Patient-specific record linkage between emergency department and hospital admission data for a cohort of people who inject drugs: methodological considerations for frequent presenters
BackgroundPeople who inject drugs (PWID) have been identified as frequent users of emergency department (ED) and hospital inpatient services. The specific challenges of record linkage in cohorts with numerous administrative health records occurring in close proximity are not well understood. Here, we present a method for patient-specific record linkage of ED and hospital admission data for a cohort of PWID.MethodsData from 688 PWID were linked to two state-wide administrative health databases identifying all ED visits and hospital admissions for the cohort between January 2008 and June 2013. We linked patient-specific ED and hospital admissions data, using administrative date-time timestamps and pre-specified linkage criteria, to identify hospital admissions stemming from ED presentations for a given individual. The ability of standalone databases to identify linked ED visits or hospital admissions was examined.ResultsThere were 3459 ED visits and 1877 hospital admissions identified during the study period. Thirty-four percent of ED visits were linked to hospital admissions. Most links had hospital admission timestamps in-between or identical to their ED visit timestamps (n = 1035, 87%). Allowing 24-h between ED visits and hospital admissions captured more linked records, but increased manual inspection requirements. In linked records (n = 1190), the ED ‘departure status’ variable correctly reflected subsequent hospital admission in only 68% of cases. The hospital ‘admission type’ variable was non-specific in identifying if a preceding ED visit had occurred.ConclusionsLinking ED visits with subsequent hospital admissions in PWID requires access to date and time variables for accurate temporal sorting, especially for same-day presentations. Selecting time-windows to capture linked records requires discretion. Researchers risk under-ascertainment of hospital admissions if using ED data alone.
- Research Article
17
- 10.1111/acem.12054
- Jan 1, 2013
- Academic Emergency Medicine
The objective was to characterize the medical, social, and psychiatric correlates of frequent emergency department (ED) use among released prisoners with human immunodeficiency virus (HIV). Data on all ED visits by 151 released prisoners with HIV on antiretroviral therapy (ART) were prospectively collected for 12 months. Correlates of frequent ED use, defined as having two or more ED visits postrelease, were described using univariate and multivariate models and generated medical, psychiatric, and social multimorbidity indices. Forty-four (29%) of the 151 participants were defined as frequent ED users, accounting for 81% of the 227 ED visits. Frequent ED users were more likely than infrequent or nonusers to be female; have chronic medical illnesses that included seizures, asthma, and migraines; and have worse physical health-related quality of life (HRQoL). In multivariate Poisson regression models, frequent ED use was associated with lower physical HRQoL (odds ratio [OR] = 0.95, p = 0.02) and having not had prerelease discharge planning (OR = 3.16, p = 0.04). Frequent ED use was positively correlated with increasing psychiatric multimorbidity index values. Among released prisoners with HIV, frequent ED use is driven primarily by extensive comorbid medical and psychiatric illness. Frequent ED users were also less likely to have received prerelease discharge planning, suggesting missed opportunities for seamless linkages to care.
- Research Article
62
- 10.1186/1476-069x-11-70
- Sep 21, 2012
- Environmental Health
BackgroundEmergency department (ED) visit and hospital admissions (HA) data have been an indispensible resource for assessing acute morbidity impacts of air pollution. ED visits and HAs are types of health care visits with similarities, but also potentially important differences. Little previous information is available regarding the impact of health care visit type on observed acute air pollution-health associations from studies conducted for the same location, time period, outcome definitions and model specifications.MethodsAs part of a broader study of air pollution and health in St. Louis, individual-level ED and HA data were obtained for a 6.5 year period for acute care hospitals in the eight Missouri counties of the St. Louis metropolitan area. Patient demographic characteristics and diagnostic code distributions were compared for four visit types including ED visits, HAs, HAs that came through the ED, and non-elective HAs. Time-series analyses of the relationship between daily ambient ozone and PM2.5 and selected cardiorespiratory outcomes were conducted for each visit type.ResultsOur results indicate that, compared with ED patients, HA patients tended to be older, had evidence of greater severity for some outcomes, and had a different mix of specific outcomes. Consideration of ‘HA through ED’ appeared to more effectively select acute visits than consideration of ‘non-elective HA’. While outcomes with the strongest observed temporal associations with air pollutants tended to show strong associations for all visit types, we found some differences in observed associations for ED visits and HAs. For example, risk ratios for the respiratory disease-ozone association were 1.020 for ED visits and 1.004 for ‘HA through ED’; risk ratios for the asthma/wheeze-ozone association were 1.069 for ED visits and 1.106 for ‘HA through ED’. Several factors (e.g. age) were identified that may be responsible, in part, for the differences in observed associations.ConclusionsDemographic and diagnostic differences between visit types may lead to preference for one visit type over another for some questions and populations. The strengths of observed associations with air pollutants sometimes varied between different health care visit types, but the relative strengths of association generally were specific to the pollutant-outcome combination.
- Research Article
1
- 10.1200/jco.2020.39.28_suppl.241
- Oct 1, 2021
- Journal of Clinical Oncology
241 Background: Reducing ED visits in patients with cancer is cost saving and is particularly relevant during the COVID pandemic. We aim to identify patterns of ED visits among various cancer patients and reduce preventable ED visits and hospital admissions. Methods: We analyzed the number of ED visits and hospital admissions that occurred in patients with breast, lung, and Gastrointestinal (GI) cancers between July12019 and October31 2020 including demographics, stage, treatment type preceding the month of ED visit, reason, time of the day, day of the week the visit occurred. Results: 308 patients had 519 ED visits, 111 breast cancer patients had 184, 102 lung cancer patients had 186 and 95 GI cancer patients had 149 ED visits. 38% had > 1 visit. 51%, (37% breast, 60% Lung and 58 % GI cancer) had stage 4 disease at the time of visit. There were no visits in the month of May 2020. 275 (53%) visits required hospital admissions, 60% of ED visits in lung cancer, 54% in GI and 46 % in breast cancer patients required hospitalization. Most common reason for ED visits in breast cancer patients was fall/injury (20%), with median age of 71 years, none were cancer/ chemotherapy induced. Among lung and GI cancer patients respiratory (24%) and GI related (24%) symptoms were the most common reasons respectively, majority were cancer/chemotherapy related. Most common symptoms requiring hospital admissions were respiratory 21%, GI 18%, cardiac 12%. 11% and 9% of ED visits were due to fall/injury and cancer related pain, of these 3.6% and 9% resulted in hospital admissions respectively. Lung and GI cancer patients were more likely to be referred to the ED from the oncologist office (23%) than breast cancer patients (11%). Conclusions: Reasons for ED visits vary by tumor types and some may be preventable. Fall/injury in breast cancer patients and cancer related pain in lung and GI cancer patients were frequent reasons for preventable ED visits. In lung and GI cancer patients, cancer/chemotherapy related respiratory, GI symptoms are felt to be less avoidable since they may be related to disease progression or presenting symptoms. We have initiated several strategies such as ‘’systematic physical therapy assessment’’ of our breast cancer patients over age 70 to reduce ED visits due to fall/injury. We are developing strategies to involve palliative care early to reduce the number of ED visits related to cancer related pain We now have “call us first campaign” to assess and intervene before going to ED since most visits occurred during working hours.[Table: see text]
- Research Article
138
- 10.1111/acem.12347
- Apr 1, 2014
- Academic Emergency Medicine
The authors sought to describe the epidemiology of and risk factors for recurrent and high-frequency use of the emergency department (ED) by children. This was a retrospective cohort study using a database of children aged 0 to 17 years, inclusive, presenting to 22 EDs of the Pediatric Emergency Care Applied Research Network (PECARN) during 2007, with 12-month follow-up after each index visit. ED diagnoses for each visit were categorized as trauma, acute medical, or chronic medical conditions. Recurrent visits were defined as any repeat visit; high-frequency use was defined as four or more recurrent visits. Generalized estimating equations (GEEs) were used to measure the strength of associations between patient and visit characteristics and recurrent ED use. A total of 695,188 unique children had at least one ED visit each in 2007, with 455,588 recurrent ED visits in the 12 months following the index visits. Sixty-four percent of patients had no recurrent visits, 20% had one, 8% had two, 4% had three, and 4% had four or more recurrent visits. Acute medical diagnoses accounted for most visits regardless of the number of recurrent visits. As the number of recurrent visits per patient rose, chronic diseases were increasingly represented, with asthma being the most common ED diagnosis. Trauma-related diagnoses were more common among patients without recurrent visits than among those with high-frequency recurrent visits (28% vs. 9%; p<0.001). High-frequency recurrent visits were more often within the highest severity score classifications. In multivariable analysis, recurrent visits were associated with younger age, black or Hispanic race or ethnicity, and public health insurance. Risk factors for recurrent ED use by children include age, race and ethnicity, and insurance status. Although asthma plays an important role in recurrent ED use, acute illnesses account for the majority of recurrent ED visits.
- Research Article
5
- 10.1136/emermed-2022-212740
- May 10, 2023
- Emergency Medicine Journal
BackgroundAlthough frequent emergency department (ED) users have been widely studied in cross-sectional settings, there is some evidence suggesting that most frequent ED users do not remain frequent users over multiple...
- Research Article
- 10.1200/jco.2013.31.31_suppl.197
- Nov 1, 2013
- Journal of Clinical Oncology
197 Background: St. Michael’s Hospital (SMH) is an academic, inner-city hospital in Toronto, Canada. In the hematology/oncology (hem/onc) program, a small number of patients appeared to contribute disproportionately to hospital admissions and emergency department (ED) visits. We hypothesized that high needs hem/onc patients could be recognized early in their care and that ED visit and admission rates among these patients could be decreased through targeted interventions. Methods: Members of the hem/onc team were interviewed regarding characteristics, which they felt predicted higher needs and greater liklihood for hospital admission/ED visit. A list of high risk features was generated. ED visit and admission rates for a prospectively identified high needs cohort were compared to rates for the entire hem/onc clinic. An intervention targeting high needs hem/onc patients is on-going. Pre and post-intervention ED visit and admission rates will be compared. Results: Interviews with 3 nurses, 1 social worker, 1 discharge planner, and 4 physicians identified 10 factors that the hem/onc team believed were predictive of higher needs and subsequent higher ED visit and admission rates. Between December 1, 2012, and February 28, 2013, 42 high needs hem/onc out-patients were prospectively identified. The ED visit and admission rates for this cohort were retrospectively compared to those of the entire hem/onc clinic and found to be dramatically higher (Table). Begininng in June 2013, hem/onc patients identified as “high needs” were offered enrollment in a NP-based program offering telephone assessments following ED visits, hospital admissions or discharges. Assessment of the impact of this intervention is ongoing. Conclusions: It is possible to prospectively identify hem/onc patients who are at risk of higher than usual ED visit and admission rates. Identifying this population may provide an opportunity to decrease their ED visit and admission rates. An evaluation of an intervention targeting high needs hem/onc patients is ongoing. Preliminary data will be presented. [Table: see text]
- Research Article
129
- 10.1186/1476-069x-6-9
- Mar 21, 2007
- Environmental Health
BackgroundThe District of Columbia (DC) Department of Health, under a grant from the US Centers for Disease Control and Prevention, established an Environmental Public Health Tracking Program. As part of this program, the goals of this contextual pilot study are to quantify short-term associations between daily pediatric emergency department (ED) visits and admissions for asthma exacerbations with ozone and particulate concentrations, and broader associations with socio-economic status and age group.MethodsData included daily counts of de-identified asthma-related pediatric ED visits for DC residents and daily ozone and particulate concentrations during 2001–2004. Daily temperature, mold, and pollen measurements were also obtained. After a cubic spline was applied to control for long-term seasonal trends in the ED data, a Poisson regression analysis was applied to the time series of daily counts for selected age groups.ResultsAssociations between pediatric asthma ED visits and outdoor ozone concentrations were significant and strongest for the 5–12 year-old age group, for which a 0.01-ppm increase in ozone concentration indicated a mean 3.2% increase in daily ED visits and a mean 8.3% increase in daily ED admissions. However, the 1–4 yr old age group had the highest rate of asthma-related ED visits. For 1–17 yr olds, the rates of both asthma-related ED visits and admissions increased logarithmically with the percentage of children living below the poverty threshold, slowing when this percentage exceeded 30%.ConclusionSignificant associations were found between ozone concentrations and asthma-related ED visits, especially for 5–12 year olds. The result that the most significant ozone associations were not seen in the age group (1–4 yrs) with the highest rate of asthma-related ED visits may be related to the clinical difficulty in accurately diagnosing asthma among this age group. We observed real increases in relative risk of asthma ED visits for children living in higher poverty zip codes versus other zip codes, as well as similar logarithmic relationships for visits and admissions, which implies ED over-utilization may not be a factor. These results could suggest designs for future epidemiological studies that include more information on individual exposures and other risk factors.
- Research Article
1
- 10.1111/1475-6773.14430
- Jan 2, 2025
- Health services research
To compare healthcare services utilization across the healthcare system between frequent and non-frequent emergency department (ED) users among Medicaid enrollees in South Carolina. We conducted a retrospective, longitudinal study of individuals with at least one ED visit in 2017 in South Carolina and identified their healthcare services visits over 730 days (2 years) after their first ED visit. We classified individuals based on intensity of ED use: superfrequent (≥9 ED visits/year), frequent (4-8 ED visits/year), and non-frequent ED users (≤3 visits/year). We estimated differences between the three groups of ED users and non-ED hospital and office-based visits using multivariable two-part regression models. We used statewide Medicaid claims from January 2017 to December 2019 for ED users aged 18-64 years with continuous Medicaid enrollment. We analyzed data on all frequent and superfrequent users and selected a 4:1 random sample among all non-frequent users (~half of all non-frequent users). The study included 52,845 ED users, of whom 42,764 were non-frequent, 7677 frequent, and 2404 superfrequent users. Within 2 years from the date of their first ED visit, superfrequent ED users averaged 38.3 ED visits, frequent ED users 10.9 ED visits, and non-frequent ED users 2.6 ED visits (p < 0.001). Compared with non-frequent users, frequent and superfrequent ED users had more comorbidities and chronic conditions on average (1.6 vs. 3.5 vs. 6.4, p < 0.001). Both frequent and superfrequent users had more hospital visits beyond the ED overall (marginal effects: 0.23, 95% CI 0.18-0.27; 0.40, 95% CI 0.29-0.50), and more outpatient office visits overall (marginal effects: 4.39, 95% CI 2.52-6.27; 9.23, 95% CI 5.66-12.81), including primary care and most specialists' visits, compared with non-frequent users. Frequent ED users utilized non-ED hospital and outpatient office-based healthcare services significantly more than non-frequent ED users. These findings can guide tailored interventions using data across the healthcare system to efficiently coordinate care, contain costs, and improve health outcomes for these individuals.
- Abstract
- 10.5210/ojphi.v10i1.8797
- May 30, 2018
- Online Journal of Public Health Informatics
ObjeciveIdentify surveillance priorities for emergency department (ED) and Oregon Poison Center (OPC) data ahead of the 2017 Great American Solar Eclipse gatherings in Oregon and create a suite of queries for use in the Health Intelligence Section of the Oregon Public Health Division (OPHD) Incident Management Team (IMT).IntroductionOregon’s statewide syndromic surveillance system (Oregon ESSENCE) has been operational since 2012. Non-federal emergency department data (and several of their associated urgent care centers) are the primary source for the system, although other data sources have been added, including de-identified call data from OPC in 2016 (1).OPHD epidemiologists have experience monitoring mass gatherings (2) and have a strong relationship with OPC, collaborating on a regular basis for routine and heightened public health surveillance. Nevertheless, surveillance for the Great American Solar Eclipse (August 2017) presented a challenge due to the 107 reported simultaneous statewide eclipse-watching events planned for the day of the eclipse (some with estimated attendance of greater than 30,000 people and most in rural or frontier regions of the state).Scientific literature is limited on mass gathering surveillance in the developed world (3), particularly in rural settings (4), so OPC and OPHD worked together to develop a list of health conditions of interest, including some that would warrant both an ED visit and a call to OPC (e.g., snake bites). Monitoring visits in both data sources in would allow for assessment of total burden on the healthcare system, especially in the case of snake bites where only specific bites require administration of anti-venom.MethodsAhead of the planned mass gatherings, OPHD Health Intelligence and OPC compiled a list of expected risks from the literature (4,5) and input from members of the IMT including the Public Information Officer, who monitored media for stories about health. Priority health conditions presented a clear risk to public health (e.g., limited supply of snake anti-venom warranted surveillance of snake bites) or were the subject of substantial media coverage. Query development focused on risks that had specific, well-defined health effects and that would be captured by syndromic ED and OPC data.During an enhanced surveillance period (8/18-8/24), OPHD Health Intelligence reviewed and interpreted trends in common queries with OPC and disseminated a daily statewide surveillance report.ResultsOPHD and OPC created four new queries for both ED and OPC data streams: snake bites, psychedelic mushrooms, 2nd and 3rd degree body burns and eye-related calls and visits. ED queries used chief complaint, discharge diagnosis, or triage note. OPC queries used generic code, therapy and clinical effect.From 8/18-8/22, OPHD Health Intelligence distributed daily surveillance reports to the OPHD IMT and external partners. An increased in eye-related injuries was identified on the day after the eclipse, prompting OPHD Health Intelligence to consult with OPC. ED surveillance data indicated that the increase in eye-related visits was likely a seasonal trend. OPC staff reviewed the charts of patient calls captured by the query and concluded the calls were not related to retinal issues from looking at the sun. No other trends were noted in the joint OPHD/OPC queries.ConclusionsOPHD Health Intelligence piloted four new queries for surveillance during this mass gathering event and exercised the process for disseminating trend information from OPC and ED data. The eclipse event was fairly quiet and very few trends of note were captured by surveillance. Prior to this event, OPC data had not been a part of the Health Intelligence surveillance plan. However, assessing trends in OPC data provides an opportunity to better understand trends seen in ED data (e.g., whether or not a surge in ED visits for snake bites is accompanied by a surge in OPC calls for anti-venom is meaningful). By building a process to review disparate data in tandem, OPHD and OPC strengthened regional surveillance for this event. Applicable queries will continue to be used for planned event surveillance and several additional queries are currently under development.
- Abstract
- 10.5210/ojphi.v11i1.9765
- May 30, 2019
- Online Journal of Public Health Informatics
Optimization of Linkage between North Carolina EMS and ED Data: EMS Naloxone Cases
- Research Article
14
- 10.1111/acem.12457
- Sep 1, 2014
- Academic Emergency Medicine
The objective of this study was to calculate national estimates of depression-related emergency department (ED) visits and associated health care resource use among children and adolescents 17years or younger. Another goal was to explore the effects of certain sociodemographic and health care system factors and comorbidities on ED charges and subsequent hospitalization in the United States. The authors analyzed data from the 2006 and 2009 National Emergency Department Sample (NEDS), the largest source of U.S. ED data. ED visits with all listed diagnoses (i.e., principal diagnosis plus secondary conditions) of depression were identified using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes 293.83, 296.2X, 296.3X, 300.4, and 311. Population-based estimates of ED visits, hospitalization, resource use, comorbidities, and demographics associated with pediatric depression were calculated. Potentially significant covariate associations were also explored using ED charges and hospital admission from the ED. The 2006 and 2009 NEDS sample contained 365,713 ED visits for pediatric depression; the majority were made by adolescents (87.9%). Of these, 27.2% were admitted to the hospital, 69.5% were treated and released, and<0.1% died in ED. The ED charges in 2012 U.S. dollars summed to a hospital bill of $443.8 million, with the ED plus inpatient charges ($1.2 billion) being more than double that amount. The median inpatient length of stay (LOS) was 4.0days. Suicide and intentional self-inflicted injury were attempted by 31.4% of the patients. Attention-deficit, conduct, and disruptive disorders; anxiety disorders; substance use disorders; asthma; and infections were the most common comorbidities. In year 2009, a higher number of diagnoses, older age, being female, key comorbidities, and suicide and intentional self-inflicted injury were significantly associated with higher ED charges (all p<0.05). Increased odds of hospital admission from the ED were significantly associated with a higher number of diagnoses, key comorbidities, and suicide and intentional self-inflicted injury (all p<0.05). Pediatric depression is common in the ED and is associated with significant burden to the health care system. Certain factors such as a higher number of diagnoses, key comorbidities, and suicide and intentional self-inflicted injury are associated with increased health care costs and resource use. Special attention should be given to these factors, when present.
- Research Article
22
- 10.1161/jaha.120.018794
- Mar 5, 2021
- Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease
BackgroundIdentification of stroke patients at increased risk of emergency department (ED) visits or hospital admissions allows implementation of mitigation strategies. We evaluated the ability of the Patient‐Reported Outcomes Information Measurement System (PROMIS) patient‐reported outcomes (PROs) collected as part of routine care to predict 1‐year emergency department (ED) visits and admissions when added to other readily available clinical variables.Methods and ResultsThis was a cohort study of 1696 patients with ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, or transient ischemic attack seen in a cerebrovascular clinic from February 17, 2015, to June 11, 2018, who completed the following PROs at the visit: Patient Health Questionnaire‐9, Quality of Life in Neurological Disorders cognitive function, PROMIS Global Health, sleep disturbance, fatigue, anxiety, social role satisfaction, physical function, and pain interference. A series of logistic regression models was constructed to determine the ability of models that include PRO scores to predict 1‐year ED visits and all‐cause and unplanned admissions. In the 1 year following the PRO encounter date, 1046 ED visits occurred in 548 patients; 751 admissions occurred in 453 patients. All PROs were significantly associated with future ED visits and admissions except PROMIS sleep. Models predicting unplanned admissions had highest optimism‐corrected area under the curve (range, 0.684–0.724), followed by ED visits (range, 0.674–0.691) and then all‐cause admissions (range, 0.628–0.671). PROs measuring domains of mental health had stronger associations with ED visits; PROs measuring domains of physical health had stronger associations with admissions.ConclusionsPROMIS scales improve the ability to predict ED visits and admissions in patients with stroke. The differences in model performance and the most influential PROs in the prediction models suggest differences in factors influencing future hospital admissions and ED visits.
- Research Article
16
- 10.1371/journal.pone.0147450
- Jan 25, 2016
- PLOS ONE
The Korean National Health Insurance, which provides universal coverage for the entire Korean population, is now facing financial instability. Frequent emergency department (ED) users may represent a medically vulnerable population who could benefit from interventions that both improve care and lower costs. To understand the nature of frequent ED users in Korea, we analyzed claims data from a population-based national representative sample. We performed both bivariate and multivariable analyses to investigate the association between patient characteristics and frequent ED use (4+ ED visits in a year) using claims data of a 1% random sample of the Korean population, collected in 2009. Among 156,246 total ED users, 4,835 (3.1%) were frequent ED users. These patients accounted for 14% of 209,326 total ED visits and 17.2% of $76,253,784 total medical expenses generated from all ED visits in the 1% data sample. Frequent ED users tended to be older, male, and of lower socio-economic status compared with occasional ED users (p < 0.001 for each). Moreover, frequent ED users had longer stays in the hospital when admitted, higher probability of undergoing an operative procedure, and increased mortality. Among 8,425 primary diagnoses, alcohol-related complaints and schizophrenia showed the strongest positive correlation with the number of ED visits. Among the frequent ED users, mortality and annual outpatient department visits were significantly lower in the alcohol-related patient subgroup compared with other frequent ED users; furthermore, the rate was even lower than that for non-frequent ED users. Our findings suggest that expanding mental health and alcohol treatment programs may be a reasonable strategy to decrease the dependence of these patients on the ED.
- Research Article
3
- 10.1007/s00521-003-0366-z
- Sep 1, 2003
- Neural Computing & Applications
Historical data for hospital admissions and Emergency Department (ED) visits in Baltimore City contain information concerning temporal patterns of paediatric asthma service utilisation (e.g. number of peaks and troughs, timing, relative magnitudes, steepness of rise and fall of the endemic cycles, etc.). This historical information can be captured by linear and neural network models to accurately predict the level of asthma admissions for the next few days or one week. Using 14 years of data, the best neural network models explained over 80% of the variations in admissions data with root mean square errors of 5–7 admissions per week. Models developed to predict asthma admissions can aid in identifying future peak periods of asthma admissions, alerting and educating individual asthmatic patients to periods of increased risk, and mitigating asthma events that lead to ED and/or hospital admissions. It is believed that these modelling techniques using historical data can be applied to any city or region with similar accuracies.
- Research Article
37
- 10.1016/j.amjcard.2014.02.020
- Mar 1, 2014
- The American Journal of Cardiology
Analysis of Emergency Department Visits for Palpitations (from the National Hospital Ambulatory Medical Care Survey)
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