Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR wer...Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR were assessed in 690 Chinese adults (305 men and 385 women) and compared with magnetic resonance imaging (MRI) measurements of abdominal visceral adipose tissue (VA). Receiver operating characteristic (ROC) curves were generated and used to determine the threshold point for each anthropometric parameter. Results 1) MRI showed that 61.7% of overweight/obese individuals (BMI≥25 kg/m2) and 14.2% of normal weight (BMI<25 kg/m2) individuals had abdominal visceral obesity (VA≥100 cm2). 2) VA was positively correlated with each anthropometric variable, of which WC showed the highest correlation (r=0.73-0.77, P<0.001). 3) The best cut-off points for assessing abdominal visceral obesity were as followed: BMI of 26 kg/m2, WC of 90 cm, and WHR of 0.93, with WC being the most sensitive and specific factor. 4) Among subjects with BMI≥28 kg/m2 or WC≥95 cm, 95% of men and 90% of women appeared to have abdominal visceral obesity. Conclusion Measurements of BMI, WC, and WHR can be used in the prediction of abdominal visceral obesity, of which WC was the one with better accuracy.展开更多
Objective: To determine the endemic values of cutaneous leishmaniasis in different cities of Fars province, Iran. Methods: Totally, 29 201 cases registered from 2010 to 2015 in Iranian Fars province were selected, and...Objective: To determine the endemic values of cutaneous leishmaniasis in different cities of Fars province, Iran. Methods: Totally, 29 201 cases registered from 2010 to 2015 in Iranian Fars province were selected, and the endemic values of cutaneous leishmaniasis were determined by retrospective clusters derived from spatiotemporal permutation modeling on a time-series design. The accuracy of the values was assessed using receiver operating characteristic(ROC) curve. SPSS version 22, Arc GIS, and ITSM 2002 software tools were used for analysis. Results: Nine statistically significant retrospective clusters(P<0.05) resulted in finding seven significant and accurate endemic values(P<0.1). These valid endemic scores were generalized to the other 18 cities based on 6 different climates in the province. Conclusions: Retrospectively detected clusters with the help of ROC curve analysis could help determine cutaneous leishmaniasis endemic values which are essential for future prediction and prevention policies in the area.展开更多
Aim: To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods: The accuracy of the spectrophotometric application of the resazurin reduction assay was asses...Aim: To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods: The accuracy of the spectrophotometric application of the resazurin reduction assay was assessed using receiver operating characteristic (ROC) analysis. Results: Areas under ROC curves (AUC) for motile sperm concentration and sperm index (SI) (sperm concentration multiplied by the square root of percentage sperm motility multiplied by the percentage normal sperm morphology) were 0.922. The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A610 = 0.209, where high sensitivity (94.1%) and specificity (91.7%) were calculated. The assay was less accurate when motile sperm concentration was used as the criterion value, yielding sensitivity of 88.2% and specificity of 87.5%, respectively. Likelihood ratios (LR) indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI, whereas in the case of motile sperm concentration, the LR was calculated to be 7.06. Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.展开更多
Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in di...Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in diverse symptoms including chronic cough, throat cleaning and dysphonia (e.g. hoarseness). In turn, the dysphonic symptoms can be evaluated via subjective and objective procedures. The objective procedures usually include self-perceived questionnaires like the Voice Handicap Index (VHI). Studies reported that VHI can distinguish objectively dysphonic and non-dysphonic populations using the cut-off points of Receiver Operating Characteristic Curves. The purpose of this study was to calculate the cut-off points for individuals exhibiting voice symptoms which had been developed from laryngeal inflammatory diseases in Greece. Methods: One hundred and twelve participants (90 non-dysphonic and 22 dysphonic) filled in the Hellenic Voice Handicap Index (VHI) and the Greek translated version of Voice Evaluation Template (VEF) were administrated. All subjects were evaluated by an Otolaryngologist and a Speech-Language Pathologist. Results: The group with voice disorders exhibited higher VHI scores (in total and in its 3 subdomains) compared to non-dysphonic subgroup. Statistical significant differences were found for all VHI’s total cut-off point of 19.50 (sensitivity: 0.882, 1-specificity: 0.011) and for its three subdomains [functional 6.50 (sensitivity = 0.636, and 1-specificity = 0.022);physical 9.50 (sensitivity = 0.636, and 1-specificity = 0.000);emotional 6.50 (sensitivity = 0.455, and 1-specificity = 0.133)]. Conclusion: The preliminary results showed that VHI could discriminate individuals having voice disorders from laryngeal inflammations. The Voice Handicap Index can be used as a primary health care tool and a self-monitoring procedure in acute and sub-acute phases of the laryngeal inflammation.展开更多
Objective: To determine the clinical serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), individually and in combination, for the diagnosis of 50 healthy subjects and 150 cases ...Objective: To determine the clinical serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), individually and in combination, for the diagnosis of 50 healthy subjects and 150 cases of esophageal, gastric, and colon cancers. Methods: The sensitivities of the two markers were compared individually and in combination, with specificity set at 100%. Receiver operating characteristic (ROC) curves were plotted. Results: Serum CEA levels were significantly higher in cancer patients than in the control group. The sensitivity of CEA was determined: in esophageal cancer, sensitivity=28%, negative predictive value (NPV)=61.72%, and AUC=0.742 (SE=0.05), with a significance level of P〈0.0001; in gastric cancer, sensitivity=30%, NPV=58.82%, and AUC=0.734 (SE=0.0S), with a significance level of P〈0.0001; in colon cancer, sensitivity=74%, NPV=79.36%, and AUC=0.856 (SE=0.04), with a significance level of P〈0.0001. The sensitivity of CA19-9 was also evaluated: in esophageal cancer, sensitivity=18%, NPV=54.94%, and AUC=0.573 (SE=0.05), with a significance level of P=0.2054. In gastric cancer, sensitivity=42%, NPV=63.29%, and AUC=0.679 (SE=0.05), with a significance level of P〈0.0011. In colon cancer, sensitivity=26%, NPV=57.47%, and AUC=0.S80 (SE=0.05), with a significance level ofP=0.1670. The following were the sensitivities of CEA/CA19-9 combined: in esophageal cancer, sensitivity=42%, NPV=63.29%, SE=0.078 (95% CI: 0.0159-0.322); gastric cancer, sensitivity=S8%, NPV=70.42%, SE=0.072 (9$% CI: -0.0866-0.198); and colon cancer, sensitivity=72%, NPV=78.12%, SE=0.070 (9S% CI: 0.137-0.415). Conclusion: CEA exhibited the highest sensitivity for colon cancer, and CA19-9 exhibited the highest sensitivity for gastric cancer. Combined analysis indicated an increase in diagnostic sensitivity in esophageal and gastric cancer compared with that in colon cancer.展开更多
BACKGROUND Colorectal cancer(CRC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many patients.The early detection and diagnosi...BACKGROUND Colorectal cancer(CRC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many patients.The early detection and diagnosis of CRC are crucial for improving treatment success and patient survival rates.Recently,imaging techniques have been hypothesized to be essential in managing CRC,with magnetic resonance imaging(MRI)and spiral computed tomography(SCT)playing a significant role in enhancing diagnostic and treatment approaches.AIM To explore the effectiveness of MRI and SCT in the preoperative staging of CRC and the prognosis of laparoscopic treatment.METHODS Ninety-five individuals admitted to Zhongshan Hospital Xiamen University underwent MRI and SCT and were diagnosed with CRC.The precision of MRI and SCT for the presurgical classification of CRC was assessed,and pathological staging was used as a reference.Receiver operating characteristic curves were used to evaluate the diagnostic efficacy of blood volume,blood flow,time to peak,permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction on the prognosis of patients with CRC.RESULTS Pathological biopsies confirmed the following CRC stages:23,23,32,and 17 at T1,T2,T3,and T4,respectively.There were 39 cases at the N0 stage,22 at N1,34 at N2,44 at M0 stage,and 51 at M1.Using pathological findings as the benchmark,the combined use of MRI and SCT for preoperative TNM staging in patients with CRC demonstrated superior sensitivity,specificity,and accuracy compared with either modality alone,with a statistically significant difference in accuracy(P<0.05).Receiver operating characteristic curve analysis revealed the predictive values for laparoscopic treatment prognosis,as indicated by the areas under the curve for blood volume,blood flow,time to peak,and permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction were 0.750,0.683,0.772,0.761,0.709,0.719,and 0.910,respectively.The corresponding sensitivity and specificity values were also obtained(P<0.05).CONCLUSION MRI with SCT is effective in the clinical diagnosis of patients with CRC and is worthy of clinical promotion.展开更多
BACKGROUND Hepatic metastases are common and difficult to treat after colorectal cancer(CRC)surgery.The predictive value of carcinoembryonic antigen(CEA),cancer antigen(CA)125 and CA19-9 combined tests for liver metas...BACKGROUND Hepatic metastases are common and difficult to treat after colorectal cancer(CRC)surgery.The predictive value of carcinoembryonic antigen(CEA),cancer antigen(CA)125 and CA19-9 combined tests for liver metastasis is unclear.AIM To evaluate predictive value of combined tests for CEA,CA125,and CA19-9 levels in patients with liver metastases of CRC.METHODS The retrospective study included patients with CRC alone(50 cases)and patients with CRC combined with liver metastases(50 cases)who were hospitalized between January 2021 and January 2023.Serum CEA,CA125 and CA19-9 levels were compared between the two groups,and binary logistic regression was used to analyze the predictive value of the combination of these tumor markers in liver metastasis.In addition,we performed receiver operating characteristic(ROC)curve analysis to assess its diagnostic accuracy.RESULTS The results showed that the serum CEA,CA125 and CA19-9 levels in the CRC with liver metastasis group were significantly higher than those in the CRC alone group.Specifically,the average serum CEA level in the CRC with liver metastasis group was 162.03±810.01 ng/mL,while that in the CRC alone group was 5.71±9.76 ng/mL;the average serum CA125 levels were 43.47±83.52 U/mL respectively.and 13.5±19.68 U/mL;the average serum CA19-9 levels were 184.46±473.13 U/mL and 26.55±43.96 U/mL respectively.In addition,binary logistic regression analysis showed that CA125 was significant in predicting CRC liver metastasis(P<0.05).ROC curve analysis results showed that the areas under the ROC curves of CEA,CA125 and CA19-9 were 0.607,0.692 and 0.586.CONCLUSION These results suggest that combined detection of these tumor markers may help early detection and intervention of CRC liver metastasis,thereby improving patient prognosis.展开更多
In diagnostic trials, clustered data are obtained when several subunits of the same patient are observed. Within-cluster correlations need to be taken into account when analyzing such clustered data. A nonparametric m...In diagnostic trials, clustered data are obtained when several subunits of the same patient are observed. Within-cluster correlations need to be taken into account when analyzing such clustered data. A nonparametric method has been proposed by Obuchowski (1997) to estimate the Receiver Operating Characteristic curve area (AUC) for such clustered data. However, Obuchowski’s estimator gives equal weight to all pairwise rankings within and between cluster. In this paper, we modify Obuchowski’s estimate by allowing weights for the pairwise rankings vary across clusters. We consider the optimal weights for estimating one AUC as well as two AUCs’ difference. Our results in this paper show that the optimal weights depends on not only the within-patient correlation but also the proportion of patients that have both unaffected and affected units. More importantly, we show that the loss of efficiency using equal weight instead of our optimal weights can be severe when there is a large within-cluster correlation and the proportion of patients that have both unaffected and affected units is small.展开更多
Aim:To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods:The accuracy of the spectrophotometric application of the resazurm reduction assay was assessed u...Aim:To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods:The accuracy of the spectrophotometric application of the resazurm reduction assay was assessed using receiver operating characteristic(ROC)analysis.Results:Areas under ROC curves(AUC)for motile sperm concen- tration and sperm index(SI)(sperm concentration multiplied by the square root of percentage sperm motility multi- plied by the percentage normal sperm morphology)were 0.922.The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A_(610)=0.209,where high sensitivity(94.1%)and specificity(91.7%)were calculated.The assay was less accurate when motile sperm concentration was used as the criterion value,vielding sensitivity of 88.2% and specificity of 87.5%,respectively,Likelihood ratios(LR)indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI,whereas in the case of motile sperm concentration,the LR was calculated to be 7.06.Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.展开更多
Objective:The aim of this study was evaluate the diagnostic value of computed tomography(CT) perfusion in breast cancer by the method of receiver operator characteristic curve(ROC) analysis.Methods:Eighty-one cases wi...Objective:The aim of this study was evaluate the diagnostic value of computed tomography(CT) perfusion in breast cancer by the method of receiver operator characteristic curve(ROC) analysis.Methods:Eighty-one cases with breast masses found by health examination or mammography were scanned by multi-slice spiral CT(MSCT) perfusion and hemodynamic parameters of blood flow(BF), mean transit time(MTT) and blood volume(BV) were calculated by deconvolution arithmetic.According to the pathologic results, two groups, benign and malignant were classified and statistical analysis were performed between them.The ROC characteristics of BF, MTT, BV were compared for each and the diagnostic value of the hemodynamic parameters were confirmed.Results:In the malignant group, BF was(0.735 ± 0.440) mL/min/mL, MTT was(22.771 ± 7.647) s and BV was 0.234 ± 0.082.In the benign group, BF was(0.466 ± 0.527) mL/min/mL, MTT was(26.712 ± 12.934) s and BV was 0.179 ± 0.117.There was a significant difference for BF and BV between the benign and malignant groups.When the hemodynamic parameters were used to discriminate the breast lesions, the area under the ROC curve(AUCROC) of BF was 0.832 ± 0.086, the maximum, while AUCROC of BV was 0.695 ± 0.092.There was no significant statistical difference between BF and BV.AUCROC of MTT was 0.473 ± 0.102, which was minimal.Since the threshold of BF was 0.381 mL/min/mL, the sensitivity was 82.3%, the specificity was 73.2%, the positive likelihood ratio(LR) was 3.071 and the negative LR was 0.242.The threshold of BV was 0.190 with sensitivity 73.3%, specificity 56.5%, positive likelihood ratio 1.685 and negative LR 0.473.Conclusion:BF and BV among CT hemodynamic parameters have certain diagnostic value in breast cancer, but BF or BV can not yet be single index to confirm or deny the diagnosis.展开更多
Flash floods are one of the most dangerous natural disasters,especially in hilly terrain,causing loss of life,property,and infrastructures and sudden disruption of traffic.These types of floods are mostly associated w...Flash floods are one of the most dangerous natural disasters,especially in hilly terrain,causing loss of life,property,and infrastructures and sudden disruption of traffic.These types of floods are mostly associated with landslides and erosion of roads within a short time.Most of Vietnamis hilly and mountainous;thus,the problem due to flash flood is severe and requires systematic studies to correctly identify flood susceptible areas for proper landuse planning and traffic management.In this study,three Machine Learning(ML)methods namely Deep Learning Neural Network(DL),Correlation-based FeatureWeighted Naive Bayes(CFWNB),and Adaboost(AB-CFWNB)were used for the development of flash flood susceptibility maps for hilly road section(115 km length)of National Highway(NH)-6 inHoa Binh province,Vietnam.In the proposedmodels,88 past flash flood events were used together with 14 flash floods affecting topographical and geo-environmental factors.The performance of themodels was evaluated using standard statisticalmeasures including Receiver Operating Characteristic(ROC)Curve,Area Under Curve(AUC)and Root Mean Square Error(RMSE).The results revealed that all the models performed well(AUC>0.80)in predicting flash flood susceptibility zones,but the performance of the DL model is the best(AUC:0.972,RMSE:0.352).Therefore,the DL model can be applied to develop an accurate flash flood susceptibility map of hilly terrain which can be used for proper planning and designing of the highways and other infrastructure facilities besides landuse management of the area.展开更多
Objective: To assess the value of MR spectroscopy (MRS) in the diagnosis of prostate cancer by meta-analysis. Methods: Prospective studies were selected from the MEDLINE, Ovid, Embase databases, Springer, Elsevier...Objective: To assess the value of MR spectroscopy (MRS) in the diagnosis of prostate cancer by meta-analysis. Methods: Prospective studies were selected from the MEDLINE, Ovid, Embase databases, Springer, Elsevier, China National Knowledge Infrastructure. According to the suggestion, results were determined by the ratio of (Cho+Cr)/Cit. If this ratio was less than 0.75, negative result was respectively determined, and the definitive tumor was diagnosed as this threshold. According to the assessment standard of Evidence-based Medicine, English and Chinese literature in Grade A and B on MRS imaging was included. According to homogeneity test, different effect models were chosen to calculate different pooled weighted values of sensitivity, specificity and the corresponding 95% confidence intervals (95% CI). Summary receiver operating characteristic (SROC) curves were used to assess the results. Funnel plot was used to analyze publication bias. Results: According to the assessment standard of Evidence-based Medicine, only 5 papers in Grade B were included in this research. The pooled weighted sensitivity and its 95% confidence interval is 82% (73%, 89%) and the pooled weighted sensitivity and its 95% confidence interval is 68% (58%, 76%). The AUC (area under curve) is 83.40%. An asymmetric funnel plot suggested two missing studies leading to publication bias. Conclusion: If the ratio of (Cho+Cr)/Cit is regarded as the diagnostic criteria in detecting prostate cancer by MRS, meta-analysis suggests this method has a better diagnostic value to detect the malignant prostate mass but the sensitivity needs to be improved. We hope to support a method and requirement about diagnostic test. Performing perspective register and improving quality of study design is the only way to reduce the bias and get real information of disease.展开更多
This paper presents a novel bootstrap based method for Receiver Operating Characteristic (ROC) analysis of Fisher classifier. By defining Fisher classifier’s output as a statistic, the bootstrap technique is used to ...This paper presents a novel bootstrap based method for Receiver Operating Characteristic (ROC) analysis of Fisher classifier. By defining Fisher classifier’s output as a statistic, the bootstrap technique is used to obtain the sampling distributions of the outputs for the positive class and the negative class respectively. As a result, the ROC curve is a plot of all the (False Positive Rate (FPR), True Positive Rate (TPR)) pairs by varying the decision threshold over the whole range of the boot- strap sampling distributions. The advantage of this method is, the bootstrap based ROC curves are much stable than those of the holdout or cross-validation, indicating a more stable ROC analysis of Fisher classifier. Experiments on five data sets publicly available demonstrate the effectiveness of the proposed method.展开更多
Background: Consensus on the most reliable assays to detect invasive aspergillosis from minimally or noninvasive samples has not been reached. In this study, we compared the efficacy of an enzyme-linked immunosorbent ...Background: Consensus on the most reliable assays to detect invasive aspergillosis from minimally or noninvasive samples has not been reached. In this study, we compared the efficacy of an enzyme-linked immunosorbent assay (ELISA) for galactomannan (GM) detection and quantitative real-time PCR assay (qRT-PCR) for the diagnosis of invasive pulmonary aspergillosis in a rat model. Methods: Neutropenic, male Sprague-Dawley rats (specific pathogen free;8 weeks old;weight, 200 ± 20 g) were immunosuppressed with cyclophosphamide and infected with Aspergillus fumigatus intratracheally. Tissue and whole blood samples were harvested on days 1, 3, 5, and 7 post-infection and examined with GM ELISA and qRT-PCR. Results: On day 7, A. fumigatus DNA was amplified from 14 of 48 whole blood samples from immunosuppressed infected rats: day 1 (0/12), day 3 (0/12), day 5 (6/12), day 7 (8/12) post infection. The sensitivity and specificity of the qRT-PCR assay were 29.2% and 100%, respectively. Receiver operating characteristic curve (ROC) analysis indicated a Ct cut-off value of 15.35, and the area under the curve (AUC) was 0.627. The GM assay detected antigen in sera obtained on day 1 (5/12), day 3 (9/12), day 5 (12/12), and day 7 (12/12) post-infection, and thus had a sensitivity of 79.2% and a specificity of 100%. The ROC of the GM assay indicated that the optimal cut-off value was 1.40 (specificity, 100%;AUC, 0.919). Conclusions: The GM assay was more sensitive than qRT-PCR assay in diagnosing invasive pulmonary aspergillosis in rats.展开更多
文摘Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR were assessed in 690 Chinese adults (305 men and 385 women) and compared with magnetic resonance imaging (MRI) measurements of abdominal visceral adipose tissue (VA). Receiver operating characteristic (ROC) curves were generated and used to determine the threshold point for each anthropometric parameter. Results 1) MRI showed that 61.7% of overweight/obese individuals (BMI≥25 kg/m2) and 14.2% of normal weight (BMI<25 kg/m2) individuals had abdominal visceral obesity (VA≥100 cm2). 2) VA was positively correlated with each anthropometric variable, of which WC showed the highest correlation (r=0.73-0.77, P<0.001). 3) The best cut-off points for assessing abdominal visceral obesity were as followed: BMI of 26 kg/m2, WC of 90 cm, and WHR of 0.93, with WC being the most sensitive and specific factor. 4) Among subjects with BMI≥28 kg/m2 or WC≥95 cm, 95% of men and 90% of women appeared to have abdominal visceral obesity. Conclusion Measurements of BMI, WC, and WHR can be used in the prediction of abdominal visceral obesity, of which WC was the one with better accuracy.
文摘Objective: To determine the endemic values of cutaneous leishmaniasis in different cities of Fars province, Iran. Methods: Totally, 29 201 cases registered from 2010 to 2015 in Iranian Fars province were selected, and the endemic values of cutaneous leishmaniasis were determined by retrospective clusters derived from spatiotemporal permutation modeling on a time-series design. The accuracy of the values was assessed using receiver operating characteristic(ROC) curve. SPSS version 22, Arc GIS, and ITSM 2002 software tools were used for analysis. Results: Nine statistically significant retrospective clusters(P<0.05) resulted in finding seven significant and accurate endemic values(P<0.1). These valid endemic scores were generalized to the other 18 cities based on 6 different climates in the province. Conclusions: Retrospectively detected clusters with the help of ROC curve analysis could help determine cutaneous leishmaniasis endemic values which are essential for future prediction and prevention policies in the area.
文摘Aim: To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods: The accuracy of the spectrophotometric application of the resazurin reduction assay was assessed using receiver operating characteristic (ROC) analysis. Results: Areas under ROC curves (AUC) for motile sperm concentration and sperm index (SI) (sperm concentration multiplied by the square root of percentage sperm motility multiplied by the percentage normal sperm morphology) were 0.922. The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A610 = 0.209, where high sensitivity (94.1%) and specificity (91.7%) were calculated. The assay was less accurate when motile sperm concentration was used as the criterion value, yielding sensitivity of 88.2% and specificity of 87.5%, respectively. Likelihood ratios (LR) indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI, whereas in the case of motile sperm concentration, the LR was calculated to be 7.06. Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.
文摘Objective(s): Laryngeal inflammations lead to voice disorders. Medical conditions such as chronic laryngitis, gastroesophageal reflux, laryngopharyngeal reflux, Reinke edema and/or vocal folds hemorrhage, result in diverse symptoms including chronic cough, throat cleaning and dysphonia (e.g. hoarseness). In turn, the dysphonic symptoms can be evaluated via subjective and objective procedures. The objective procedures usually include self-perceived questionnaires like the Voice Handicap Index (VHI). Studies reported that VHI can distinguish objectively dysphonic and non-dysphonic populations using the cut-off points of Receiver Operating Characteristic Curves. The purpose of this study was to calculate the cut-off points for individuals exhibiting voice symptoms which had been developed from laryngeal inflammatory diseases in Greece. Methods: One hundred and twelve participants (90 non-dysphonic and 22 dysphonic) filled in the Hellenic Voice Handicap Index (VHI) and the Greek translated version of Voice Evaluation Template (VEF) were administrated. All subjects were evaluated by an Otolaryngologist and a Speech-Language Pathologist. Results: The group with voice disorders exhibited higher VHI scores (in total and in its 3 subdomains) compared to non-dysphonic subgroup. Statistical significant differences were found for all VHI’s total cut-off point of 19.50 (sensitivity: 0.882, 1-specificity: 0.011) and for its three subdomains [functional 6.50 (sensitivity = 0.636, and 1-specificity = 0.022);physical 9.50 (sensitivity = 0.636, and 1-specificity = 0.000);emotional 6.50 (sensitivity = 0.455, and 1-specificity = 0.133)]. Conclusion: The preliminary results showed that VHI could discriminate individuals having voice disorders from laryngeal inflammations. The Voice Handicap Index can be used as a primary health care tool and a self-monitoring procedure in acute and sub-acute phases of the laryngeal inflammation.
基金the financial support provided by the Biotechnology Information Service–Sub-Distributed Information Centre(supported by the Department of Biotechnology,Government of India)Advanced Bioinformatics Centre(supported by the Government of Rajasthan)at Birla Institute of Scientific Research for the infrastructure and facilities for conducting statistical work
文摘Objective: To determine the clinical serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), individually and in combination, for the diagnosis of 50 healthy subjects and 150 cases of esophageal, gastric, and colon cancers. Methods: The sensitivities of the two markers were compared individually and in combination, with specificity set at 100%. Receiver operating characteristic (ROC) curves were plotted. Results: Serum CEA levels were significantly higher in cancer patients than in the control group. The sensitivity of CEA was determined: in esophageal cancer, sensitivity=28%, negative predictive value (NPV)=61.72%, and AUC=0.742 (SE=0.05), with a significance level of P〈0.0001; in gastric cancer, sensitivity=30%, NPV=58.82%, and AUC=0.734 (SE=0.0S), with a significance level of P〈0.0001; in colon cancer, sensitivity=74%, NPV=79.36%, and AUC=0.856 (SE=0.04), with a significance level of P〈0.0001. The sensitivity of CA19-9 was also evaluated: in esophageal cancer, sensitivity=18%, NPV=54.94%, and AUC=0.573 (SE=0.05), with a significance level of P=0.2054. In gastric cancer, sensitivity=42%, NPV=63.29%, and AUC=0.679 (SE=0.05), with a significance level of P〈0.0011. In colon cancer, sensitivity=26%, NPV=57.47%, and AUC=0.S80 (SE=0.05), with a significance level ofP=0.1670. The following were the sensitivities of CEA/CA19-9 combined: in esophageal cancer, sensitivity=42%, NPV=63.29%, SE=0.078 (95% CI: 0.0159-0.322); gastric cancer, sensitivity=S8%, NPV=70.42%, SE=0.072 (9$% CI: -0.0866-0.198); and colon cancer, sensitivity=72%, NPV=78.12%, SE=0.070 (9S% CI: 0.137-0.415). Conclusion: CEA exhibited the highest sensitivity for colon cancer, and CA19-9 exhibited the highest sensitivity for gastric cancer. Combined analysis indicated an increase in diagnostic sensitivity in esophageal and gastric cancer compared with that in colon cancer.
文摘BACKGROUND Colorectal cancer(CRC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many patients.The early detection and diagnosis of CRC are crucial for improving treatment success and patient survival rates.Recently,imaging techniques have been hypothesized to be essential in managing CRC,with magnetic resonance imaging(MRI)and spiral computed tomography(SCT)playing a significant role in enhancing diagnostic and treatment approaches.AIM To explore the effectiveness of MRI and SCT in the preoperative staging of CRC and the prognosis of laparoscopic treatment.METHODS Ninety-five individuals admitted to Zhongshan Hospital Xiamen University underwent MRI and SCT and were diagnosed with CRC.The precision of MRI and SCT for the presurgical classification of CRC was assessed,and pathological staging was used as a reference.Receiver operating characteristic curves were used to evaluate the diagnostic efficacy of blood volume,blood flow,time to peak,permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction on the prognosis of patients with CRC.RESULTS Pathological biopsies confirmed the following CRC stages:23,23,32,and 17 at T1,T2,T3,and T4,respectively.There were 39 cases at the N0 stage,22 at N1,34 at N2,44 at M0 stage,and 51 at M1.Using pathological findings as the benchmark,the combined use of MRI and SCT for preoperative TNM staging in patients with CRC demonstrated superior sensitivity,specificity,and accuracy compared with either modality alone,with a statistically significant difference in accuracy(P<0.05).Receiver operating characteristic curve analysis revealed the predictive values for laparoscopic treatment prognosis,as indicated by the areas under the curve for blood volume,blood flow,time to peak,and permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction were 0.750,0.683,0.772,0.761,0.709,0.719,and 0.910,respectively.The corresponding sensitivity and specificity values were also obtained(P<0.05).CONCLUSION MRI with SCT is effective in the clinical diagnosis of patients with CRC and is worthy of clinical promotion.
文摘BACKGROUND Hepatic metastases are common and difficult to treat after colorectal cancer(CRC)surgery.The predictive value of carcinoembryonic antigen(CEA),cancer antigen(CA)125 and CA19-9 combined tests for liver metastasis is unclear.AIM To evaluate predictive value of combined tests for CEA,CA125,and CA19-9 levels in patients with liver metastases of CRC.METHODS The retrospective study included patients with CRC alone(50 cases)and patients with CRC combined with liver metastases(50 cases)who were hospitalized between January 2021 and January 2023.Serum CEA,CA125 and CA19-9 levels were compared between the two groups,and binary logistic regression was used to analyze the predictive value of the combination of these tumor markers in liver metastasis.In addition,we performed receiver operating characteristic(ROC)curve analysis to assess its diagnostic accuracy.RESULTS The results showed that the serum CEA,CA125 and CA19-9 levels in the CRC with liver metastasis group were significantly higher than those in the CRC alone group.Specifically,the average serum CEA level in the CRC with liver metastasis group was 162.03±810.01 ng/mL,while that in the CRC alone group was 5.71±9.76 ng/mL;the average serum CA125 levels were 43.47±83.52 U/mL respectively.and 13.5±19.68 U/mL;the average serum CA19-9 levels were 184.46±473.13 U/mL and 26.55±43.96 U/mL respectively.In addition,binary logistic regression analysis showed that CA125 was significant in predicting CRC liver metastasis(P<0.05).ROC curve analysis results showed that the areas under the ROC curves of CEA,CA125 and CA19-9 were 0.607,0.692 and 0.586.CONCLUSION These results suggest that combined detection of these tumor markers may help early detection and intervention of CRC liver metastasis,thereby improving patient prognosis.
文摘In diagnostic trials, clustered data are obtained when several subunits of the same patient are observed. Within-cluster correlations need to be taken into account when analyzing such clustered data. A nonparametric method has been proposed by Obuchowski (1997) to estimate the Receiver Operating Characteristic curve area (AUC) for such clustered data. However, Obuchowski’s estimator gives equal weight to all pairwise rankings within and between cluster. In this paper, we modify Obuchowski’s estimate by allowing weights for the pairwise rankings vary across clusters. We consider the optimal weights for estimating one AUC as well as two AUCs’ difference. Our results in this paper show that the optimal weights depends on not only the within-patient correlation but also the proportion of patients that have both unaffected and affected units. More importantly, we show that the loss of efficiency using equal weight instead of our optimal weights can be severe when there is a large within-cluster correlation and the proportion of patients that have both unaffected and affected units is small.
文摘Aim:To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods:The accuracy of the spectrophotometric application of the resazurm reduction assay was assessed using receiver operating characteristic(ROC)analysis.Results:Areas under ROC curves(AUC)for motile sperm concen- tration and sperm index(SI)(sperm concentration multiplied by the square root of percentage sperm motility multi- plied by the percentage normal sperm morphology)were 0.922.The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A_(610)=0.209,where high sensitivity(94.1%)and specificity(91.7%)were calculated.The assay was less accurate when motile sperm concentration was used as the criterion value,vielding sensitivity of 88.2% and specificity of 87.5%,respectively,Likelihood ratios(LR)indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI,whereas in the case of motile sperm concentration,the LR was calculated to be 7.06.Conclusion: These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.
文摘Objective:The aim of this study was evaluate the diagnostic value of computed tomography(CT) perfusion in breast cancer by the method of receiver operator characteristic curve(ROC) analysis.Methods:Eighty-one cases with breast masses found by health examination or mammography were scanned by multi-slice spiral CT(MSCT) perfusion and hemodynamic parameters of blood flow(BF), mean transit time(MTT) and blood volume(BV) were calculated by deconvolution arithmetic.According to the pathologic results, two groups, benign and malignant were classified and statistical analysis were performed between them.The ROC characteristics of BF, MTT, BV were compared for each and the diagnostic value of the hemodynamic parameters were confirmed.Results:In the malignant group, BF was(0.735 ± 0.440) mL/min/mL, MTT was(22.771 ± 7.647) s and BV was 0.234 ± 0.082.In the benign group, BF was(0.466 ± 0.527) mL/min/mL, MTT was(26.712 ± 12.934) s and BV was 0.179 ± 0.117.There was a significant difference for BF and BV between the benign and malignant groups.When the hemodynamic parameters were used to discriminate the breast lesions, the area under the ROC curve(AUCROC) of BF was 0.832 ± 0.086, the maximum, while AUCROC of BV was 0.695 ± 0.092.There was no significant statistical difference between BF and BV.AUCROC of MTT was 0.473 ± 0.102, which was minimal.Since the threshold of BF was 0.381 mL/min/mL, the sensitivity was 82.3%, the specificity was 73.2%, the positive likelihood ratio(LR) was 3.071 and the negative LR was 0.242.The threshold of BV was 0.190 with sensitivity 73.3%, specificity 56.5%, positive likelihood ratio 1.685 and negative LR 0.473.Conclusion:BF and BV among CT hemodynamic parameters have certain diagnostic value in breast cancer, but BF or BV can not yet be single index to confirm or deny the diagnosis.
基金funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED)under Grant No.105.08-2019.03.
文摘Flash floods are one of the most dangerous natural disasters,especially in hilly terrain,causing loss of life,property,and infrastructures and sudden disruption of traffic.These types of floods are mostly associated with landslides and erosion of roads within a short time.Most of Vietnamis hilly and mountainous;thus,the problem due to flash flood is severe and requires systematic studies to correctly identify flood susceptible areas for proper landuse planning and traffic management.In this study,three Machine Learning(ML)methods namely Deep Learning Neural Network(DL),Correlation-based FeatureWeighted Naive Bayes(CFWNB),and Adaboost(AB-CFWNB)were used for the development of flash flood susceptibility maps for hilly road section(115 km length)of National Highway(NH)-6 inHoa Binh province,Vietnam.In the proposedmodels,88 past flash flood events were used together with 14 flash floods affecting topographical and geo-environmental factors.The performance of themodels was evaluated using standard statisticalmeasures including Receiver Operating Characteristic(ROC)Curve,Area Under Curve(AUC)and Root Mean Square Error(RMSE).The results revealed that all the models performed well(AUC>0.80)in predicting flash flood susceptibility zones,but the performance of the DL model is the best(AUC:0.972,RMSE:0.352).Therefore,the DL model can be applied to develop an accurate flash flood susceptibility map of hilly terrain which can be used for proper planning and designing of the highways and other infrastructure facilities besides landuse management of the area.
文摘Objective: To assess the value of MR spectroscopy (MRS) in the diagnosis of prostate cancer by meta-analysis. Methods: Prospective studies were selected from the MEDLINE, Ovid, Embase databases, Springer, Elsevier, China National Knowledge Infrastructure. According to the suggestion, results were determined by the ratio of (Cho+Cr)/Cit. If this ratio was less than 0.75, negative result was respectively determined, and the definitive tumor was diagnosed as this threshold. According to the assessment standard of Evidence-based Medicine, English and Chinese literature in Grade A and B on MRS imaging was included. According to homogeneity test, different effect models were chosen to calculate different pooled weighted values of sensitivity, specificity and the corresponding 95% confidence intervals (95% CI). Summary receiver operating characteristic (SROC) curves were used to assess the results. Funnel plot was used to analyze publication bias. Results: According to the assessment standard of Evidence-based Medicine, only 5 papers in Grade B were included in this research. The pooled weighted sensitivity and its 95% confidence interval is 82% (73%, 89%) and the pooled weighted sensitivity and its 95% confidence interval is 68% (58%, 76%). The AUC (area under curve) is 83.40%. An asymmetric funnel plot suggested two missing studies leading to publication bias. Conclusion: If the ratio of (Cho+Cr)/Cit is regarded as the diagnostic criteria in detecting prostate cancer by MRS, meta-analysis suggests this method has a better diagnostic value to detect the malignant prostate mass but the sensitivity needs to be improved. We hope to support a method and requirement about diagnostic test. Performing perspective register and improving quality of study design is the only way to reduce the bias and get real information of disease.
基金the Natural Science Foundation of Zhejiang Province of China (No. Y104540)the Foundation of the Key Laboratory of Advanced Information Science and Network Technology of Beijing, China (No.TDXX0509).
文摘This paper presents a novel bootstrap based method for Receiver Operating Characteristic (ROC) analysis of Fisher classifier. By defining Fisher classifier’s output as a statistic, the bootstrap technique is used to obtain the sampling distributions of the outputs for the positive class and the negative class respectively. As a result, the ROC curve is a plot of all the (False Positive Rate (FPR), True Positive Rate (TPR)) pairs by varying the decision threshold over the whole range of the boot- strap sampling distributions. The advantage of this method is, the bootstrap based ROC curves are much stable than those of the holdout or cross-validation, indicating a more stable ROC analysis of Fisher classifier. Experiments on five data sets publicly available demonstrate the effectiveness of the proposed method.
文摘Background: Consensus on the most reliable assays to detect invasive aspergillosis from minimally or noninvasive samples has not been reached. In this study, we compared the efficacy of an enzyme-linked immunosorbent assay (ELISA) for galactomannan (GM) detection and quantitative real-time PCR assay (qRT-PCR) for the diagnosis of invasive pulmonary aspergillosis in a rat model. Methods: Neutropenic, male Sprague-Dawley rats (specific pathogen free;8 weeks old;weight, 200 ± 20 g) were immunosuppressed with cyclophosphamide and infected with Aspergillus fumigatus intratracheally. Tissue and whole blood samples were harvested on days 1, 3, 5, and 7 post-infection and examined with GM ELISA and qRT-PCR. Results: On day 7, A. fumigatus DNA was amplified from 14 of 48 whole blood samples from immunosuppressed infected rats: day 1 (0/12), day 3 (0/12), day 5 (6/12), day 7 (8/12) post infection. The sensitivity and specificity of the qRT-PCR assay were 29.2% and 100%, respectively. Receiver operating characteristic curve (ROC) analysis indicated a Ct cut-off value of 15.35, and the area under the curve (AUC) was 0.627. The GM assay detected antigen in sera obtained on day 1 (5/12), day 3 (9/12), day 5 (12/12), and day 7 (12/12) post-infection, and thus had a sensitivity of 79.2% and a specificity of 100%. The ROC of the GM assay indicated that the optimal cut-off value was 1.40 (specificity, 100%;AUC, 0.919). Conclusions: The GM assay was more sensitive than qRT-PCR assay in diagnosing invasive pulmonary aspergillosis in rats.
文摘目的探讨肾小管及肾小球相关标志物在2型糖尿病(type 2 diabetes mellitus,T2DM)患者不同肾损伤阶段的诊断价值。方法选取于2018年4月1日至2019年10月31日入住首都医科大学附属北京同仁医院内分泌科的T2DM患者272例,完善临床生化指标及尿蛋白四项:尿微量白蛋白/肌酐(urinary albumin to creatinine ratio,ACR)、α1-微球蛋白/肌酐(urinary α1-microglobulin to creatinine ratio,UA1CR)、免疫球蛋白G/肌酐(urinary immunoglobulin G to creatinine ratio,UIGG)、转铁蛋白/肌酐(urinary transferrin to creatinine ratio,UTRF);进行眼底照相、核医学99mTc-EC检测肾有效血浆流量(effective renal plasma flow,ERPF)和99mTc-DTPA检测肾小球滤过率(glomerular filtration rate,GFR)。根据ACR和眼底检查结果分为4组:正常蛋白尿无糖尿病视网膜病变(diabetic retinopathy,DR)132例,即对照组(ACR≤30 mg/g);正常蛋白尿合并DR 32例,为糖尿病肾病(diabetic kidney disease,DKD)前期组;微量蛋白尿组78例(30<ACR≤300 mg/g)和大量蛋白尿组30例(ACR>300 mg/g)。比较四组间尿蛋白四项和ERPF、GFR的水平,通过受试者工作特征(receiver operating characteristic,ROC)曲线评价上述各指标在不同肾损伤阶段的诊断价值。结果尿蛋白四项和ERPF、GFR的水平在不同组间差异有统计学意义(P<0.05)。在尿蛋白正常组中,DR组中肾小管功能标志物UA1CR较对照组明显升高(P<0.01);肾小球功能标志物ACR、UTRF和GFR在两组间差异无统计学意义(P>0.05),DR组UIGG较对照组升高(P<0.01)。在微量蛋白尿组和大量蛋白尿组,尿蛋白四项随肾损伤程度增加而增加,而ERPF和GFR随肾损伤程度增加而降低。ROC曲线分析显示,在尿蛋白排出正常的T2DM患者中合并DR组中肾小管功能标志物UA1CR和ERPF的曲线下面积(area under the curve,AUC)分别为68.2%(P<0.01)和60.5%(P<0.05),而肾小球功能标志物ACR和GFR的AUC均小于60%,差异无统计学意义(P>0.05)。尿蛋白四项及GFR在微量和大量蛋白尿组的AUC均大于60%(P<0.05),ERPF在大量蛋白尿组AUC为67.2%(P<0.05)。结论T2DM极早期微血管改变即ACR正常仅有DR时,肾小管标志物UA1CR先于肾小球标志物ACR和GFR发生变化。肾损伤早期,肾小管标志物诊断效能优于肾小球;肾损伤后期,肾小球标志物诊断效能优于肾小管。提示DKD肾小管功能的改变可能早于肾小球。