negative predictive value(NPV)

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RULING OUT PE: A NOVEL APPROACH USING END-TIDAL CO2 WITH COMPRESSION ULTRASONOGRAPHY AND TRANSTHORACIC ECHOCARDIOGRAPHY IN PULMONARY EMBOLISM DIAGNOSIS (CUEPED)

RULING OUT PE: A NOVEL APPROACH USING END-TIDAL CO2 WITH COMPRESSION ULTRASONOGRAPHY AND TRANSTHORACIC ECHOCARDIOGRAPHY IN PULMONARY EMBOLISM DIAGNOSIS (CUEPED)

All statistical analyses were done using SPSS 21.0. For demographic characterist ic and clinical profile data, categorical data are presented as percentage and numerical data are presented as mean (SD). Diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of CUEPED were calculated with 95% confidence interval.

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Magnetic Resonance Arthrography, a valuable pre-operative imaging modality in femoro-acetabular impingement

Magnetic Resonance Arthrography, a valuable pre-operative imaging modality in femoro-acetabular impingement

Data was analyzed using SPSS win statistical package version 21 (SPSS Inc., Chicago, IL). Numerical data were expressed as mean, and standard deviation or median and range as appropriate. Qualitative data were expressed as frequency and percentage. Chi- square test (Fisher’s exact test) was used to examine the relation between qualitative variables. For quan- titative data, a comparison between two groups was done using either student t test or Mann-Whitney test (non-parametric t test) as appropriate. A P value of less than 0.05 was considered significant. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MR arthrography for diagnosing the acetabular labral tears and chondral abnormalities were calculated, using the results of hip arthroscopy as the gold standard.
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Association between Hoehn and Yahr, Mini-Mental State Examination, age, and clinical syndrome predominance and diagnostic effectiveness of ioflupane I 123 injection (DaTSCANTM) in subjects with clinically uncertain parkinsonian syndromes

Association between Hoehn and Yahr, Mini-Mental State Examination, age, and clinical syndrome predominance and diagnostic effectiveness of ioflupane I 123 injection (DaTSCANTM) in subjects with clinically uncertain parkinsonian syndromes

report the diagnostic effectiveness (sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy) of ioflupane [ 123 I] imaging versus the final clinical diagnosis for subjects who had both ioflu- pane [ 123 I] imaging results at baseline and a specific clin- ical diagnosis 1 year post scan, including analyses based on subject’s Hoehn and Yahr (H&Y) stage, Mini-Mental State Examination (MMSE) score, age, and predominant clinical syndrome subgroup. It has already been estab- lished that age is a contributing factor in the progressive decline of dopamine transporter (DaT) binding in healthy aging subjects [2]. However, it has also been shown that age of Parkinson’ s disease (PD) patients contributes to dis- ease severity, independent of the duration of disease [3].
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Identifying diabetes cases from administrative data: a population based validation study

Identifying diabetes cases from administrative data: a population based validation study

One way to address this issue is to limit case definitions for diabetes to those with high PPV. Generally a PPV of 70% or greater has been considered optimal for disease algorithms using administrative or claims data [20]. However an even higher PPV (e.g. > 80%), combined with high specificity (> 98%) may be preferable in large study samples to minimize the inclusion of false positive cases [19]. One rule may thus not be sufficient for all purposes, populations, and database settings. First, the need to prioritize specificity and PPV (to identify a diabetes cohort) versus sensitivity and negative predictive value, NPV (to exclude persons with pre-existing diabetes) may vary for different research objectives and purposes. Second, PPV is highly dependent on the prevalence of disease in a particu- lar population necessitating unique algorithms based on underlying prevalence (e.g. young versus older) [20]. Third, algorithms need to be flexible to account for variations in data availability across settings (e.g. medication data, special fee codes).
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Evaluation of IL-6, CRP and hs-CRP as Early Markers of Neonatal Sepsis

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Statistical analysis was done by using SPSS software version 21. Mean and Standard Deviation (SD) was calculated to assess the level of CRP and IL-6. The difference in the level of IL-6 and CRP among the case groups and control groups were assessed using student t-test. The difference between the two groups was considered to be statistically significant, when the p-value was less than 0.05, while performing student t-test. The sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV) for all the parameters were calculated. Receiver Operating Characteristics (ROC) curve was drawn to determine the sensitivity, specificity for all the parameters and Area Under the Curve (AUC) was compared.
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A study of Revised National Tuberculosis Control Programme quality assurance of sputum microscopy at tuberculosis unit

A study of Revised National Tuberculosis Control Programme quality assurance of sputum microscopy at tuberculosis unit

Data processing and statistical analysis were performed using the Graph Pad Instat and MedCalc softwares (Windows version 3.10 and 12.75 respectively). The percentages of different types of errors were calculated for each DMC. The sensitivity, specificity, Positive predictive value (PPV), Negative predictive value (NPV) of smear reading by was calculated. Chi square test was used to see any association with different variable. The agreement in reading between the SM and STLS was done using kappa statistics and p value less than 0.05 was considered to be statistically significant.
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Early Diagnosis of Extrapulmonary Tuberculosis by a New Procedure Combining Broth Culture and PCR

Early Diagnosis of Extrapulmonary Tuberculosis by a New Procedure Combining Broth Culture and PCR

there is no clear recommendation for the use of NAATs in the setting of ETB. Three recent meta-analyses synthesizing the results of nearly 140 studies have examined the current evi- dence on the performance of these tests for the diagnosis of TB lymphadenitis, pleuritis, and meningitis (3, 13, 14). According to these studies, NAATs have high specificity and positive predictive value but low and variable sensitivity and negative predictive value in all forms of ETB. Whereas a positive result strongly suggests TB, a negative result does not exclude TB with certainty. Thus, the current evidence suggests that NAATs cannot replace conventional tests such as microscopy and culture and that they should be interpreted in conjunction with these tests and clinical data (15, 17). In clinical practice, the results of NAATs do not weigh significantly on decision making in sus- pected ETB, and antituberculous treatment given presumptively is rarely discontinued until final culture results are available (21). Further work is therefore needed to develop new methods with enhanced sensitivity while maintaining high specificity.
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PRACTICE PARAMETER: THE USEFULNESS OF EVOKED POTENTIALS IN IDENTIFYING CLINICALLY SILENT LESIONS IN PATIENTS WITH SUSPECTED MULTIPLE SCLEROSIS (AN EVIDENCE-BASED REVIEW)

PRACTICE PARAMETER: THE USEFULNESS OF EVOKED POTENTIALS IN IDENTIFYING CLINICALLY SILENT LESIONS IN PATIENTS WITH SUSPECTED MULTIPLE SCLEROSIS (AN EVIDENCE-BASED REVIEW)

For each EP technique studied we calculated the following parameters: sensitivity—the proportion of MS suspects developing CDMS with abnormal EPs; specificity—the proportion of MS suspects not developing CDMS with normal EPs. We also calculated the positive predictive value (PPV)—the proportion of MS suspects with abnormal EPs developing CDMS; and the complement of the negative predictive value (NPVc)—the proportion of MS suspects with normal EPs developing CDMS. Additionally, we determined the relative rate that patients with abnormal EPs developed CDMS as compared to patients with normal EPs by dividing the PPV by the NPVc. As an overall measure of the strength of the association between EP results and eventual CDMS, we calculated Goodman and Kruskal’s tau. 11 (In the current
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The Accuracy of Kidney Injury Molecule- 1 for Earlier Diagnosis Acute Kidney Injury in Polytrauma

The Accuracy of Kidney Injury Molecule- 1 for Earlier Diagnosis Acute Kidney Injury in Polytrauma

The examination of KIM-1 concentration in polytrauma patients has a good AUC value, accuracy, sensitivity, specificity, positive predictive value, and negative predictive value. The results of the study are in accordance with a comparison of plasma KIM-1 levels in post-cardiac surgery patients, in that KIM-1 levels were higher in adult patients with AKI compared to healthy controls or post-cardiac surgery patients without AKI with an AUC value of 0.96. [7, 18] Another study said that KIM-1 levels significantly increased 12 hours after operation in pediatric patients with AKI who underwent cardiac surgery with an AUC value of 0.86. [6, 18] In this study all the results are quite well, but conducted only in a single centre and not to many sample size adopted. I suggest in the future other study will be conducted in multi centre and bigger sample size adopted. The disadvantage of KIM-1 measurenment hasn’t been applied in daily clinical practice limited in the laboratory.
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Comparative Study between Intraoperative Frozen Section and Scrape Smear Cytology in the Diagnosis of Ovarian Neoplasm

Comparative Study between Intraoperative Frozen Section and Scrape Smear Cytology in the Diagnosis of Ovarian Neoplasm

ovarian masses were 100%, 95.9%, 33.3%, 100% and 96% respectively. The sensitivity, specifici- ty, positive predictive value, negative predictive value and accuracy of frozen section in the diag- nosis of malignant ovarian masses were 90%, 100%, 100%, 93.8% and 96% respectively. Conclu- sion: Frozen section is more accurate than smear preparations in the intraoperative assessment of ovarian tumors in this study. However, the cytology preparations were helpful in supporting the histological diagnoses, and in some cases, provided additional useful information. Thus, cytology has a complementary role to frozen section in the intraoperative assessment of ovarian lesions. At the centers where the facilities of frozen section are not available, intraoperative scrape cytology is a useful tool for intraoperative diagnosis of tumor.
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Focused Sonography in Detecting Hemoperitoneum in Blunt Abdominal Trauma Patients, Correlation with Computed Tomography

Focused Sonography in Detecting Hemoperitoneum in Blunt Abdominal Trauma Patients, Correlation with Computed Tomography

All collected information was entered into SPSS version 10 and analyzed through it. Male to female ratio and mean standard deviation for age distribution were computed. Graphs and charts regarding gender, mechanism of trauma and time lapse between trauma and Focused assessment with sonography for trauma were obtained. A 2x2 table was constructed and sensitivity, specificity, positive predictive value, negative predictive value and accuracy of Focused assessment with sonography for trauma in detecting hemoperitoneum in blunt abdominal trauma were calculated by using computed tomography findings.
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Mature Glycoprotein G Presents High Performance in Diagnosing Herpes Simplex Virus Type 2 Infection in Sera of Different Tanzanian Cohorts

Mature Glycoprotein G Presents High Performance in Diagnosing Herpes Simplex Virus Type 2 Infection in Sera of Different Tanzanian Cohorts

Herpes simplex virus type 2 (HSV-2) is a common sexually transmitted infection in sub-Saharan Africa. Glycoprotein G (gG) of HSV-2 elicits a type-specific antibody response and is widely used for serodiagnosis. gG is cleaved into a secreted portion (sgG-2) and a highly O-glycosylated mature portion (mgG-2). The perfor- mances of these two native immunosorbent purified antigens were compared in an enzyme-linked immunosor- bent assay (ELISA) format with a commercially available assay (FOCUS2) using sera from blood donors (n ⴝ 194) and individuals (n ⴝ 198) with genital ulcer disease (GUD) from Tanzania. Discordant results were resolved by Western blotting. The HSV-2 seroprevalence for blood donors was estimated as 42%, and that for the GUD cohort was estimated as 78%. The prevalence increased significantly with age for both cohorts and was higher among human immunodeficiency virus (HIV)-positive individuals than among HIV-negative sub- jects. In the GUD cohort with a high HSV-2 prevalence, all three assays showed statistically similar perfor- mances, with sensitivities between 97% and 99% and specificities in the range of 86% to 91%. In contrast, among blood donors with a lower seroprevalence, the mgG-2-based ELISA presented significantly higher specificity (97%) than the sgG-2 ELISA (89%) and FOCUS2 (74%). Overall, the mgG-2 ELISA gave a high performance, with negative and positive predictive values of 96% for blood donors and a negative predictive value of 95% and a positive predictive value of 97% for the GUD cohort. We conclude that native purified mgG-2 showed the highest accuracy for detection of HSV-2 in patient sera from Tanzania and is therefore suitable for seroprevalence studies as well as in clinical settings.
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Clinical features and septic screen in neonatal sepsis in a teaching hospital in India

Clinical features and septic screen in neonatal sepsis in a teaching hospital in India

Methods: A one-year descriptive cross-sectional study was carried out at the NICU of a teaching hospital in India. Results: The incidence of clinically suspected septicemia was 19.3 per 1000 live births and the incidence of blood culture positive septicemia was 2.9 per 1000 live births among the inborn of the hospital. The most common clinical features were poor suck and lethargy in culture positive sepsis. The most common organisms causing sepsis were Coagulase negative staphylococci and Klebsiella. In the septic screen CRP was found to have a statistically significant association with blood culture positive sepsis. CRP also had the highest sensitivity and negative predictive value among the studied parameters.
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The error rate are 40%, 9.52%, 17.65% and 7.14% consecutively to diagnose stage IA1, IB1, IB2 and IIA. Sensitivity, specificity, positive predictive value and negative predictive value for lymph nodes exami- nation are 11.11%, 100%, 100% and 85.96%. Sensi- tivity, specificity, positive predictive value and nega- tive predictive value for parametrial involvement are 37.5%, 100%, 100% and 90.90%. Sensitivity, speci- ficity, positive predictive value and negative predic- tive value for cervical length examination are 91.84%, 88.89%, 97.83% and 66.67%. Supportive examina- tions would help clinician to obtain an optimal result of staging.
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Significance of results in cancer imaging

Significance of results in cancer imaging

Diagnostic performance is concerned with the ability of the technique to identify disease correctly. Thus, diagnostic performance is a measure of sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the technique in a given clinical situation. This is a familiar method of evaluating imag- ing in cancer and the major method by which different imaging techniques are compared. Thus, the decision to use one imaging technique for staging cancer in prefer- ence to another is frequently based on information provided on diagnostic performance. While it is not possible to discuss the use of statistics in detail, it is important to recognize that studies should be designed to answer an hypothesis and that the help of a statisti- cian to design a study is likely to yield enormous benefits by reducing inappropriate methodology and bias [1] .
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Evaluation of portable colposcopy and human papillomavirus testing for screening of cervical cancer in rural China

Evaluation of portable colposcopy and human papillomavirus testing for screening of cervical cancer in rural China

Conclusion While HPV testing has high sensitivity and specificity for the detection of pre-cancerous and cancerous lesions and portable colposcopy has lower specificity, both methods of detection have low positive predictive value and high negative predictive value. In tandem, HPV testing and portable colposcopy had higher sensitivity for detection among women who underwent biopsies. In clinical practice, portable colposcopy was an effective, easy and affordable tool to transport to villages where cytology is not currently feasible.

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Sensitivity, specificity and predictive values of anterior chamber tap in cases of bacterial endophthalmitis

Sensitivity, specificity and predictive values of anterior chamber tap in cases of bacterial endophthalmitis

Methods: Retrospective, single centre, case series study. We reviewed all medical records with clinical diagnosis of bacterial endophthalmitis in our hospital from January 1st, 2000 to December 31st 2014. From each record, we documented general demographic data, best corrected visual acuity and vitreous and aqueous tap microbiological results. All cases were further divided according to the endophthalmitis aetiology to perform individual calculations of sensitivity, specificity, positive predictive value, negative predictive value, accuracy and prevalence. We used the results of the vitreous tap as the gold standard for diagnosis of bacterial endophthalmitis. We excluded those records in which the aqueous and vitreous samples were not taken simultaneously or had an incomplete microbiological report. Significance were assessed with chi squared statistics, with an alpha value of 0.05 for statistical significance.
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Accuracy of Intraoperative Frozen Section in the Diagnosis of Ovarian Neoplasms

Accuracy of Intraoperative Frozen Section in the Diagnosis of Ovarian Neoplasms

Objective: The aim of the work is to evaluate the accuracy of intraoperative frozen section in the diagnosis of ovarian neoplasms in Zagazig University. Design: A prospective cross sectional cohort study. Method: This study was performed between March 2011 and March 2012, on 50 patients presented with ovarian mass. Gross examination of the tumor removed was done by inspection and palpation. The specimen was then cut with a sharp knife into two halves. The most appropri- ate area thought to be representative of lesion was chosen. The number of sections frozen was depended on the type and size of the tumor. Seven to eight μm sections were obtained and stained with hematoxylin-eosin. The specimens were then fixed in formalin. Paraffin blocks of the sections were processed in the routine way and sections were stained with hematoxylin and eosin (H and E). The diagnosis obtained by intraoperative frozen section based on cellularity and cell mor- phology was compared with final histopathological diagnosis in terms of diagnostic sensitivity, to differentiate between benign and malignant lesions. Assessment of the overall accuracy of the intraoperative diagnosis was classified as concordant or discordant. Results: There was no statis- ticaly significant differencre in the studied patients as regard the clinical data, macroscopic and intraoperative picture, while there was statisticaly significat association as regard the laterality of the ovarian masses. The validity of frozen section in the diagnosis of benign tumour was 100% with 100% accuracy, specificity, positive predictive value, negative predictive value, while sensi- tivity & negative prediction for borderline tumour and specificity & positive prediction of malig- nant tumour were 100%, specifecity for borderline tumours was 95% while the positive predic- tive value was 33.3% with 96% accuracy for both malignant and borderline tumours. Conclusion: Intraoperative frozen section is accurate for rapid diagnosis of ovarian tumors. It can help surge- ons avoid under-treatment or overtreatment of patients. Our study was designed prospectively
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The usefulness of MR in establishing the diagnosis of parotid pleomorphic adenoma

The usefulness of MR in establishing the diagnosis of parotid pleomorphic adenoma

PURPOSE: To assess the usefulness of MR findings in establishing a specific diagnosis of parotid pleomorphic adenoma. METHODS: T1-weighted and T2-weighted MR images with and without contrast enhancement were obtained in 82 patients with parotid tumors. Imaging findings in the 38 patients in whom surgery subsequently revealed pleomorphic adenomas were compared with findings in the 44 patients who had other types of tumor. Specifically, the homogeneity, signal intensity, contrast enhancement, capsule thickness, lobulation, adenopathy, and infiltration of adjacent fat were compared among the different types of tumor. The sensitivity, specificity, positive predictive value, and negative predictive value were calculated. RESULTS: A low-signal capsule on T2-weighted images and a lobulated contour characterized most pleomorphic adenomas. The sensitivity of the first finding for pleomorphic adenoma was 82%; specificity, 85%; positive predic- tive value, 82%; and negative predictive value, 84%. For the second finding, the sensitivity was 53%; specificity, 84%; positive predictive value, 74%; and negative predictive value, 67%. CON- CLUSION: None of the signs evaluated had perfect sensitivity and specificity. The MR findings of a complete capsule, lobulated contour, or high T2 signal intensity have a high predictive value for the diagnosis of pleomorphic adenoma.
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Diagnosing Cerebral Venous Sinus Thrombosis on Unenhanced Computed Tomography -Measuring the Hounsfield Unit. Does it Add to the Confirmation of Diagnosis?

Diagnosing Cerebral Venous Sinus Thrombosis on Unenhanced Computed Tomography -Measuring the Hounsfield Unit. Does it Add to the Confirmation of Diagnosis?

Methods: Institutional ethical review committee approval was obtained prior to start of this retrospective study. All Magnetic resonance venogram (MRV) performed between January 2007 and December, 2016 were reviewed retrospectively. Only positive cases were included which show thrombosis on MRV. We calculated sensitivity, specificity, positive predictive value and negative predictive value on the basis of CT density taking post contrast MRV as gold standard.

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