False-positive Group Research Articles

Risk factors associated with the false positive of cardiopulmonary exercise test in the diagnosis of coronary heart disease

PurposeCardiopulmonary exercise test (CPET) is a common method for preliminary evaluating coronary heart disease (CHD), but it may experience false positive. The present study aimed to reveal the potential factors relating to the false positive of CPET, including blood glucose and lipids.MethodsThis observational cohort study included 103 subjects with false positive of CPET and 65 subjects with true positive of CPET. The baseline characteristics, blood glucose, and blood lipids between the true and false positive groups were compared. After adjusting for the age and sex, logistic regression analysis was performed to reveal the potential risk factors of false positive. Receiver operating characteristic curve analysis was performed to evaluate the potential of related factors in distinguishing between true and false positive results.ResultsMales, smokers, and patients with diabetes were less likely to suffer from false positive of CPET. Compared with the true positive group, the false positive group exhibited significantly higher levels of high-density lipoprotein (HDL) and apolipoprotein A1 (Apo-A1), and lower levels of fasting blood glucose (FBG) and glycosylated hemoglobin (GHb). After adjustment, FBG and GHb were protective factors of the true positive of CPET, and they both had moderate ability to distinguish false positive from true positive in females. However, their combination did not improve the discriminative effect more obviously than FBG alone.ConclusionsSex, smoking, diabetes, and blood glucose were associated with the false positive of CPET. FBG was valuable in predicting the risk of false positive of CPET in females with suspected CHD.Trial RegistrationThe present study is registered in Chinese Clinical Trial Register (ChiCTR2400089239).

B-314 Utility of he4 in differential diagnosis of pleural effusions

Abstract Background The usefulness of tumor markers in the differential diagnosis of cancer in patients with pleural effusions (PE) remains controversial. Few studies have reported the measurement of human epididymal protein 4 (HE4) in pleural fluid. HE4 is a tumor marker associated with different types of cancer. An elevated serum concentration has been observed in ovarian and lung cancers. Other benign pathologies can increase HE4 levels, which can be detect with different laboratory tests identified with adenosine deaminase (ADA), C-reactive protein (CRP), % polynuclear cell count (%PMN) and glomerular filtration rate (GFR) can be used in order to detect possible false positives. The objective of this study was to assess the diagnostic usefulness of HE4 in malignant pleural effusions by comparing HE4 concentrations between benign and malignant samples, while considering the causes of HE4 false positives. Methods HE4, ADA, differential leukocyte count, CRP and GFR concentrations were determined in 238 pleural effusion samples. Diagnostic efficacy analysis using receiver operating curves (ROC) identified the ability of HE4 to detect malignancy, searching for cut-off points with 100% specificity. Results HE4 concentrations showed significant differences (P<0.01) between malignant (median 1065pmol/L) and benign (median 699pmol/L) pleural effusions. Significant differences (P<0.01) were found in HE4 concentrations for gynecological and lung cancer origin (median 7397 pmol/L and 5150 pmol/L respectively) and other malignant pleural effusions (median 1065 pmol/L). Patients with benign diseases with renal failure showed a higher HE4 concentration (median 964pmol/L) than in patients without these pathologies (median 696pmol/L) identified with GFR<30 mL/min. No differences were demonstrated in HE4 concentration levels using ADA, differential leukocyte count or CRP, so only glomerular filtration rate was considered cause of false positives. A sensitivity of 23% was obtained for HE4, with a cut-off point of 3050pmol/L and a specificity of 100% for the whole group. In the potential false positive group, the sensitivity of HE4 was 28% with a cutoff point of 3050 pmol/L with a specificity of 100%. In the group without potential false positives, we obtained a sensitivity of 30% with a specificity of 100% for a cutoff point of 1992pmol/L. When we used a specific cut-off point for each group, we obtained a sensitivity of 38% with a specificity of 100%. Conclusions HE4 levels are higher in malignant pleural effusions compared to other pathologies. HE4 levels allow the identification of malignant pleural effusions with moderate sensitivity and maximum specificity. HE4 levels can differentiate between tumors of gynecological or lung origin and others. Glomerular filtration rate (GFR<30 mL/min) was considered the main cause of false positives. If we identify possible false positives, we can use specific cut-offs and improve sensitivity up to 38% with maximum specificity compared to using a single cut-off for all effusions.

Aortic isthmus flow reversal in fetal coarctation of the aorta and the associated factors.

The aim of this study was to investigate the presence of aortic isthmus flow reversal and its associated factors in fetuses with positive and false-positive coarctation of the aorta (CoA) compared with normal controls. Pregnant women with fetuses suspected of CoA and normal control were enrolled, and these women experienced prenatal ultrasound scan and followed up for 6 months after birth to confirm the presence of CoA. All the ultrasound parameters were analyzed. A total of 134 pregnant women were enrolled, with 43 CoA-positive fetuses and 91 CoA false-positive fetuses, and 334 matched pregnant women were enrolled in the control group. Aortic isthmus flow reversal occurred in 28 (65.1%) fetuses in the CoA-positive group, significantly (p < 0.05) more than in the false-positive (37 or 40.7%) or control group (64 or 19.2%). Aortic isthmus flow reversal was mostly in the full systole (n = 17 or 60.7%) or late systole and early-middle diastole (n = 10 or 35.7%) in the CoA-positive fetuses (n = 27 or 96.4%), significantly (p < 0.001) different from that in the false-positive or control group. The aortic isthmus flow reversal peak systolic velocity (PSV), flow volume, and ratio of reversed flow/forward flow were significantly (p < 0.05) increased in the CoA-positive and false-positive groups than in the control group. The aortic isthmus flow reversal incidence was significantly (p < 0.05) correlated with the middle cerebral artery (MCA) PSV in the total three groups or in the false-positive group but was significantly (p < 0001) negatively correlated with the MCA resistance index (RI) in the CoA-positive group. The incidence of the aortic isthmus flow reversal was significantly (p < 0.05) positively correlated with the umbilical artery (UA) RI in the false-positive group and with the UA RI in the total three groups. Independently associated factors for aortic isthmus flow reversal were isthmic flow volume/CCO (combined cardiac output) in the CoA-positive group. Reversal of flow in the aortic isthmus is much more common in true-positive cases of CoA as compared to controls, and isthmic flow reversal in the full systolic phase only suggests presence of CoA. The aortic isthmic reversed flow volume accounts for over half of the isthmic forward flow volume in the CoA-positive fetuses than in the normal controls.

Factors Associated with False Positive Breast Cancer Results in the Real-Time Sonoelastography Evaluation of Solid Breast Lesions.

Background and Objectives: Breast cancer is one of the most widespread cancers among the female population around the world and is curable if diagnosed in an early stage. Consequently, breast cancer screening imaging techniques have greatly evolved and adjusted over the last decades. Alongside mammography, sonoelastography became an important tool for breast cancer detection. However, sonoelastography still has its limitations, namely, there is still a high occurrence of false positive results in the BIRADS 4 category. The aim of our study is to identify potential false positive predictors and to ascertain the factors influencing the quality of strain ultrasound elastography for the evaluation of suspicious solid breast lesions categorized as BIRADS 4B, 4C, and 5. Materials and Methods: We conducted a retrospective study in a single private medical center in Timisoara between January 2017 and January 2022 analyzing 1625 solid breast lesions by the sonoelastography strain using a standardized BIRADS-US lexicon. Results: Our study showed that most sonoelastography factors linked to incorrect and overdiagnosis were due to a nodule dimension (OR = 1.02 per unit increase), posterior acoustic shadowing (OR = 12.26), reactive adenopathy (OR = 6.35), and an increased TES score (TES3 OR = 6.60; TES4 OR = 23.02; TES5 OR = 108.24). Regarding patient characteristics, age (OR = 1.09 per unit increase), BMI, (OR = 1.09 per unit increase), and breastfeeding history (OR = 3.00) were observed to increase the likelihood of false positive results. On the other hand, the nodules less likely to be part of the false positive group exhibited the following characteristics: a regular shape (OR = 0.27), homogenous consistency (OR = 0.42), and avascularity (OR = 0.22). Conclusions: Older age, high BMI, patients with a breastfeeding history, and those who exhibit the following specific nodule characteristics were most often linked to false positive results: large tumors with posterior acoustic shadowing and high elasticity scores, accompanied by reactive adenopathy. On the other hand, homogenous, avascular nodules with regular shapes were less likely to be misdiagnosed.

Smoking exposure and Parkinson's disease: A UK Brain Bank pathology-validated case-control study

IntroductionEpidemiological studies have consistently shown an inverse association between cigarette smoking and Parkinson's disease. Literature indicates that both current and former smokers have a reduced risk of developing PD compared to non-smokers. If smoking protects against Parkinson's disease risk or, conversely, smoking habit is abated due to the disease itself, according to the reverse causation, is still an unsolved question. Methods118 patients from the UK Brain Bank with an alive clinical diagnosis of Parkinson's disease were enrolled. Post-mortem validation served as the gold standard for diagnosis to divide the population into true positive and false positive groups. Patient charts were reviewed to extract smoking exposure information and statistical analyses were conducted to determine the odds associated with smoking in the two diagnostic groups. ResultsAmong alive clinically diagnosed patients with Parkinson's disease, 53 % had no smoking exposure. In the True Positive group, 58 % had no smoking exposure, while this proportion was lower in the False Positive group at 46 %. The Odds Ratio for the association between smoking exposure and the two groups was 0.63 (95 % CI: 0.32–1.37). The Chi-square test yielded a p-value of 0.2804. ConclusionsOur findings emphasize the role of smoking exposure in Parkinson's diagnosis. The results indicate that the observed association is not specific to idiopathic Parkinson's disease but rather a broader phenomenon encompassing various parkinsonian disorders. This suggests a potential common neuroprotective effect of smoking, shared risk factors, or supports the reverse causation hypothesis where parkinsonian symptoms reduce smoking exposure.

Factors influencing false-positive results of rifampicin resistance detected by Xpert MTB/RIF: A retrospective study in Zhejiang, China

ObjectiveThis study aimed to explore the factors influencing false-positive results for rifampicin resistance (RIF-R) detected using Xpert MTB/RIF (Xpert). MethodsThis retrospective analysis included the clinical data of patients from September 2019 to February 2023. The chi-square and rank sum tests were used to compare differences in patient characteristics between the true-positive and false-positive groups. Logistic regression was used to analyze the factors influencing false positives in the detection of RIF-R by Xpert. ResultsA total of 384 patients were included. Logistic regression analysis revealed that, with mutation of probe E as the reference, mutations on probe A or C (OR = 72.68, P < 0.001), probe D (OR = 6.44, P < 0.001), and multiple probes (OR = 5.94, P = 0.002) were associated with false-positive results in Xpert detection of RIF-R. Taking probe delay ΔCt <4 as the reference, ΔCt (4–5.9) (OR = 13.54, P < 0.001), ΔCt (6–7.9) (OR = 48.08, P < 0.001) probe delays were associated with false positives in Xpert detection of RIF-R. When very low quantification is accompanied by a probe delay, the probability of false-positive RIF-R detection can reach 80 %. ConclusionsClinicians should consider factors such as probe mutation type, probe delay, and very low quantification accompanied by probe delay when interpreting Xpert results, which can reduce the misdiagnosis of tuberculosis drug resistance.

A simulation study to assess the potential benefits of MRI-based fetal weight estimation as a second-line test for suspected macrosomia

ObjectiveTo simulate the outcomes of Boulvain’s trial by using magnetic resonance imaging (MRI) for estimated fetal weight (EFW) as a second-line confirmatory imaging. Study designData derived from the Boulvain’s trial and the study PREMACRO (PREdict MACROsomia) were used to simulate a 1000-patient trial. Boulvain’s trial compared induction of labor (IOL) to expectant management in suspected macrosomia, whereas PREMACRO study compared the performance of ultrasound-EFW (US-EFW) and MRI-EFW in the prediction of birthweight. The primary outcome was the incidence of significant shoulder dystocia (SD). Cesarean delivery (CD), hyperbilirubinemia (HB), and IOL at < 39 weeks of gestation (WG) were selected as secondary outcomes. A subgroup analysis of the Boulvain’s trial was performed to estimate the incidence of the primary and secondary outcomes in the true positive and false positive groups for the two study arms. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) for the prediction of macrosomia by MRI-EFW at 36 WG were calculated, and a decision tree was constructed for each outcome. ResultsThe PPV of US-EFW for the prediction of macrosomia in the PREMACRO trial was 56.3 %. MRI-EFW was superior to US-EFW as a predictive tool resulting in lower rates of induction for false-positive cases. Repeating Boulvain’s trial using MRI-EFW as a second-line test would result in similar rates of SD (relative risk [RR]:0.36), CD (RR:0.84), and neonatal HB (RR:2.6), as in the original trial. Increasing the sensitivity and specificity of MRI-EFW resulted in a similar relative risk for SD as in Boulvain’s trial, but with reduced rates of IOL < 39 WG, and improved the RR of CD in favor of IOL. We found an inverse relationship between IOL rate and incidence of SD for both US-EFW and MRI-EFW, although overall rates of IOL, CD, and neonatal HB would be lower with MRI-derived estimates of fetal weight. ConclusionThe superior accuracy of MRI-EFW over US-EFW for the diagnosis of macrosomia could result in lower rates of IOL without compromising the relative advantages of the intervention but fails to demonstrate a significant benefit to justify a replication of the original trial using MRI-EFW as a second-line test.

Strategic Retesting to Reduce False Positive SARS-CoV-2 PCR Test Results.

Nucleic acid amplification testing is the gold standard for SARS-CoV-2 diagnostics, although it may produce a certain number of false positive results. There has not been much published about the characteristics of false positive results. In this study, based on retesting, specimens that initially tested positive for SARS-CoV-2 were classified as true or false positive groups to characterize the distribution of cycle threshold (CT) values for N1 and N2 targets and number of targets detected for each group. Specimens that were positive for N-gene on retesting and accompanied with S-gene were identified as true positives (true positive based on retesting, rTP), while specimens that retested negative were classified as false positives (false positive based on retesting, rFP). Of the specimens retested, 85/127 (66.9%) were rFP, 16/47 (34.0%) specimens with both N1 and N2 targets initially detected were rFP, and the CT values for each target was higher in rFP than in rTP. ROC curve analysis showed that optimal cutoff values of CT to differentiate between rTP and rFP were 34.8 for N1 and 33.0 for N2. With the optimal cutoff values of CT for each target, out of the 24 specimens that were positive for both N1 and N2 targets and classified as rTP, 23 (95.8%) were correctly identified as true positives. rFP specimens had a single N1 target in 52/61 (85.2%) and a single N2 target in 17/19 (89.5%). Notably, no true positive results were obtained from any specimens with only N2 target detected. These results suggest that retesting should be performed for positive results with a CT value greater than optimal cutoff value for each target or with a single N1 target amplified, considering the possibility of a false positive. This may provide guidance on indications to perform retesting to minimize the number of false positives.

Diagnostic yield of bronchoscopic rapid on-site evaluation in severe invasive bronchopulmonary aspergillosis

To explore the diagnostic yield of bronchoscopic rapid on-site evaluation (B-ROSE) in patients with severe invasive bronchopulmonary aspergillosis (IBPA) and provide evidence for starting antifungal treatment before microbiological results were available. A prospective cohort study was conducted to select patients with severe pneumonia suspected of IBPA admitted to the respiratory intensive care unit (RICU) in the First Affiliated Hospital of Xinjiang Medical University from June 2014 to June 2022, and those who were primarily infected with other pathogens (such as bacteria, Mycobacterium tuberculosis) at admission were excluded. Whether the antifungal treatment was initiated or not on the basis of the bedside B-ROSE, the B-ROSE was administered as soon as possible within 24 hours after admission to RICU. The current international definition of invasive aspergillosis was used as the gold diagnostic standard, the diagnostic accordance rate, the sensitivity and specificity of B-ROSE were calculated respectively, and the receiver operator characteristic curve (ROC curve) was also plotted, to evaluate the predictive value in diagnosing IBPA. A total of 176 patients with severe pneumonia suspected of IBPA were included in the study. According to international diagnostic standards, there were 81 cases of IBPA and 95 cases of non-IBPA. According to the early diagnosis of B-ROSE, there were 89 cases of IBPA and 87 cases of non-IBPA. The diagnostic accordance rate of B-ROSE was 84.09% (148/176), the area under the ROC curve for B-ROSE in diagnosing severe IBPA was 0.844, the 95% confidence interval (95%CI) was 0.782-0.905, the sensitivity was 87.65%, the specificity was 81.05%, the positive predictive value was 79.78%, the negative predictive value was 88.51%, the rate of underdiagnosis was 12.35% (10/81), and the rate of misdiagnosis was 18.95% (18/95). Compared with the true negative group, the proportion of long-term (≥ 14 days) use of glucocorticoid [70.0% (7/10) vs. 9.1% (7/77), P < 0.01] and the proportion of cases with diabetes [40.0% (4/10) vs. 10.4% (8/77), P < 0.05] were significantly higher in the false negative group (underdiagnosis group). However, B-ROSE of both groups showed mucosal bleeding, congestion and edema [100.0% (10/10) vs. 94.8% (73/77), P > 0.05], indicating that acute mucosal inflammation was non-characteristic. Compared with the true positive group, the proportion of long-term (≥ 14 days) use of glucocorticoid in the false positive group (misdiagnosis group) was significantly reduced [33.3% (6/18) vs. 60.6% (43/71), P < 0.05]. The B-ROSE results showed the proportion of cases with mucosal white spots, black plaques and pseudomembrane was significantly reduced [16.7% (3/18) vs. 52.1% (37/71), P < 0.01] in the misdiagnosed group, which suggest that cases of long-term use of glucocorticoid and cases with B-ROSE showing mucosal white spots, black plaques and pseudomembrane were less likely to be misdiagnosed. The main diseases that were easily misdiagnosed as IBPA included pulmonary tuberculosis (38.9%, 7/18), inflammatory lung adenocarcinoma (27.8%, 5/18) and pulmonary vasculitis (16.7%, 3/18). Before obtaining microbiological evidence, B-ROSE can assist in decision-making of early anti-aspergillus treatment for severe IBPA. This method is prompt, simple, and has high accuracy and reliability. If B-ROSE lacks characteristic manifestations, especially for severe pneumonia in patients with long-term use of glucocorticoid or diabetes, attention should be paid to the underdiagnosis of IBPA. Diseases such as lung tuberculosis, inflammatory lung adenocarcinoma and lung vasculitis should be vigilant against misdiagnosis as IBPA.

False-positive supraclavicular lymph node detected on chest computed tomography in oncology patients: Clinical implication based on subsequent neck ultrasonography and ultrasonography-guided tissue sampling.

The purpose of this study was to assess the prevalence and clinical implications of false-positive supraclavicular lymph node (LN) detected on chest computed tomography (CT), using subsequent neck ultrasonography (US) and US-guided tissue sampling. Among 172 patients with suspected supraclavicular LNs identified on CT, 87 underwent neck US or US-guided tissue sampling. Receiver operating characteristic curve and logistic regression analyses were performed to determine the diagnostic performance of US and independent predictors of false-positive LNs. Among 87 patients, 49 (56.3%) were pathologically confirmed as metastases, 26 (29.9%) were negative for malignancy, and 12 (13.8%) had pseudolesions or schwannomas. The diagnostic indices were as follows: sensitivity, 91.8%; specificity, 92.3%; PPV, 95.7%; NPV, 85.7%; and accuracy, 92.0% (AUC = 0.921; 95% CI: 0.832-0.970, p < 0.001). The false-positive group had a higher mean age than the true-positive group (mean age, 69.8 ± 9.2 vs. 63.9 ± 9.8, p = 0.003). Logistic regression analyses revealed that age ≥ 65 years was the only independent predictor of false-positive LNs (OR = 4.391; 95% CI: 1.037-18.582; p = 0.044). Subsequent US can be helpful for evaluating suspicious supraclavicular LNs detected on CT to establish appropriate management, especially in older patients.

Magnetic resonance radiographic features which might lead to misdiagnosis of muscle-invasive bladder cancer based on vesical imaging reporting and data system: the application experience of a single center.

The Vesical Imaging Reporting and Data System (VI-RADS) has been widely used for diagnosing muscle-invasive bladder cancer (MIBC), yet instances of misdiagnosis persist. However, limited research discusses the factors affecting its accuracy. This study aimed to evaluate the diagnostic efficacy of the VI-RADS in our center and to preliminarily identify possible magnetic resonance imaging (MRI) characteristics of misdiagnosis. From January 2018 to February 2023, a consecutive series of 211 participants pathologically diagnosed with bladder cancer (BC) who underwent an MRI exam were retrospectively enrolled. MRI was interpreted by 2 radiologists with different levels of experience, the diagnostic performance was validated using the receiver operating characteristic (ROC) curve, and VI-RADS ≥4 was considered to indicate MIBC-positive status. The clinical and radiographic characteristics of the true-positive (TP), true-negative (TN), false-positive (FP), and false-negative (FN) groups were analyzed using Kruskal-Wallis test or Fisher exact test. With VI-RADS ≥4 as the cutoff value, the area under the ROC curves (AUCs) were 0.951 (0.912-0.976) and 0.847 (0.791-0.893) for the more-experienced reader and less-experienced reader, respectively, with good interobserver agreement (κ=0.74105). The median tumor size in the TP (more experienced: 57 cases; less experienced: 44 cases) and FP (more experienced: 8 cases; less experienced: 9 cases) groups was larger than that in the TN (more experienced: 141 cases; less experienced: 139 cases) group for the more-experienced reader (TP: 28 mm; FP: 31 mm; TN: 19 mm; P<0.001 and P=0.031, respectively) and the less-experienced reader (TP: 31 mm; FP: 28 mm; TN: 19 mm; P<0.001 and P=0.042, respectively). The tumor base in the TP and FP groups was larger than that in the TN group for the more-experienced reader (TP: 37 mm; FP: 48 mm; TN: 15 mm; both P<0.001) and for the less-experienced reader (FP: 42 mm; FP: 36 mm; TN: 15 mm; P<0.001 and P=0.022, respectively). The median tumor base in the TP group was larger than that in the FN group for the less-experienced reader (TP: 42 mm; FN: 17 mm; P=0.004). We observed good to excellent AUCs with good interobserver agreement among radiologists with different levels of expertise using VI-RADS. Large tumor size and wide tumor base affected the accuracy of VI-RADS in MIBC diagnosis.

Evaluation of 18-FDG PET diagnostic capabilities for cancer screening in heart transplant patients, a retrospective study.

Evaluate 18-FDG positron emission tomography (PET) diagnostic capabilities for cancer screening in heart transplant patients. We conducted an anonymized retrospective observational study of heart transplant patients followed in the University Hospital of Montpellier, France. We analyzed 303 18-FDG PET from 158 patients. We compared demographic and clinical characteristics through uni- and multivariate analysis: in the cancer-free group, comparisons were made between the PET false positive (FP) group versus true negative (TN), and in the cancer group, comparisons were made between the PET false negative (FN) group versus true positive (TP). Out of the 303 exams, we found 245 TN, 26 TP, 26 FP and 6 FN. The sensitivity rate was calculated at 81%, the specificity rate at 90%, the positive predictive value at 50%, and the negative predictive value at 97%. The multivariate analysis showed an association between FP diagnosis and graft-PET delay (P value = .046, OR = 5.14, 95% CI [1.18-32.4]) and creatine reactive protein (CRP) ≥ 10 mg/L (P value = .042, OR = 4.21, 95% CI [1.02-17.2]). The estimated probability of FP by logit regression was 0.48 with 95% CI [0.21-0.77] when graft-PET delay ≥ 6 years and CRP ≥ 10 mg/L. No significative statistical link was found for the demographic or clinical characteristics in the FN group of patients with cancer, except for sex (all FN were men). 18-FDG PET performed very well in the follow-up of heart transplant patients for neoplasia screening, with better specificity than sensitivity. However, the study showed that almost 50% of FP can be predicted by considering only the graft-PET delay and CRP.

Are false positives in suicide classification models a risk group? Evidence for "true alarms" in a population-representative longitudinal study of Norwegian adolescents.

False positives in retrospective binary suicide attempt classification models are commonly attributed to sheer classification error. However, when machine learning suicide attempt classification models are trained with a multitude of psycho-socio-environmental factors and achieve high accuracy in suicide risk assessment, false positives may turn out to be at high risk of developing suicidal behavior or attempting suicide in the future. Thus, they may be better viewed as "true alarms," relevant for a suicide prevention program. In this study, using large population-based longitudinal dataset, we examine three hypotheses: (1) false positives, compared to the true negatives, are at higher risk of suicide attempt in future, (2) the suicide attempts risk for the false positives increase as a function of increase in specificity threshold; and (3) as specificity increases, the severity of risk factors between false positives and true positives becomes more similar. Utilizing the Gradient Boosting algorithm, we used a sample of 11,369 Norwegian adolescents, assessed at two timepoints (1992 and 1994), to classify suicide attempters at the first time point. We then assessed the relative risk of suicide attempt at the second time point for false positives in comparison to true negatives, and in relation to the level of specificity. We found that false positives were at significantly higher risk of attempting suicide compared to true negatives. When selecting a higher classification risk threshold by gradually increasing the specificity cutoff from 60% to 97.5%, the relative suicide attempt risk of the false positive group increased, ranging from minimum of 2.96 to 7.22 times. As the risk threshold increased, the severity of various mental health indicators became significantly more comparable between false positives and true positives. We argue that the performance evaluation of machine learning suicide classification models should take the clinical relevance into account, rather than focusing solely on classification error metrics. As shown here, the so-called false positives represent a truly at-risk group that should be included in suicide prevention programs. Hence, these findings should be taken into consideration when interpreting machine learning suicide classification models as well as planning future suicide prevention interventions for adolescents.

Xpert Bladder Cancer Monitor for the Early Detection of Non-Muscle Invasive Bladder Cancer Recurrences: Could Cystoscopy Be Substituted?

XBM was prospectively assessed in spontaneous urine collected just before flexible cystoscopy and washing cytology carried out within the first 2 years follow-up of 337 patients with NMIBC. Recurrences were pathologically confirmed in 49 patients (14.5%), 22 of them being high-risk (6.5%). The XBM sensitivity for detecting any type of recurrence was 69.4% and 63.6% in the cases of high-risk NMIBC. Negative predictive value (NPV) for XBM was 93% for all recurrences and 96.2% for high-risk recurrences. XBM could have avoided 213 invasive controls but missed the detection of 15 recurrences (30.6%)-8 of them of high-risk (36.4%). XBM false positive elevations were detected in 90 patients (26.7%), whereas 10 patients with the invasive method had a false positive result (3%), p <0.001. However, early detection of recurrences during the first year's follow-up after an XBM false positive result was observed in 18 patients (20%). On the other hand, 19 recurrences were detected during this period among the rest of the patients (7.7%)-p = 0.003, and odds ratio (OR) 3.0 (95% CI 1.5-6.0). Regarding one-year follow-up recurrences, 10% were high-risk recurrences in the XBM false positive group and 3.2% in the rest of the patients-p = 0.021, and OR 3.3 (95% CI 1.2-8.9). Additionally, 11.3% of the patients without false positive results developed a recurrence, p = 0.897, for any recurrence, being 10% and 5.2%, respectively, and high-risk and low-risk recurrences, p = 0.506. After searching for the best XBM cutoff for detecting the 38 high-risk initial recurrences and the early high-risk recurrences after a one-year follow-up, a linear discriminant analysis (LDA) of 0.13 could have avoided 11.3% of cystoscopies and bladder wash cytologies, as this cutoff missed only 1 high-risk recurrence (2.6%). More extensive and well-designed studies will confirm if XBM can improve the surveillance of NMIBC.

FraudAuditor: A Visual Analytics Approach for Collusive Fraud in Health Insurance.

Collusive fraud, in which multiple fraudsters collude to defraud health insurance funds, threatens the operation of the healthcare system. However, existing statistical and machine learning-based methods have limited ability to detect fraud in the scenario of health insurance due to the high similarity of fraudulent behaviors to normal medical visits and the lack of labeled data. To ensure the accuracy of the detection results, expert knowledge needs to be integrated with the fraud detection process. By working closely with health insurance audit experts, we propose FraudAuditor, a three-stage visual analytics approach to collusive fraud detection in health insurance. Specifically, we first allow users to interactively construct a co-visit network to holistically model the visit relationships of different patients. Second, an improved community detection algorithm that considers the strength of fraud likelihood is designed to detect suspicious fraudulent groups. Finally, through our visual interface, users can compare, investigate, and verify suspicious patient behavior with tailored visualizations that support different time scales. We conducted case studies in a real-world healthcare scenario, i.e., to help locate the actual fraud group and exclude the false positive group. The results and expert feedback proved the effectiveness and usability of the approach.

The Screening of Celiac Serology in Pediatric Patients Diagnosed with Type 1 Diabetes Mellitus.

This study aims to detect the rate of celiac antibody test positivity in pediatric patients diagnosed with type 1 diabetes mellitus (T1DM) and determine the characteristics of the patient groups diagnosed with and without celiac disease (CD). This study was conducted retrospectively in Adana City Training and Research Hospital, Pediatric Endocrinology Outpatient Clinic with the patients diagnosed with T1DM between September 17, 2017, and January 1, 2022. The patients were examined by 3 different groups. Group 1: celiac patient group, group 2: serology false positive group, and group 3: serology negative group. The study included 418 patients, 228 (54.5%) males and 190 (45.5%) females. About 6% of the patients (25 patients) were in the celiac patient group, 12.6% (53 patients) in the serology false positive group, and 81.3% (340 patients) in the serology negative group. The age at diagnosis was 10 (7.2-12.9) years in the celiac patient group and 8.8 (6.2-12.00) years in the serology false positive group (P = .559). Among 53 patients in the serology false positive group, spontaneous normalization was observed in 66% (35 patients), and positivity was continued during the test follow-up period in 34% (18 patients). There was no significant difference in terms of sex (P = .101), and HbA1c values at diagnosis (P = .557). Tissue transglutaminase IgA titer was 20× Upper limit of normal (ULN) in the celiac patient group and 2.52× ULN in the serology false positive group. T1DM and CD are both autoimmune diseases concurrently seen together. CD antibody positivity may be observed at the first presentation of T1DM. While the majority of these antibodies become negative during the follow-up, we wanted to highlight the false positive antibody titers and emphasize that these patients should be followed by endocrinologists and gastroenterologists together.

Analysis of Risk Factors and Screening Results of Neonatal Congenital Hypothyroidism in a Tertiary Care Center of Southern China.

To explore the risk factors for neonatal congenital hypothyroidism (CH) and the influencing factors of false-positive results in CH screening. In this study, 255 neonatal patients with CH who completed the screening and further diagnosis and 366 neonates with positive CH screening results and normal thyroid function were selected as the case group. 246 healthy neonates with normal thyroid function were selected as the control group. Gestational age, birth-weight, maternal age, small for gestational age (SGA), perinatal factors (gestational thyroid dysfunction, gestational diabetes mellitus, etc.) were used as influencing factors, using χ 2 tests were performed for comparison. The statistically significant variables were analyzed with Logistic multiple regression models, and the difference was considered statistically significant (P<0.05). There were statistical differences in the SGA, maternal gestational diabetes mellitus, thyroid disease, and the proportion using assisted reproduction technology among the case group, false-positive screening group, and control group (χ 2 was 11.943, 6.857, 6.999, 9.732, respectively, P < 0.05). The results of multivariate logistic regression analysis showed that the gestational thyroid disease (OR = 8.452, 95% CI:1.051-67.982), gestational diabetes mellitus (OR = 2.654, 95% CI:1.051-6.706), and assisted reproduction (OR = 0.194, 95% CI:0.041-0.911) were the influencing factors for neonatal CH, and the difference was statistically significant (P < 0.05). The SGA (OR = 2.556, 95% CI:1.027-6.361), gestational thyroid disease (OR = 7.801, 95% CI:1.03-59.057), gestational diabetes mellitus (OR = 2.731, 95% CI:1.18-6.322), and assisted reproduction (OR = 0.28, 95% CI:0.102-0.765) were the influencing factors of the false-positive screening results of neonatal CH. The difference was statistically significant (P < 0.05). Neonatal CH and positive screening results are influenced by assisted reproduction, gestational thyroid dysfunction, gestational diabetes mellitus, and SGA.

Characterization of Hemodynamic Alteration in Parkinson's Disease and Effect on Resting-State Connectivity

Functional magnetic resonance imaging (fMRI) is a convolution of latent neural activity and the hemodynamic response function (HRF). According to prior studies, the neurodegenerative process in idiopathic Parkinson's Disease (PD) interacts significantly with neuromuscular abnormalities. Although these underlying neuromuscular changes might influence the temporal characteristics of HRF and fMRI signals, relatively few studies have explored this possibility. We hypothesized that such alterations would engender changes in estimated functional connectivity (FC) in fMRI space compared to latent neural space. To test these theories, we calculated voxel-level HRFs by deconvolving resting-state fMRI data from PD patients (n = 61) and healthy controls (HC) (n = 47). Significant group differences in HRF (P < 0.05, Gaussian random field-corrected) were observed in several regions previously associated with PD. Subsequently, we focused on putamen-seed-based FC differences between the PD and HC groups using fMRI and latent neural signals. The results suggested that neglecting HRF variability may cultivate false-positive and false-negative FC group differences. Furthermore, HRF was related to dopamine receptor type 2 (DRD2) gene expression (P < 0.001, t = −7.06, false discover rate-corrected). Taken together, these findings reveal HRF variation and its possible underlying molecular mechanism in PD, and suggest that deconvolution could reduce the impact of HRF variation on FC group differences.

Relationship between False Positive Screening Results of Down Syndrome and Adverse Pregnancy Outcomes.

Maternal serum sample screening in the first and second trimesters has been commonly used to identify women who are at risk of fetal trisomy 21. In addition, these serum markers are associated with adverse perinatal outcomes. Hence, the present study was conducted to determine the relationship between false positive screening results of Down syndrome and adverse pregnancy outcomes. This prospective, two-group, cohort study was conducted on 608 pregnant women who had undergone fetal contingent screening. They were selected through convenience sampling in the twentieth week of pregnancy and were followed up until delivery. The raw Odd Ratios (OR), Relative Risk (RR), and adjusted OR of adverse pregnancy outcomes were calculated in the false positive and true negative groups. The adjusted OR of developing preeclampsia was 1.98 (95%CI: 1.14-3.42), and its RR was 2.13 (95%CI: 1.34-3.38) times higher in the false positive group. Moreover, the adjusted OR of Small for Gestational Age (SGA) was 2.80 (95%CI: 1.76-4.47), and its RR was 2.28 (95%CI: 1.54-3.36) times higher in the false positive group. The adjusted OR of Low Birth Weight (LBW) was 3.34 (95%CI: 1.97-5.64), and its RR was 2.65 (95%CI: 1.72-4.11) times higher in the false positive group. In addition, no significant difference was observed between false positive and true negative groups in terms of preterm birth. Women with a false positive fetal screening test result are more likely to suffer from preeclampsia, SGA, and LBW and require planned prenatal care.

Study on the correlation between false-positive filling defect in LAA CT and LAA structure in patients with atrial fibrillation based on TEE.

This study aims to explore the actual meaning of "false positive filling defect" in left atrial appendage (LAA) computed tomography (CT) in patients with atrial fibrillation (AF), with transesophageal echocardiography (TEE) as the gold standard. Patients with AF undergoing cardiac CT angiography and TEE examinations for proposed radiofrequency catheter ablation between October 2020 and October 2021 were selected as the study subjects. Transesophageal echocardiography was taken as the "gold standard," and spontaneous echocardiographic contrast (SEC) and thrombus events were defined as positive events. The CT manifestations were classified into three groups (true positive, false positive, and true negative) to evaluate the differences in left atrium (LA) anterior-posterior diameter (LAAP), LA anterior wall thickness, and LAA orifice long diameter and short diameter, area, and depth between the three groups. (1) There was no statistical difference in LA anterior wall thickness between the three groups (p > .05); there was a statistical difference in LAAP (only) between the true-positive group and the true-negative group (p < .05). (2) There was a statistical difference in LAA orifice long diameter, short diameter, and area between the true-positive group and the true-negative group as well as between the false-positive group and the true-negative group (p < .05). (3) There was a statistical difference in LAA depth between the true-positive group and the false-positive group as well as between the true-positive group and the true-negative group (p < .05). (4) The area under the receiver operator characteristic curve (AUC) of LAA depth affecting the LAA thrombus and SEC was 0.863 (confidence interval=0.718-1.000), the sensitivity was 77.8%, and the specificity was 90.6% for predicting the occurrence of LAA thrombus and SEC in patients with nonvalvular AF (NVAF) and an LAA depth of ≥50.84 mm. There was a difference in LAA diameter between the TEE-based CT false-positive group and the other groups. A "CT false positive" is an objectively existing state, and CT might be able to identify the LAA hemodynamic disorder earlier than TEE. Furthermore, a CT + TEE combined application could more accurately evaluate LAA hemodynamics in patients with AF.