bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linking the Narcotics Monitoring System Database to Quantify the Contribution of Prescribed and Non-Prescribed Opioids to Opioid Overdoses in Ontario, Canada
Authors: Martins Diana , Singh Samantha , Khuu Wayne , Tadrous Mina , Paterson Michael , Juurlink David , Mamdani Muhammad , Gomes Tara 
Published: September 2018

IntroductionThe Ontario Narcotics Monitoring System (NMS) captures information on all prescriptions for controlled medications dispensed from outpatient pharmacies in Ontario, Canada, regardless of payer. This system was introduced in 2012, as a strategy to promote appropriate prescribing and dispensing practices.
Objectives and ApproachWe sought to explore the degree to which prescriptions in the NMS can be linked to other health claims databases, and describe the types of medications dispensed between July 2012 and December 2016. We also linked opioid prescriptions to hospitalization and mortality data to examine the relative contributions of prescribed and non-prescribed opioids to opioid toxicity events in 2016. A recent opioid prescription was defined as a prescription with a days’ supply that overlapped the opioid toxicity event. Analyses were stratified by gender and age.
ResultsWe examined 1.3 million prescriptions in the NMS during the study period: 72.8% for opioids, 21% for benzodiazepines, 4.4% for stimulants and <2% for other medications. Approximately 97% of prescriptions in the NMS could be linked because an Ontario health card was used at the time of dispensing. In 2016, we found that 52.8% of individuals with an opioid-related hospitalization (N=804/1,524) and 32.5% of those with an opioid-related death (N=278/855) had a recent opioid prescription. The proportion of opioid-related hospitalizations and deaths with a recent opioid prescription was significantly higher among females vs. males (57.2% vs. 48.0% and 45.6% vs. 26.4%, respectively; p<.001), and older (aged 45-64) vs. younger (aged 0-24) individuals (66.9% vs 9.9% and 46.4% vs 11.6% respectively; p<.001).
Conclusion/ImplicationsLinkage was possible for the majority of prescriptions in the NMS. We found that a large proportion of opioid overdoses involved a non-prescribed opioid, particularly among men and younger individuals. These findings highlight an important difference in patterns of opioid use and toxicities in the population that policy-makers should consider.
Automatic coding of nearly 2 million hospitalisation events to ICD-10 in the China Kadoorie Biobank
Authors: Sansome Sam , Turnbull Iain , McDonnell John 
Published: September 2018

IntroductionUsing linkage to the Chinese National Health Insurance (HI) system, we identified disease outcomes from a prospective cohort study of 512,000 middle-aged Chinese adults. Mandarin free-text diagnosis data were supplied by over 30 different agencies across 10 areas, often without an accompanying International Classification of Diseases 10th revision (ICD-10) code.
Objectives and ApproachTo facilitate a genome-wide association study (GWAS) of all our genotyped participants, we needed to code as many of our 2.02 million hospitalisation events as possible. We developed software to assign ICD-10 codes to unique disease descriptions and stored the coded diagnoses in an internal corpus. The software used an interface which allowed clinicians to select and code disease descriptions individually, or collectively using Chinese keywords. All coded disease descriptions were subsequently validated by an independent Mandarin-speaking clinician. All new events with descriptions which matched exactly those already in the corpus were automatically coded to ICD-10.
ResultsBy the end of 2016, there were 2,021,352 hospitalisation events coded to ICD-10. 436,702 (21.6%) were automatically assigned codes where disease descriptions corresponded to those in the Chinese version of the ICD-10 codebook. A further 1,084,197 (53.6%) were coded by a clinician using our standardisation software; all disease descriptions linked to 200 or more events were included. Finally, a remaining 454,237 (22.5%) events were given the ICD-10 codes supplied by the health insurance agency (after cleaning). In total, 97.7% of all health insurance events were coded to ICD-10. Overall, over 17,000 unique disease descriptions have been clinically classified.
Conclusion/ImplicationsAutomatic coding of hospitalisation events to ICD-10 has enabled our study to investigate a greater range of diseases and use GWAS to detect novel genetic variants. We are now well positioned to test semantic matching and machine learning strategies for coding of the remaining 46,216 (2.3%) uncoded events.
Validating Self-reported Chronic Conditions in Alberta’s Tomorrow Project Cohort: Data Linkage to Administrative Healthcare Data
Authors: Ye Ming , Vena Jennifer , Xu Jian-Yi , Robson Paula , Eurich Dean , Johnson Jeffrey 
Published: September 2018

IntroductionAlberta’s Tomorrow Project (ATP) is a province-wide cohort study of cancer and chronic diseases in Canada. Approximately 55,000 Albertans aged 35-69 years with no history of cancer, other than non-melanoma skin cancer, had joined the ATP. Nearly all (>96%) ATP participants consented to data linkage to administrative healthcare databases.
Objectives and ApproachTo validate chronic conditions self-reported by the ATP participants, individual-level data of a total of 52,851 ATP participants were linked to Alberta Health (AH) administrative datasets using Personal Health Number. Cases of chronic conditions, including diabetes, cardiovascular diseases and gastrointestinal disorders, were identified by algorithms for disease diagnosis using International Classification of Diseases (ICD) codes in administrative healthcare data. Cases were identified as “prevalent” if the index date of diagnosis was before or within 6 months of ATP enrollment date. Self-reported chronic conditions were validated by the cases identified as “prevalent” using the linked AH datasets.
ResultsAmong the ATP cohort, 804 participants self-reported ever being diagnosed with myocardial infarction (MI), 451 with stroke, 2,907 with diabetes, 566 with ulcerative colitis, 362 with Crohn’s disease and 112 with liver cirrhosis before or at the time of ATP enrollment. Using the linked AH administrative data, 339 participants were identified as prevalent cases with MI, 200 with stroke, 2,702 with diabetes, 208 with ulcerative colitis, 283 with Crohn’s disease and 55 with liver cirrhosis. The sensitivity and specificity of self-reporting having chronic conditions by the ATP participants were 71.1% and 97.0% for MI, 44.4% and 99.3% for stroke, 78.1% and 98.4% for diabetes, 73.6% and 99.2% for ulcerative colitis, 65.7% and 99.7% for Crohn’s disease and 50.9% and 99.8% for liver cirrhosis.
Conclusion/ImplicationsBy linking with administrative healthcare data, we were able to validate the accuracy of self-reporting chronic conditions in ATP participants. The sensitivity of self-reporting was acceptable for MI, diabetes, ulcerative colitis and Crohn’s disease, but low for stroke and liver cirrhosis. The specificity was high for all chronic conditions.
Preterm birth, unplanned hospital contact and mortality in infants born to teenage mothers in five countries: a cross-country comparison using linked administrative data
Authors: Harron Katie , Verfuerden Maximiliane , Ibiebele Ibinabo , Liu Can , Kopp Alex , Guttmann Astrid , Ford Jane , Van der Meulen Jan , Hjern Anders , Gilbert Ruth 
Published: September 2018

IntroductionChildren born to teenage mothers have greater healthcare needs than those born to mothers in their 20s and older, including higher rates of childhood hospitalisations. We performed a direct cross-country comparison of maternal age-related inequalities in infant outcomes in England, Scotland, Sweden, New South Wales (NSW; Australia) and Ontario (Canada).
Objectives and ApproachWe used administrative hospital data capturing 3,002,749 singleton births surviving to discharge between 2010-2014 (2008-2012 for Sweden). We derived risk ratios and risk differences to compare rates of preterm birth (24-37 weeks of gestation), unplanned hospital admissions, emergency department (ED) visits, and mortality within 12 months of postnatal discharge, for infants born to mothers aged 15-19, 20-24, 25-29 and 30-34 years.
ResultsInfants born to teenage mothers experienced higher rates of preterm birth, unplanned admissions, ED visits, and mortality compared with older mothers in all countries. Despite variation in the distribution of maternal characteristics between countries, inequalities according to maternal age were similar. Infants of teenage mothers were between 1.37 (95% CI for risk ratio 1.28-1.47, Sweden) and 1.56 (95% CI 1.49-1.64, NSW) times more likely to have ≥1 unplanned hospital admission and between 2.25 (95% CI 1.92-2.64, England) and 3.87 (95% CI 2.07-7.36, Sweden) times more likely to die, compared with those born to mothers aged 30-34.
Conclusion/ImplicationsA similar excess of adverse outcomes was observed for teenage mothers in all five countries, despite different prevalence rates and support for young families. Public health strategies are needed to address these inequalities, which may be due to social risk factors associated with both young motherhood and adverse infant outcomes.
Quantifying inequalities in mortality in Australia: the value of linked Census-morality data
Authors: Korda Rosemary , Biddle Nicholas , Eynstone-Hinkins James , Banks Emily , Lynch John , Priest Naomi 
Published: September 2018

IntroductionMortality rates are higher in disadvantaged communities. However, accurate quantification of inequalities in Australia has been limited by data availability. The Australian Bureau of Statistics has recently created a resource linking Death Registrations to Australian Census data, enabling quantification of mortality by whole-of-population individual-level measures.
Objectives and ApproachWe present the first analysis of linked Deaths Registrations to Census data, which quantifies mortality inequality in Australia in relation to individual-level socioeconomic position (SEP), and compares these estimates to those based on area-level-SEP measures. The Deaths Registrations-Census file contains deaths within 13 months of the 2011 Census date, linked probabilistically to 2011 Census data. We used Poisson regression to quantify inequalities according to education, weighted to adjust for relative under- and over-representation of selected subpopulations. We compared these inequality estimates with those based on area-SEP measures. We also examined the effect of missing Census data.
ResultsMortality rates decreased with education in all age groups (25-44, 45-64, 65-84, 85+ years), for both males and females. Estimates of relative inequality decreased with age, while estimates of absolute inequalities increased. Total excess deaths associated with lower education were highest in those aged 64-84 years. Inequality estimates for education were higher than those for area-SEP in the youngest age groups (25-45 years), but were lower in the 45-64 age group. Socioeconomic gradients in education remained apparent among individuals within each area-SEP quintile, highlighting the socioeconomic variation among individuals within these area-based socioeconomic groups. The proportion of deaths with missing education data increased with age and area-level SEP; however there was little difference in the area-based inequality estimates across subgroups with and without education missing.
Conclusion/ImplicationsThe newly-created linked Deaths Registrations-Census file, accessible through the virtual ABS Datalab, is a rich resource for generating evidence on mortality. The data show mortality inequalities in education across all age groups and within quintiles of area-level SEP and indicate area-based measures are inadequate for fully capturing inequality.
Data Byte: An Insight on Fetal Alcohol Spectrum Disorder and Educational Achievement
Authors: Piatt Carley , Lamba Navjot , Jia Ruiting , Werk Christine 
Published: September 2018

IntroductionData Bytes are bite-sized pieces of data from the longitudinal project, Experiences of Alberta Children and Youth Over Time, 2005-06 to 2010-11. To promote public engagement, the Data Byte series is designed to highlight a finding from a full report to give readers a quick data morsel to chew on.
Objectives and ApproachFetal Alcohol Spectrum Disorder (FASD) is a complex disorder caused by alcohol exposure during pregnancy. To understand how young people with FASD in Alberta are performing in schools, individually linked administrative data were used from 2005/06 to 2010/11. An individual was considered to have FASD if, at any point in the 6 years, they received a diagnostic code for fetal alcohol syndrome, or for being newborn affected by maternal use of alcohol (ICD 10-CA Q86.0 or P04.3) from a health service (emergency department or ambulatory care visit, or a hospitalization), or from a child disability service program.
ResultsOf young Albertans with FASD, almost 40% were meeting or exceeding educational expectations compared to 80% of young Albertans without a diagnosis of FASD. Expectations for educational achievement were computed by Alberta Education using age, grade, school type, special education codes, provincial achievement test scores, home education status, number of high school credits earned, number of higher level courses taken, average grade in higher level courses, possession of an Alberta Education certificate or diploma, and Alexander Rutherford scholarship eligibility.
Conclusion/ImplicationsData Bytes are designed to encourage stakeholders to explore:

Is the definition of “meeting educational expectations” used for the general population appropriate for a population with complex needs?
What other outcomes might be used to determine whether services are improving the quality of life for young Albertans with FASD?
Calgary Thrives: Data sharing and linkage in the not-for-profit sector.
Authors: Jagodzinski Robert , Pritchard Katharin , Lau Jason , Berzins Sandy , Perry Robert , Jafri Komal , Armstrong Debra , Pang Lily 
Published: September 2018

IntroductionCompared to the public sector, not-for-profits are less focused on cross-agency data linkage. Technical capacity is often secondary to addressing caseloads and protecting clients. Clients’ privacy is paramount and can be perceived as a barrier to collaboration between agencies. However, collaboration could streamline referrals and better assist vulnerable populations.
Objectives and ApproachSix not-for-profit agencies in Calgary, Canada participated in a data sharing project to measure various aspects of poverty and link data to determine cross-agency service usage. With this goal in mind, agencies examined their consent and data sharing practices to assess barriers to data sharing. There was a thorough exploration of client consent and how a client’s context can enable or limit data sharing. Cross-agency program usage was assessed among participating agencies using a privacy-preserving record linkage (PPRL) methodology.
ResultsAmongst the six participating agencies, four were deemed to have adequate technical capacity to share data. A contributing factor to the willingness of agencies to share data was the development of LinkWise: a PPRL software created and developed by PolicyWise. Linkage rates amongst three agencies were compared. Rates ranged from 47.8% to 0.23%. A higher linkage rate between two agencies indicated a small community based agency which provided many referrals to a larger agency, such as a food bank. Lower linkage rates on client intake may indicate an agency with many clients. It may also indicate differing socio-economic brackets for their clients’ catchment area.
Conclusion/ImplicationsWhile capacity, caseloads, and privacy protection restrict data sharing, not-for-profit agencies would benefit from a data sharing strategy. Linking data represent opportunities for collaboration within a significantly resource constrained sector. Moreover, it could more effectively address issues of vulnerable populations, streamline referrals for services, and facilitate quality improvement.
Linking air pollution and administrative health databases to examine health effects of wildfire smoke exposure in Calgary, Canada in 2015
Authors: Mahsin Md , Cabaj Jason , Saini Vineet 
Published: September 2018

IntroductionWildfires are increasing in frequency and severity due to climate change. Fine particulate matter (PM2.5) in wildfire smoke is an important indicator of health effects of most combustion sources. The evidence based on adverse health impacts of PM2.5 from wildfire smoke are increasingly being studied but some gaps still remain.
Objectives and ApproachWe examined the association of PM2.5 from Pacific Northwest wildfires with multiple respiratory and cardiovascular morbidity events related physician and emergency department visits, hospital admissions, health-link calls and medications dispensed among Calgary city population from August 1 – September 30, 2015. Physician billing claims, discharge abstract, Pharmaceutical Information Network, Health-link calls databases were linked with the air quality monitoring information database. Quasi-Poisson regression model for time lags of zero to five days and a three-day moving average, and conditional logistic regression model was used with adjustment for air pollutants and meteorological variables. Age and disease-specific stratified analyses were performed.
ResultsCompared to the pre-wildfire period (Aug 1 – Aug 23), a 10 µg/m3 increase in PM2.5 increased the risk for respiratory physician visits by 54.8% (95% CI: 41.6% - 69.3%) and 32.6% (95% CI: 10.4% - 58.9%) in the respective post (Sep 1- Sep 30) and during (Aug 24 – Aug 31) wildfire periods. The strongest association of PM2.5 with respiratory physician visits was observed for children aged 0-9 years in the post-wildfire period (Relative Risk [RR] = 2.11, 95% CI: 1.86 - 2.39) compared to during wildfire period (RR = 1.56, 95% CI: 1.21 - 2.02) and was consistent for asthma, acute bronchitis and acute respiratory infection. Statistically significant effects of PM2.5 on cardiovascular hospitalizations, ED and physician visits were not observed during the wildfire period.
Conclusion/ImplicationsWildfire-related PM2.5 led to increased physician visits due to respiratory morbidity during and after the wildfires, particularly for asthma, acute bronchitis and acute respiratory infections in children. The absence of cardiovascular health impact in general population during wildfires provides useful information for targeted public health messaging during adverse air quality events.
Linkage Quality Assessment for Anonymously linked Administrative Data.
Authors: Bhatt Hitesh , Jagodzinski Robert , Scott Allison N , Twilley Leslie , Cui Xinjie 
Published: September 2018

IntroductionLinked datasets are important resources for research, but linkage errors can lead to incorrect results. For data security and privacy concerns, when linkage of personal identifiers is performed anonymously, it is difficult to assess the quality of the linked dataset. We describe the method used to perform linkage quality.
Objectives and ApproachWe explored how to check the quality of linkages while preserving the privacy of individuals. We also adopted an approach that minimized time and burden on data providers involved in physical verification using randomly-generated appropriate sample sizes.
To validate these linkages, data providers were given random samples of 50 unique records from both linked and unlinked individuals across two other Government programs. Data providers were asked to look at the records associated with those individuals in their original datasets. Three types of linkage results were validated: cross-program linkages, cross-program non-linkages, and within-program linkages. Proportions of false-matches and missed-matches were estimated.
ResultsTwenty data providers checked their samples with two other programs which gave us a sample of 2000 individuals. The linkage process, based on anonymized personal identifiers, resulted in high true positive and high true negative rates. Agreement between human judges and the linkage software was strong. Results of this exercise and other linkage validation examinations provided confidence in the accuracy of the linkage process. With false matches occurring approximately only 3% of the time and virtually no missed-matches occurring, no adjustments were deemed necessary. Although linkage rates were reassuring, the sample sizes used for comparison were small, so it is expected that there would be significant variation associated with this 3% estimate; caution is advised in its use.
Conclusion/ImplicationsProportions of false-matches and missed-matches determine linkage quality which is the base for research when linkages are performed anonymously. A low proportion of false-matches and an absence of missed-matches was an indication of robust linkages.
Progress with Access to Cross-jurisdictional Linked Data in Australia
Authors: Wray Natalie , Flack Felicity , Smith Merran 
Published: September 2018

IntroductionAustralia is a federal, parliamentary, constitutional monarchy which consists of six states and two territories. As a result there is no single national data collection that follows individuals’ interactions with health and human services from birth to death. Therefore researchers need access to linked data from multiple jurisdictions.
Objectives and ApproachThe objective of this project was to evaluate the progress of the PHRN in providing researchers access to linkage infrastructure for cross-jurisdictional and multi-jurisdictional projects.
Data from the PHRN Online Application System (OAS) was analysed to determine:

The number of applications for linked data received
The number of jurisdictions involved in each application
The number of applications involving researchers from multiple jurisdictions
The number of applications involving linkage of state and Commonwealth data

An analysis of peer reviewed publications resulting from the use of the infrastructure was also conducted.
ResultsAustralia has a unique distributed national data linkage system which enables linkage of data both within and between jurisdictions. Each jurisdiction (state/territory and Commonwealth) has a linkage unit which provides linkage services within that jurisdiction. For cross-jurisdictional linkage, depending on the design of the specific project, the linkage is conducted either by the national data linkage unit or a combination of the national linkage unit and the state/territory data linkage units.
Analysis of the data from the OAS shows an increase in the applications for cross-jurisdictional and multi-jurisdictional linked data. There is a mix of requests for only state/territory data and for state/territory/Commonwealth data. The number of national collaborations and publications has also increased.
Conclusion/ImplicationsCross-jurisdictional linkage is challenging in a federated country. There are many legislative, regulatory and policy barriers. Despite these challenges, Australia has developed a national system enabling researchers to apply through a central system and for jurisdictions to work together to link and provide access to cross-jurisdictional and multi-jurisdictional data.