Targeted Testing for Bias in Order Assignment, with an Application to Texas Election Ballots

SARS-CoV-2 infection fatality ratios (IFR) remain controversially discussed with implications for political measures. The German county of Tirschenreuth suffered a severe SARS-CoV-2 outbreak in spring 2020, with particularly high case fatality ratio (CFR). To estimate seroprevalence, underreported infections, and IFR for the Tirschenreuth population aged ≥14 years in June/July 2020, we conducted a population-based study including home visits for the elderly, and analyzed 4203 participants for SARS-CoV-2 antibodies via three antibody tests. Latent class analysis yielded 8.6% standardized county-wide seroprevalence, a factor of underreported infections of 5.0, and 2.5% overall IFR. Seroprevalence was two-fold higher among medical workers and one third among current smokers with similar proportions of registered infections. While seroprevalence did not show an age-trend, the factor of underreported infections was 12.2 in the young versus 1.7 for ≥85-year-old. Age-specific IFRs were <0.5% below 60 years of age, 1.0% for age 60–69, and 13.2% for age 70+. Senior care homes accounted for 45% of COVID-19-related deaths, reflected by an IFR of 7.5% among individuals aged 70+ and an overall IFR of 1.4% when excluding senior care home residents from our computation. Our data underscore senior care home infections as key determinant of IFR additionally to age, insufficient targeted testing in the young, and the need for further investigations on behavioral or molecular causes of the fewer infections among current smokers.

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Doping practices in international weightlifting: analysis of sanctioned athletes/support personnel from 2008 to 2019 and retesting of samples from the 2008 and 2012 Olympic Games

Sports Medicine - Open ◽

10.1186/s40798-020-00293-4 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Alexander Kolliari-Turner ◽

Brian Oliver ◽

Giscard Lima ◽

John P. Mills ◽

Guan Wang ◽

...

Keyword(s):

Sensitivity And Specificity ◽

Regional Differences ◽

Olympic Games ◽

Anabolic Androgenic Steroid ◽

Sample Storage ◽

Support Personnel ◽

Androgenic Steroid ◽

In Doping ◽

Targeted Testing

Abstract Background The pervasiveness of doping and findings of anti-doping corruption threaten weightlifting’s position at the 2024 Olympic Games. Analysing the practices of doping in weightlifters could identify patterns in doping that assist in future detection. Methods We analysed publicly available data on sanctioned athletes/support personnel from the International Weightlifting Federation between 2008 and 2019 and announced retrospective Anti-Doping Rule Violations (ADRVs) from the 2008 and 2012 Olympic Games. Results There were 565 sanctions between 2008 and 2019 of which 82% related to the detection of exogenous Anabolic Androgenic Steroid (AAS) metabolites and markers indicating endogenous AAS usage. The detection of exogenous AAS metabolites, markers of endogenous AAS usage and other substance metabolites varied by IWF Continental Federation (p ≤ 0.05) with Europe (74%, 11%, 15%) and Asia (70%, 15%, 15%) showing a higher detection of exogenous AAS compared to Pan America (37%, 30%, 33%) and Africa (50%, 17%, 33%). When looking at the 10 most detected substances, the nations with the highest number of sanctions (range 17–35) all had at least one overrepresented substance that accounted for 38–60% of all detected substances. The targeted re-analysis of samples from the 2008 and 2012 Olympic Games due to the discovery of long-term metabolites for exogenous AAS resulted in 61 weightlifters producing retrospective ADRVs. This includes 34 original medallists (9 gold, 10 silver and 15 bronze), the highest of any sport identified by Olympic Games sample re-testing. The exogenous AAS dehydrochloromethyltestosterone and stanozolol accounted for 83% of detected substances and were present in 95% of these samples. Conclusion Based on these findings of regional differences in doping practices, weightlifting would benefit from the targeted testing of certain regions and continuing investment in long-term sample storage as the sensitivity and specificity of detection continues to improve.

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Managing cost uncertainties in transportation and assignment problems

Journal of Applied Mathematics and Decision Sciences ◽

10.1155/s1173912698000042 ◽

1998 ◽

Vol 2 (1) ◽

pp. 65-104 ◽

Cited By ~ 8

Author(s):

V. Adlakha ◽

H. Arsham

Keyword(s):

Time Lag ◽

Real Life ◽

Optimal Solution ◽

Global Market ◽

Solution Algorithm ◽

Assignment Problems ◽

The Stability ◽

Order Assignment ◽

Cost Parameters ◽

The Cost

In a fast changing global market, a manager is concerned with cost uncertainties of the cost matrix in transportation problems (TP) and assignment problems (AP).A time lag between the development and application of the model could cause cost parameters to assume different values when an optimal assignment is implemented. The manager might wish to determine the responsiveness of the current optimal solution to such uncertainties. A desirable tool is to construct a perturbation set (PS) of cost coeffcients which ensures the stability of an optimal solution under such uncertainties.The widely-used methods of solving the TP and AP are the stepping-stone (SS) method and the Hungarian method, respectively. Both methods fail to provide direct information to construct the needed PS. An added difficulty is that these problems might be highly pivotal degenerate. Therefore, the sensitivity results obtained via the available linear programming (LP) software might be misleading.We propose a unified pivotal solution algorithm for both TP and AP. The algorithm is free of pivotal degeneracy, which may cause cycling, and does not require any extra variables such as slack, surplus, or artificial variables used in dual and primal simplex. The algorithm permits higher-order assignment problems and side-constraints. Computational results comparing the proposed algorithm to the closely-related pivotal solution algorithm, the simplex, via the widely-used pack-age Lindo, are provided. The proposed algorithm has the advantage of being computationally practical, being easy to understand, and providing useful information for managers. The results empower the manager to assess and monitor various types of cost uncertainties encountered in real-life situations. Some illustrative numerical examples are also presented.

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Workplace risk management for SARS-CoV-2: a three-step early in-tervention strategy for effective containment of infection chains with special regards to virus variants with increased infectivity

10.1101/2021.07.21.21260756 ◽

2021 ◽

Author(s):

Andreas Paassen ◽

Laura Anderle ◽

Karsten John ◽

Sebastian Wilbrand

Keyword(s):

Risk Management ◽

Risk Analysis ◽

Scientific Knowledge ◽

Epidemiological Model ◽

Model Calculations ◽

Targeted Testing ◽

Alternative Measures

Background: Priority during the SARS-CoV2 pandemic is that employees need to be protected from infection risks and business activities need to be ensured. New virus variants with increased infec-tion risks require an evolved risk strategy. Material and methods: Several standard measures such as testing, isolation and quarantine are combined to a novel risk strategy. Epidemiological model calculations and scientific knowledge about the course of SARS-CoV2 infectivity are used to optimize this strategy. The procedure is implemented in an easy-to-use calculator based on Excel. Layout in practice and results: Alternative combinations of measures and practical aspects are discussed. Example calculations are used to demonstrate the effect of the discussed measures. Conclusion: That quarantine calculator derived from these principles enables even non-specialists to perform a differentiated risk analysis and to introduce optimized measures. Targeted testing routines and alternative measures ensure staff availability.

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Decreased Time to Viral Suppression After Implementation of Targeted Testing and Immediate Initiation of Treatment of Acute Human Immunodeficiency Virus Infection Among Men Who Have Sex With Men in Amsterdam

Clinical Infectious Diseases ◽

10.1093/cid/ciaa505 ◽

2020 ◽

Author(s):

Maartje Dijkstra ◽

Martijn S van Rooijen ◽

Mariska M Hillebregt ◽

Ard van Sighem ◽

Colette Smit ◽

...

Keyword(s):

Human Immunodeficiency Virus ◽

Hiv Infection ◽

Viral Suppression ◽

Standard Of Care ◽

Combination Antiretroviral Therapy ◽

Hiv Diagnosis ◽

Cart Initiation ◽

Immunodeficiency Virus ◽

Targeted Testing ◽

Sex With Men

Abstract Background Men who have sex with men (MSM) with acute human immunodeficiency virus (HIV) infection (AHI) are a key source of new infections. To curb transmission, we implemented a strategy for rapid AHI diagnosis and immediate initiation of combination antiretroviral therapy (cART) in Amsterdam MSM. We assessed its effectiveness in diagnosing AHI and decreasing the time to viral suppression. Methods We included 63 278 HIV testing visits in 2008–2017, during which 1013 MSM were diagnosed. Standard of care (SOC) included HIV diagnosis confirmation in < 1 week and cART initiation in < 1 month. The AHI strategy comprised same-visit diagnosis confirmation and immediate cART. Time from diagnosis to viral suppression was assessed for 3 cART initiation periods: (1) 2008–2011: cART initiation if CD4 < 500 cells/μL (SOC); (2) January 2012–July 2015: cART initiation if CD4 < 500 cells/μL, or if AHI or early HIV infection (SOC); and (3a) August 2015–June 2017: universal cART initiation (SOC) or (3b) August 2015–June 2017 (the AHI strategy). Results Before implementation of the AHI strategy, the proportion of AHI among HIV diagnoses was 0.6% (5/876); after implementation this was 11.0% (15/137). Median time (in days) to viral suppression during periods 1, 2, 3a, and 3b was 584 (interquartile range [IQR], 267–1065), 230 (IQR, 132–480), 95 (IQR, 63–136), and 55 (IQR, 31–72), respectively (P < .001). Conclusions Implementing the AHI strategy was successful in diagnosing AHI and significantly decreasing the time between HIV diagnosis and viral suppression.

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High Proportion of Indeterminate Qua.jpegERON-TB Gold In-Tube Results in an Inpatient Population Is Related to Host Factors and Preanalytical Steps

Open Forum Infectious Diseases ◽

10.1093/ofid/ofu088 ◽

2014 ◽

Vol 1 (2) ◽

Cited By ~ 7

Author(s):

Valeria Fabre ◽

Shmuel Shoham ◽

Kathleen R. Page ◽

Maunank Shah

Keyword(s):

Skin Testing ◽

Tertiary Care ◽

Latent Tuberculosis ◽

Host Factors ◽

Inpatient Setting ◽

Tuberculin Skin Testing ◽

Sample Collection ◽

Academic Center ◽

Targeted Testing ◽

Mitogen Response

Background. Qua.jpegERON-TB Gold In-Tube test (QFT-GIT) can be used as an alternative to tuberculin skin testing (TST) for the targeted testing of latent tuberculosis. Due to many shortcomings with TST, QFT-GIT usage is increasing. QFT-GIT implementation in the inpatient setting remains unclear. Methods. We retrospectively ide.jpegied patients admitted to a tertiary care academic center who received either a TST or a QFT-GIT in the 18 months prior to and after QFT-GIT implementation in March 2012. Risk factors associated with indeterminate results were evaluated. Results. The proportion of inpatients receiving a test for tuberculosis infection doubled following QFT-GIT implementation (1.4% vs 2.9%). After QFT-GIT became available, 75% of tested people received a QFT-GIT and 25% received a TST. We found indeterminate test results in 19.8%. Independent predictors of indeterminate results were female sex (adjusted odds ratio [AOR], 1.64), lymphopenia (AOR, 2.21), hypoalbuminemia (AOR, 6.81) and sample collection by nonphlebotomists (AOR, 3.0, vs phlebotomists). Of patients who had indeterminate results, 42% had a subsequent indeterminate result on repeat testing. All indeterminate results were due to a low mitogen response. Conclusions. QFT-GIT testing in the inpatient setting is associated with a high proportion of indeterminate results that is associated with host factors and preanalytical errors. Careful selection of patients to be tested and training on sample processing for QFT-GIT testing should be considered to decrease indeterminate results.

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