A model for determining optimal frequency and fraction of population to be tested, for cost-effective surveillance testing for SARS-CoV2: algorithm development (Preprint)

2020 ◽  
Author(s):  
Jonathan Silver
Keyword(s):  
Cost Effectiveness ◽  
False Negative ◽  
False Negative Rate ◽  
Cost Effective ◽  
Test Frequency ◽  
Optimal Test ◽  
Current Spread ◽  
Graphical Interfaces ◽  
Prior Infection

BACKGROUND Because Covid19 can be asymptomatic, surveillance testing with isolation of those who test positive can reduce spread. But what fraction of a population should be tested, how often, and how long should surveillance testing continue as vaccination progresses? OBJECTIVE Develop a model that allows determination of extent and frequency of testing that optimize cost-effectiveness, and time after which surveillance testing ceases to be cost-effective. METHODS Free software from Illumina (Analytica 101) was used to make a model that runs on personal computers. Graphical interfaces demonstrate how the model reaches its conclusions and allow users with little programming experience to choose values for parameters that vary in different circumstances. RESULTS Optimal test frequency and fraction of a population to be tested depend on test cost, test sensitivity, false negative rate, delay (if any) between testing and isolation of those who test positive, and rate of compliance with isolation. Overall cost-effectiveness and optimal duration of testing depend critically on the value placed on saving a life, effective spread rate (R_eff) when surveillance testing is instituted, and fraction of a population already immune due to prior infection or vaccination. CONCLUSIONS For current spread rates (R_eff ca 1.2-1.5) and percent immune (ca 10%), overall cost-effectiveness generally requires value per life saved to be greater than $100,000. Optimal test frequency and fraction tested range from days to months, and ca .1 to 1, respectively, for different types of tests (antigen, pcr) currently on the market.

scholarly journals Distribution of pathologic smear results and histopathologic agreement in precancerous cervical lesions

2020 ◽  
pp. 1
Author(s):  
Eser Colak ◽  
Esra Zeynep Coskunoglu
Keyword(s):  
Pap Smear ◽  
False Positive Rate ◽  
False Negative ◽  
False Negative Rate ◽  
Young Patients ◽  
Cost Effective ◽  
High Grade ◽  
Cervical Lesions ◽  
Histopathological Correlation ◽  
Epithelial Lesions

<p><strong>OBJECTIVES:</strong> The accuracy of the Papanicolau smear test is very important in cervical cancer which is preventable cancer. In this study, we aimed to investigate the distribution of smear results and cyto-histopathological correlation and agreement in biopsies.</p><p><strong>STUDY DESIGN:</strong> A retrospective study was performed at the gynecology obstetrics and pathology department of Baskent University Konya Application and Research Hospital, over a 5-year period. The histopathology results of 89 patients who underwent colposcopic biopsy from 273 patients with pathologic Pap smear results were examined. The histopathologic results and pathologic Pap smear results were compared and the compatibility between them was examined.</p><p><strong>RESULTS:</strong> Data records were collected for 11,191 women. Overall, the prevalence of cytologic abnormalities was 2.43%. The cytohistopathologic correlation in epithelial lesions was 56% and was statistically significant. In glandular lesions, normal biopsy results were reported in 93% of AGC-NOS cytology results, whereas there was a 100% malignancy correlation with AGC-FN cytology results. In terms of detecting low and high-grade lesions, the false-negative rate was 12% and the false-positive rate was 17%.</p><p><strong>CONCLUSION:</strong> In conclusion, Pap smears can be less cost-effective and easily accessible method. While conservative treatment is appropriate in young patients because of possible regression even in high-grade lesions; in older patients, it should not be hesitated to get biopsy when a suspicious clinic is present.</p>

scholarly journals Intraoperative Margin Assessment by Frozen Section Enables Cost-Effective, Safe, One-Step Breast Conservation

2018 ◽  
Vol 4 (Supplement 3) ◽  
pp. 2s-2s ◽  
Author(s):  
Gaurav Agarwal ◽  
S. Chaitra ◽  
M. Sabaretnam ◽  
Anjali Mishra ◽  
Vinita Agrawal ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Frozen Section ◽  
False Negative ◽  
Operating Time ◽  
Breast Conservation ◽  
Cost Effective ◽  
Single Stage ◽  
Margin Assessment ◽  
One Step ◽  
The Cost

Purpose Acceptance of breast conservation surgery (BCS) is low among Indian women, as many perceive mastectomy to be a superior cost-effective surgical option. Obtaining uninfiltrated margins is vital during BCS. The need for reoperation to re-excise infiltrated surgical margins adds to the cost of treatment, which further reduces the acceptability of BCS. Intraoperative frozen-section (FS) histology assessment of margins provides an opportunity to carry out a single-stage, safe BCS; however, the utility of FS margin assessment remains unproven because of its perceived low accuracy, added costs, and longer operating time. In this retrospective analysis, we studied the accuracy of FS for margin assessment, its ability to help avoid reoperations, and the cost effectiveness of one-step BCS using FS compared with margin assessment using postoperative paraffin section (PS) histopathology. Methods Patients who underwent BCS during 2011 to 2015 with a minimum 1-year follow-up were included. All patients underwent intraoperative FS and postoperative PS margin assessment. All infiltrated margins were re-excised. Repeatedly infiltrated re-excised margins or extensive ductal carcinoma in situ necessitated mastectomy in few patients. We evaluated the accuracy of FS in the detection of margin infiltration, thereby allowing single-stage, safe BCS. The cost effectiveness of two strategies for the management of infiltrated margins, namely intraoperative FS and single-stage margin excision/mastectomy and postoperative PS and reoperation (two-step) surgery, were compared. The cost per saved reoperation with the use of intraoperative FS was calculated using actual hospital costs and various—lower and higher—cost assumptions. Results On the basis of intraoperative FS margin assessment, 18 (12.5%) of 144 patients required margin(s) re-excision and another nine patients (6.2%) needed mastectomy. Twenty-six patients (18%) were thus spared reoperation with the use of FS. Two patients (1.4%) with uninfiltrated margins on FS—false-negative FS—needed reoperation for infiltrated margins that were detected on PS. Considering the costs (144 FS and two reoperations) and savings (26 avoided reoperations), use of FS was 1.15 times more cost effective than PS for achieving uninfiltrated margins. Cost incurred per saved reoperation by FS was INR 5,438 (approximately $81 USD). Sensitivity analysis using various cost assumptions revealed similar results. Conclusion Use of FS can facilitate single-step, oncologically safe BCS by avoiding reoperation in those patients with infiltrated margins and is cost effective compared with postoperative margin assessment using PS alone. FS can thus help in improving the acceptability of BCS, even in those patients with relatively large tumors for whom the possible need and cost of reoperation are major deterrents against BCS. AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST The following represents disclosure information provided by authors of this manuscript. All relationships are considered compensated. Relationships are self-held unless noted. I = Immediate Family Member, Inst = My Institution. Relationships may not relate to the subject matter of this manuscript. For more information about ASCO's conflict of interest policy, please refer to www.asco.org/rwc or ascopubs.org/jco/site/ifc . No COIs from the authors.

scholarly journals Frozen Section Diagnosis: Accuracy and Errors; with Emphasis on Reasons for Discordance

2021 ◽  
Vol 8 (2) ◽  
pp. A33-38
Author(s):  
Roopam Kishore Gidwani ◽  
Falguni Jay Goswami ◽  
Arpan Mehta ◽  
Nirali V Shah ◽  
Shobhana Ashok Prajapati ◽  
...  
Keyword(s):  
Sampling Error ◽  
Frozen Section ◽  
False Positive Rate ◽  
False Negative ◽  
False Negative Rate ◽  
Paraffin Section ◽  
Cost Effective ◽  
Final Diagnosis ◽  
Frozen Section Diagnosis ◽  
Final Histological Diagnosis

Background: Frozen section is a multistep process involving surgical resection, intraoperative preparation of slides and their microscopic examination.  It is important to   assess concordant, discordant and deferred diagnosis rates from intra-operative frozen section diagnosis with final diagnosis on paraffin section and to determine the reasons for discordance. An integral part of quality assurance in surgical pathology entails the correlation of intra-operative frozen section diagnosis with final diagnosis on permanent section.  Methods:  A retrospective analysis of 117 cases of frozen section biopsy was carried out which were reported in the Histopathology department between July 2007 to June 2012.  The correlation between the frozen section diagnosis with final histological diagnosis was performed in order to check the accuracy of the technique.  The number and type of discrepancies were compared, causes for the discrepancies were analyzed in order to decrease the avoidable errors and improve on the frozen section diagnoses.   Results:  The overall accuracy of frozen section diagnoses over 5years was 90.60% with false positive rate of 0.85%, false negative rate of 6.84% and 1.71% of deferred diagnosis. Sensitivity was 87.69% and Specificity was 98%.  The discrepancies were mainly due to the interpretation error, sampling error and technical artefacts. Conclusions:  Gross inspection, sampling by pathologist, frozen section complemented with cytological and histological review and cooperation between consultants can avoid certain limitations and provide rapid, reliable, cost effective information necessary for optimum patient care.

Determination of false negative rate in fine-needle aspiration of prostate

Urology ◽  
1989 ◽  
Vol 34 (2) ◽  
pp. 73-75 ◽  
Author(s):  
Michael W. Stanley ◽  
Per Olov Hedlund ◽  
Lars Rönstrom ◽  
Pier Luigi Esposti ◽  
Torsten Löwhagen
Keyword(s):  
Fine Needle Aspiration ◽  
False Negative ◽  
False Negative Rate ◽  
Needle Aspiration ◽  
Fine Needle ◽  
Negative Rate

scholarly journals Determination of the HER2 amplification status by in situ fluorescent hybridization and concordance with immunohistochemistry for breast cancer samples in Colombia

2013 ◽  
pp. 108-114
Author(s):  
Adriana Plata ◽  
María Mercedes Torres ◽  
Rocío López ◽  
Rafael E. Andrade
Keyword(s):  
Breast Cancer ◽  
False Negative ◽  
False Negative Rate ◽  
Her2 Status ◽  
Santa Fe ◽  
Her2 Amplification ◽  
The Status ◽  
Positive Results

Objectives: To determine the status of the HER2 amplification in Breast cancer performed in peripheral laboratories in Colombia by immunohistochemistry and its comparison with central laboratories and the FISH status. Methods: Four thousand one hundred and five cases referred for the determination of the HER2 status by FISH and/or IHQ to the Department of Pathology of the Fundacion Santa Fe were studied. The analysis included correlation between the IHQ HER2 score submitted by the peripheral laboratory (PL), the HER2 score emitted in the LC and the FISH studies performed in the central laboratory (CL). Results: two thousand five hundred and eight HER2 IHQ studies were performed in the (CL), using the Dako Herceptest. With the following results: 68.2 % negative (0-1+); 16.4% indeterminate (2+); 15.3% 3+ and 2.3 % not adequate. 1360/ 1719 cases studied by FISH came from the (PL), and 329 (19.1%) from the (Lc). Comparing the IHQ score emitted by the PL and the positive FISH status showed: 6/28 0+ were positive (21.4%); 7/31 1+ (22.5%); 397/1.240 2+ (32.8%) and 74/91 3+ (81.3%). In the CL the results were 1/9 0+ (11.1%); 3/18 1+ (16.7%); 154/292 2+ (53.0%); and 9/9 3+ (100%). Only 1/4 negative cases (0/1+) was in house. Conclusion: The false negative rate (22.0%), and false positive results (18.7%), of the HER2 status performed by IHQ in peripheral laboratories in Colombia is unacceptable high as well as the inadequacy of tissue indicating that pre-analytical factors have to be improved in Colombia in order to get optimal results

Determination of Listeria in Dairy and Environmental Samples: Comparison of a Cultural Method and a Colorimetric Nucleic Acid Hybridization Assay

1993 ◽  
Vol 56 (7) ◽  
pp. 581-584 ◽  
Author(s):  
BERNHARD URL ◽  
ALI HEITZER ◽  
ERNST BRANDL
Keyword(s):  
Nucleic Acid ◽  
Environmental Samples ◽  
False Negative ◽  
False Negative Rate ◽  
Nucleic Acid Hybridization ◽  
Hybridization Assay ◽  
Sample Enrichment ◽  
Density Values ◽  
The Mean

The efficiency of the International Dairy Federation (IDF) Listeria detection method (IDF Standard 143:1990) was compared to that of a colorimetric nucleic acid hybridization assay. Out of 250 naturally contaminated cheese and environmental samples tested, the IDF method revealed 153 and the Gene-Trak assay 144 positive samples, respectively. Hence, the Gene-Trak assay gave a false-negative rate of 5.9%. False-positive samples could not be detected. When Oxford and LPM agar were compared for suitability as the streaking medium for the Gene-Trak assay, more satisfactory results were obtained with the Oxford agar. Both the overall number of positive samples and the mean optical density values of the Gene-Trak-positive samples were higher with Oxford than with LPM agar. The extension of sample enrichment time from 1 d (Gene-Trak-assay), and 2 d (IDF method), respectively, to 7 d resulted in a small increase in the number IDF method-positive samples but led to a drastic decrease in the number of Gene-Trak-positive samples.

scholarly journals Three ounce Water Swallow Test versus Fiberoptic Endoscopic Evaluation of Swallowing for Evaluation of Laryngeal Aspiration

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
S Ahmed ◽  
S Bassiouny ◽  
N Hafez ◽  
H Ghandour ◽  
M Salah
Keyword(s):  
False Negative ◽  
False Negative Rate ◽  
Oral Feeding ◽  
Screening Tools ◽  
Endoscopic Evaluation ◽  
University Hospitals ◽  
Stroke Patients ◽  
Diagnostic Categories ◽  
Negative Rate

Abstract Background Screening of dysphagia by 3 ounce water swallow test (WST) is one of the most common screening tools especially among stroke patients worldwide and it is very important to avoid serious complications as pneumonia, guide starting oral alimentation. Aim of the work to compare the effectiveness of 3 ounce WST to the FEES results in determination of aspiration in order to guide oral feeding recommendation. Patients and Method This study included 39 patients recruited from the Phoniatric out-patient clinics of Ain Shams University Hospitals and Banha University Hospitals. They were subjected to doing 3 ounce WST after complete assessment according to protocol of dysphagia Ain Shams University and then doing FEES which used as the gold standard to compare the results of 3 ounce WST. Results Sensitivity of 3 ounce WST was 72%, specificity was 100%, false negative rate was 28% among patients of different diagnostic categories while Sensitivity of 3 ounce WST was 87.5 %, specificity was 100%, false negative rate was 12.5 % among stroke patients. Conclusion Although being simple, inexpensive and quick to perform, the 3 ounce WST is not sensitive enough to detect cases of silent aspirations. A large false negative rate exists. In addition, it does not differentiate between penetration or aspiration, if cough occurs, and thus not truly helpful in oral feeding recommendations.

scholarly journals Intelligent Mirai Malware Detection for IoT Nodes

Electronics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1241
Author(s):  
Tarun Ganesh Palla ◽  
Shahab Tayeb
Keyword(s):  
Machine Learning ◽  
Learning Algorithm ◽  
False Negative ◽  
Malware Detection ◽  
False Negative Rate ◽  
Cost Effective ◽  
User Privacy ◽  
Digital World ◽  
Iot Devices ◽  
Artificial Neural Network Ann

The advancement in recent IoT devices has led to catastrophic attacks on the devices resulting in breaches in user privacy and exhausting resources of various organizations, so that users and organizations expend increased time and money. One such harmful malware is Mirai, which has created worldwide recognition by impacting the digital world. There are several ways to detect Mirai, but the Machine Learning approach has proved to be accurate and reliable in detecting malware. In this research, a novel-based approach of detecting Mirai using Machine Learning Algorithm is proposed and implemented in Matlab and Python. To evaluate the proposed approaches, Mirai and Benign datasets are considered and training is performed on the dataset comprised of a Training set, Cross-Validation set and Test set using Artificial Neural Network (ANN) consisting of neurons in the hidden layer, which provides consistent accuracy, precision, recall and F-1 score. In this research, an accurate number of hidden layers and neurons are chosen to avoid the problem of Overfitting. This research provides a comparative analysis between ANN and Random Forest models of the dataset formed by merging Mirai and benign datasets of the Mirai malware detection pertaining to seven IoT devices. The dataset used in this research is “N-BaIoT” dataset, which represents data in the features infected by Mirai Malware. The results are found to be accurate and reliable as the best performance was achieved with an accuracy of 92.8% and False Negative rate of 0.3% and F-1 score of 0.99. The expected outcomes of this project, include major findings towards cost-effective Learning solutions in detecting Mirai Malware strains.

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