Australian arm of the International Spinal Cord Injury (Aus-InSCI) community survey: 1. population-based design, methodology and cohort profile.

STUDY DESIGN: Cross-sectional survey. OBJECTIVES: To describe design and methods of Australian arm of International Spinal Cord Injury (Aus-InSCI) community survey, reporting on participation rates, potential non-response bias and cohort characteristics. SETTING: Survey of community-dwelling people with SCI at least 12 months post-injury, recruited between March 2018 and January 2019, from state-wide SCI services, a government insurance agency and not-for-profit consumer organisations across four Australian states. METHODS: The Aus-InSCI survey combined data for people with SCI from nine custodians, using secure data-linkage processes, to create a population-based, anonymised dataset. The Aus-InSCI questionnaire comprised 193 questions. Eligibility, response status and participation rates were calculated. Descriptive statistics depict participant characteristics. Logistic regression models were developed for probability of participation, and inverse probability weights generated to assess potential non-response bias. RESULTS: 1579 adults with SCI were recruited, a cooperation rate of 29.4%. Participants were predominantly male (73%), with 50% married. Mean age was 57 years (range 19-94) and average time post-injury 17 years (range 1-73). Paraplegia (61%) and incomplete lesions (68%) were most common. Males were more likely than females to have traumatic injuries (p < 0.0001) and complete lesions (p = 0.0002), and younger age-groups were more likely to have traumatic injuries and tetraplegia (p < 0.0001). Potential non-response bias evaluated using selected outcomes was found to be negligible in the Aus-InSCI cohort. CONCLUSIONS: The Aus-InSCI survey made efforts to maximise coverage, avoid recruitment bias and address non-response bias. The distributed, linked and coded (re-identifiable at each custodian level) 'virtual quasi-registry' data model supports systematic cross-sectional and longitudinal research.

A blinded evaluation of privacy preserving record linkage with Bloom filters.

BACKGROUND: Privacy preserving record linkage (PPRL) methods using Bloom filters have shown promise for use in operational linkage settings. However real-world evaluations are required to confirm their suitability in practice. METHODS: An extract of records from the Western Australian (WA) Hospital Morbidity Data Collection 2011-2015 and WA Death Registrations 2011-2015 were encoded to Bloom filters, and then linked using privacy-preserving methods. Results were compared to a traditional, un-encoded linkage of the same datasets using the same blocking criteria to enable direct investigation of the comparison step. The encoded linkage was carried out in a blinded setting, where there was no access to un-encoded data or a 'truth set'. RESULTS: The PPRL method using Bloom filters provided similar linkage quality to the traditional un-encoded linkage, with 99.3% of 'groupings' identical between privacy preserving and clear-text linkage. CONCLUSION: The Bloom filter method appears suitable for use in situations where clear-text identifiers cannot be provided for linkage.

A comparison of trajectories of offending among people with psychotic disorders, other mental disorders and no mental disorders: Evidence from a whole-of-population birth cohort study.

BACKGROUND: Trajectory analysis has been used to study long-term offending patterns and identify offender subgroups, but few such studies have included people with psychotic disorders (PDs) and these have been restricted to adult offenders. AIMS: To compare offending trajectories among 10-26-year-olds with PDs with those with other mental disorders (OMDs) or none (NMD) and identify associated risk factors. METHODS: This is a record-linkage study of 184,147 people born in Western Australia (WA) 1983-1991, drawing on data from WA mental health information system, WA corrective services and other state-wide registers. Group-based trajectory modelling was used to identify offending trajectories. RESULTS: Four offender groups were identified in each mental health status group: G1-no/negligible offending; G2-early onset, adolescent, desisting by age 18; G3-early onset, low rate, offending into early adulthood; and G4-very early onset, high rate, peaking at age 17, continuing into early adulthood. The PDs group had the lowest proportion of individuals with no or negligible offending histories-84% compared with 88.5% in the OMDs group and 96.6% in the no mental disorder group. Within mental health status offender groups, the PDs group was characterised by early or very early onset offending persisting into adulthood, accounting for 5.4% and 3.7% of the group respectively (OMD: 3.8%, 1.5%; NMD: 1.0%, 0.5%). Gender, indigenous status, substance use problems, childhood abuse and parental offending were generally associated with trajectory group membership, although among those with PDs childhood abuse and parental offending were only significant in the early onset-life-course-persistent group. CONCLUSIONS: While most people with PDs never offend, some are disproportionately vulnerable from a particularly early age. If the offending subgroup is to be helped away from criminal justice involvement, interventions must be considered in childhood.

Assessing the Risk of Australian Indigenous Sexual Offenders Reoffending: A Review of the Research Literature and Court Decisions.

The assessment of offenders' risk of reoffending, particularly sexual reoffending, is a core activity of forensic mental health practitioners. The purpose of these assessments is to reduce the risk of harm to the public, but they are controversial and become more contentious when Australian practitioners who want to undertake such assessments in an ethically responsible way must use reliable validated instruments, disclose the limitations of their assessment methods, instruments and data to judicial decision-makers and understand how decision-makers might use their reports. The purpose of this systematic literature review was to explore the practices of Australian practitioners and courts in respect of the assessment of Australian Indigenous male sexual offenders' risk of reoffending. We could not identify an instrument that has been developed for the assessment of this population group. Australian courts differ in whether they admit and give weight to practitioners' evidence and opinions based on data obtained with non-validated instruments. We could only identify three possible predictor variables with enough quantitative support to justify including them in an instrument that could be used to assess Indigenous sexual offenders. There is a need for research regarding the validity of the instruments that practitioners use.

The Effect of Vasectomy Reversal on Prostate Cancer Risk: International Meta-Analysis of 684,660 Vasectomized Men.

PURPOSE: Evidence of the effect of vasectomy on prostate cancer is conflicting with the issue of detection bias a key criticism. We examined the effect of vasectomy reversal on prostate cancer risk in a cohort of vasectomized men. Evidence of a protective effect would be consistent with a harmful effect of vasectomy on prostate cancer risk while nullifying the issue of detection bias. MATERIALS AND METHODS: Data were sourced from a total of 5 population level linked health databases in Australia, Canada and the United Kingdom. Cox proportional hazards regression analysis was used to compare the risk of prostate cancer in 9,754 men with vasectomy reversal to the risk in 684,660 with vasectomy but no reversal. Data from each jurisdiction were combined in a meta-analysis. RESULTS: The combined analysis showed no protective effect of vasectomy reversal on the incidence of prostate cancer compared to that in men with vasectomy alone (HR 0.92, 95% CI 0.70-1.21). CONCLUSIONS: These results align with those of previous studies showing no evidence of a link between vasectomy and prostate cancer.

Sociodemographic differences in linkage error: an examination of four large-scale datasets.

BACKGROUND: Record linkage is an important tool for epidemiologists and health planners. Record linkage studies will generally contain some level of residual record linkage error, where individual records are either incorrectly marked as belonging to the same individual, or incorrectly marked as belonging to separate individuals. A key question is whether errors in linkage quality are distributed evenly throughout the population, or whether certain subgroups will exhibit higher rates of error. Previous investigations of this issue have typically compared linked and un-linked records, which can conflate bias caused by record linkage error, with bias caused by missing records (data capture errors). METHODS: Four large administrative datasets were individually de-duplicated, with results compared to an available 'gold-standard' benchmark, allowing us to avoid methodological issues with comparing linked and un-linked records. Results were compared by gender, age, geographic remoteness (major cities, regional or remote) and socioeconomic status. RESULTS: Results varied between datasets, and by sociodemographic characteristic. The most consistent findings were worse linkage quality for younger individuals (seen in all four datasets) and worse linkage quality for those living in remote areas (seen in three of four datasets). The linkage quality within sociodemographic categories varied between datasets, with the associations with linkage error reversed across different datasets due to quirks of the specific data collection mechanisms and data sharing practices. CONCLUSIONS: These results suggest caution should be taken both when linking younger individuals and those in remote areas, and when analysing linked data from these subgroups. Further research is required to determine the ramifications of worse linkage quality in these subpopulations on research outcomes.

Estimating parameters for probabilistic linkage of privacy-preserved datasets.

BACKGROUND: Probabilistic record linkage is a process used to bring together person-based records from within the same dataset (de-duplication) or from disparate datasets using pairwise comparisons and matching probabilities. The linkage strategy and associated match probabilities are often estimated through investigations into data quality and manual inspection. However, as privacy-preserved datasets comprise encrypted data, such methods are not possible. In this paper, we present a method for estimating the probabilities and threshold values for probabilistic privacy-preserved record linkage using Bloom filters. METHODS: Our method was tested through a simulation study using synthetic data, followed by an application using real-world administrative data. Synthetic datasets were generated with error rates from zero to 20% error. Our method was used to estimate parameters (probabilities and thresholds) for de-duplication linkages. Linkage quality was determined by F-measure. Each dataset was privacy-preserved using separate Bloom filters for each field. Match probabilities were estimated using the expectation-maximisation (EM) algorithm on the privacy-preserved data. Threshold cut-off values were determined by an extension to the EM algorithm allowing linkage quality to be estimated for each possible threshold. De-duplication linkages of each privacy-preserved dataset were performed using both estimated and calculated probabilities. Linkage quality using the F-measure at the estimated threshold values was also compared to the highest F-measure. Three large administrative datasets were used to demonstrate the applicability of the probability and threshold estimation technique on real-world data. RESULTS: Linkage of the synthetic datasets using the estimated probabilities produced an F-measure that was comparable to the F-measure using calculated probabilities, even with up to 20% error. Linkage of the administrative datasets using estimated probabilities produced an F-measure that was higher than the F-measure using calculated probabilities. Further, the threshold estimation yielded results for F-measure that were only slightly below the highest possible for those probabilities. CONCLUSIONS: The method appears highly accurate across a spectrum of datasets with varying degrees of error. As there are few alternatives for parameter estimation, the approach is a major step towards providing a complete operational approach for probabilistic linkage of privacy-preserved datasets.

Cross border hospital use: analysis using data linkage across four Australian states.

OBJECTIVE: To determine the quality and effectiveness of national data linkage capacity by performing a proof-of-concept project investigating cross-border hospital use and hospital-related deaths. DESIGN, PARTICIPANTS AND SETTING: Analysis of person-level linked hospital separation and death registration data of all public and private hospital patients in New South Wales, Queensland and Western Australia and of public hospital patients in South Australia, totalling 7.7 million hospital patients from 1 July 2004 to 30 June 2009. MAIN OUTCOME MEASURES: Counts and proportions of hospital stays and patient movement patterns. RESULTS: 223 262 patients (3.0%) travelled across a state border to attend hospitals, in particular, far northern and western NSW patients travelling to Queensland and SA hospitals, respectively. A further 48 575 patients (0.6%) moved their place of residence interstate between hospital visits, particularly to and from areas associated with major mining and tourism industries. Over 11 000 cross-border hospital transfers were also identified. Of patients who travelled across a state border to hospital, 2800 (1.3%) died in that hospital. An additional 496 deaths recorded in one jurisdiction occurred within 30 days of hospital separation from another jurisdiction. CONCLUSIONS: Access to person-level data linked across jurisdictions identified geographical hot spots of cross-border hospital use and hospital-related deaths in Australia. This has implications for planning of health service delivery and for longitudinal follow-up studies, particularly those involving mobile populations.

Accuracy and completeness of patient pathways--the benefits of national data linkage in Australia.

BACKGROUND: The technical challenges associated with national data linkage, and the extent of cross-border population movements, are explored as part of a pioneering research project. The project involved linking state-based hospital admission records and death registrations across Australia for a national study of hospital related deaths. METHODS: The project linked over 44 million morbidity and mortality records from four Australian states between 1st July 1999 and 31st December 2009 using probabilistic methods. The accuracy of the linkage was measured through a comparison with jurisdictional keys sourced from individual states. The extent of cross-border population movement between these states was also assessed. RESULTS: Data matching identified almost twelve million individuals across the four Australian states. The percentage of individuals from one state with records found in another ranged from 3-5%. Using jurisdictional keys to measure linkage quality, results indicate a high matching efficiency (F measure 97 to 99%), with linkage processing taking only a matter of days. CONCLUSIONS: The results demonstrate the feasibility and accuracy of undertaking cross jurisdictional linkage for national research. The benefits are substantial, particularly in relation to capturing the full complement of records in patient pathways as a result of cross-border population movements. The project identified a sizeable 'mobile' population with hospital records in more than one state. Research studies that focus on a single jurisdiction will under-enumerate the extent of hospital usage by individuals in the population. It is important that researchers understand and are aware of the impact of this missing hospital activity on their studies. The project highlights the need for an efficient and accurate data linkage system to support national research across Australia.

Privacy-preserving record linkage on large real world datasets.

Record linkage typically involves the use of dedicated linkage units who are supplied with personally identifying information to determine individuals from within and across datasets. The personally identifying information supplied to linkage units is separated from clinical information prior to release by data custodians. While this substantially reduces the risk of disclosure of sensitive information, some residual risks still exist and remain a concern for some custodians. In this paper we trial a method of record linkage which reduces privacy risk still further on large real world administrative data. The method uses encrypted personal identifying information (bloom filters) in a probability-based linkage framework. The privacy preserving linkage method was tested on ten years of New South Wales (NSW) and Western Australian (WA) hospital admissions data, comprising in total over 26 million records. No difference in linkage quality was found when the results were compared to traditional probabilistic methods using full unencrypted personal identifiers. This presents as a possible means of reducing privacy risks related to record linkage in population level research studies. It is hoped that through adaptations of this method or similar privacy preserving methods, risks related to information disclosure can be reduced so that the benefits of linked research taking place can be fully realised.

Pain therapy, pediatric palliative care and end-of-life care: training, experience, and reactions of pediatric residents in Italy.

UNLABELLED: Pediatric palliative care represents the ideal response to life-limiting and life-threatening diseases and requires a specific and multidisciplinary training. This study aims at evaluating in Italy the training programs offered in pain therapy and pediatric palliative care, the exposure, and the personal experience concerning end-of-life care management. The data have been obtained through a survey addressed to all the residents specializing in pediatrics in Italy. Three hundred forty-eight of 1,200 residents from 33 of the 41 schools of pediatrics existing in Italy responded to the questionnaire. One hundred seventy-four of them (50 %) declared they received training in end-of-life care at least once: 146 during their graduation course of medicine, 84 during the pediatric residency, and 54 in both occasions. Sixty percent of respondents were present at one death at least, with an increasing percentage in the last years of residency (91.5 % in the fifth year) but only 12 % were directly involved in the management (36.2 % in the fifth year); 5.7 % managed at least one communication of death; 12.6 % followed sedo-analgesia protocols. Only 11 % of residents felt ready to face end-of-life care management. CONCLUSION: The training in end-of-life care in Italy is not currently satisfactory. Further efforts are therefore required to create a comprehensive and multidisciplinary training.

Technical challenges of providing record linkage services for research.

BACKGROUND: Record linkage techniques are widely used to enable health researchers to gain event based longitudinal information for entire populations. The task of record linkage is increasingly being undertaken by specialised linkage units (SLUs). In addition to the complexity of undertaking probabilistic record linkage, these units face additional technical challenges in providing record linkage 'as a service' for research. The extent of this functionality, and approaches to solving these issues, has had little focus in the record linkage literature. Few, if any, of the record linkage packages or systems currently used by SLUs include the full range of functions required. METHODS: This paper identifies and discusses some of the functions that are required or undertaken by SLUs in the provision of record linkage services. These include managing routine, on-going linkage; storing and handling changing data; handling different linkage scenarios; accommodating ever increasing datasets. Automated linkage processes are one way of ensuring consistency of results and scalability of service. RESULTS: Alternative solutions to some of these challenges are presented. By maintaining a full history of links, and storing pairwise information, many of the challenges around handling 'open' records, and providing automated managed extractions are solved. A number of these solutions were implemented as part of the development of the National Linkage System (NLS) by the Centre for Data Linkage (part of the Population Health Research Network) in Australia. CONCLUSIONS: The demand for, and complexity of, linkage services is growing. This presents as a challenge to SLUs as they seek to service the varying needs of dozens of research projects annually. Linkage units need to be both flexible and scalable to meet this demand. It is hoped the solutions presented here can help mitigate these difficulties.

Trajectories of homelessness and association with mental health and substance use disorders among young people transitioning from out-of-home care in Australia.

BACKGROUND: Researchers have examined sub-groups that may exist among young people transitioning from out-of-home care (OHC) using various theoretical models. However, this population group has not been examined for trajectories of homelessness risk. OBJECTIVES: To examine whether different subtypes of homelessness risk exist among young people transitioning from care and whether these trajectories of homelessness are associated with mental health and substance use disorders. PARTICIPANTS AND SETTING: A retrospective population-based cohort study was conducted from a population of 1018 young people (aged 15-18 years) who transitioned from out-of-home in 2013 to 2014 in the state of Victoria, Australia, with follow-up to 2018. METHODS: Latent Class Growth Analysis was conducted using linked data from homelessness data collections, child protection, mental health information systems, alcohol and drug use, and youth justice information systems. RESULTS: Three sub-groups of young people were identified. The 'moving on' group (88 %) had the lowest levels of homelessness, with the slope of this trajectory remaining almost stable. The 'survivors' (7 %) group started off with a high risk of homelessness, followed by a sharp decrease in homelessness risk over time. The 'complex' (5 %) group started off with a low risk of homelessness but faced sharp increases in the risk of homelessness over time. CONCLUSIONS: Our study demonstrates that subgroups of young people transitioning from care exist with distinct longitudinal trajectories of homelessness, and these classes are associated with different risk factors. Early intervention and different approaches to tackling homelessness should be considered for these three distinct groups before transitioning from care and during the first few years after leaving care.

Correction: Research using population-based administration data integrated with longitudinal data in child protection settings: A systematic review.

[This corrects the article DOI: 10.1371/journal.pone.0249088.].

An evaluation framework for comparing geocoding systems.

BACKGROUND: Geocoding, the process of converting textual information describing a location into one or more digital geographic representations, is a routine task performed at large organizations and government agencies across the globe. In a health context, this task is often a fundamental first step performed prior to all operations that take place in a spatially-based health study. As such, the quality of the geocoding system used within these agencies is of paramount concern to the agency (the producer) and researchers or policy-makers who wish to use these data (consumers). However, geocoding systems are continually evolving with new products coming on the market continuously. Agencies must develop and use criteria across a number axes when faced with decisions about building, buying, or maintaining any particular geocoding systems. To date, published criteria have focused on one or more aspects of geocode quality without taking a holistic view of a geocoding system's role within a large organization. The primary purpose of this study is to develop and test an evaluation framework to assist a large organization in determining which geocoding systems will meet its operational needs. METHODS: A geocoding platform evaluation framework is derived through an examination of prior literature on geocoding accuracy. The framework developed extends commonly used geocoding metrics to take into account the specific concerns of large organizations for which geocoding is a fundamental operational capability tightly-knit into its core mission of processing health data records. A case study is performed to evaluate the strengths and weaknesses of five geocoding platforms currently available in the Australian geospatial marketplace. RESULTS: The evaluation framework developed in this research is proven successful in differentiating between key capabilities of geocoding systems that are important in the context of a large organization with significant investments in geocoding resources. Results from the proposed methodology highlight important differences across all axes of geocoding system comparisons including spatial data output accuracy, reference data coverage, system flexibility, the potential for tight integration, and the need for specialized staff and/or development time and funding. Such results can empower decisions-makers within large organizations as they make decisions and investments in geocoding systems.

The effect of data cleaning on record linkage quality.

BACKGROUND: Within the field of record linkage, numerous data cleaning and standardisation techniques are employed to ensure the highest quality of links. While these facilities are common in record linkage software packages and are regularly deployed across record linkage units, little work has been published demonstrating the impact of data cleaning on linkage quality. METHODS: A range of cleaning techniques was applied to both a synthetically generated dataset and a large administrative dataset previously linked to a high standard. The effect of these changes on linkage quality was investigated using pairwise F-measure to determine quality. RESULTS: Data cleaning made little difference to the overall linkage quality, with heavy cleaning leading to a decrease in quality. Further examination showed that decreases in linkage quality were due to cleaning techniques typically reducing the variability - although correct records were now more likely to match, incorrect records were also more likely to match, and these incorrect matches outweighed the correct matches, reducing quality overall. CONCLUSIONS: Data cleaning techniques have minimal effect on linkage quality. Care should be taken during the data cleaning process.

Relationship between residential aged care facility characteristics and breaches of the Australian aged care regulatory standards: non-compliance notices and sanctions.

OBJECTIVES: To examine the relationship between structural characteristics of Australian residential aged care facilities (RACFs) and breaches of the aged care quality standards. METHODS: Facility-level analysis of audits, sanctions and non-compliance notices of all accredited Australian RACFs between 2015/16 and 2018/19. Structural factors of interest included RACF size, remoteness, ownership type and jurisdiction. Two government data sources were joined. Each outcome was analysed to calculate time trends, unadjusted rates and relative risks. RESULTS: Non-compliance notices were imposed on 369 RACFs (13%) and 83 sanctions on 75 RACFs (3%). Compared with New South Wales (NSW), non-compliance notices were less likely in Victoria, Queensland and the Northern Territory (NT), more likely in South Australia (SA), and comparable in Western Australia (WA), Tasmania and the Australian Capital Territory (ACT). RACFs with more than 100 beds and RACFs located in remote and outer regional areas (vs. major cities) also increased the likelihood of non-compliance notices. Compared with NSW, sanctions were less likely in Victoria, Queensland, NT and WA and comparable in SA, Tasmania and ACT. Additionally, the likelihood of sanctions was higher for RACFs with more than 40 beds. For both non-compliance notices and sanctions, no significant relationship was found with RACF ownership type. CONCLUSIONS: We partially confirmed other Australian findings about the relationship between RACF structural characteristics and regulatory sanctions and reported new findings about non-compliance notices. Routine and standardised public reporting of RACF performance is needed to build trust that Australia's latest aged care reforms have led to sustained quality improvements.

Linkage of the Avon Longitudinal Study of Parents and Children (ALSPAC) to Avon & Somerset Police regional police records.

This data note describes a new resource for crime-related research: the Avon Longitudinal Study of Parents and Children (ALSPAC) linked to regional police records. The police data were provided by Avon & Somerset Police (A&SP), whose area of responsibility contains the ALSPAC recruitment area. In total, ALSPAC had permission to link to crime records for 12,662 of the 'study children' (now adults, who were born in the early 1990s).  The linkage took place in two stages: Stage 1 involved the ALSPAC Data Linkage Team establishing the linkage using personal identifiers common to both the ALSPAC participant database and A&SP records using deterministic and probabilistic methods. Stage 2 involved A&SP extracting attribute data on the matched individuals, removing personal identifiers and securely sharing the de-identified records with ALSPAC. The police data extraction took place in July 2021, when the participants were in their late 20s/early 30s. This data note contains details on the resulting linked police records available. In brief, electronic police records were available from 2007 onwards. In total, 1757 participants (14%) linked to at least one police record for a charge, offence 'taken into consideration', caution, or another out of court disposal. Linked participants had a total of 6413 records relating to 6283 offences. Almost three quarters of the linked participants were male. The most common offence types were violence against the person (22% of records), drug offences (19%), theft (17%) and public order offences (11%). This data note also details important issues that researchers using the local police data should be aware of, including the importance of defining an appropriate denominator, completeness, and biases affecting police records.

A transparent and transportable methodology for evaluating Data Linkage software.

There has been substantial growth in Data Linkage (DL) activities in recent years. This reflects growth in both the demand for, and the supply of, linked or linkable data. Increased utilisation of DL "services" has brought with it increased need for impartial information about the suitability and performance capabilities of DL software programs and packages. Although evaluations of DL software exist; most have been restricted to the comparison of two or three packages. Evaluations of a large number of packages are rare because of the time and resource burden placed on the evaluators and the need for a suitable "gold standard" evaluation dataset. In this paper we present an evaluation methodology that overcomes a number of these difficulties. Our approach involves the generation and use of representative synthetic data; the execution of a series of linkages using a pre-defined linkage strategy; and the use of standard linkage quality metrics to assess performance. The methodology is both transparent and transportable, producing genuinely comparable results. The methodology was used by the Centre for Data Linkage (CDL) at Curtin University in an evaluation of ten DL software packages. It is also being used to evaluate larger linkage systems (not just packages). The methodology provides a unique opportunity to benchmark the quality of linkages in different operational environments.