False Negative Values Research Articles

Meta-analysis of Diffusion-Weighted Magnetic Resonance Imaging to Predict Response to Chemoradiation Therapy in Patients With Head and Neck Squamous Cell Carcinoma

We performed a meta-analysis to evaluate the diagnostic performance of diffusion-weighted imaging (DWI) in predicting responses to chemoradiotherapy in patients with head and neck squamous cell carcinoma (HNSCC). A comprehensive literature search for reports of DWI in assessments of HNSCC response to chemoradiotherapy was conducted on the PubMed, EMBASE, and Cochrane library databases up to January 20, 2017. Eligible studies were reviewed for the following inclusion criteria: articles were reported in English; DWI was used for the evaluation of response to chemoradiotherapy of HNSCC; the raw data, including true positive, false positive, false negative, and true negative values, could be extracted or calculated; each study had at least 20 patients in the final analysis. The methodological quality of the included studies was assessed using QUADAS-2. Pooled sensitivity and specificity were calculated; the threshold effect and possible sources of heterogeneity were also analyzed. The summary receiver operating characteristic curve was constructed to calculate the area under the curve. Eleven studies comprising 515 patients were included in the meta-analysis. There was notable heterogeneity beyond threshold effect and publication bias. The pooled weighted sensitivity and specificity with corresponding 95% confidence intervals (CIs) were 79% (95% CI, 0.67-0.87) and 80% (95% CI, 0.73-0.86), respectively. The pooled diagnostic odds ratio was 12.34 (95%CI, 6.63–22.96). The area under the receiver operator characteristic curve was 0.84 (95% CI: 0.81, 0.87). The overall positive and negative likelihood ratios were 3.11 (95% CI, 2.24-4.15) and 0.33 (95% CI, 0.23-0.46), respectively. DWI is a relative accurate and non-invasive imaging technique for predicting response to chemoradiotherapy in HNSCC patients. Nevertheless, large-scale randomized controlled trials are warranted to validate the clinical value of DWI and to establish standards of measurement and analysis and cutoff values for response prediction.

Effectiveness of steganalysis based on machine learning methods

Subject of Study.The paper presents comparative accuracy estimation of modern machine learning-based steganalytic methods. The paper deals with the most perspective methods in tasks of the passive counteraction to the information transfer channels using the discrete wavelet domain of static digital images. Methods. We have studied methods proposed by Gireesh Kumar, Hany Farid, Changxin Liu, Yun Q. Shi and the SPAM method. Basically the methods apply statistical moments obtained from wavelet bands LL, HL, LH and HH, as well as additional image features forming a support vector. BOWS2 image collection was used to estimate the effectiveness of methods. Steganographic impact was modeled by changing the least significant bits of coefficients for the each DWT band (LL, LH, HL and HH) with 5% and 20% of payload. The effectiveness of explored methods is estimated in view of obtained true positive, true negative, false positive and false negative image classification values. Main Results. The study has shown that all explored methods except for SPAM are effective in the task of detecting of embedding in HH band. As for the detection of the embedding in LH band, Yun Q. Shi is the most effective algorithm. In the task of the detecting in HL band, all explored methods except for SPAM have appeared to be comparatively effective under condition of big payload. When detecting the embedding in LL band, all methods have shown the effectiveness about 50% regardless the payload rate. It is established that the considered methods are not able to render effective counteraction to the hidden data channel, using the LH and HL region due to the fact that they use Haar wavelet transform. It is concluded that the application of the optimal wavelet transform makes it possible to reduce the intersection area of value histograms of the first statistical moment for the original images and steganoimages. Practical Relevance. The work results are useful to the specialists in the field of information security in the tasks of detection and combating the hidden data channels. The obtained results can be used in the development of steganalysis systems and improved methods of steganalysis as well.

Accuracy of Middle Cerebral Artery Doppler Assessment between 34 and 37 Weeks in Fetuses with Red Cell Alloimmunization

Background: The Doppler measurement of middle cerebral artery peak systolic velocity (MCA-PSV) is considered the gold standard for the noninvasive detection of moderate to severe anemia. However, the accuracy of this test has not been evaluated so far, specifically beyond 34 weeks. Objectives: To assess the accuracy of MCA-PSV to detect moderate to severe fetal anemia and to identify risk factors associated with false-positive and false-negative MCA-PSV values after 34 weeks. Study Design: We studied a retrospective cohort of 150 pregnant women with severe alloimmunization who delivered between 2010 and 2014 and correlated MCA-PSV and fetal or neonatal hemoglobin levels. Results: Sensitivity to predict severe anemia was 69%, with a false-negative rate of 3.6%. When MCA Doppler assessment was normal, the identification of serosal effusions increased the detection rate of severe fetal anemia to 94%, with a false-negative rate of 0.8%. False-positive MCA-PSV measurements were more frequent in fetuses with 1 previous intrauterine transfusion (p = 0.0002), but were not associated with MCA resistance index, intrauterine growth restriction and fetal heart rate. Conclusions: Between 34 and 37 weeks, sensitivity of MCA-PSV Doppler assessment alone is 69% and increases to 94% when also considering signs of hydrops. False-positive MCA-PSV measurements are more frequent in case of former fetal transfusion.

Localized-atlas-based segmentation of breast MRI in a decision-making framework.

Breast-region segmentation is an important step for density estimation and Computer-Aided Diagnosis (CAD) systems in Magnetic Resonance Imaging (MRI). Detection of breast-chest wall boundary is often a difficult task due to similarity between gray-level values of fibroglandular tissue and pectoral muscle. This paper proposes a robust breast-region segmentation method which is applicable for both complex cases with fibroglandular tissue connected to the pectoral muscle, and simple cases with high contrast boundaries. We present a decision-making framework based on geometric features and support vector machine (SVM) to classify breasts in two main groups, complex and simple. For complex cases, breast segmentation is done using a combination of intensity-based and atlas-based techniques; however, only intensity-based operation is employed for simple cases. A novel atlas-based method, that is called localized-atlas, accomplishes the processes of atlas construction and registration based on the region of interest (ROI). Atlas-based segmentation is performed by relying on the chest wall template. Our approach is validated using a dataset of 210 cases. Based on similarity between automatic and manual segmentation results, the proposed method achieves Dice similarity coefficient, Jaccard coefficient, total overlap, false negative, and false positive values of 96.3, 92.9, 97.4, 2.61 and 4.77%, respectively. The localization error of the breast-chest wall boundary is 1.97mm, in terms of averaged deviation distance. The achieved results prove that the suggested framework performs the breast segmentation with negligible errors and efficient computational time for different breasts from the viewpoints of size, shape, and density pattern.

Breast-region segmentation in MRI using chest region atlas and SVM

An important step for computerized analysis of breast magnetic resonance imaging (MRI) is segmentation of the breast region. Due to the similar signal intensity of fibroglandular tissue and the chest wall, the segmentation process is difficult for breasts with fibroglandular tissue connected to the chest wall. In order to overcome this challenge, a new framework is presented that relies on a chest region atlas. The proposed method first detects the approximated breast-chest wall boundary using an intensity-based operation. A support vector machine (SVM) then determines the connectivity of fibroglandular tissue to the chest wall by the extracted features from the obtained breast-chest wall boundary. Finally, the obtained breast-chest wall boundary is accurately refined using the geometric shape of the chest region, which is obtained by an atlas-based segmentation method. The proposed method is validated using a dataset of 5964 breast MRI images from 126 women. The Dice similarity coefficient (DSC), total overlap (TO), false negative (FN), and false positive (FP) values are calculated to measure the similarity between automatic and manual segmentation results. Our method achieves DSC, TO, FN, and FP values of 96.46%, 96.41%, 3.59%, and 3.51%, respectively. The results prove the effectiveness of the presented algorithm for breasts with different sizes, shapes, and density patterns.

Spam filtering with sender authentication network

Unsolicited commercial and non-commercial e-mails occupy the Internet bandwidth redundantly, as well as the recipient's time and energy. In the fight against those spam e-mails, origin based spam filtering gained importance because of the low resource demands. Sender Policy Framework (SPF) protocol is one of the well-known origin based spam filtering techniques. In our study, Sender Authentication Network has been developed to extend the narrow utilization of the SPF technique. By analyzing the IP addresses in A and MX records, their relation with the IP address in SPF record is investigated. If the SPF record does not exist, a new one is created. After getting feedbacks from the volunteers for the false-positive and false-negative results, and applying a well-known spam filter to the contemporary dataset, we concluded that by low resource consumption, our method extracts spam e-mails faster than the present popular spam filtering methods. The results have acceptable false-positive and false-negative values.

Stress test of a biological early warning system with zebrafish (Danio rerio).

The aim of this work was to develop a novel methodology to stress test the diagnostic capability of a video tracking system with zebrafish (Danio rerio), against two pre-established disturbances. Eight different treatments were tested varying the presence or absence of a toxicant (NaOCl) and two disturbances: the passing of a shadow (mimicking a predator) and entrapment of the fish. The concentration tested corresponded to a sublethal (1 % 24 h-LC50) and short term exposure (2 h). A total of 56 organisms were tested resulting in 112 diagnoses (before and after the contamination). A statistical model of diagnosis was developed using Self-organizing Map (SOM) and Correspondence Analysis (CA). Sensitivity, specificity, accuracy, false positive and false negative values were calculated to evaluate the diagnostic performance. The disturbances did not negatively affect the capability of the model. In the presence of at least one of these variables, the diagnostic performance was similar or even superior to the baseline results without disturbances. Furthermore, the system produced a large number of correct diagnoses, at an ecologically relevant concentration of exposure, in a non-invasive way.

Value of Procalcitonin Measurement for Early Evidence of Severe Bacterial Infections in the Pediatric Intensive Care Unit

To determine whether peak blood procalcitonin (PCT) measured within 48 hours of pediatric intensive care unit (PICU) admission can differentiate severe bacterial infections from sterile inflammation and viral infection and identify potential subgroups of PICU patients for whom PCT may not have clinical utility. This was a retrospective, observational study of 646 critically ill children who had PCT measured within 48 hours of admission to an urban, academic PICU. Patients were stratified into 6 categories by infection status. We compared test characteristics for peak PCT, C-reactive protein (CRP), white blood cell count (WBC), absolute neutrophil count (ANC), and % immature neutrophils. The area under the receiver operating characteristic curve was determined for each biomarker to discriminate bacterial infection. The area under the receiver operating characteristic curve was similar for PCT (0.73, 95% CI 0.69, 0.77) and CRP (0.75, 95% CI 0.71, 0.79; P = .36), but both outperformed WBC, ANC, and % immature neutrophils (P < .01 for all pairwise comparisons). The combination of PCT and CRP was no better than either PCT or CRP alone. Diagnostic patterns prone to false-positive and false-negative PCT values were identified. Peak blood PCT measured close to PICU admission was not superior to CRP in differentiating severe bacterial infection from viral illness and sterile inflammation; both PCT and CRP outperformed WBC, ANC, and % immature neutrophils. PCT appeared especially prone to inaccuracies in detecting localized bacterial central nervous system infections or bacterial coinfection in acute viral illness causing respiratory failure.

Clinical and methodological factors affecting non-transferrin-bound iron values using a novel fluorescent bead assay

Nontransferrin-bound iron (NTBI) is a heterogeneously speciated plasma iron, typically detectable when transferrin saturation (TfSat) exceeds 75%. Here, we examine factors affecting NTBI levels by a recently discovered direct chelator-based (CP851) fluorescent bead-linked flow-cytometric assay (bead-NTBI), compared with the established indirect nitrilotriacetate (NTA) assay in 122 iron-overloaded patients, including 64 on recent iron chelation therapy and 13 healthy volunteers. Both methods correlated (r = 0.57, P < 0.0001) but with low agreement, attributable to 2 major factors: (1) the NTA method, unlike the bead method, is highly dependent on TfSat, with NTBI under-estimation at low TfSat and over-estimation once Tf is saturated, (2) the bead method detects <3-fold higher values than the NTA assay in patients on recent deferiprone-containing chelation due to greater detection of chelate complexes but lower values for patients on deferasirox. The optimal timing of sample collection relative to chelation dosing requires further study. Patients with splenectomy, high-storage iron, and increased erythropoiesis had greater discrepancy between assays, consistent with differential access by both methods to the NTBI pools associated with these clinical variables. The bead-NTBI assay has advantages over the NTA assay, being less dependent on TfSat, hence of less tendency for false-negative or false-positive values at low and high TfSat, respectively.

SU‐F‐T‐235: Optical Scan Based Collision Avoidance Using Multiple Stereotactic Cameras During Simulation

Purpose:To demonstrate the ability to quickly generate an accurate collision avoidance map using multiple stereotactic cameras during simulation.Methods:Three Kinect stereotactic cameras were placed in the CT simulation room and optically calibrated to the DICOM isocenter. Immediately before scanning, the patient was optically imaged to generate a 3D polygon mesh, which was used to calculate the collision avoidance area using our previously developed framework. The mesh was visually compared to the CT scan body contour to ensure accurate coordinate alignment. To test the accuracy of the collision calculation, the patient and machine were physically maneuvered in the treatment room to calculated collision boundaries.Results:The optical scan and collision calculation took 38.0 seconds and 2.5 seconds to complete respectively. The collision prediction accuracy was determined using a receiver operating curve (ROC) analysis, where the true positive, true negative, false positive and false negative values were 837, 821, 43, and 79 points respectively. The ROC accuracy was 93.1% over the sampled collision space.Conclusion:We have demonstrated a framework which is fast and accurate for predicting collision avoidance for treatment which can be determined during the normal simulation process. Because of the speed, the system could be used to add a layer of safety with a negligible impact on the normal patient simulation experience. This information could be used during treatment planning to explore the feasible geometries when optimizing plans.Research supported by Varian Medical Systems

Dilute Russell's viper venom and activated partial thromboplastin time in lupus anticoagulant diagnosis: is mixing essential?

Dilute Russell's viper venom (DRVV) testing and activated partial thromboplastin time (APTT) have been effectively used in combination for lupus anticoagulant testing. The purpose of our study was to evaluate the role of mixing in activated partial thromboplastin and dilute Russell's viper venom testing for evaluation of lupus anticoagulants. Citrated blood from patients who were not on oral anticoagulant therapy was studied. Mixing study with 1 : 1 normal plasma for elevated APTT and also few samples with elevated screen time was carried out. Elevated APTT was seen in only 48.1% of patients with lupus anticoagulant. Correction of APTT was seen in 27.8% of lupus anticoagulant-positive patients. DRVV test on mixing resulted in 83.8% false-negative values. Integrated DRVV test could be a standalone test for testing lupus anticoagulant. Mixing study may be restricted for patients on oral anticoagulants or patients with strong lupus anticoagulant.

The C-Reactive Protein May Not Detect Infections Caused by Less-Virulent Organisms

BackgroundThe aim of the present study was to evaluate the influence of organism type on the performance of the synovial fluid C-reactive protein (CRP) test. MethodsWe retrospectively reviewed the results of 21,422 synovial fluid samples sent to one common laboratory for the purpose of diagnostic testing for periprosthetic joint infection. Both a synovial fluid CRP result and a positive culture were present for 1789 submitted samples. The cultured organisms were grouped by species, virulence, and gram type; and the median CRP level was determined for each group. ResultsThe median synovial fluid CRP level was significantly lower for less-virulent organisms, when compared to those organisms classified as virulent (15.10 mg/L vs 32.70 mg/L; P < .0001). Some less-virulent species such as yeast and Staphylococcus epidermidis were associated with a 4-10 times lower CRP response than those of virulent organisms such as Streptococcus agalactiae and Staphylococcus aureus (P < .0001). Bacterial gram type had no influence on the median CRP result. The rate of false-negative CRP values was 50.9% for yeast, 29.4% for S. epidermidis, 28.5% for all less-virulent organisms, and 11.6% for all virulent organisms. ConclusionThe CRP response appears to be highly dependent on the infecting organism and is more likely to provide false-negative results in the setting of less-virulent organisms. Although the use of a CRP level is an important part of the workup for periprosthetic joint infection, surgeons must be aware that this protein may yield a false-negative result in the setting of less-virulent organisms.

Comparison of Snellen and Early Treatment Diabetic Retinopathy Study charts using a computer simulation.

To compare accuracy, reproducibility and test duration for the Snellen and the Early Treatment Diabetic Retinopathy Study (ETDRS) charts, two main tools used to measure visual acuity (VA). A computer simulation was programmed to run multiple virtual patients, each with a unique set of assigned parameters, including VA, false-positive and false-negative error values. For each virtual patient, assigned VA was randomly chosen along a continuous scale spanning the range between 1.0 to 0.0 logMAR units (equivalent to 20/200 to 20/20). Each of 30 000 virtual patients were run ten times on each of the two VA charts. Average test duration (expressed as the total number of characters presented during the test ±SD) was 12.6±11.1 and 31.2±14.7 characters, for the Snellen and ETDRS, respectively. Accuracy, defined as the absolute difference (± SD) between the assigned VA and the measured VA, expressed in logMAR units, was superior in the ETDRS charts: 0.12±0.14 and 0.08±0.08, for the Snellen and ETDRS charts, respectively. Reproducibility, expressed as test-retest variability, was superior in the ETDRS charts: 0.23±0.17 and 0.11±0.09 logMAR units, for the Snellen and ETDRS charts, respectively. A comparison of true (assigned) VA to measured VA, demonstrated, on average, better accuracy and reproducibility of the ETDRS chart, but at the penalty of significantly longer test duration. These differences were most pronounced in the low VA range. The reproducibility using a simulation approach is in line with reproducibility values found in several clinical studies.

Diffusion-weighted MRI in differentiating malignant from benign thyroid nodules: a meta-analysis

ObjectivesTo perform a meta-analysis to evaluate the diagnostic efficacy of diffusion-weighted imaging (DWI) in differentiating malignant from benign thyroid nodules.DesignA meta-analysis.Data sources and study selectionMedical and scientific literature databases were...

Hygiene-therapists could be used to screen for dental caries and periodontal disease.

A purposive sample of large NHS dental practices with a minimum of three surgeries employing at least one hygiene-therapist (HT) was taken. Asymptomatic patients attending for routine checkups who consented to the study underwent a screen by H-T for dental caries and periodontal disease (index test) followed by a screen by a general dental practitioner (reference test). Patients were recruited consecutively. H-Ts and dentists attended a compulsory training day, which covered recruitment, consenting, screening process, calibration using stock photographs and patient record form completion. Diagnostic threshold for caries was any tooth in the patient's mouth that showed evidence of frank cavitation or shadowing and opacity that would indicate dental caries into the dentine. The diagnostic threshold for periodontal disease was any pocket in the patient's mouth where the black-band of a basic periodontal examination (BPE) probe (3.5 to 5.5 mm) partially or totally disappeared (ie BPE code 3). The index test was compared with the reference test to determine true-positive, false-positive, false-negative and true-negative values. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic odds ratios are shown in Table 1. Eighteen hundred and ninety-nine patients consented to dental screening with 996 patients being randomly allocated to see the dentist first and 903 H-T first. The time interval between the index and reference test never exceeded 21 minutes. With the exception of two practices failing to collect data on smoking and dentures there were no missing results regarding the outcome of a positive or negative screening decision. No adverse events were reported. Mean screening time was five min 25 s for H-Ts and four min 26 s for dentists. Dentists identified 668 patients with caries (Prevalence of 0.35) while H-Ts classified 548 positive and correctly identified 1,047 of the 1,231 patients with no caries. Dentists identified 1074 patients with at least one pocket exceeding 3.5 mm in depth. Of these 935 were correctly identified by the H-Ts. For the 825 screened as negative by the dentist H-Ts correctly identified 621. The results suggest that hygiene-therapists could be used to screen for dental caries and periodontal disease. This has important ramifications for service design in public-funded health systems.

Heart Sound Localization in Respiratory Sound Based on a New Computationally Efficient Entropy Bound.

A new entropy bound with low computational complexity for differential Shannon entropy estimation with kernel density approach is proposed in this study, which is based on defining a bound for the Kullback-Leibler divergence between two Gaussian mixture models. The proposed entropy bound is derived to provide computational efficiency without decreasing the accuracy in detecting heart sound segments in respiratory sound. It is shown both theoretically and experimentally that using the proposed bound in an adaptive threshold-based detection method gives very similar performance compared to that obtained by a nonparametric kernel based approach, while its computational cost is much lower. The performance of the proposed method is shown and compared with the three methods in the literature by means of experiments utilizing a database of 20 subjects. The results show that the false negative rate values for the proposed method are 1.45±1.50 % and 1.98±1.81 % for low and medium flow rates, respectively. These average values are similar to the results obtained by the alternative methods. Moreover, the average elapsed time of the proposed method for a piece of data with a length of 20 s is 0.05 s, which is significantly lower than that of the other methods.

Accuracy of Combined Visual Inspection with Acetic Acid and Cervical Cytology Testing as a Primary Screening Tool for Cervical Cancer: a Systematic Review and Meta-Analysis.

The performance of combined testing visual inspection with acetic acid (VIA) and cervical cytology tests might differ from one setting to another. The average estimate of the testing accuracy across studies is informative, but no meta-analysis has been carried out to assess this combined method. The objective of this study was to estimate the average sensitivity and specificity of the combined VIA and cervical cytology tests for the detection of cervical precancerous lesions. We conducted a systematic review and a meta-analysis, according to the Cochrane Handbook for Systematic Review of Diagnostic Test Accuracy. We considered two cases. In the either-positive result case, a positive result implies positivity in at least one of the tests. A negative result implies negativity in both tests. In the both-positive case, a positive result implies having both tests positive. Eligible studies were identified using Pubmed, Embase, Website of Science, CINHAL and COCRANE databases. True positive, false positive, false negative and true negative values were extracted. Estimates of sensitivity and specificity, positive and negative likelihood (LR) and diagnostic odds ratios (DOR) were pooled using a hierarchical random effect model. Hierarchical summary receiver operating characteristics (HSROC) were generated and heterogeneity was verified through covariates potentially influencing the diagnostic odds ratio. Nine studies fulfilled inclusion criteria and were included in the analysis. Pooled estimates of the sensitivities of the combined tests in either-positive and both-positive cases were 0.87 (95% CI: 0.83-0.90) and 0.38 (95% CI: 0.29-0.48), respectively. Corresponding specificities were 0.79 (95% CI: 0.63-0.89) and 0.98 (95% CI: 0.96-0.99) respectively. The DORs of the combined tests in either-positive or both-positive result cases were 27.7 (95% CI: 12.5-61.5) and 52 (95% CI: 22.1-122.2), respectively. When including only articles without partial verification bias and also a high-grade cervical intraepithelial neoplasia as a threshold of the disease, DOR of combined test in both-positive result cases remained the highest. However, DORs decreased to 12.1 (95% CI: 6.05-24.1) and 13.8 (95% CI: 7.92-23.9) in studies without partial verification bias for the combined tests in the either-positive and both-positive result cases, respectively. The screener, the place of study and the size of the population significantly influenced the DOR of combined tests in the both-positive result case in restriction analyses that considered only articles with CIN2+ as disease threshold. The combined test in the either-positive result case has a high sensitivity, but a low specificity. These results suggest that the combined test should be considered in developing countries as a primary screening test if facilities exist to confirm, through colposcopy and biopsy, a positive result.

Are emergency physicians competent to interpret the cranial CT of patients younger than the age of 2 years with mild head trauma?

ObjectiveThe aim of this study is to detect the accuracy rate of emergency physicians' (EPs') interpretations of cranial computed tomography (CT) of a special patient group, the patients younger than the age of 2 years with mild head trauma. MethodsThe study took place in a research and training hospital within a period of 3 months and included a total of 156 patients. The scans were interpreted by the EPs, and the predicted results were recorded in the patients' files; simultaneous interpretations of the on-call radiologist were also recorded. The interpretations were scanned retrospectively at the end of each month, compared, and recorded. ResultsWith reference to the radiologists' reports, the sensitivity and the specificity of EPs' interpretations of cranial CT were 76.9% and 95.1%, respectively. Concordance of both groups' interpretations was 93.6%. The area under the curve (AUC) value in receiver operating characteristic (ROC) analysis, which reflects these results, was calculated as 0.860 (95% confidence interval, 0.740-0.981). This value was found to be statistically significant (P < .001). False-negative and false-positive values were 23% and 4.9%, respectively. No negative clinical outcomes were observed due to nonconcordance interpreted cases (6.4%). ConclusionsEmergency physicians can interpret safely the cranial CTs of patients younger than the age of 2 years with mild head trauma, until the radiologists' reports are obtained. However, the anatomic diversities of these patients' age group should be taken into consideration.

Continence Index: a new screening questionnaire to predict the probability of future incontinence in older women in the community.

Urinary incontinence (UI) is a chronic, costly condition that impairs quality of life. To identify older women most at risk, the Medical Epidemiologic and Social Aspects of Aging (MESA) datasets were mined to create a set of questions that can reliably predict future UI. MESA data were collected during four household interviews at approximately 1 year intervals. Factors associated with becoming incontinent at the second interview (HH2) were identified using logistic regression (construction datasets). Based on p values and odds ratios, eight potential predictive factors with their 256 combinations and corresponding prediction probabilities formed the Continence Index. Its predictive and discriminatory capability was tested against the same cohort's outcome in the fourth survey (HH4 validation datasets). Sensitivity analysis, area under receiver operating characteristic (ROC) curve, predicted probabilities and confidence intervals were used to statistically validate the Continence Index. Body mass index, sneezing, post-partum UI, urinary frequency, mild UI, belief of developing UI in the future, difficulty stopping urinary stream and remembering names emerged as the strongest predictors of UI. The confidence intervals for prediction probabilities strongly agreed between construction and validation datasets. Calculated sensitivity, specificity, false-positive and false-negative values revealed that the areas under the ROCs (0.802 and 0.799) for the construction and validation datasets, respectively, indicated good discriminatory capabilities of the index as a predictor. The Continence Index will help identify older women most at risk of UI in order to apply targeted prevention strategies in women that are most likely to benefit.

Contrast-enhanced MRI in preoperative assessment of myometrial and cervical invasion, and lymph node metastasis: diagnostic value and error analysis in endometrial carcinoma.

To determine the ability of contrast-enhanced magnetic resonance imaging to predict myometrial invasion, cervical invasion, and pelvic lymph node metastasis in endometrial carcinoma and to analyze factors that lead to errors in this identification. A retrospective study. University general hospital. A total of 167 women diagnosed with endometrial carcinoma. All patients received a preoperative contrast-enhanced magnetic resonance imaging scan. Histopathological findings were used as the definitive diagnosis. The results were compared with histopathological findings, factors that make accurate assessment of myometrial invasion, cervical invasion, and pelvic lymph node metastasis difficult by contrast-enhanced magnetic resonance imaging were analyzed. The sensitivity, specificity, diagnostic accuracy, positive predictive values, and negative predictive values of contrast-enhanced magnetic resonance imaging were 90.9, 91.8, 91.6, 73.2 and 97.6%, respectively, for identifying deep myometrial invasion; 84.2, 96.0, 94.6, 72.7 and 97.9%, respectively, for identifying cervical invasion; and 45.0, 91.2, 85.6, 40.9 and 92.4%, respectively, for identifying pelvic lymph node metastasis. The main causes of error in contrast-enhanced magnetic resonance imaging were myomas, cornual lesions, deep myometrial invasion, large tumor size, non-endometrioid tumor type, and lower tumor grade. Contrast-enhanced magnetic resonance imaging has a high accuracy and a low tendency to produce false-negative predictive values. Gynecological oncologists should combine the imaging data and clinical information to make therapeutic decisions and avoid diagnostic errors.