bluuebunny/crossref_metadata_2025 huggingface dataset:
COVID-19 vaccine coverage and factors associated with vaccine uptake among individuals with a recent experience of homelessness: a population-based analysis from Ontario, Canada.
Authors: Shariff Salimah , Richard Lucie , Hwang Stephen , Kwong Jeffrey , Forchuk Cheryl , Dosani Naheed , Booth Richard
Published: September 2022

ObjectivesTo describe COVID-19 vaccine coverage (i.e., the estimated percentage of people who have received a vaccine) and determinants of vaccine receipt among individuals with a recent experience of homelessness in Ontario, Canada.
ApproachWe conducted a retrospective, population-based cohort study of 23,247 individuals (≥18 years) with a recent experience of homelessness as recorded in routinely collected healthcare databases. Participants were followed from December 14, 2020 to September 30, 2021 for the receipt of a COVID-19 vaccine. Using modified Poisson regression, we identified sociodemographic, healthcare usage, and clinical factors associated with the receipt of one or more doses of a COVID-19 vaccine.
ResultsBy September 30, 14,271 (61.4%) of participants with a recent experience of homelessness had received a first dose of a COVID-19 vaccine and 11,082 (47.7%) had received two doses. Over the same period, 86.6% and 81.6% of the total adult population of Ontario had received a first dose and second dose, respectively. In multivariable analysis, factors associated with increased COVID-19 uptake included ≥1 visit to a general practitioner (adjusted Risk Ratio [aRR]:1.37[95% CI 1.31-1.42]), older age (vs. 18-29 years: 50-59 years, aRR:1.18[1.14-1.22]; 60+ years, aRR:1.27[1.22-1.31]), receipt of an influenza vaccine (aRR:1.25[1.23-1.28]), receipt of  ≥1 SARS-CoV-2 test (aRR:1.23[1.20-1.26]) and the presence of chronic health conditions (vs. 0 conditions: 1 condition, aRR:1.05[1.03, 1.08]; 2+ conditions, aRR:1.11[1.08-1.14]). In contrast, living in a smaller metropolitan region (aRR:0.92[0.90-0.94]) or rural location (aRR:0.93[0.90-0.97]) compared to a large metropolitan region was associated with lower uptake.
ConclusionsAs of September 30, 2021, COVID-19 vaccine coverage among individuals with a recent experience of homelessness in Ontario was substantially lower than the general adult population of Ontario for a first and second dose. Findings underscore the importance of leveraging organizations that are accessed and trusted by people who experience homelessness for targeted vaccine delivery.
Exposure to PM 2.5 and Birth Outcomes: Evidence from a Population-wide Database.
Authors: Rowland Neil , Jahanshahi Babak , McVicar Duncan , O'Reilly Dermot , McGovern Mark
Published: September 2022

This paper links localised annual average ambient air pollution data to a population database of births in Northern Ireland between 2011 and 2017 to investigate the relationship between particulate matter (PM) 2.5 exposure during pregnancy and a range of birth outcomes, with a focus on birth weight.
Linear regression analysis is used to estimate the effect of exposure to PM 2.5 during pregnancy on commonly studied markers of infant health (birth weight, preterm birth), less commonly studied markers such as Apgar scores, and markers of placental health which potentially represent a mechanism through which pollution might negatively affect newborns. In addition to maternal characteristics and weather conditions, detailed adjustment is made for area of residence. Moreover, comparisons of birth outcomes are drawn amongst siblings born at different times and subject to different levels of in utero exposure, permitting adjustment for mother-specific factors common to siblings.
Most birth outcomes exhibit a strong unadjusted association with PM 2.5 exposure that conforms with expectations. For birth weight, the negative effect of PM 2.5 weakens slightly after adjusting for differences in maternal characteristics and weather, but weakens much further after adjusting additionally for area of residence. After adjustment, being born to mothers in the middling (6-10 micrograms per cubic metre) and highest (10-16 micrograms per cubic metre) categories of exposure is associated with a 12 gram and 32 gram reduction in mean birth weight, respectively, compared to being born into the lowest (3-6 micrograms per cubic metre) category. However, after adjusting additionally for mother-specific factors, these effects become statistically no different from zero. This holds for other outcomes, including measures of placental health.
We find little evidence that exposure to PM 2.5 is related to worse infant health once we adjust as fully as possible for omitted variable bias. We conclude that the association between PM 2.5 and birth outcomes in this population at least partly reflects unmeasured characteristics of families.
How do infants enter and move through the care and family justice systems in Wales? Protocol for a population-based data linkage study.
Authors: Cowley Laura , North Laura , Broadhurst Karen , Doebler Stefanie , Cusworth Linda , Griffiths Lucy
Published: September 2022

ObjectivesWe aim to determine the proportion of infants entering care in Wales via the two primary legal routes (section 76 of the Social Services and Wellbeing (Wales) Act 2014, and section 31 of the Children Act 1989), and associations between mode of entry and infant characteristics and outcomes.
ApproachThis is a longitudinal cohort study using routinely collected data held in the Secure Anonymised Information Linkage (SAIL) Databank. We will link the Looked After Children dataset with family justice (Cafcass Cymru) data on section 31 proceedings, to explore pathways through the care and family justice systems for infants aged <1 year entering care in Wales between 2012 and 2019. We will follow up each child for two years from the date of their entry into care to track legal outcomes (final legal orders) and placement outcomes (placement type, number of placements, and re-entry into the care system).
ResultsDescriptive statistics will include frequencies and proportions of infants who initially enter the care system via voluntary arrangements (section 76) and care proceedings (section 31), by age, year, local authority, and category of need. We will describe the proportion and characteristics of those with voluntary arrangements who later become the subject of care proceedings, and the distribution of final legal orders and placement types by initial route of entry to care. We will use funnel plots to investigate variation between local authorities. We will use linear regression to test for statistically significant differences in the proportions of infants entering care via the two different routes over time, and chi-square tests to investigate associations between mode of entry and infant characteristics and outcomes.
ConclusionThere is limited information on the care journeys of children in Wales at the individual level. This study will help us to understand the patterns of use of voluntary arrangements for infants over time, the proportion subsequently involved in section 31 applications and the impact on outcomes for children.
Creating and Evaluating Two Cumulative Developmental Vulnerability Risk Measures.
Authors: Duku Eric , Pottruff Molly , Janus Magdalena
Published: September 2022

ObjectivesThe Early Development Instrument (EDI) is a valid and reliable population-level tool measuring child developmental vulnerability in Kindergarten. The objective of this study was to derive and validate new EDI-based development “cumulative vulnerability” risk indicators using a cumulative risk index approach (Rutter, 1979).
ApproachThe EDI has two main outcome measures: individual domain scores and vulnerability (scoring below a 10% cutpoint). To account for more complexity, we derived two new “cumulative vulnerability” measures. The Mean EDI Domain Score (MEDS) is the mean of the domain scores, and the Total EDI Vulnerability Index (TEVI) is an ordinal summative measure using domain vulnerability indicators. In Study I, we examined the relationship of the MEDS and TEVI measures with neighbourhood-level SES. In Study II, we examined the predictive/explanatory power of the MEDS and TEVI measures with Grade 3 provincial assessments in Ontario, Canada.
ResultsStudy I used EDI Kindergarten data from twelve provincial and territorial data collections between 2008 and 2013 in Canada (316,015 children) aggregated to 2,038 customized neighbourhoods. The two new cumulative vulnerability measures worked as expected, with positive association between MEDS and neighbourhood SES (r=0.58), and a negative association between TEVI and neighbourhood SES (r=-0.57). Study II used data from 61,039 Kindergarten children matched between the EDI and Grade 3 EQAO datasets. The predictive/explanatory power of Mean EDI Domain Scores (MEDS; R2=0.11 to 0.15) was twice that of new ordinal summative measure (TEVI; R2=0.06 to 0.08). Interestingly, the predictive power of the TEVI was similar to that of the composite EDI outcome measure, overall vulnerability (vulnerable on one or more domains).
ConclusionThe MEDS and TEVI work as expected and can be used for research and reporting purposes. More specifically, the TEVI can also be used as a severity metric evaluating the impact of multiple developmental vulnerabilities. It is recommended that further research be conducted to validate the measures with other datasets.
Is Long-Term Exposure to Ambient Air Pollution a Risk Factor for Parkinson’s Disease.
Authors: Jahanshahi Babak , McVicar Duncan , Rowland Neil , McGovern Mark , O'Reilly Dermot
Published: September 2022

ObjectivesThis paper links prescriptions data for the Northern Ireland population with data from the Northern Ireland Longitudinal Study and localized ambient air pollution data from 2002 onwards to estimate the association between long-term exposure to ambient air pollutant from fine particulates (PM2.5) and Parkinson’s Disease (PD).
ApproachCox Proportional Hazards models are used to examine the impact of air pollution on PD, first unconditionally, and then conditioning on a rich set of observable individual, family and contextual characteristics. Long-term exposure to PM2.5 is defined as exposure averaged over the previous 5 years. Onset of PD is proxied by first receipt of a prescription for PD medication.  Estimates are presented in the form of hazard ratios for the effect of long-term PM2.5 exposure on the risk of PD onset.
ResultsThere is a non-trivial magnitude and statistically significant unconditional association between long-term exposure to ambient PM2.5 pollution and receiving a prescription for PD, with those exposed to higher levels of pollution more likely to receive a prescription for PD. This estimated association disappears (becomes insignificantly different from zero), however, when the model accounts for confounding variables at household, individual and geographical levels.
ConclusionsThis study contributes to an emerging literature examining the association between ambient PM2.5 pollution and onset of PD. Despite finding an unconditional association, we find no evidence for an association once individual, family and contextual characteristics are controlled for, at least in the relatively low-pollution context of Northern Ireland.
What do women living with HIV think about research on children born HIV-free in the UK?
Authors: Bukasa Laurette , Namiba Angelina , Tariq Shema , Brown Matilda , Ndungu Estelle , Nangwale Mercy , Letting Gillian , Chirwa Patricia , Thorne Claire
Published: September 2022

ObjectiveWe are analysing linked public health surveillance data on pregnancies to women living with HIV in the UK and vital registration data on all their children born HIV-free, an under-researched group. We sought to engage women living with HIV to elicit their feedback on our work and set research priorities.
ApproachIn partnership with 4M Net, a national peer-support network for mothers living with HIV, we co-designed and held two online workshops (one workshop a week over two weeks) in March 2022.  We designed the workshops to be highly interactive, using a combination of online tools and created a safe space for open discussion. All participants received a preparatory booklet in advance, comprising questions, activities, and space for reflections during the workshops.  We also prompted participants to discuss their research priorities with peers and/or family members if they felt comfortable with this.
ResultsIn total, 6 participants attended the two 2-hour long workshops. All participants were from Black ethnic backgrounds, aged 30 years or older and were mothers of children or young adults born HIV-free.
Overall, participants were positive about the programme of research and identified pregnancy, birth, and long-term outcomes in children (especially regarding HIV medication in pregnancy) as being of key importance. They supported the use of linked mental health, hospital, general practice (GP), health visiting and education data to explore pregnancy, health and developmental outcomes among children born HIV-free. Linkage to GP data was identified as a priority by participants, and there was particular interest in addressing knowledge gaps on the mental health of children and young adults born HIV-free.
ConclusionWomen living with HIV are often involved in research around pregnancy, but rarely in research about their children. By working with trusted community partners, we can engage this often marginalised group of parents who understand the value of linked data research exploring the health and wellbeing of their children born HIV-free.
Are children living with obesity more likely to consult their general practitioner for knee pain? Longitudinal analysis of linked primary care and National Child Measurement Programme (NCMP) records.
Authors: Firman Nicola , Homer Kate , Harper Gill , Robson John , Dezateux Carol
Published: September 2022

ObjectivesMore than one in four 11-year-old children in England are living with obesity. The implications for future musculoskeletal health remain unclear. We assessed whether general practitioner consultations for knee pain were more likely among children with obesity, and how this varied by sex, ethnic background, and area-level deprivation.
ApproachOf 61,478 11-year-old NCMP participants (2013-19), we linked 60,723 (98.8%) to their primary care records. 58,761 children (50.9% male) had no recorded knee pain consultation (including arthralgia and Osgood-Schlatter’s disease) prior to the NCMP measurement date. We calculated the proportion with a consultation for knee pain by ethnic-adjusted weight status (underweight<2nd; overweight≥91st; obese≥98th centile), sex, ethnic background and Index of Multiple Deprivation quintile. We studied time to first general practitioner consultation for knee pain after the NCMP date by fitting Cox proportional hazards models, estimating mutually-adjusted hazard ratios (aHRs) and 95% confidence intervals (CI) for boys and girls separately.
ResultsWe identified 2503 (4.3%) children with at least one consultation for knee pain after the NCMP date. Boys were more likely to consult than girls (mean difference 1.5%; 95% CI: 1.2,1.9). Median time to first knee pain consultation was 1.88 years (IQR: 0.94,2.93). In adjusted analyses, boys with underweight (aHR 0.16; 95% CI: 0.05,0.51), from South Asian ethnic backgrounds (0.80; 0.69,0.92) and living in less deprived areas (Wald test statistic: 11.41; p-value=0.0223) were less likely, and those from Black ethnic backgrounds (1.31; 1.13,1.51) more likely, to consult with knee pain. Girls from South Asian ethnic backgrounds (0.70; 0.59,0.84) and those living in less deprived areas (15.44; p-value=0.0039) were less likely, and those with a BMI considered obese (1.30; 1.10,1.54) more likely to do so.
ConclusionAdolescent girls, but not boys, living with obesity are more likely to consult their general practitioner with knee pain. Ethnic differences in knee pain consultations merit further study. Linkage of primary care and NCMP records enables greater understanding of health service utilisation by children by weight status and demographic characteristics.
Evaluation of the real-world implementation of the Family Nurse Partnership in England: an observational cohort study using linked data from health, education and children’s social care.
Authors: Cavallaro Francesca , Kendall Sally , Van der Meulen Jan , Kennedy Eilis , Howarth Emma , Gilbert Ruth , Harron Katie
Published: September 2022

ObjectivesThe Family Nurse Partnership (FNP) is an early home visiting service supporting young mothers. A randomised controlled trial of FNP in England found no effect on short-term primary outcomes or maltreatment up to age seven, but positive impacts on educational outcomes by age 7. We report preliminary results of an evaluation of FNP using linked administrative data.
ApproachWe constructed a cohort of all mothers aged 13-19 and their firstborn child(ren) giving birth between 2010 and 2017, using linked administrative data from hospital admissions (Hospital Episode Statistics) and education and social care (National Pupil Database). We evaluated differences in a range of policy relevant child and maternal outcomes, comparing mothers who were enrolled in FNP with those who were not using propensity score matching.
ResultsOf 110,960 mothers in our linked cohort, 26,290 (24%) were enrolled in FNP. FNP mothers were younger, more deprived, and more likely to have adversity or social care histories than mothers not enrolled. Preliminary results suggest that FNP was not associated with fewer unplanned hospital admissions for injury / maltreatment by age two, improved child development at age 4, persistent school absence or children looked after in out-of-home care by age 7, or improved maternal outcomes. Some adverse outcomes appeared to be increased in the FNP group. We will present findings amongst subgroups of younger maternal age (13-15 years), increased deprivation according to quintile of Index of Multiple Deprivation, and adversity and social care history. We also present sensitivity analyses that aim to minimise confounding.
ConclusionOur study supports findings from previous trials of FNP showing little benefit for measured child and maternal outcomes. Interpretation of results needs careful consideration of the impact of residual confounding due to unmeasured or undisclosed factors (e.g. family violence) linked to targeting of FNP to higher risk mothers, and surveillance bias.
Outcomes for Māori clients in the Housing First programme in Aotearoa New Zealand.
Authors: Chun Saera , Ombler Jenny , Pehi Tiria
Published: September 2022

ObjectivesWe present the backgrounds and outcomes for formerly homeless Māori (indigenous to Aotearoa) clients of the first Housing First programme in Aotearoa New Zealand, delivered by The People’s Project in Kirikiriroa. We compare the result from the Housing First Māori clients to the non-Māori comparison group and the general population.
ApproachThe Integrated Data Infrastructure (IDI) is linked microdata administered by Tatauranga Aotearoa Statistics New Zealand. It enables a comprehensive picture of the life course and outcomes for people who have received an intervention such as Housing First. The People’s Project supplied a list of identifiers of the Housing First clients who were supported into permanent housing between 2014 and 2017. De-identified data from clients were linked to a central dataset in the IDI. We investigated service interaction histories, and up to four years post-housing outcomes across a broad range of datasets, including health, justice, social development, and income data.
ResultsComparing Māori clients to non-Māori demonstrated the existing systematic barriers that prevent access to services and result in worse outcomes for general Māori population also persist for the formerly homeless Māori. While all clients had higher service usage rates compared to the general population before being housed and continue to do so after being housed, Māori still faced barriers that their service usages rates were lower and outcomes were less favourable than non-Māori. This was especially visible in health datasets.
Māori clients have higher charge rates per offending on average. While victimisation rates increased for everyone after being housed, Māori clients were more likely to be crime victims. Income analysis showed that while Māori clients were employed at similar rates, they earned less than non-Māori.
ConclusionWe demonstrated that interventions like Housing First are positive, but when implemented within an inequitable system for certain populations, can be less effective for those populations. Programmes to address homelessness should be implemented in the context of wider systems change that addresses the root causes of inequities to be effective.
Does cycling to work benefit mental health? A natural experiment using linked administrative data.
Authors: Berrie Laurie , Feng Zhiqiang , Clemens Tom , Williamson Lee , Dibben Chris
Published: September 2022

ObjectivesWe spend an increasing part of our daily lives commuting. Observational studies have shown commuting by bicycle improves subjective well-being. This study uses a quasi-experimental approach and an objective measure of mental health taken from linked administrative data to ask “does cycling to work benefit mental health?”
ApproachPrevious studies have tended to use cross-sectional survey data which have small sample sizes and self-reported health measures that are subject to reporting bias. The potential for unmeasured confounding and reverse causation also weakens any conclusions. Our study links the Scottish population census with NHS Prescribing Information System records for data on commuting in Edinburgh and Glasgow and mental health prescriptions, respectively. Although there are complexities in determining causal effects from observational data, we employ an instrumental variable approach to address this using road distance from home to nearest cycle path as an instrument.
ResultsApproximately 400,000 people aged 16-74 living and working in the City of Edinburgh and Glasgow City council areas as at the 2011 census were included in our study. Of those, 1.85% of commuters in Glasgow and 4.8% of commuters in Edinburgh cycled to work. Amongst cyclists 9% had a prescription for mental health compared to 14% amongst non-cyclists. More than 50% of commutes in both cities are less than 5km. Using the instrumental variable in a bivariate probit model we estimate an average treatment effect of -16.1% (95% confidence interval: -15.1% to -17.1%) in mental health prescriptions amongst those who cycle to work compared to those who use other forms of transport.
ConclusionThis work confirms the benefit of cycling to work for mental health and provides further evidence in support of the promotion of active travel to encourage commuters travelling shorter distances to shift to cycling to work.
Towards a Scottish Safe Haven Federation.
Authors: Gao Chuang , Mayor Charlie , McCall Sophie , Wilde Katie , Cole Christian , Jefferson Emily
Published: September 2022

ObjectivesBuilding upon the Scottish Safe Haven Network’s (SSHN) collaborative experience to develop an exemplar dataset on Scottish national level laboratory tests within the SSHN. To test the feasibility of a federated safe haven network in Scotland for clinical laboratory data using existing federation solutions.
ApproachConsiderations were given to the clinical tests that are being commonly used across Scotland. An investigation of laboratory data structure was conducted using SQL with the assistance of White Rabbit which captures the metadata information from each safe haven. Data heterogeneity or commonalities were investigated in detail in R. We examined the inter-relationships among clinical laboratories from different regions of NHS Scotland. A common data structure was proposed to facilitate the sharing of clinical test results. We investigated multiple existing federation solutions to streamline access to data across the SSHN.
ResultsA dataset of all laboratory tests for patients registered with the Scottish Health Research Register and Biobank (SHARE) from laboratory data sources within the network (Grampian Data Safe Haven, Health Informatics Center, Glasgow Safe Haven & Lothian/DataLoch Safe Haven) were developed. An open-source toolkit that includes SQL scripts to harmonise laboratory data from multiple safe haven and R scripts to conduct heterogeneity investigation to streamline the sharing and the analysis was created. We have shown a working model for federation within Scotland for the first time with the view to expand into more routine projects. The project has developed a systematic concept mapping of data available across the SSHN to aid cohort discovery.
ConclusionsThe exemplar national level laboratory data together with the toolkit will help provide researchers with information such as which data are available to access. It will also support and improve national-level research studies at a faster pace. The work has demonstrated the feasibility of a common process for federated data discovery and sharing across the SSHN.
An investigation of kindergarten educator reported barriers and concerns and school neighbourhood composition in Ontario, Canada.
Authors: Spadafora Natalie , Reid-Westoby Caroline , Pottruff Molly , Wang Jade , Duku Eric , Janus Magdalena
Published: September 2022

ObjectivesThe COVID-19 pandemic has not impacted everyone equitably, including children (e.g., Li et al., 2021). The objective of this study was to explore the association between school neighbourhood composition and kindergarten educator-reported barriers and concerns regarding children’s learning during the first wave of COVID-19 related school closures in Ontario, Canada.
ApproachIn the spring of 2020, we collected data from Ontario kindergarten educators in an online survey on their experiences and challenges with online learning during the first round of school closures. We asked educators whether they experienced a number of barriers to learning and concerns about returning to school in the Fall. We linked the educator responses to 2016 Canadian Census variables based on the school postal code. Poisson regression analyses were used to determine if there was an association between neighbourhood composition and the number of barriers and concerns reported by kindergarten educators.
ResultsEducators (n = 2569; 74.2% kindergarten teachers, 25.8% early childhood educators; 97.6% female) who taught at schools in neighbourhoods with lower median income reported a greater number of barriers to online learning (e.g., students' lack of access to electronic devices) and concerns regarding the return to school in the fall of 2020 (e.g., concerned about differences in how much students learned during the school closures). Educators also reported a greater number of concerns regarding the return to the classroom in neighbourhoods with a greater proportion of single-parent families.
ConclusionOur study confirms that the educational impacts of the COVID-19 pandemic may not have been felt equitably even by kindergarten children, as educators teaching in schools in lower SES neighbourhoods reported both more barriers to online learning, and more concerns about returning to the classroom in September 2020.
Occupational differences in COVID-19 hospital admission and mortality between women and men in Scotland: A population-based study using linked administrative data.
Authors: Pattaro Serena , Bailey Nick , Dibben Chris
Published: September 2022

ObjectivesWe aim to estimate occupational differences in COVID-19 hospital admission and mortality by sex. Occupations vary with respect to environmental factors that influence exposure to COVID-19 such as ventilation, social contact and protective equipment. Variations between women and men may arise because they occupy different roles within an occupation or from behavioural differences.
ApproachWe established an innovative linked data collection combining individual-level data from 2011 Census with health administrative records and household identifiers from Ordnance Survey’s Unique Property Reference Number (UPRN). Using data for a cohort of approximately 1.7 million Scottish adults aged 40 to 64 years, we analysed occupational differences in COVID-19 hospital admission and mortality, during the period between 1 March 2020 and 31 January 2021. We estimated age-standardised incidence rates (ASIRs) for COVID-19 hospital admission and death per 100,000 adults, stratified by sex and occupation. Using Cox proportional hazards models, we estimated COVID-19 hospital admission and death risks, adjusting for socio-economic and pre-pandemic health factors.
ResultsGenerally, women had lower ASIRs for COVID-19 hospital admission and mortality compared to men. For COVID-19 mortality, ASIRs were highest among women employed in elementary trades and related occupations (e.g. packers/canners). For hospital admission, high rates were observed among women working in caring personal services (e.g. nursing assistants/ambulance staff). Among men, ASIRs were highest among those in elementary services occupations (kitchen assistants/waiters) and taxi drivers, who also had the highest admission rate. After adjusting for pre-pandemic health factors, we observed lower death risks for women employed as health professionals, and those in associate professional and technical occupations (medical technicians/paramedics), compared to the baseline model. Lower adjusted admission risks were also observed for both women and men in professional occupations (e.g. in science/engineering and teaching/education). Among men, adjusted death risks remained elevated for large vehicle and taxi drivers, who also displayed high admission risks.
ConclusionOccupational differences in COVID-19 hospital admission and mortality between women and men may be explained by a mixture of social, workplace and behavioural factors. These need to be considered when designing intervention policies which aim to reduce infections in the workplace.
Developing a population data science approach to assess increased risk of COVID-19 associated with attending large sporting events.
Authors: Drakesmith Mark , Hobson Gemma , John Gareth , Stegall Emily , Gould Ashley , Parkinson John , Thomas Daniel Rhys
Published: September 2022

ObjectivesTo design and test a method to assess whether test events were associated with an increase in risk of confirmed COVID-19, in order to inform policy on the safe re-introduction of spectator events following decreasing incidence of COVID-19 and relaxing of restrictions.
ApproachWe designed a cohort study to measure relative risk of confirmed COVID-19 in those attending two large sporting events in South Wales during May-June 2021. First, we linked ticketing information to records on the Welsh Demographic Service (WDS) and identified NHS numbers for attendees. We then linked attendees to routine SARS-CoV-2 test data to calculate incidence rates in people attending each event for a fourteen days period following the event.  We selected a comparison cohort from WDS for each event, individually matched by age band, gender and locality of residence. Risk ratios were then computed for the two events.
ResultsWe successfully assigned NHS numbers to 91% and 84% of people attending the two events, respectively. Other identifiers were available for the remainder. Only a small number of attendees (<10) had a record of confirmed COVID-19 following attendance at each event (14 day cumulative incidence: 36 and 26 per 100,000, respectively). Background incidences in Wales over the same periods were 22 and 61 per 100,000, respectively.  There was no evidence of significantly increased risk of COVID-19 at either event (event 1: 3.00 (0.18-47.9), p=0.50, event 2: 0.30 (0.04-2.34), p= 0.23). However, event 1, which didn’t include pre-event testing in their mitigations, had a higher risk ratio (>1) than event 2 (<1), which did include pre-event testing.
ConclusionsWe demonstrate the potential for data linkage to inform COVID-19 policy regarding sporting events. At that point in the epidemic, there was no evidence that attending large sporting events increased risk of COVID-19. However, these events took place between epidemic waves when background incidence and testing rate was low.
ClustEHR: a tool for generating synthetic EHR data for unsupervised learning experiments.
Authors: Alexander Nonie , Alexander Daniel , Denaxas Spiros
Published: September 2022

ObjectivesClustering algorithms are commonly used to identify disease clusters. New Clustering algorithms are benchmarked on synthetic data to assess their accuracy. These datasets lack the complexities of real electronic health record (EHR) producing a partial assessment of the algorithm. We developed a synthetic EHR cluster generator for benchmarking clustering algorithms.
ApproachWe have created a synthetic EHR cluster generator, clustEHR, based on Synthea, a synthetic EHR generator that produces datasets (with parameterized noise and cluster separation) of known clusters and with clinically relevant patient outcomes. We evaluated clustEHR by generating multiple datasets of variable cluster separation and percentage of noise variables to reflect easy and hard clustering problems. We used a linear model to assess the relationship between these parameters and cluster problem difficulty. K-means accuracy was used as a proxy to measure cluster problem difficulty.
ResultsWe have developed a tool for generating synthetic EHR cluster data with clinically relevant outcomes based on the rate of decline of medical observations (e.g. blood pressure). The following parameters are supported: a) number of clusters, b) number of patients in each cluster, c) number and data type of features, d) separation through defining clusters as either diseases such as COPD or dementia (high separability) or inter-disease conditions such as emphysema and chronic bronchitis within COPD (low separability), and e) noise variables through identifying variables not predictive of true cluster outcomes random forest feature importance metric. We show that high cluster separation significantly increases k-means accuracy (coefficient of 0.33). Smaller percent of noise variables increase accuracy though not significantly (coefficient 0.42).
ConclusionClustEHR offers realistic mixed data types as well as outcomes which are frequently used to evaluate clusters when subtyping diseases. The evaluating results suggest that the difficulty of the cluster data can be user determined. The tool can be used to create realistic datasets for evaluating clustering approaches.
Making the 2022 Rwanda Census count.
Authors: Shipsey Rachel
Published: September 2022

For the 2022 Rwanda Census, data will be collected electronically for the first time. This provides both an opportunity and a challenge to use technology for census processing. We are working with National Institute of Statistics Rwanda (NISR) to help overcome linkage problems and produce robust population estimates.
Working with NISR we aim to create an achievable Census solution given the constraints on time, computing power and experience. We identified key issues, such as the lack of addresses and full date of birth, and developed a series of recommendations. These combined our experience of census processing and NISR’s knowledge of Rwandan geography, conventions and culture to develop the simplest solutions possible, ensuring that each recommendation gave maximum benefit for the effort required. Next, we plan to use 2021 Rwanda Census Pilot data to begin development of an end-to-end matching exercise including pre-processing, automatic linkage, clerical resolution and quality assurance.
We developed recommendations, including small changes to the data collection application and creating a Unique Property Reference Number by concatenating the Enumeration Area code and the Structure Number written on the building during Census collection. Following this, we produced a synthetic Rwandan Census and Post Enumeration Survey (PES) which was used to demonstrate and collaboratively develop matching algorithms. Probabilistic linkage methods were considered but discarded due to lack of sufficient infrastructure. Instead, deterministic methods were used. Match keys are currently being developed by NISR with clerical review undertaken using our open-source Clerical Matching Online Widget (CROW) with the synthetic data. Future plans include using the Census Pilot to estimate overcount and developing a modified version of the Soundex phonetic encoder for use on Rwandan names.
The resource available for the Rwandan Census is comparatively small, but even the smallest resource can have a massive impact when used productively. This collaborative project takes the key concepts of well-developed linkage strategy and makes appropriate modifications to enable an achievable and effective Rwandan Census linkage strategy.
Microsimulation of an educational attainment register to study record linkage quality.
Authors: Schnell Rainer , Weiand Severin
Published: September 2022

Population covering educational attainment registers have been proven helpful for planning and research concerning educational efforts. Regular linking of different databases is needed to build and update such a register. Without unique national identification numbers, record linkage must be based on quasi-identifiers such as names, date of birth and sex. High-quality record linkage require the unique identification of persons. Therefore, available identifiers should be sufficient for unique identification despite missing identifiers for some cases. Redundant identifiers can achieve this goal. However, the data protection principle of data minimization, as recommended in the European General Data Protection Regulation, aims to avoid additional data if possible for the given purpose. Therefore, a ministry commissioned a simulation study to inform legislators on the minimum set of identifiers needed for a national register. A microsimulation of the population consisting of nearly 20 million people was implemented to generate data on accumulating changes and errors in identifiers over ten simulated years. The simulation covered, for example, international migration, regional mobility, marriages, school careers and mortality. Each event triggered changes of identifiers according to specified error probability models. The resulting data were linked by different record-linkage procedures. Linkage quality and linkage bias dependent on the available identifiers were assessed. We report on the design of the simulation study, the linkage results and recommendations for the minimum set of identifiers. The results may be helpful for the design of other population covering registers.
Impact of the Choosing Wisely Canada recommendations on potentially inappropriate antibiotic prescribing in emergency medicine across Alberta, Canada: An interrupted time-series analysis.
Authors: Black Jason , Campbell David , McBrien Kerry , Ronksley Paul , Lang Eddy , Williamson Tyler
Published: September 2022

ObjectivesIn Alberta, Canada, we quantified the rate of potentially inappropriate oral antibiotic prescribing in emergency departments for viral infections or conditions not likely requiring antibiotics from 2010-2020 and assessed the impact of two Choosing Wisely Canada (CWC) campaigns (2015/2016 and 2018) discouraging inappropriate antibiotic prescribing in emergency medicine.
ApproachWe linked emergency department adult and pediatric records from the National Ambulatory Care Reporting System and medication dispensations from community-based pharmacies in the Pharmaceutical Information Network. From January 2010 to February 2020, we identified emergency department visits for 5 conditions that were potentially inappropriately treated using antibiotics per CWC recommendations (bronchitis, asthma, bronchiolitis, pharyngitis, and acute otitis media). We used an interrupted time series design to detect changes in antibiotic prescribing by fitting Autoregressive Integrated Moving Average (ARIMA) models to account for secular trends and seasonality, allowing for change in slopes to measure the effect of each CWC intervention.
ResultsAntibiotics were commonly prescribed in emergency departments for bronchitis (proportion of visits with antibiotics: 57%) and asthma (22%) in adults; bronchiolitis in children (43%); pharyngitis (39%) and acute otitis media (54%) in adults and children. Based on visual inspection, the proportion of emergency department visits for each condition where antibiotics were dispensed remained relatively consistent. The ARIMA models demonstrated mixed impacts on potentially inappropriate antibiotic prescribing associated with two interruptions: the 2015/2016 CWC recommendations and subsequent 2018 CWC Using Antibiotics Wisely campaign. Following each interruption, antibiotic prescribing was slightly reduced for bronchitis (-1.0%/year,p=0.03; -4.4%/year,p=0.004, respectively) and bronchiolitis (not significant) (-0.7%/year,p=0.57; -2.5%/year,p=0.34), but unchanged for asthma (-0.6%/year,p=0.30; 0.7%/year,p=0.74) and pharyngitis (0.0%/year,p=0.95; -0.2%/year,p=0.93), and slightly increased for acute otitis media (not significant) (1.4%/year,p=0.07; 5.9%/year,p=0.052).
ConclusionRates of potentially inappropriate antibiotic prescribing remained constant over the past 10 years in Alberta. Campaigns to rethink antibiotic use in emergency medicine may have resulted in small decreases in antibiotic use; however, further initiatives building upon existing campaigns are required to substantially reduce rates of inappropriate antibiotic prescribing.
Developmental disability among Aboriginal children in Western Australia (WA).
Authors: Gibberd Alison , Eades Sandra , Psilos Nicoletta , Bourke Jenny , Leonard Helen , Carlin Emma , Kavanagh Anne , Walker Roz , O'Donnell Melissa , Colbung Rebecca , Nelson Lesley
Published: September 2022

BackgroundWhile Aboriginal Australians are known to be disproportionately affected by intellectual disabilities (ID) and/or autism spectrum disorders (developmental disabilities), true prevalences among Aboriginal children are unclear, with evidence of delayed and missed diagnoses and barriers to services. This study estimated these prevalences and disability service use among WA Aboriginal children.
ApproachTwo cohorts and data sources were used. Firstly, a state-based health and disability data linkage for all WA Aboriginal children born 2000-2013, including hospital, public outpatient mental health, birth and death data and state registries of birth defects, cerebral palsy and ID. The cumulative incidence of diagnosis by age 18 was estimated. Secondly, prevalence of service access was estimated from all National Disability Insurance Scheme (NDIS) WA Aboriginal and non-Aboriginal participants aged 0-17 on 30/6/2021 with a primary diagnosis of ID (with or without fetal alcohol spectrum disorder (FASD)) or autism. Census population counts were denominators.
ResultsUsing the data linkage, 3.3% of Aboriginal children born 2000-2013 were diagnosed with developmental disability by 18 years. The most common diagnosis (2.5%) was ID without FASD. Using NDIS data, 3.1% of Aboriginal children were NDIS participants with development disability in 2021, but only 0.7% of children with ID without FASD. Instead, autism was most common diagnosis. Aboriginal children were more likely than non-Aboriginal children to be NDIS participants with autism (prevalence ratio (PR): 1.16, 95% confidence interval (CI): 1.06-1.26), ID without FASD (PR: 2.06, 95% CI: 1.80-2.35) and ID with FASD (PR: 40.5, 95%CI: 29.9-57.1). For both data sources, prevalences differed by region. Aboriginal NDIS participants with ID had an older age distribution than non-Aboriginal participants.
ConclusionFor both cohorts, the prevalence of developmental disability was >3%, though the contributions of ID and autism differed in the two data sources. Variation in diagnoses by region and Aboriginal status may indicate differential diagnosis and variation in age suggests delayed diagnoses or access to services for Aboriginal children.
The hospital burden of intergenerational contact with the welfare system: A whole-of-population liked data study.
Authors: Procter Alexandra , Chittleborough Catherine , Pilkington Rhiannon , Pearson Odette , Montgomerie Alicia , Lynch John
Published: September 2022

ObjectivesIntergenerational welfare contact (IWC) is a policy issue due to personal and social costs of ‘entrenched disadvantage’ across generations, yet few studies have quantified the burden of IWC on health. We examine the proportion of children who experienced IWC and other welfare contact (WC) types; and estimate cause-specific hospital burden.
ApproachA whole-of-population linked administrative data study of children in South Australia born 1991-1995 (n=94,358), followed from birth up to age 20 years and their parent/s (n=143,814). The study used de-identified data from the Better Evidence Better Outcomes Linked Data platform including data from Australian Government Centrelink (welfare payments), birth registration, perinatal birth records, and inpatient hospitalisations. Children were classified as: No WC, parent only WC, child only WC, or IWC. Cause-specific hospitalisation rates and cumulative incidence were estimated by age and WC group.
ResultsUsing Australian Government Centrelink data, WC was defined as parent/s receiving a means-tested welfare payment (low-income, unemployment, disability or caring) when children were aged 11-15, or children receiving payment at ages 16-20. IWC was WC occurring in both parent and child generations. IWC affected 34.9% of children, who had the highest hospitalisation rate (133.5 per 1,000 person-years) compared to no WC (46.1 per 1,000 person-years), parent WC  (75.0 per 1,000 person-years), and child only WC (87.6 per 1,000 person-years). Of all IWC children, 43.0% experienced at least one hospitalisation between 11-20 years, frequently related to injury, mental health, and pregnancy.
Conclusions and RelevanceChildren experiencing IWC represent a third of the population aged 11-20. Compared to children with parent-only WC, IWC children had 78% higher hospitalisation rates from age 11 to 20, accounting for over half of all hospitalisations in this age group. Frequent IWC hospitalisation causes were injuries, mental health, and pregnancy.