Jane Lyons

All Wales Injury Surveillance System revised: development of a population-based system to evaluate single-level and multilevel interventions

Background Injury surveillance has been established since the 1990s, but is still largely based upon single-source data from sentinel sites. The growth of electronic health records and developments in privacy protecting linkage technologies provide an opportunity for more sophisticated surveillance systems. Objective To describe the evolution of an injury surveillance system to support the evaluation of interventions, both simple and complex in terms of organisation. Methods The paper describes the evolution of the system from one that relied upon data only from emergency departments to one that include multisource data and are now embedded in a total population privacy protecting data linkage system. Injury incidence estimates are compared by source and data linkage used to aid understanding of data quality issues. Examples of applications, challenges and solutions are described. Results The age profile and estimated incidence of injuries recorded in general practice, emergency departments and hospital admissions differ considerably. Data linkage has enabled the evaluation of complex interventions and measurement of longer-term impact of a wide range of exposures. Conclusions Embedding injury surveillance within privacy protecting data linkage environment can transform the utility of a traditional single-source surveillance system to a multisource system. It also facilitates greater involvement in the evaluation of simple and complex healthcare and non-healthcare interventions and contributes to the growing evidence basis underlying the science of injury prevention and control.

Creating individual level air pollution exposures in an anonymised data safe haven: a platform for evaluating impact on educational attainment

Abstract Introduction There is a lack of evidence on the adverse effects of air pollution on cognition for people with air quality-related health conditions. We propose that educational attainment, as a proxy for cognition, may increase with improved air quality. This study will explore whether asthma and seasonal allergic rhinitis, when exacerbated by acute exposure to air pollution, is associated with educational attainment. Objective To describe the preparation of individual and household-level linked environmental and health data for analysis within an anonymised safe haven. Also to introduce our statistical analysis plan for our study: COgnition, Respiratory Tract illness and Effects of eXposure (CORTEX). Methods We imported daily air pollution and aeroallergen data, and individual level education data into the SAIL databank, an anonymised safe haven for person-based records. We linked individual-level education, socioeconomic and health data to air quality data for home and school locations, creating tailored exposures for individuals across a city. We developed daily exposure data for all pupils in repeated cross sectional exam cohorts (2009-2015). Conclusion We have used the SAIL databank, an innovative, data safe haven to create individual-level exposures to air pollution and pollen for multiple daily home and school locations. The analysis platform will allow us to evaluate retrospectively the impact of air quality on attainment for multiple cross-sectional cohorts of pupils. Our methods will allow us to distinguish between the pollution impacts on educational attainment for pupils with and without respiratory health conditions. The results from this study will further our understanding of the effects of air quality and respiratory-related health conditions on cognition. Highlights This city-wide study includes longitudinal routinely-recorded educational attainment data for all pupils taking exams over seven years; High spatial resolution air pollution data were linked within a privacy protected databank to obtain individual exposure at multiple daily locations; This study will use health data linked at the individual level to explore associations between air pollution, related morbidity, and educational attainment.

Validating injury burden estimates using population birth cohorts and longitudinal cohort studies of injury outcomes: The VIBES-Junior study protocol

Introduction Traumatic injury is a leading contributor to the global disease burden in children and adolescents, but methods used to estimate burden do not account for differences in patterns of injury and recovery between children and adults. A lack of empirical data on postinjury disability in children has limited capacity to derive valid disability weights and describe the long-term individual and societal impacts of injury in the early part of life. The aim of this study is to establish valid estimates of the burden of non-fatal injury in children and adolescents. Methods and analysis Five longitudinal studies of paediatric injury survivors <18 years at the time of injury (Australia, Canada, UK and USA) and two whole-of-population linked administrative data paediatric studies (Australia and Wales) will be analysed over a 3-year period commencing 2018. Meta-analysis of deidentified patient-level data (n≈2,600) from five injury-specific longitudinal studies (Victorian State Trauma Registry; Victorian Orthopaedic Trauma Outcomes Registry; UK Burden of Injury; British Columbia Children’s Hospital Longitudinal Injury Outcomes; Children’s Health After Injury) and >1 million children from two whole-of-population cohorts (South Australian Early Childhood Data Project and Wales Electronic Cohort for Children). Systematic analysis of pooled injury-specific cohort data using a variety of statistical techniques, and parallel analysis of whole-of-population cohorts, will be used to develop estimated disability weights for years lost due to disability, establish appropriate injury classifications and explore factors influencing recovery. Ethics and dissemination The project was approved by the Monash University Human Research Ethics Committee project number 12 311. Results of this study will be submitted for publication in internationally peer-reviewed journals. The findings from this project have the capacity to improve the validity of paediatric injury burden measurements in future local and global burden of disease studies.

493 Cohort study of osteoporosis and fracture risk: are we achieving benefit with secondary prevention?

Background Osteoporosis is a global disease with a 30–40% lifetime risk of associated fractures according to the World Health Organisation. Osteoporosis incidence is likely to rise with ageing populations. Risk factor modification and medical treatments may reduce fracture risk. This work aimed to investigate the time to second fracture of patients receiving medical secondary prevention following index fracture compared to those that did not. Methods An observational study design involved the formation of an anonymised e-cohort utilising linked records. All low impact fractures in patients aged >60 years were identified from the Secure Anonymised Information Linkage database between 01/04/2009 and 31/12/2014. Index and secondary fractures were identified from the emergency department and inpatient data sets. Linkages were made to censor for migration and mortality. Linked primary care records identified patients that had received prescriptions for fracture prevention medications. Statistical analysis involved regression models with accelerated time adjustments. Results Over 49,000 cases were included. Of these, 8,033 (16.1%) had received medical treatment, the median age was 78 years (range 60–108) and 14,120 (28.4%) were male. Receiving medical treatment was significantly associated with increasing age (OR 1.02, 95% CI: 1.017–1.022, p < 0.001) and female gender (p < 0.001). Secondary prevention was significantly and independently associated with lower hazard of second fracture (HR 0.25, 95% CI: 0.15–0.41, p < 0.001). Conclusions Secondary medical prevention was associated with a 75% reduction in the hazard of sustaining a second fracture. However, fewer than a fifth of patients received such treatment. Study limitations include selection bias and potential residual confounding as patients were not randomised. Future work should focus on groups most likely to benefit from secondary prevention treatment to better inform clinical practice.