula and frailty model were less susceptible to. The copula and frailty model's performance were highly dependent on the underlying data structure. In the clinical example, the product method was poorly calibrated when adjusting for 8 major cardiovascular risk factors.DiscussionWe recommend the dual-outcome method for predicting the risk of two survival outcomes both occurring. It was the most robust to model misspecification, although was also the most prone to overfitting. The clinical example motivates the use of the methods considered in this study.

Extracurricular activity participation is associated with positive academic, health, and behavioral outcomes for adolescents, but these findings may reflect unobserved confounding rather than participation effects.Data were drawn from 3885 adolescents aged 12-15 in a nationally representative cohort of Australian adolescents. Effects of participation in three kinds of extracurricular activity (team sport, individual sport, and arts) on an array of outcomes were modeled using fixed-effects regression to account for potential unobserved confounding.Strong bivariate relationships between all forms of activity participation and positive adolescent outcomes were found. These associations were much smaller in the fixed-effects analysis, but beneficial effects of sports for mental health and arts for peer group characteristics remained statistically significant. Minimal effects of extracurricular activity participation for academic achievement were found.Extracurricular activity participation has beneficial effects on adolescents' mental health and exposure to peers' delinquent behavior.

The knowledge about why hip fracture rates in Norway have declined is sparse. Concurrent with decreasing hip fracture rates, the rates of total hip replacements (THRs) have increased. We wanted to investigate if hip fracture rates continued to decline, and whether the increase in THRs had any influence on this decline, assuming that living with a hip prosthesis precludes fracture of the operated hip. Information on hip fractures in Norway 1999-2019 was available from the Norwegian Epidemiologic Osteoporosis Studies (NOREPOS) hip fracture database and population size were available in official population tables from Statistics Norway. Primary THRs (for any cause except hip fracture) 1989-2019 were obtained from the Norwegian Arthroplasty Register. We calculated the annual age-standardized incidence rates of hip fracture by sex for the period 1999–2019. The hip fracture rates in a scenario with no hip prostheses were calculated by subtracting 0.5 persons from the population at risk for each prevalent hip prosthesis, considering that each person has two hips at risk of fracture. We estimated how much of the decline could be attributed to the increased prevalence of hip prostheses. From 1999 to 2019, age-standardized incidence rates of hip fracture decreased by 27% in women and 20% in men. The rates remained stable in those under 70 years and decreased in those 70 years and above. Excluding replaced hips from the population at risk led to higher incidence rates, and this impact was considerably larger at higher ages. The increased prevalence of hip prostheses over the period accounted for approximately 18% (20% in women and 11% in men) of the observed decline in hip fracture rates. In conclusion, the incidence of hip fractures continued to decline, and the increasing number of people living with hip prostheses contributed significantly to the observed declining time trends.

This study combines minority stress and ecological perspectives to theorize the associations between adolescents' sexual orientation and time use. Hypotheses are tested using data from a national sample of Australian adolescents aged 14-15 years (Longitudinal Study of Australian Children; n = 3,060). Compared to heterosexual adolescents, sexual minority adolescents spent less time with their siblings and fathers, more time alone, less time in active leisure- and school-based activities, and more time in nonactive leisure. There were no differences between sexual minority and heterosexual adolescents in time spent with mothers, peers, and in screen-based leisure. Some associations were gendered. Collectively, the results suggest that sexual minority adolescents may withdraw or be excluded from critical developmental activities and the company of key social partners.

Aims From the pre-teen to the mid-teen years, rates of alcohol use and misuse increase rapidly. Cross-sectional research shows that positive family emotional climate (low conflict, high closeness) is protective, and there is emerging evidence that these protective mechanisms are different for girls versus boys. The aim of this study was to explore gender differences in the longitudinal impact of family emotional climate on adolescent alcohol use and exposure to peer drinking networks. Design Three-wave two-level (individual, within-individual over time) ordinal logistic regression with alcohol use in the past year as the dependent measure and family variables lagged by 1 year. Setting Adolescents completed surveys during school hours. Participants A total of 855 Australian students (modal age 10-11 years at baseline) participating in the International Youth Development Study (Victoria, Australia). Measurements These included emotional closeness to mother/father, family conflict, parent disapproval of alcohol use and peer alcohol use. Findings For girls, the effect of emotional closeness to mothers on alcohol use was mediated by exposure to high-risk peer networks. Parent disapproval of alcohol use was protective for both genders, but this effect was larger for boys versus girls, and there was no evidence that peer use mediated this effect. Peer drinking networks showed stronger direct risk effects than family variables. Conclusions Family factors unidirectionally impact on growth in adolescent alcohol use and effects vary with child gender.

Despite considerable success in tobacco control, many teenagers in Australia and other industrialised countries still smoke tobacco. There is mixed evidence on the relative influence of proximal social networks (parents/siblings/peers) on pre- and early-teen smoking, and no research has examined how these influences compare after accounting for school and community level effects. Aim: To compare the relative influences of parents, siblings, and peers, after accounting for school and community-level variation in smoking. Design: A cross-sectional fixed and random effects model of smoking prevalence was used, with individuals (n = 7314) nested within schools (n = 231) nested within communities (n = 30). Participants: Grade 6 and 8 students (modal ages 11 and 13 years) completed an on-line survey. Measurements: Key variables included parent/sibling/peer use. Controls included alcohol involvement, sensation seeking, pro-social beliefs, laws/norms about substance use, and school commitment. Findings: There was significant variation in smoking at both the school and community levels, supporting the need for a multi-level model. Individual level predictors accounted for much of the variance at higher levels. The strongest effects were for number of friends who smoke, sibling smoking, and alcohol involvement. Smaller significant effects were found for parent smoking. At the community level, socioeconomic disadvantage was significant, but community-level variance in pro-social and drug-related laws norms was not related to smoking. Cross-level interactions were generally non-significant. Conclusion: Early teenage smoking was best explained by sibling and peer smoking, and individual risks largely accounted for the substantial variation observed across schools and communities

To study the efficacy of a treatment strategy for the management of hypertensive urgencies, the authors evaluated 549 patients admitted to the emergency department. They were first assigned to a 30-minute rest period, then a follow-up blood pressure measurement was carried out. Patients who did not respond to rest were randomly assigned to receive an oral dose of an antihypertensive drug with different mechanisms of action and pharmacodynamic properties (perindopril, amlodipine, or labetalol), and blood pressure was reassessed at 60- and 120-minute intervals. A satisfactory blood pressure response to rest (defined as postintervention systolic blood pressure < 180 mm Hg and diastolic blood pressure < 110 mm Hg, with at least a 20 mm Hg reduction in basal systolic blood pressure and/or a 10-mm Hg reduction in basal diastolic blood pressure) was observed in 31.9% of population. Among nonresponders, 79.1% had a satisfactory blood pressure response to the antihypertensive drug treatment in a 2-hour average follow-up period. No major adverse events were observed. This treatment strategy, based on standardized rest as an initial step and different antihypertensive drugs, can be effective and safe for the management of patients with hypertensive urgencies.

Since the early 1980s Australian public policy has undergone the most major transformation since Federation. This transformation has been underwritten by two key principles: liberalism - the view that citizens are autonomous individual actors whose interests are best served when they are free from coercive government interventions into individual action; and marketisation - the belief that free markets are arenas which best enable individual autonomy and produce efficient economic outcomes. These principles define 'neoliberalism' or 'hard liberalism'. After summarising the major policy changes identified with neoliberalism in Australia, the paper introduces a new research project that examines its impact on socioeconomic inequality, gender inequality and politics and culture. Inspection of relevant data indicates that there are important trends in inequality, public opinion and political behaviour that warrant this investigation.

This essay addresses the impacts of electronic tenancy databases upon social relations in the field of private rental tenancy in Australia. Insights arise from research carried out, in 2002–3, in the eastern, mainland states of Australia that included interviews with tenants and property managers in the private rental sector. Property managers viewed tenancy databases as a tool for efficient, effective and professional risk management, and ‘professional’ practice was held to render misconduct or improper listings extremely unlikely. In this context, tenants were individualized and expected to actively work to construct, maintain and document their reputation as a ‘good tenant’. For tenants, tenancy databases could have a particular, definitive effect. ‘Not being listed’ (along with getting a full rental bond refund, references from previous landlords, and so on) is an indicator that helps build a satisfactory, personal rental history. On the other hand, being ‘listed’ is read as a prime indicator of risk and effectively overriding other aspects of a tenant’s application for tenancy. ‘Listed’ tenants find themselves being forced to shift further and further away from the formal rental market and ultimately into insecure and inappropriate housing arrangements at the periphery.