811 WHETHER 10 WATER SWALLOWS NECESSARY TO OBTAIN REPRODUCIBLE RESULTS OF HIGH-RESOLUTION OESOPHAGEAL MANOMETRY?

2021 ◽  
Vol 34 (Supplement_1) ◽  
Author(s):  
Sergey Morozov ◽  
Vasily Kropochev ◽  
Alexey Artemov
Keyword(s):  
High Resolution ◽  
Diagnostic Accuracy ◽  
False Positive ◽  
Roc Analysis ◽  
Characteristic Curve ◽  
False Negative ◽  
Ratio Test ◽  
Type I ◽  
Primary Position ◽  
Oesophageal Manometry

Abstract   Not less than ten wet swallows assessment in the primary test position is recommended by Chicago classification 4.0 for high-resolution oesophageal manometry (HREM); however, the required number of measurements are not sufficiently supported. Aim to evaluate the number of wet swallows necessary for correct interpretation of the results of lower esophageal sphincter integrated relaxation pressure (IRP) with low probability of type I and II errors. Methods Patients referred to perform HREM were enrolled. Solid-state 10Fr catheter and Solar (Laborie) software were used. Minimum 10 swallows by 5 mL water were obtained. These were analysed for cumulative means of IRP after 1…9 measurements. Conclusion made at each moment was compared with one based on 10 measurements. The results were characterized as true/false positive/negative for calculation of diagnostic accuracy. To exclude sample influence, Monte-Carlo simulation of sequential decision-making was performed with the use of sequential probability ratio test. Association of the diagnostic accuracy from recall was studied with the use of receiver operating characteristic curve (ROC) analysis. Results One hundred subjects were enrolled (25 with disorders of EGJ outflow). During the simulation, the probability of matching the decisions based on the 10 measurements and lower number of them was high. ROC analysis showed that actual probability to obtain false-positive results was twice as lower then ‘allowed’ rate of 5%. The probability to make false-negative results did not exceed 10% in any number of measurements. The probability that the conclusions made after 2 and after 10 measurements match was 0.9584 in those with disorders of EGJ outflow and 0.9652 in those without (figure 1). Conclusion The standard number of measurements required to support the presence of disorders of EGJ outflow during evaluation of 5 mL wet swallows in the primary position is excessive. Values of the IRP after 2 swallows allows to make similar decision to that after 10 swallows with >95% probability. This allows to reduce the number of wet swallows to assess in the primary position and save time for assessments in alternative position or perform provocation tests.

Methylene Blue as a Diagnosis and Screening Tool for Oral Cancer and Precancer

2020 ◽  
pp. 019459982094768
Author(s):  
Se Hwan Hwang ◽  
Sung Won Kim ◽  
Eun A. Song ◽  
Junuk Lee ◽  
Do Hyun Kim
Keyword(s):  
Methylene Blue ◽  
Oral Cancer ◽  
Diagnostic Accuracy ◽  
False Positive ◽  
Characteristic Curve ◽  
False Positive Rate ◽  
False Negative ◽  
High Sensitivity ◽  
Summary Receiver Operating Characteristic ◽  
True Negative

Objectives To evaluate the accuracy of methylene blue (MB) for diagnosing oral cancer and precancer. Data Sources PubMed, Cochrane Database, Embase, Web of Science, SCOPUS, and Google Scholar. Review Methods Two authors working independently reviewed 6 databases from their dates of inception until April 2020. Studies exploring oral mucosal disorders as detected by MB were assessed. True-positive, true-negative, false-positive, and false-negative data were extracted for each study. Methodological quality was evaluated with the Quality Assessment of Diagnostic Accuracy Studies tool (v 2). Results Seven prospective and retrospective studies (N = 493) were included. The diagnostic odds ratio of MB was 20.017 (95% CI, 10.65-37.63, I2 = 23%). The area under the summary receiver operating characteristic curve was 0.699. Sensitivity was 0.903 (95% CI, 0.84-0.94, I2 = 54%), and specificity was 0.68 (95% CI, 0.60-0.75, I2 = 0%). The correlation between the sensitivity and the false-positive rate was –0.17, indicating an absence of heterogeneity. Conclusions Regarding diagnostic accuracy, MB had high sensitivity but low specificity, suggesting that it cannot be recommended as a replacement for the currently used standard of a scalpel biopsy with histologic assessment. Instead, it should be used as an adjunct to conventional assessment because of its low toxicity and price.

Comparison of Narrowband Imaging and White-Light Endoscopy for Diagnosis and Screening of Nasopharyngeal Cancer

2021 ◽  
pp. 019459982110296
Author(s):  
Do Hyun Kim ◽  
Min Hyeong Lee ◽  
Seulah Lee ◽  
Sung Won Kim ◽  
Se Hwan Hwang
Keyword(s):  
Diagnostic Accuracy ◽  
White Light ◽  
False Positive ◽  
Characteristic Curve ◽  
False Positive Rate ◽  
False Negative ◽  
Nasopharyngeal Cancer ◽  
True Negative ◽  
White Light Endoscopy ◽  
Narrowband Imaging

Objectives We compared the diagnostic accuracies of narrowband imaging and white-light endoscopy in the detection of nasopharyngeal cancer. Data Sources Six databases (PubMed, Cochrane Database, Embase, Web of Science, SCOPUS, and Google Scholar). Review Methods The 6 databases were thoroughly reviewed by 2 authors (working independently) from their dates of inception to December 2019. Nasopharyngeal mucosal or vascular changes detected by narrowband imaging were compared to those detected by white-light endoscopy. The authors extracted true-positive, true-negative, false-positive, and false-negative parameters for each study. Methodological quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies version 2 tool. The extent of interrater agreement was assessed. Results Eighteen prospective or retrospective studies were included. The diagnostic odds ratio of narrowband imaging was 77.560 (95% confidence interval [CI], 37.424-160.739). The area under the summary receiver operating characteristic curve was 0.926. The sensitivity, specificity, and negative predictive value were 0.871 (95% CI, 0.808-0.915), 0.905 (95% CI, 0.816-0.953), and 0.955 (95% CI, 0.906-0.979), respectively. The correlation between sensitivity and the false-positive rate was 0.284, indicating that heterogeneity was absent. Narrowband imaging exhibited moderate interrater reliability (0.7037; 95% CI, 0.6558-0.746). Subgroup analysis showed that vascular patterns revealed by endoscopy in a screened subgroup were significantly more diagnostically accurate than mucosal patterns used for surveillance of a recurrent cancer subgroup. Conclusions Narrowband imaging exhibits high diagnostic accuracy and should be used in the diagnostic workup of nasopharyngeal cancer. However, further studies are necessary to confirm our results.

The role of serum periostin in the diagnosis of asthma: A meta-analysis

2020 ◽  
Vol 41 (4) ◽  
pp. 240-247
Author(s):  
Lei Yang ◽  
Qingtao Zhao ◽  
Shuyu Wang
Keyword(s):  
Diagnostic Accuracy ◽  
Meta Analysis ◽  
Characteristic Curve ◽  
False Negative ◽  
Summary Receiver Operating Characteristic ◽  
True Negative ◽  
Negative Results ◽  
Noninvasive Biomarker ◽  
Sensitivity Specificity ◽  
Serum Periostin

Background: Serum periostin has been proposed as a noninvasive biomarker for asthma diagnosis and management. However, its accuracy for the diagnosis of asthma in different populations is not completely clear. Methods: This meta-analysis aimed to evaluate the diagnostic accuracy of periostin level in the clinical determination of asthma. Several medical literature data bases were searched for relevant studies through December 1, 2019. The numbers of patients with true-positive, false-positive, false-negative, and true-negative results for the periostin level were extracted from each individual study. We assessed the risk of bias by using Quality Assessment of Diagnostic Accuracy Studies 2. We used the meta-analysis to produce summary estimates of accuracy. Results: In total, nine studies with 1757 subjects met the inclusion criteria. The pooled estimates of sensitivity, specificity, and diagnostic odds ratios for the detection of asthma were 0.58 (95% confidence interval [CI], 0.38‐0.76), 0.86 (95% CI, 0.74‐0.93), and 8.28 (95% CI, 3.67‐18.68), respectively. The area under the summary receiver operating characteristic curve was 0.82 (95% CI, 0.79‐0.85). And significant publication bias was found in this meta‐analysis (p = 0.39). Conclusion: Serum periostin may be used for the diagnosis of asthma, with moderate diagnostic accuracy.

scholarly journals A new criterion for the alarm point using a combination of waveform amplitude and onset latency in Br(E)-MsEP monitoring in spine surgery

2018 ◽  
Vol 29 (4) ◽  
pp. 435-441 ◽  
Author(s):  
Kazuyoshi Kobayashi ◽  
Kei Ando ◽  
Ryuichi Shinjo ◽  
Kenyu Ito ◽  
Mikito Tsushima ◽  
...  
Keyword(s):  
Spine Surgery ◽  
Predictive Value ◽  
False Positive ◽  
Roc Analysis ◽  
False Positive Rate ◽  
False Negative ◽  
False Negative Rate ◽  
High Rate ◽  
Motor Deficit ◽  
Onset Latency

OBJECTIVEMonitoring of brain evoked muscle-action potentials (Br[E]-MsEPs) is a sensitive method that provides accurate periodic assessment of neurological status. However, occasionally this method gives a relatively high rate of false-positives, and thus hinders surgery. The alarm point is often defined based on a particular decrease in amplitude of a Br(E)-MsEP waveform, but waveform latency has not been widely examined. The purpose of this study was to evaluate onset latency in Br(E)-MsEP monitoring in spinal surgery and to examine the efficacy of an alarm point using a combination of amplitude and latency.METHODSA single-center, retrospective study was performed in 83 patients who underwent spine surgery using intraoperative Br(E)-MsEP monitoring. A total of 1726 muscles in extremities were chosen for monitoring, and acceptable baseline Br(E)-MsEP responses were obtained from 1640 (95%). Onset latency was defined as the period from stimulation until the waveform was detected. Relationships of postoperative motor deficit with onset latency alone and in combination with a decrease in amplitude of ≥ 70% from baseline were examined.RESULTSNine of the 83 patients had postoperative motor deficits. The delay of onset latency compared to the control waveform differed significantly between patients with and without these deficits (1.09% ± 0.06% vs 1.31% ± 0.14%, p < 0.01). In ROC analysis, an intraoperative 15% delay in latency from baseline had a sensitivity of 78% and a specificity of 96% for prediction of postoperative motor deficit. In further ROC analysis, a combination of a decrease in amplitude of ≥ 70% and delay of onset latency of ≥ 10% from baseline had sensitivity of 100%, specificity of 93%, a false positive rate of 7%, a false negative rate of 0%, a positive predictive value of 64%, and a negative predictive value of 100% for this prediction.CONCLUSIONSIn spinal cord monitoring with intraoperative Br(E)-MsEP, an alarm point using a decrease in amplitude of ≥ 70% and delay in onset latency of ≥ 10% from baseline has high specificity that reduces false positive results.

scholarly journals Incorporation of Second-Tier Biomarker Testing Improves the Specificity of Newborn Screening for Mucopolysaccharidosis Type I

2020 ◽  
Vol 6 (1) ◽  
pp. 10 ◽  
Author(s):  
Dawn S. Peck ◽  
Jean M. Lacey ◽  
Amy L. White ◽  
Gisele Pino ◽  
April L. Studinski ◽  
...  
Keyword(s):  
Newborn Screening ◽  
False Positive ◽  
Dermatan Sulfate ◽  
False Positive Rate ◽  
False Negative ◽  
Type I ◽  
Mucopolysaccharidosis Type ◽  
Mucopolysaccharidosis Type I ◽  
Second Tier ◽  
Mps I

Enzyme-based newborn screening for Mucopolysaccharidosis type I (MPS I) has a high false-positive rate due to the prevalence of pseudodeficiency alleles, often resulting in unnecessary and costly follow up. The glycosaminoglycans (GAGs), dermatan sulfate (DS) and heparan sulfate (HS) are both substrates for α-l-iduronidase (IDUA). These GAGs are elevated in patients with MPS I and have been shown to be promising biomarkers for both primary and second-tier testing. Since February 2016, we have measured DS and HS in 1213 specimens submitted on infants at risk for MPS I based on newborn screening. Molecular correlation was available for 157 of the tested cases. Samples from infants with MPS I confirmed by IDUA molecular analysis all had significantly elevated levels of DS and HS compared to those with confirmed pseudodeficiency and/or heterozygosity. Analysis of our testing population and correlation with molecular results identified few discrepant outcomes and uncovered no evidence of false-negative cases. We have demonstrated that blood spot GAGs analysis accurately discriminates between patients with confirmed MPS I and false-positive cases due to pseudodeficiency or heterozygosity and increases the specificity of newborn screening for MPS I.

Simple modifications of three routine in vitro tests of thyroid function.

1976 ◽  
Vol 22 (10) ◽  
pp. 1715-1718 ◽  
Author(s):  
R W Pain
Keyword(s):  
Diagnostic Accuracy ◽  
Thyroid Function ◽  
False Positive ◽  
Reference Range ◽  
False Negative ◽  
Work Load ◽  
In Vitro Tests ◽  
Free Thyroxine Index ◽  
Total Thyroxine

Abstract Semi-automation of equipment and simple modifications of technique reduced the work load without loss of diagnostic accuracy for three commonly used in vitro tests of thyroid function (total thyroxine, thyrobinding index, and free thyroxine index). Major innovations were the use of serum standards for all tests and having each duplicate for tests performed by a different technician. Attention is drawn to the false-positive and false-negative errors that occur when the 95% euthyroid limits is the sole reference range used.

Usefulness of Nasal Endoscopy for Diagnosing Patients With Chronic Rhinosinusitis: A Meta-Analysis

2019 ◽  
Vol 34 (2) ◽  
pp. 306-314
Author(s):  
Do Hyun Kim ◽  
Youngjun Seo ◽  
Kyung Min Kim ◽  
Seoungmin Lee ◽  
Se Hwan Hwang
Keyword(s):  
Diagnostic Accuracy ◽  
Chronic Rhinosinusitis ◽  
Sensitivity And Specificity ◽  
Meta Analysis ◽  
Characteristic Curve ◽  
False Negative ◽  
Nasal Endoscopy ◽  
Summary Receiver Operating Characteristic ◽  
True Negative ◽  
Endoscopic Score

Background We evaluated the accuracy of nasal endoscopy in diagnosing chronic rhinosinusitis (CRS) compared with paranasal sinus computed tomography (CT). Methods Two authors independently searched the 5 databases (PubMed, SCOPUS, Embase, the Web of Science, and the Cochrane database) up to March 2019. For all included studies, we calculated correlation coefficients between the endoscopic and CT scores. We extracted data on true-positive and false-positive and true-negative and false-negative results. Methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool (version 2). Results We included 16 observational or retrospective studies. A high correlation ( r = .8543; 95% confidence interval [CI] [0.7685–0.9401], P < .0001, I2 = 76.58%) between endoscopy and CT in terms of the diagnostic accuracy for CRS was apparent. The odds ratio (Lund–Kennedy endoscopic score ≥1) was 7.915 (95% CI [4.435–14.124]; I2 = 28.361%). The area under the summary receiver operating characteristic curve was 0.765. The sensitivity and specificity were 0.726 (95% CI [0.584–0.834]) and 0.767 (95% CI [0.685–0.849]), respectively. However, high interstudy heterogeneity was evident given the different endoscopic score thresholds used (Lund–Kennedy endoscopic score ≥1 vs 2). In a subgroup analysis of studies using a Lund–Kennedy endoscopic score threshold ≥2, the area under the summary curve was 0.881, and the sensitivity and specificity were 0.874 (95% CI [0.783–0.930]) and 0.793 (95% CI [0.366–0.962]), respectively. Conclusion Nasal endoscopy is a useful diagnostic tool; the Lund–Kennedy score was comparable with that of CT.

scholarly journals High resolution analysis of cervical cells--a progress report.

1977 ◽  
Vol 25 (7) ◽  
pp. 689-695 ◽  
Author(s):  
R S Poulsen ◽  
L H Oliver ◽  
R L Cahn ◽  
C Louis ◽  
G Toussaint
Keyword(s):  
High Resolution ◽  
False Positive ◽  
False Negative ◽  
Error Rates ◽  
Cell Segmentation ◽  
Negative Error ◽  
False Negative Error ◽  
High Resolution Analysis ◽  
Resolution Analysis ◽  
Cervical Cells

This paper presents preliminary results of research toward the development of a high resolution analysis stage for a dual resolution image processing-based prescreening device for cervical cytology. Experiments using both manual and automatic methods for cell segmentation are described. In both cases, 1500 cervical cells were analyzed and classified as normal or abnormal (dysplastic or malignant) using a minimum Mahalanobis distance classifier with eight subclasses of normal cells, and five subclasses of abnormal cells. With manual segmentation, false positive and false negative error rates of 2.98 and 7.73% were obtained. Similar experiments using automatic cell segmentation methods yielded false positive and false negative error rates of 3.90 and 11.56%, respectively. In both cases, independent training and testing data were used.

scholarly journals High Diagnostic Accuracy of Antigen Microarray for Sensitive Detection of Hepatitis C Virus Infection

2008 ◽  
Vol 54 (2) ◽  
pp. 424-428 ◽  
Author(s):  
Jung-ah Kwon ◽  
Hyeseon Lee ◽  
Kap N o Lee ◽  
Kwangchun Chae ◽  
Seram Lee ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Detection Limit ◽  
Diagnostic Accuracy ◽  
False Positive ◽  
Sol Gel ◽  
False Negative ◽  
Screening Method ◽  
Confirmatory Test ◽  
Specificity And Sensitivity

Abstract Background: Hepatitis C virus (HCV) can be transmitted through blood transfusion. Screening ELISA, the most widely used method for HCV diagnosis, sometimes yields false-positive and false-negative results, so a confirmatory test is used. This secondary testing is labor-intensive and expensive, and thus is impractical for massive blood bank screening. Therefore, a new massive screening method with high accuracy is needed for sensitive and specific detection of HCV. Methods: With sol-gel material, we designed novel antigen microarray in 96-well plates for HCV detection. Each individual well was spotted with 4 different HCV antigens. We used this new system to test 154 patient serum samples previously tested for HCV by ELISA (87 HCV positive and 67 HCV negative) (HCV EIA3.0, ABBOTT). We assessed the detection limit of our microarray system with the use of serial 10-fold dilutions of an HCV-positive sample. Results: Our microarray assay was reproducible and displayed higher diagnostic accuracy (specificity) (98.78%) than did the ELISA (81.71%). Our method yielded significantly fewer false-positive results than did the ELISA. The detection limit of our assay was 1000 times more sensitive than that of the ELISA. In addition, we found this novel assay technology to be compatible with the currently employed automated methods used for ELISA. Conclusion: We successfully applied the sol-gel–based protein microarray technology to a screening assay for HCV diagnosis with confirmatory test-level accuracy. This new, inexpensive method will improve the specificity and sensitivity of massive sample diagnosis.

Trial Sequential Analysis in Meta-Analyses of Maintenance Therapies for Multiple Myeloma.

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2975-2975
Author(s):  
Branko Miladinovic ◽  
Ambuj Kumar ◽  
Rahul Mhaskar ◽  
Helen Mahoney ◽  
Keith Wheatley ◽  
...  
Keyword(s):  
Randomized Controlled Trials ◽  
Risk Ratio ◽  
False Positive ◽  
False Negative ◽  
Trial Sequential Analysis ◽  
Controlled Trials ◽  
Type I ◽  
Randomized Controlled ◽  
Meta Analyses ◽  
Ratio Reduction

Abstract Abstract 2975 Background: Meta-analyses (MAs) with few participants (i.e. small number of primary studies) are at risk of producing random errors and consequently overestimating treatment effects. With insufficient information the risk of obtaining a false positive result (type I error) increases, which may lead to false conclusions. Trial sequential analysis (TSA) has been proposed as a method to ascertain whether results of MAs are conclusive (true vs. false positive, true vs. false negative). It adjusts for the risk of random error by constructing monitoring boundaries under the sample size necessary to conclude significant treatment effect. In TSA, the information size is calculated based on a pre-specified event rate in the control group, a minimum intervention effect (risk ratio reduction), and a desired maximum risk of type I error α and type II error β. Here we apply TSA on MAs of randomized controlled trials of maintenance therapies in the management of multiple myeloma. Methods: A comprehensive literature search of MEDLINE (PubMed), the Cochrane Central Register of Controlled Trials (CENTRAL), and meetings abstracts from American Society of Hematology, American Society of Clinical Oncology, European Society for Medical Oncology and European Hematology Association was undertaken to identify all phase III randomized controlled trials (RCTs) of maintenance therapy published until July 2012. We extracted data on overall survival and progression-free survival comparing treatments that could be pooled in random effects meta-analysis. We performed TSA for the apriori diversity-adjusted information size (APDIS) under risk ratio reduction of 20% and 25%. The information size was adjusted for between-study trial diversity, which is defined as the total relative variance expansion changing from a fixed effect into a random effects meta-analysis. We used two-sided α = 5% and 1 – β = 80% power. All analyses were done in Stata 11.2 using metacumbounds command. Results: Nine separate meta-analyses (18 randomized controlled trials) met the inclusion criteria (Table 1). The median number of patients was 1193 (range 351–2824) and median diversity 0% (range 0%-91%). Under both risk ratio reductions of 20% and 25%, 4/9 MAs were false negative and 1/9 false positive. The observed power based on the accrued sample size and observed risk ratio reduction was greater than 80% in 5/9 MAs. Conclusion: TSA detected one false positive MA of two trials comparing thalidomide with prednisone/dexamethosone for the outcome of overall survival. Future MAs need to consistently undertake TSA to avoid misleading conclusions. Disclosures: No relevant conflicts of interest to declare.

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