scholarly journals The first GAEN-based COVID-19 contact tracing app in Norway identifies 80% of close contacts in "real life" scenarios.

2021 ◽  
Author(s):  
Hinta Meijerink ◽  
Elisabeth H. Madslien ◽  
Camilla Mauroy ◽  
Mia Karoline Johansen ◽  
Sindre Mogster Braaten ◽  
...  
Keyword(s):  
Operating Systems ◽  
Real Life ◽  
Contact Tracing ◽  
P Value ◽  
Notification Rate ◽  
P Values ◽  
Time Threshold ◽  
Multiple Weights ◽  
Optimal Setting ◽  
Close Contacts

The COVID-19 response in most countries depends on testing, isolation, contact tracing, and quarantine, which is labor- and time consuming. Therefore, several countries worldwide launched Bluetooth based apps as supplemental tools. We evaluated the new Norwegian GAEN (Google Apple Exposure Notification) based contact tracing app 'Smittestopp' under two relevant simulated scenarios, namely standing in a queue and riding public transport. We compared two configurations (C1: 58/63 dBm; C2: 58/68 dBm) with multiple weights (1.0-2.5) and time thresholds (10-15 min), by calculating notification rates among close contacts (≤2 meters, ≥15 min) and other non-close contacts. In addition, we estimated the effect of using different operating systems and locations of phone (hand/pocket) using Chi2. C2 resulted in significantly higher notification rates than C1 (p-value 0.05 - 0.005). The optimal setting resulted in notifications among 80% of close contacts and 34% of other contacts, using C2 with weights of 2.0 for the low and 1.5 for the middle bucket with a 13-minutes time threshold. Among other contacts, the notification rate was 67% among those ≤2 meters for <15 minutes compared to 19% among those >2 meters (p=0.004). Significantly (p-values 0.046 - 0.001) lower notification rates were observed when using the iOS operating systems or carrying the phone in the pocket instead of in the hand. This study highlights the importance of testing and optimizing the performance of contact tracing apps under 'real life' conditions to optimized configuration for identifying close contacts.

scholarly journals The First GAEN-Based COVID-19 Contact Tracing App in Norway Identifies 80% of Close Contacts in “Real Life” Scenarios

2021 ◽  
Vol 3 ◽  
Author(s):  
Hinta Meijerink ◽  
Camilla Mauroy ◽  
Mia Karoline Johansen ◽  
Sindre Møgster Braaten ◽  
Christine Ursin Steen Lunde ◽  
...  
Keyword(s):  
Operating Systems ◽  
Real Life ◽  
Contact Tracing ◽  
Lower Sensitivity ◽  
Life Test ◽  
Public Places ◽  
Per Se ◽  
The Impact ◽  
Test Scenarios ◽  
Close Contacts

The coronavirus disease 2019 (COVID-19) response in most countries has relied on testing, isolation, contact tracing, and quarantine (TITQ), which is labor- and time-consuming. Therefore, several countries worldwide launched Bluetooth-based apps as supplementary tools. The aim of using contact tracing apps is to rapidly notify people about their possible exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and thus make the process of TITQ more efficient, especially upon exposure in public places. We evaluated the Norwegian Google Apple exposure notification (GAEN)-based contact tracing app Smittestopp v2 under relevant “real-life” test scenarios. We used a total of 40 devices, representing six different brands, and compared two different exposure configurations, experimented with different time thresholds and weights of the Bluetooth attenuation levels (buckets), and calculated the true notification rates among close contacts (≤2 m and ≥15 min) and false notification of sporadic contacts. In addition, we assessed the impact of using different operating systems and locations of the phone (hand/pocket). The best configuration tested to trigger exposure notification resulted in the correct notification of 80% of the true close contacts and incorrect notification of 34% of the sporadic contacts. Among those who incorrectly received notifications, most (67%) were within 2 m but the duration of contact was &lt;15 min and thus they were not, per se, considered as “close contacts.” Lower sensitivity was observed when using the iOS operating systems or carrying the phone in the pocket instead of in the hand. The results of this study were used to improve and evaluate the performance of the Norwegian contact-tracing app Smittestopp.

scholarly journals Letermovir Primary Prophylaxis in High-Risk Hematopoietic Cell Transplant Recipients: A Matched Cohort Study

Vaccines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 372
Author(s):  
Léna Royston ◽  
Eva Royston ◽  
Stavroula Masouridi-Levrat ◽  
Nathalie Vernaz ◽  
Yves Chalandon ◽  
...  
Keyword(s):  
Renal Function ◽  
Cohort Study ◽  
High Risk ◽  
Real Life ◽  
Primary Prophylaxis ◽  
Hematopoietic Cell ◽  
P Value ◽  
Cell Transplant ◽  
Matched Cohort ◽  
Matched Cohort Study

Background: Real-life data on the administration of letermovir as cytomegalovirus (CMV) primary prophylaxis after allogeneic hematopoietic cell transplantation (HCT) remain limited. Methods: We conducted a retrospective single-center matched cohort study, comparing consecutive high-risk allogeneic HCT recipients (cases) receiving primary prophylaxis with letermovir and untreated matched historical controls, during a study period of 180 days. The primary outcome was the incidence of clinically significant (cs) CMV infection. Secondary outcomes included duration and costs of CMV-antiviral treatments, hospital resource utilization, hematology and laboratory parameters. Results: Letermovir prophylaxis decreased csCMV infection incidence from 82.7% (controls) to 34.5% (cases; p-value < 0.0001). Controls were more likely to have >1 episode of csCMV infection (59.6%) compared to cases (11.5%; p-value < 0.0001). Letermovir was associated with: shorter overall CMV-associated treatment duration (49 days vs. 77.8 days; p-value: 0.02) and a trend for lower costs of CMV-associated treatments ($4096 vs. $9736; p-value: 0.07) and reduced length of stay (44.8 days vs. 59.8 days; p-value: 0.16). Letermovir administration was associated with significantly shorter duration (27.3 days vs. 57.1 days; p-value: 0.008) and lower costs ($1089 vs. $2281; p-value: 0.008) of valganciclovir treatment. Compared to controls, higher platelet counts were observed in cases (138 G/L vs. 92 G/L; p-value: 0.03) and renal function was improved (94 mL/min/1.73 m2 vs. 74 mL/min/1.73 m2; p-value: 0.006). Conclusions: Primary anti-CMV letermovir prophylaxis decreased the incidence of csCMV infection and the administration of CMV-associated treatments and costs, particularly those associated with valganciclovir. An effect of letermovir on platelet reconstitution and renal function of csCMV post-HCT was observed and needs further investigation.

scholarly journals Assessing testing strategies and duration of quarantine in contact tracing for SARS-CoV-2: a retrospective study of San Francisco’s COVID-19 contact tracing program, June- August, 2020

2021 ◽  
Author(s):  
M J A Reid ◽  
P Prado ◽  
H Brosnan ◽  
A Ernst ◽  
H Spindler ◽  
...  
Keyword(s):  
Retrospective Study ◽  
San Francisco ◽  
Contact Tracing ◽  
Testing Strategies ◽  
Close Contacts

Abstract We sought to assess the proportion of elicited close contacts diagnosed with COVID-19 at the start, and before exiting quarantine, in San Francisco, USA. From June 8th to August 31st, 6946 contacts were identified; 3008 (46.3%) tested, 940 (13.5%) tested positive; 90% tested positive in first 9 days of quarantine.

scholarly journals SAT0210 FACTORS ASSOCIATED WITH TIME TO SEVERE LUPUS NEPHRITIS IN A COHORT OF COLOMBIAN PATIENTS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1048.2-1048
Author(s):  
S. Herrera ◽  
J. C. Diaz-Coronado ◽  
D. Rojas-Gualdrón ◽  
L. Betancur-Vasquez ◽  
D. Gonzalez-Hurtado ◽  
...  
Keyword(s):  
Lupus Nephritis ◽  
Renal Involvement ◽  
Classification Criteria ◽  
P Value ◽  
Systemic Lupus ◽  
P Values ◽  
Interval Censored ◽  
Severe Lupus Nephritis ◽  
Age And Sex

Background:Systemic lupus erythematosus (SLE) clinical manifestations, and their severity, vary according to age, ethnicity and socioeconomic status. Both Hispanic and Afro-Americans have a higher incidence and more sever presentation when compared to Caucasian patients with SLEObjectives:To analyze clinical and immunological characteristics associated with time to severe renal involvement in patients with Systemic Lupus Erythematous in a Colombian cohort followed for one year, between January 2015 and December 2018Methods:Retrospective follow-up study based in clinical records. Patients with SLE diagnosis that fulfilled either 1987 American College of Rheumatology Classification Criteria for SLE or 2011 Systemic Lupus International Collaborating Clinics (SLICC) classification criteria for SLE. We included patients with diagnosis of lupus nephritis according to Wallace and Dubois criteria. Patients who did not have at least two follow-up measurements or had a cause of nephritis other than lupus were excluded. The main outcome was defined as time from diagnosis to sever renal involvement defined as creatinine clearance ≤50 ml/min, 24-hour proteinuria ≥3.5 grams o end stage renal disease.We analyzed clinical and immunological characteristics. Descriptive statistical analyses of participant data during the first evaluation are reported as frequencies and percentages for categorical variables, and as medians and interquartile ranges (IQR) for quantitative variables. Age and sex adjusted survival functions and Hazard ratios (HR) with 95% confidence intervals and p-values were estimated using parametric Weibull models por interval-censored data. P values < 0.05 were considered statistically significantResults:548 patients were analyzed: 67 were left-censored as they presented renal involvement at entry, 6 were interval censored as outcome occurred between study visits, and 475 were right-censored as involvement was not registered during follow-up. 529 (96.5%) patients were female, median age at entry was 46 (IQR = 23) and median age to diagnosis was 29.5 (IQR = 20.6). 67% were mestizo, 13% Caucasian and 0.3% Afro-Colombian. Age and sex adjusted variables associated with time to severe lupus nephritis were high blood pressure HR = 3.5 (95%CI 2.2-5.6; p-value <0.001) and Anti-RO (per unit increase) HR = 1.002 (95%CI 1.001-1.004; p-value = 0.04). Figure 1 shows age and sex adjusted survival function.Conclusion:In our cohort the appearance of severe lupus nephritis occurs in less than 15% of patients at 10 years. Both high blood pressure and elevated anti-Ro titers were associated with a higher rate of onset in the presentation of severe lupus nephritis, as seen in some polymorphs of anti Ro.References:Disclosure of Interests:Sebastian Herrera Speakers bureau: academic conference, Juan camilo Diaz-Coronado: None declared, Diego Rojas-Gualdrón: None declared, Laura Betancur-Vasquez: None declared, Daniel Gonzalez-Hurtado: None declared, Juanita Gonzalez-Arango: None declared, laura Uribe-Arango: None declared, Maria Fernanda Saavedra Chacón: None declared, Jorge Lacouture-Fierro: None declared, Santiago Monsalve: None declared, Sebastian Guerra-Zarama: None declared, Juan david Lopez: None declared, Juan david Serna: None declared, Julian Barbosa: None declared, Ana Sierra: None declared, Deicy Hernandez-Parra: None declared, Ricardo Pineda.Tamayo: None declared

NO EVIDENCE, OR NOT ENOUGH EVIDENCE?

PEDIATRICS ◽  
1996 ◽  
Vol 98 (6) ◽  
pp. A22-A22
Author(s):  
Student
Keyword(s):  
Confidence Intervals ◽  
P Value ◽  
P Values ◽  
Considerable Uncertainty ◽  
Absence Of Evidence

When we are told that "there's no evidence that A causes B," we should first ask whether absence of evidence means simply that there is no information at all. If there are data, we should look for quantification of the association rather than just a P value. Where risks are small, P values may well mislead: confidence intervals are likely to be wide, indicating considerable uncertainty.

Abstract MP11: Circulating Plasma Biomarkers Associated With Brain Arteriovenous Malformations

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Sarah E Wetzel-Strong ◽  
Shantel M Weinsheimer ◽  
Jeffrey Nelson ◽  
Ludmila Pawlikowska ◽  
Dewi Clark ◽  
...  
Keyword(s):  
Multiple Testing ◽  
Statistical Significance ◽  
Protein Profiling ◽  
P Value ◽  
P Values ◽  
Plasma Biomarkers ◽  
Standard Curve ◽  
Disease States ◽  
Heparin Plasma ◽  
Circulating Levels

Objective: Circulating plasma protein profiling may aid in the identification of cerebrovascular disease signatures. This study aimed to identify circulating angiogenic and inflammatory biomarkers that may serve as biomarkers to differentiate sporadic brain arteriovenous malformation (bAVM) patients from other conditions with brain AVMs, including hereditary hemorrhagic telangiectasia (HHT) patients. Methods: The Quantibody Human Angiogenesis Array 1000 (Raybiotech) is an ELISA multiplex panel that was used to assess the levels of 60 proteins related to angiogenesis and inflammation in heparin plasma samples from 13 sporadic unruptured bAVM patients (69% male, mean age 51 years) and 37 patients with HHT (40% male, mean age 47 years, n=19 (51%) with bAVM). The Quantibody Q-Analyzer tool was used to calculate biomarker concentrations based on the standard curve for each marker and log-transformed marker levels were evaluated for associations between disease states using a multivariable interval regression model adjusted for age, sex, ethnicity and collection site. Statistical significance was based on Bonferroni correction for multiple testing of 60 biomarkers (P< 8.3x10 - 4 ). Results: Circulating levels of two plasma proteins differed significantly between sporadic bAVM and HHT patients: PDGF-BB (P=2.6x10 -4 , PI= 3.37, 95% CI:1.76-6.46) and CCL5 (P=6.0x10 -6 , PI=3.50, 95% CI=2.04-6.03). When considering markers with a nominal p-value of less than 0.01, MMP1 and angiostatin levels also differed between patients with sporadic bAVM and HHT. Markers with nominal p-values less than 0.05 when comparing sporadic brain AVM and HHT patients also included angiostatin, IL2, VEGF, GRO, CXCL16, ITAC, and TGFB3. Among HHT patients, the circulating levels of UPAR and IL6 were elevated in patients with documented bAVMs when considering markers with nominal p-values less than 0.05. Conclusions: This study identified differential expression of two promising plasma biomarkers that differentiate sporadic bAVMs from patients with HHT. Furthermore, this study allowed us to evaluate markers that are associated with the presence of bAVMs in HHT patients, which may offer insight into mechanisms underlying bAVM pathophysiology.

scholarly journals Not p-Values, Said a Little Bit Differently

Econometrics ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 11 ◽  
Author(s):  
Richard Startz
Keyword(s):  
P Value ◽  
P Values ◽  
Numerical Examples ◽  
Practical Matter ◽  
The One

As a contribution toward the ongoing discussion about the use and mis-use of p-values, numerical examples are presented demonstrating that a p-value can, as a practical matter, give you a really different answer than the one that you want.

scholarly journals COVID-19 in a Rural Community: Outbreak Dynamics, Contact Tracing and Environmental RNA

2020 ◽  
Author(s):  
Isabel G. Fernández de Mera ◽  
Francisco J. Rodríguez del Río ◽  
José de la Fuente ◽  
Marta Pérez Sancho ◽  
Dolores Hervas ◽  
...  
Keyword(s):  
Rural Community ◽  
Public Service ◽  
Contact Tracing ◽  
Rt Pcr ◽  
Rna Surveillance ◽  
Petrol Station ◽  
Early Testing ◽  
Resource Deployment ◽  
The Village ◽  
Close Contacts

Background: Since March 2020, Spain is severely hit by the ongoing pandemic of coronavirus disease 19 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Understanding and disrupting the early transmission dynamics of the infection is crucial for impeding sustained transmission. Methods: We recorded all COVID-19 cases and traced their contacts in an isolated rural community. We also sampled 10 households, 6 public service sites and the wastewater from the village sewage for environmental SARS-CoV-2 RNA. Results: The first village patient diagnosed with COVID-19-compatible symptoms occurred on March 3, 2020, twelve days before lockdown. A peak of 39 cases occurred on March 30. By May 15, the accumulated number of symptomatic cases was 53 (6% of the population), of which only 22 (41%) had been tested and confirmed by RT-PCR as SARS-CoV-2 infected, including 16 hospitalized patients. Contacts (n=144) were six times more likely to develop symptoms. Environmental sampling detected SARS-CoV-2 RNA in two households with known active cases and in two public service sites: the petrol station and the pharmacy. Samples from other sites and the wastewater tested negative. Conclusions: The low proportion of patients tested by RT-PCR calls for urgent changes in disease management. We propose that early testing of all cases and their close contacts would reduce infection spread, reducing the disease burden and fatalities. In a context of restricted testing, environmental RNA surveillance might prove useful for early warning and to identify high-risk settings enabling a targeted resource deployment.

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