Linkage Rates Research Articles

Assessing attitudes to ED-based HIV testing: Development of a short-structured survey instrument.

IntroductionEmergency Department (ED)-based HIV counseling and testing (HCT) has had a significant impact on improving rates of HIV diagnosis and linkage to care. Unfortunately, expansion of this strategy to low- and middle-income countries has been limited. Successful implementation of ED-based HCT is dependent on patient and provider acceptance of the intervention, and their attitudes and pre-existing biases towards the disease. This study sought to develop validated survey instruments to assess attitudes towards ED-based HCT.MethodsThis cross-sectional study surveyed patients and providers in three EDs in the Eastern Cape province, South Africa. A convenience sample of patients and providers in the ED were surveyed. Exploratory factor analysis was conducted using questions on attitudes to HIV testing to develop validated survey instruments. An ANOVA test assessed variance in attitudes towards HCT based on demographic variables collected.ResultsA total of 104 patient and 132 provider surveys were completed. Exploratory factor analysis resulted in a 17- and 7-question attitudes survey for patients and providers, respectively. Overall, 92.3% of patients and 70.7% of providers supported ED-based HCT, however, both groups displayed only mildly positive attitudes. Questions representing ‘confidentiality’ and ‘stigma around HIV testing’ had the least positive influence on patients’ overall attitudes. Questions representing ‘comfort with HIV testing’ had the least positive influence on providers’ overall attitudes.ConclusionOur study demonstrated ED patients and providers are generally supportive of ED-based HCT. A validated survey instrument was able to provide a standardized approach to identify barriers to HCT implementation in an ED setting, across contexts. For successful implementation, behavioral interventions must focus on strengthening patient beliefs around confidentiality and the consent process, and providers’ comfort levels with providing HIV testing services in the ED.

Linking national immigration data to provincial repositories: The case of Canada.

BackgroundCanadian health data repositories link datasets at the provincial level, based on their residents’ registrations to provincial health insurance plans. Linking national datasets with provincial health care registries poses several challenges that may result in misclassification and impact the estimation of linkage rates. A recent linkage of a federal immigration database in the province of Manitoba illustrates these challenges.Objectivesa) To describe the linkage of the federal Immigration, Refugees and Citizenship Canada Permanent Resident (IRCC-PR) database with the Manitoba healthcare registry and b) compare data linkage methods and rates between four Canadian provinces accounting for interprovincial mobility of immigrants.MethodsWe compared linkage rates by immigrant’s province of intended destination (province vs. rest of Canada). We used external nationwide immigrant tax filing records to approximate actual settlement and obtain linkage rates corrected for interprovincial mobility.ResultsThe immigrant linkage rates in Manitoba before and after accounting for interprovincial mobility were 84.8% and 96.1, respectively. Linkage rates did not substantially differ according to immigrants’ characteristics, with a few exceptions. Observed linkage rates across the four provinces ranged from 74.0% to 86.7%. After correction for interprovincial mobility, the estimated linkage rates increased > 10 percentage points for the provinces that stratified by intended destination (British Columbia and Manitoba) and decreased up to 18 percentage points for provinces that could not use immigration records of those who did not intend to settle in the province (New Brunswick and Ontario).ConclusionsDespite variations in methodology, provincial linkage rates were relatively high. The use of a national immigration dataset for linkage to provincial repositories allows a more comprehensive linkage than that of province-specific subsets. Observed linkage rates can be biased downwards by interprovincial migration, and methods that use external data sources can contribute to assessing potential selection bias and misclassification.

Pragmatic Experience with Risk-based versus Universal Hepatitis C Screening in Pregnancy: Detection of Infection and Postpartum Linkage to Care

Despite the Centers for Disease Control and Prevention (CDC) and U.S. Preventive Services Task Force (USPSTF) recommending universal hepatitis C virus (HCV) screening in pregnancy Society for Maternal-Fetal Medicine (SMFM) and American College of Obstetricians and Gynecologists (ACOG) continue to endorse risk-based screening for HCV in pregnancy. We hypothesized that universal screening is associated with increased HCV diagnosis and postpartum linkage to HCV care compared with risk-based screening. This retrospective cohort study included pregnant women screened for HCV at a single tertiary-care center. We defined two cohorts: women managed with risk-based (January 2014-October 2016) or universal HCV screening (November 2016-December 2018). Screening was performed with ELISA antibody testing and viremia confirmed with HCV ribonucleic acid (RNA) polymerase chain reaction (PCR). Primary outcomes were the rate of HCV screen positivity and postpartum linkage to care. From 2014 to 2018, 16,489 women delivered at our institution, of whom 166 screened positive for HCV. A total of 7,039 pregnant women were screened for HCV: 266 with risk-based and 6,773 with universal screening; 29% (76/266) were positive HCV antibody screening (HCVAb + ) in the risk-based cohort and 1.3% (90/6,773) in the universal cohort. HCVAb+ women in the risk-based cohort were more likely to have a positive drug screen. Only 69% (62/90) of HCVAb+ women in the universal cohort met the criteria for risk-based testing. Of the remaining 28 women, 6 (21%) had active viremia (HCV RNA+). Of the 166 HCVAb+ women, 64% (103/166) were HCV RNA+-51 of 266 (19%) in the risk-based and 52 of 6,773 (0.8%) in the universal cohort. Of HCVAb+ women, 75% (125/166) were referred postpartum for HCV evaluation and 27% (34/125) were linked to care. Only 9% (10/103) of women with viremia initiated treatment within 1 year of delivery. Universal HCV screening in pregnancy identified an additional 31% of HCVAb+ women compared with risk-based screening. Given low rates of HCV follow-up and treatment regardless of screening modality, further studies are needed to address barriers to postpartum linkage to care. · Ideal screening for HCV in pregnancy is unknown.. · We explore screening strategies in pregnancy to linkage to HCV care.. · Regardless of screening strategy there is low rates of postpartum linkage to HCV care..

Finding, treating and retaining persons with HIV in a high HIV prevalence and high treatment coverage country: Results from the Botswana Combination Prevention Project.

IntroductionThe scale-up of Universal Test and Treat has resulted in reductions in HIV morbidity, mortality and incidence. However, healthcare system and personal challenges have impacted the levels of treatment coverage achieved. We implemented interventions to improve linkage to care, retention, viral load (VL) coverage and service delivery, and describe the HIV care cascade over the course of the Botswana Combination Prevention Project (BCPP) study.MethodsBCPP was designed to evaluate the impact of prevention interventions on HIV incidence in 30 communities in Botswana. We followed a longitudinal cohort of newly identified and known HIV-positive persons not on antiretroviral therapy (ART) identified through community-based testing activities through BCPP and referred with appointments to local HIV clinics in 15 intervention communities. Those who did not keep the first or follow-up appointments were tracked and traced through phone and home contacts. Improvements to service delivery models in the intervention clinics were also implemented.ResultsA total of 3,657 newly identified or HIV-positive persons not on ART were identified and referred to their local HIV clinic; 90% (3,282/3,657) linked to care and of those, 93% (3,066/3,282) initiated treatment. Near the end of the study, 221 persons remained >90 days late for appointments or missing. Tracing efforts identified 54/3,066 (2%) persons who initiated treatment but died, and 106/3,066 (3%) persons were located and returned to treatment. At study end, 61/3,066 (2%) persons remained missing and were never reached. Overall, 2,951 (98%) persons living with HIV (PLHIV) who initiated treatment were still alive, retained in care and still receiving ART out of the 3,001 persons alive at the end of the study. Of those on ART, 2,854 (97%) had current VL results and 2,784 (98%) of those were virally suppressed at study end.ConclusionsThis study achieved high rates of linkage, treatment initiation, retention and VL coverage and suppression in a cohort of newly identified and known PLHIV not on ART. Tracking and tracing interventions effectively identified those persons who needed more resource intensive follow-up. The interventions implemented to improve service delivery and data quality may have also contributed to high linkage and retention rates.Clinical trial number: NCT01965470.

Probabilistic Linkage of Randomized Controlled Trial Data to Administrative Claims: A Case Study of Patients from Baricitinib Clinical Trials.

IntroductionThe aim of this work is to assess the feasibility of probabilistically linking randomized controlled trial (RCT) data to claims data in a real-world setting to inform future rheumatoid arthritis (RA) research.MethodsThis retrospective cohort study utilized IQVIA’s Patient Centric Medical Claims (Dx) Database, IQVIA’s Longitudinal Prescription Claims (LRx) Database, and Lilly’s baricitinib RCT data from a sample of patients that consented to the linkage of their de-identified insurance claims to their de-identified RCT data. Patients were initially matched on age, gender, and three-digit ZIP code of the provider and further matched according to a point scoring system using additional clinical variables.ResultsA total of 245 patients from 49 US clinical trial sites were eligible for the study and 78 (31.8%) of these patients consented to participate. Of the 78 consented patients, 69 (88%) were successfully matched on age, gender, and three-digit ZIP code of the provider. Of the 69 patients successfully matched on age, gender, and three-digit ZIP code of the provider, 44 (63.8%) had at least one sufficient match using the point scoring system. Of these 44, 23 (52.3%) patients matched at a ratio of one RCT patient to one Dx/LRx patient, 11 (25.0%) at a ratio of 1:2, 7 (15.9%) at a ratio of 1:3 and three (6.8%) at a ratio of 1:4 or greater. To further improve match ratios, a variable hierarchy was applied to the 18 RCT patients with 2–3 matches. Overall, 38 of the 78 (48.7%) consented RCT patients were successfully matched 1:1 to claims database patients.ConclusionsThis probabilistic linkage methodology demonstrates the feasibility, at a moderate linkage rate, of linking patients from RCTs to real-world data, which can provide a means to assess additional information not usually collected within or following a clinical trial.

Toward an all-inclusive trauma system in Central South Ontario: development of the Trauma-System Performance Improvement and Knowledge Exchange (T-SPIKE) project.

BackgroundThere is currently no integrated data system to capture the true burden of injury and its management within Ontario’s regional trauma networks (RTNs), largely owing to difficulties in identifying these patients across the multiple health care provider records. Our project represents an iterative effort to create the ability to chart the course of care for all injured patients within the Central South RTN.MethodsThrough broad stakeholder engagement of major health care provider organizations within the Central South RTN, we obtained research ethics board approval and established data-sharing agreements with multiple agencies. We tested identification of trauma cases from Jan. 1 to Dec. 31, 2017, and methods to link patient records between the various echelons of care to identify barriers to linkage and opportunities for administrative solutions.ResultsDuring 2017, potential trauma cases were identified within ground paramedic services (23 107 records), air medical transport services (196 records), referring hospitals (7194 records) and the lead trauma hospital trauma registry (1134 records). Linkage rates for medical records between services ranged from 49% to 92%.ConclusionWe successfully conceptualized and provided a preliminary demonstration of an initiative to collect, collate and accurately link primary data from acute trauma care providers for certain patients injured within the Central South RTN. Administration-level changes to the capture and management of trauma data represent the greatest opportunity for improvement.

Differences in inpatient and outpatient hepatitis C virus prevalence and linkage to care rates in a safety net hospital hepatitis C screening program.

Routine screening for hepatitis C virus (HCV) infection is crucial in identifying the 50% of infected persons unaware of their infection. We added an inpatient screening initiative to our successful outpatient HCV screening program in an urban, safety-net hospital. From March 2017 to December 2019, HCV screening was performed in inpatient and outpatient settings at Grady Health System. We compared care cascade outcomes, including anti-HCV testing, RNA testing, and linkage to care (LTC) between these settings. A total of 29751 patients were tested for anti-HCV: 8883 inpatients and 20868 outpatients. The anti-HCV population was predominantly Black (76.2%) and male (67.9%). The total anti-HCV prevalence was 8.9%, with 14% of inpatients and 6.7% of outpatients testing positive. RNA testing was performed on 86%. The prevalence of active HCV infection was 59.3% in those that were anti-HCV positive; inpatient prevalence was 66%, and outpatient was 53.8%. Of those with active infection, 67.5% were linked to care (57.3% of inpatients and 77.8% of outpatients). We found significant differences in prevalence of anti-HCV and LTC rates between inpatients and outpatients during an HCV screening program. Higher anti-HCV prevalence among inpatients may be due a higher prevalence of non-birth year HCV risk factors. LTC rates were lower in the inpatient setting despite a robust linkage strategy. The striking prevalence of HCV in both settings warrants continued screening, expansion to additional settings, and novel strategies to improve inpatient linkage rates, especially in the setting of new universal HCV screening guidelines.

Dinuclear Ce(IV) Aryloxides: Highly Active Catalysts for Anhydride/Epoxide Ring-Opening Copolymerization

A library of new dinuclear CeIV complexes of the type [NEt4]2[Ce2X6(TP)(sol)2] (X = Cl, ODipp, OSiMe3; sol = py, THF), where TP represents a family of tetraphenolate ligands that control intermetallic distance, are readily made in good yields. The ligands strongly stabilize the cerium +4 oxidation state and allow the incorporation of alkylammonium cocations in an “ate” complex formulation that enables them to be used as soluble, single-component catalysts for the ring-opening copolymerization (ROCOP) of a variety of anhydrides and epoxides. High turnover frequencies (TOFs) are achieved with high ester linkage selectivity, low dispersities, and rates that are highly tunable by the intermetallic distance enforced by the TP ligand, demonstrating that a closely coupled di-CeIV unit provides excellent rates of ROCOP catalysis and that, more generally, rare-earth complexes deserve further attention as ROCOP initiators.

Trauma in Schools: An Examination of Trauma Screening and Linkage to Behavioral Health Care in School-Based Health Centers.

This study examined trauma screening and behavioral health linkage rates in school-based health centers (SBHCs). Participants included 4161 English- and Spanish-speaking patients between the ages of 12 and 22 across 8 urban SBHCs 2 years. Screening rates at medical visits and linkage to additional behavioral health screening and services were assessed via electronic medical records and a chart audit. Medical providers administered the Primary Care-PTSD screen to 66.3% of patients in year 1 and 46.7% of patients in year 2. Rates of positive trauma screens were 27.5% and 32.1%, respectively, with more girls screening positive than boys. Few (year 1; 8.1%; year 2: 9.6%) adolescents received additional trauma screening by a behavioral health clinician. However, the majority were linked to services (year 1: 66%; year 2: 74%). Lack of documentation (year 1: 24%; year 2: 33%) was a common gap in the charts of patients who did not receive a second stage trauma screening. Demographic differences in screening rates were minimal. The current study supports the feasibility of traumatic stress screening and linkage within an integrated care setting. Process improvement efforts should, however, address communication gaps around trauma assessment and its integration into ongoing care.

Decentralisation, integration, and task-shifting in hepatitis C virus infection testing and treatment: a global systematic review and meta-analysis

SummaryBackgroundIncreasing access to hepatitis C virus (HCV) care and treatment will require simplified service delivery models. We aimed to evaluate the effects of decentralisation and integration of testing, care, and treatment with harm-reduction and other services, and task-shifting to non-specialists on outcomes across the HCV care continuum.MethodsFor this systematic review and meta-analysis, we searched PubMed, Embase, WHO Global Index Medicus, and conference abstracts for studies published between Jan 1, 2008, and Feb 20, 2018, that evaluated uptake of HCV testing, linkage to care, treatment, cure assessment, and sustained virological response at 12 weeks (SVR12) in people who inject drugs, people in prisons, people living with HIV, and the general population. Randomised controlled trials, non-randomised studies, and observational studies were eligible for inclusion. Studies with a sample size of ten or less for the largest denominator were excluded. Studies were categorised according to the level of decentralisation: full (testing and treatment at same site), partial (testing at decentralised site and referral elsewhere for treatment), or none. Task-shifting was categorised as treatment by specialists or non-specialists. Data on outcomes across the HCV care continuum (linkage to care, treatment uptake, and SVR12) were pooled using random-effects meta-analysis.FindingsOur search identified 8050 reports, of which 132 met the eligibility criteria, and an additional ten reports were identified from reference citations and grey literature. Therefore, the final synthesis included 142 studies from 34 countries (20 [14%] studies from low-income and middle-income countries) and a total of 489 996 patients (239 446 [49%] from low-income and middle-income countries). Rates of linkage to care were higher with full decentralisation compared with partial or no decentralisation among people who inject drugs (full 72% [95% CI 57–85] vs partial 53% [38–67] vs none 47% [11–84]) and among people in prisons (full 94% [79–100] vs partial 50% [29–71]), although the CIs overlap for people who inject drugs. Similarly, treatment uptake was higher with full decentralisation compared with partial or no decentralisation (people who inject drugs: full 73% [65–80] vs partial 66% [55–77] vs none 35% [23–48]; people in prisons: full 72% [48–91] vs partial 39% [17–63]), although CIs overlap for full versus partial decentralisation. The results in the general population studies were more heterogeneous. SVR12 rates were high (≥90%) across different levels of decentralisation in all populations. Task-shifting of care and treatment to a non-specialist was associated with similar SVR12 rates to treatment delivered by specialists. There was a severe or critical risk of bias for 46% of studies, and heterogeneity across studies tended to be very high (I2>90%).InterpretationDecentralisation and integration of HCV care to harm-reduction sites or primary care showed some evidence of improved access to testing, linkage to care, and treatment, and task-shifting of care and treatment to non-specialists was associated with similarly high cure rates to care delivered by specialists, across a range of populations and settings. These findings provide support for the adoption of decentralisation and task-shifting to non-specialists in national HCV programmes.FundingUnitaid.

Sexually Transmitted and Blood-borne Infections Among Patients Presenting to a Low-barrier Substance Use Disorder Medication Clinic.

To study the infection-related needs of patients with substance use disorders initiating care at a low-barrier-to-access program (LBAP) by describing the proportion with human immunodeficiency virus (HIV), hepatitis B and C virus (HBV, HCV), syphilis, gonorrhea, and chlamydia and determining rates of treatment and/or linkage to care. We reviewed the records of patients who completed an intake visit at an LBAP in Boston, MA during the first 9 months after implementation of a standardized intake laboratory panel (January 30, 2017-September 30, 2017). Among 393 patients initiating care, 84.7% (n = 333) completed at least 1 screening test. Baseline rates of HIV (9/393, 2.3%), current or past HCV (151/393, 38.4%), and chronic HBV (2/393, 0.5%) were high. Sixty-one new, active infections were identified through screening, including 1 HIV, 3 syphilis, 4 gonorrhea, 3 chlamydia, 1 chronic, and 1 acute HBV, and 48 cases of viremic HCV. Many patients were nonimmune to HBV (102/270, 37.8%) and HAV (112/255, 43.9%). Among new diagnoses, treatment was documented in 88% of bacterial infections and linkage occurred in 0/1 HIV, 2/2 HBV (100.0%), and 16/48 HCV (33.3%) cases. Patients initiating SUD care at an LBAP have substantial, unmet infection-related needs. Results justify the inclusion of comprehensive infection prevention, screening, and linkage-to-treatment protocols in LBAPs.

973. PrEP Care Continuum among Transgender Women at a Patient-Centered PrEP Program in Atlanta, GA

BackgroundHIV disproportionally affects transgender women (TGW) of color, with a prevalence of 26% and 44% among Latinx and Black TGW, respectively. Low medication adherence likely contributed to suboptimal pre-exposure prophylaxis (PrEP) efficacy among TGW in clinical trials, but real-world PrEP outcome data for TGW is limited. In this study, we developed the PrEP care continuum for TGW referred to a PrEP program at a large, safety-net urban hospital in the Southeast.Figure 1. PrEP care continuum of TGW referred a PrEP program. Referrals include all TGW referred to PrEP clinic, eligibility includes all those referred who were deemed eligible for PrEP, linkage refers to those eligible who had ongoing care at the PrEP clinic, prescription refers to those who received their first prescription of PrEP, initiation includes those who started taking the PrEP they were prescribed, and persistence includes those who had a visit within 6 months of study end. MethodsWe analyzed data for those referred to the PrEP program from 3/2018 to 2/2020. We determined the proportion of TGW who were linked to the program, provided a PrEP prescription, started PrEP, and persisted in PrEP care, defined as having at least one follow-up visit within 6 months. Using a multivariate regression model, including age, race, ethnicity, mental health co-morbidities, and substance use, we determined factors associated with persistence in PrEP care. We calculated rates of sexually transmitted infections (STIs) and HIV incidence.ResultsOf the 321 total referrals for PrEP, 42 (13%) were TGW. 81% of TGW were referred from a co-located gender clinic. Median age was 28.5 years (IQR 23-34), 62% were Black, 21% had mental health co-morbidities, 45% used substances, and 35% engaged in transactional sex. Of all TGW who were referred, 37 (88%) were eligible for PrEP and linked to care, 36 (85.7%) were prescribed and initiated PrEP, and 22 (52.4%) persisted in care at the end of the study period. There were no factors associated with persistence in PrEP care. The most common STIs during the first visit were pharyngeal gonorrhea (22.7%) and syphilis (16.7%). STI incidence was highest for rectal chlamydia (12.5%) and pharyngeal gonorrhea (6.5%). There was one HIV seroconversion during the study period.ConclusionIn a public hospital-based PrEP clinic in Atlanta with a co-located gender clinic, TGW had high rates of linkage to care and PrEP prescription and initiation, despite high rates of mental health diagnoses and substance use. However, there was a significant drop-off in persistence. STI prevalence and incidence were high, but there was only one HIV seroconversion, highlighting the potential benefits of PrEP. Future studies are needed to assess interventions to optimize persistence in PrEP care among TGW.DisclosuresBradley L. Smith, PharMD, AAHIVP, Gilead Sciences, Inc (Advisor or Review Panel member)

976. A Descriptive Retrospective Data Analysis of Maternal Sociodemographic Factors and Access of Healthcare Resources within the African Cohort Study, an Integrated Multicountry Preventative Mother to Child Transmission Program

BackgroundGlobal reduction in new infant HIV infections is largely due to the expansion of prevention of mother-to-child transmission (PMTCT) programs. Identification of gaps in healthcare services is paramount in targeting interventions that identify high-risk populations and healthcare barriers that could lead to increased risk of mother to child transmission (MTCT) of HIV.MethodsHIV infected women from 5 regions of Africa enrolled in the African Cohort Study (AFRICOS) were followed prospectively with assessments performed every 6 months. Sociodemographic factors, pregnancy outcomes, and access of PMTCT resources were reviewed for retrospectively reported pregnancies and those followed prospectively from study enrollment. Statistical analysis compared the impact of clinical factors on infant mortality and preterm delivery.ResultsThe study reported 5591 pregnancies from January 2013 to June 2019 of which 5363 were retrospectively reported prior to study enrollment and 228 occurred after enrollment. Pregnancies followed prospectively had higher rates of linkage to PMTCT services prenatally (92.5% vs 6.8%, P< 0.001), intrapartum (64.5% vs 3.5%, P< 0.001), and post-partum (64.5% vs 2.9%, P< 0.001). This group had higher rates of delivery by a skilled birth attendant (93.4% vs 66.7%, P< 0.001) and antiretroviral therapy (ART) prescribed antepartum (96.1% vs 5.5%, P< 0.001) and post-partum (74.6% vs 3.6%, P< 0.001). Both groups had similar rates of prescriptions for intrapartum ART (98.7% vs 97.9%). The majority of women reported ART adherence (96.5%, P< 0.001) which was associated with a decrease in both preterm delivery and infant mortality (adjusted OR 0.24, 95% CI 0.15-0.39). A significant proportion of women followed prospectively reported their infants received ART with good adherence (51.8% vs 0.3% and 93.4% vs 6.3%, respectively P< 0.001).ConclusionParticipation in AFRICOS increased linkage to PMTCT programs which resulted in increased likelihood of skilled delivery and appropriate ART use for women and their infants. It highlights that linkage to care continues to be a crucial factor in limiting MTCT of HIV especially in resource-limited settings. Limitations in this study exist due to the low number of prospectively followed pregnancies.Disclosures All Authors: No reported disclosures

Delays and Gaps in Progressing Through the Hepatitis C Virus Cascade of Care: An Underserved Safety-net Hospital Experience.

Background and ObjectiveWhile highly effective hepatitis C virus (HCV) therapies exist, gaps in the cascade of care remain. Disparities in the HCV cascade are prominent among underserved safety-net populations. We aim to evaluate the HCV cascade among an urban safety-net cohort of HCV patients.MethodsWe retrospectively evaluated adults with chronic HCV to determine rates of linkage to care (LTC), retention to care, and receiving HCV treatment from 2002 to 2018. Comparisons between groups utilized Chi-square testing; comparisons of median time to LTC and HCV treatment were evaluated with Student’s t-test and analysis of variance.ResultsAmong 600 chronic HCV patients (60.7% male, 20.7% non-Hispanic white, 49.2% African American, 92.5% treatment naïve, 26.8% cirrhosis), successful LTC within one year of HCV diagnosis was 57.7%, among which, 91.6% were successfully retained into care. In those with successful LTC, 72.6% received HCV treatment, 91.8% completed treatment, and 89% achieved SVR12. Women with HCV experienced longer delays from LTC to HCV treatment (331 vs. 206 days in men, P < 0.05), as did African Americans (280 vs. 165 days in non-Hispanic whites, P < 0.05). Compared to the non-Hispanic whites, HCV treatment was lower in African Americans (70.4% vs. 74.4%, P < 0.05).ConclusionWomen with HCV experienced significant delays along the HCV cascade, with median time of over 2 years from diagnosis to treatment. African Americans also experienced significant delays along the HCV cascade of care. However, sex and race/ethnicity were not found to be significant predictors of overall LTC or treatment.

Evaluating PPRL Vs Clear Text Linkage with Real-World Data

IntroductionPrivacy-preserving Record Linkage (PPRL) is a record linkage technique that can increase the security of personal information. PPRL uses techniques of either hashing identifiers (where exact matches are required) or Blooming identifiers (where partial matches are of interest before they are provided for linkage.&#x0D; Objectives and ApproachWe use LinXmart software to evaluate performance of PPRL linkage compared to linkage using clear text identifiers. The test linkage dataset is one that is routinely linked (N=2,672,257) at our linkage centre. The population spine (N=8,440,442) includes a record for every person who has resided in British Columbia, Canada over the past 30 years. Weights were determined using LinXmart’s implementation of the Expectation Maximization (EM) algorithm. For both linkages, accepted links were the highest-weighted candidate link with a weight above the threshold suggested by EM estimation. We compare linkage rates and quality and differences in weight and threshold estimations between clear-text and PPRL linkages&#x0D; ResultsClear-text and PPRL methods resulted in 97% and 90% linkage rates, respectively. Approximately 67% of records in the linked datasets contained a nominally unique ID. Records with a unique ID linked at higher rates (&gt;99% for both clear-text and PPRL) while the linkage rate for records missing the ID differed substantially (92% /70% for clear-text/PPRL). Comparing PPRL linkage to the clear-text linkage, we obtain F-measures of 0.99 and 0.80 for records with and without the unique ID, respectively.&#x0D; Conclusion / ImplicationsLinkage performance may be attributable to differences in comparison operators between the two methods. Bloomed fields compared with Dice coefficient allow for partial matching but may not be as sensitive as clear-text string comparisons. Numerical comparisons in PPRL are exact matches while clear-text comparisons allow for more sophisticated matching. Further refinements in PPRL are being explored to improve these results.

How Are Linkage Results Using Privacy-Preserving Record Linkage Different?

IntroductionPrivacy-Preserving Record Linkage (PPRL) presents opportunities to improve privacy protection when performing record linkage on the most sensitive data. Currently our linkage agency performs all linkages in clear text, but expansion of data sources is now including extremely sensitive data, such as justice data. Understanding that specific circumstances may demand different approaches to linkage, we evaluated a PPRL algorithm implemented through the LinXmart software. This is the first real-world evaluation of PPRL in British Columbia and among the first in Canada. Objectives and ApproachOur standard linkage method is probabilistic and relies on rules established by analysts to determine accepted links. Datasets are linked to a population spine (N=8,440,442) containing all current and past residents of the province. LinXmart was configured to link to the top weighted candidate above a predetermined confidence threshold. We evaluated performance by comparing the standard method to PPRL for three increasingly complex (messy) datasets. Initial results on the simplest/cleanest dataset informed an iterative process to improve implementation of PPRL. ResultsOverall linkage rates were lower for standard linkage (81%) compared to PPRL (90%). Records with a unique ID linked at similarly high rates in clear-text and PPRL, while the performance of PPRL with records without the unique ID varied depending on the exact parameters chosen for the match threshold and field comparisons. Conclusion / ImplicationsThis work suggests that for datasets that include a well-populated unique identifier, PPRL can be implemented in real-world linkages without a substantial drop-off in linkage quality. Messier data require careful tuning of linkage parameters to match the performance of clear linkage. PPRL may best be used in cases where clear text identifiers cannot be shared, and where some degradation in linkage rates is acceptable.

Linking Armed Forces Leavers to 2011 Census

IntroductionThe aim of this project was to meet a user need for more data on those who have served, and now left, the UK armed forces (service leavers) to support commitments under the Armed Forces Covenant. We explored the feasibility of linking the Veteran Leavers Database (VLD) held by the Ministry of Defence (MoD) to 2011 Census data held by the Office for National Statistics (ONS), Northern Ireland Statistics and Research Agency (NISRA).&#x0D; Objectives and ApproachThe Census for England, Wales and Northern Ireland consisted of a total number of 56 million records. The Ministry of Defence (MoD) provided the Veteran Leavers Database (VLD) which contained two million records of individuals who have left the armed forces since 1971.&#x0D; Postcode information was not available for this linkage, therefore a bespoke set of matchkeys was created and clerical review was carried out to determine the best set of recommended matchkeys. The linkage was carried out within the secure linkage environment using pseudonymised data to protect the identities of individuals within these datasets.&#x0D; Results53% of all VLD records linked to a Census record on one of the recommended matchkeys.&#x0D; Further quality analysis was carried out on the linkage rates by different years of exit which showed that, after 1975, the rate of matched records improved the closer the VLD entry was to Census year.&#x0D; Conclusion / ImplicationsONS have concluded that whilst there is value in the administrative datasets on service leavers, it only partially meets the user need. A census question has been developed and tested on service leavers and it has been concluded that such a question will work. ONS therefore now intending to recommend inclusion of this topic in the 2021 Census.

Using Linked Whole-Of-Population Data to Estimate Education-Related Inequalities in Cause-Specific Mortality in Australia

IntroductionOfficial Australian estimates of socioeconomic inequalities in cause-specific mortality have been based on area-level socioeconomic measures. Using area-level measures is known to underestimate inequalities.&#x0D; Objectives and ApproachUsing recently released census linked to mortality data, we estimate education-related inequalities in cause-specific mortality for Australia. We used 2016 Australian Census and Death Registration data (2016-17) linked via a Person Linkage Spine (linkage rates: 92% and 97%, respectively) from the Multi-Agency Data Integration Project (MADIP). Education, from the Census, was categorised as low (no secondary school graduation or other qualification), intermediate (secondary graduation with/without other non-tertiary qualifications) and high (tertiary qualification). Cause of death was coded according to the underlying cause of death using the ICD-10. We used negative binomial regression to estimate relative rates (RR) for cause-specific mortality at ages 25-84 years, in the 12-months following Census, comparing low vs high education, separately by sex and 20-year age group, adjusting for age.&#x0D; Results80,317 deaths occurred among 13,856,202 people. For those aged 25-44 years, relative inequalities were large for causes related to injury and smaller for lesspreventable deaths (e.g. for men, suicide RR=5.6, 95%CI: 4.1-7.5 and brain cancer RR=1.3, 0.6-3.1). For those aged 45-64, inequalities were large for causes related to health behaviours and amenable to medical intervention, e.g. lung cancer (men RR= 6.4, 4.7-8.8) and ischaemic heart disease (women RR=5.0, 3.2-7.7), and were small for less preventable causes e.g. brain cancer (women RR=0.9, 0.6-1.3). Patterns among those aged 65-84years were similar to those aged 45-64 years.&#x0D; Conclusion / ImplicationsIn Australia, inequalities in mortality are substantial. Our findings highlight the health burden from inequalities, opportunities for prevention and provide insights on targets to effectively reduce them.

Design and Creation of Multi-Source Enduring Linked Assets

IntroductionThe Australian Institute of Health and Welfare is collaborating with a range of government and other institutions to build enduring data assets for improving analysis and informed policy outcomes. There were lessons learnt that can be shared, in addition to the architecture and linkage techniques.&#x0D; The enduring assets were created by linking States’ and Territories’ health or welfare data to Commonwealth datasets such as Medicare Consumer Directory (MCD), Residential Aged Care (RAC) and National Death Index (NDI) data. The linkage was carried out by the Australian Institute of Health and Welfare (AIHW) Data Integration Services Centre (DISC).&#x0D; Objectives and ApproachTo create the integrated asset, the linkage spine was assembled by de-duplicating and linking MCD and NDI data. The states’ datasets and other commonwealth datasets involved in the project were linked to this spine. Each unique individual in the spine was assigned Personal Project Number (PPN) which was added to each record linked to the individual. The unlinked individuals from these datasets were de-duplicated and assigned different PPNs.&#x0D; Names, dates of birth and addresses were used in probabilistic linkage process.&#x0D; To enable investigators to interrogate the sequences of the events without releasing the exact dates, the central events file was created. It contains date differences for every event in the asset, calculated as the difference (in days) between event and not released “date zero”, different for each individual.&#x0D; ResultsBetween 96% and 99% of records in the supplied datasets were linked to the spine with linkage accuracy at least 98.5%. The linkage rates depends on the data completeness and the nature of the datasets as not all individuals accessing states’ servicers are eligible for Medicare.&#x0D; Conclusion / ImplicationsThe person-focused de-identified analytical assets allow to study journeys of the individual through Australian health and welfare systems which transcends jurisdictional boundaries.

Demonstrating the Utility of New Linked National Health Survey and Administrative Data: Secondary CVD Prevention in The Community

IntroductionCardiovascular events are largely preventable though access to timely quality primary health care and use of guideline-recommended medication. However, around half of Australians with cardiovascular disease (CVD) are not receiving best practice treatment. This study aims to identify factors associated with under treatment, using National Health Survey (NHS) linked for the first time to administrative health data.&#x0D; Objectives and ApproachParticipants with self-reported CVD in the NHS 2014-15 were included in the study, with data linked to Medicare (MBS) and pharmaceutical (PBS) data by the Australian Bureau of Statistics through the Multi-Agency Data Integration Project (MADIP). Use of primary and specialist ambulatory care and blood pressure- and lipid-lowering medications and their relation to sociodemographic and health characteristics were quantified using logistic and Poisson regression analyses.&#x0D; Results1100 participants with self-reported CVD were available for analysis, with linkage rates for NHS data to a Person Linkage Spine of 95%. We will present our findings from adjusted regression models (incomplete at time of abstract submission).&#x0D; Conclusion / ImplicationsThe nationally representative linked data developed under this project provides a unique opportunity to quantify and identify points to improve access to best practice CVD care, with the ultimate aim of preventing secondary CVD events in the population. Findings will also inform optimal use of MADIP data by the research community in order to answer questions of national importance and provide robust evidence to drive improvement in health and health care.