scholarly journals An Comprehensive Index (CIB) with Combination of Consistency in both Case Control and Cohort Study to Determine the Efficacy of a Biomarker

2020 ◽  
Author(s):  
Liu Hui
Keyword(s):  
Cohort Study ◽  
Roc Analysis ◽  
Geometric Mean ◽  
Simulated Data ◽  
Case Control ◽  
Youden Index ◽  
Comprehensive Index ◽  
The Common ◽  
Sensitivity Specificity ◽  
Consistency Rate

Abstract Background: This study aimed to describe biomarkers using the comprehensive index of biomarker (CIB) based on consistency rate in both case control (Youden index, Yen) and cohort study (Crc) to determine the efficacy of a biomarker. Methods: The CIB is the geometric mean of Yen and Crc. The simulated data were generated to observe CIB features of sensitivity, specificity, and receiver operating characteristic (ROC) analysis for biomarkersResults: CIB was found to be related to the CRC values ROC analysis. The higher Spe could indicate better diagnostic power and the higher Sen could indicate better joint action for biomarkers with the same Yen. Although Yen is the common index used to evaluate the effectiveness of a biomarker, unfortunately, the Yen value was significantly larger than CIB value under the moderate Spe, showing overestimation.Conclusion: The CIB with combination of consistency in both case control and cohort study could be more reasonable. The CIB could provide a better understanding of the power of a biomarker and would be better at evaluating biomarkers from new systems or concepts.

scholarly journals Structural Imaging-Based Biomarkers for Detecting Craving and Predicting Relapse in Subjects With Methamphetamine Dependence

2021 ◽  
Vol 11 ◽  
Author(s):  
Chang Qi ◽  
Xiaobing Fan ◽  
Sean Foxley ◽  
Qiuxia Wu ◽  
Jinsong Tang ◽  
...  
Keyword(s):  
Roc Analysis ◽  
Gray Matter Volume ◽  
Objective Measure ◽  
Region Of Interest ◽  
Structural Mri ◽  
Youden Index ◽  
Model Group ◽  
Methamphetamine Dependence ◽  
Sensitivity Specificity

Background: Craving is the predictor of relapse, and insula cortex (IC) is a critical neural substrate for craving and drug seeking. This study investigated whether IC abnormalities among MA users can detect craving state and predict relapse susceptibility.Methods: A total of 142 subjects with a history of MA dependence completed structural MRI (sMRI) scans, and 30 subjects (10 subjects relapsed) completed 4-month follow-up scans. MA craving was measured by the Visual Analog Scale for Craving. Abnormalities of IC gray matter volume (GMV) between the subjects with and without craving were investigated by voxel-based morphometry (VBM). The receiver operating characteristic (ROC) analysis was performed for the region-of-interest (ROI) of IC GMV to assess the diagnostic accuracy.Results: By comparing whole-brain volume maps, this study found that subjects without craving (n = 64) had a significantly extensive decrease in IC GMV (family-wise error correction, p < 0.05) than subjects with craving group (n = 78). The ROI of IC GMV had a significantly positive correlation with the craving scores reported by MA users. The ROC analysis showed a good discrimination (area under curve is 0.82/0.80 left/right) for IC GMV between the subjects with and without craving. By selecting Youden index cut-off point from whole model group, calculated sensitivity/specificity was equal to 78/70% and 70/75% for left and right IC, respectively. By applying the above optimal cut-off values to 30 follow-up subjects as validations, the results showed a similar sensitivity (73–80%) and specificity (73–80%) for detecting craving state as model group. For predicting relapse susceptibility, the sensitivity (50–55%) was low and the specificity (80–90%) was high.Conclusions: Our study provides the first evidence that sMRI may be used to diagnosis the craving state in MA users based on optimal cut-off values, which could be served as MRI bio-markers and an objective measure of craving state.

scholarly journals Need for discriminating between diagnostic and screening efficacy to estimate a biomarker based on case control and cohort studies

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Liu Hui
Keyword(s):  
Cohort Studies ◽  
High Probability ◽  
Case Control ◽  
Youden Index ◽  
Diagnostic Screening ◽  
Significant Difference ◽  
The Common ◽  
The Mean ◽  
Low Probability ◽  
Common Index

AbstractThis study proposes the comprehensive index of biomarker (CIB), based on the consistency of a biomarker in case control (Youden index, J) and cohort studies (Crc), to evaluate biomarker efficacy. CIB was calculated as the mean of J and Crc. Analysis of the effect of sensitivity and specificity on CIB and ROC analysis of CIB were performed in simulated and actual datasets. J and CIB had similar values for high-probability events (say probability was 0.50), but there was a significant difference between J and CIB for low-probability events (say probability was 0.05). Therefore, as the subjects considered for diagnosis are usually symptomatic, the occurrence of a disease can be assumed to be a high-probability event. In contrast, as the subjects considered in screening for a disease are usually healthy and asymptomatic, the occurrence of a disease is assumed to be a low-probability event. Although J is the common index used to evaluate the diagnostic effectiveness, unfortunately, the J value is significantly larger than CIB value in a low-probability event, showing overestimation for screening purpose. CIB could have more potential than J for determining the screening efficacy of a biomarker. The efficacy of a biomarker could differ for diagnostic, screening, predictive, and prognostic purposes, and it would be better to evaluate the efficacy of biomarkers for specific systems or contexts.

scholarly journals Efficiency of non-invasive prenatal screening in pregnant women at advanced maternal age

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Hui Zhu ◽  
Xiaoxiao Jin ◽  
Yuqing Xu ◽  
Weihua Zhang ◽  
Xiaodan Liu ◽  
...  
Keyword(s):  
High Risk ◽  
Pregnant Women ◽  
Predictive Value ◽  
Trisomy 21 ◽  
Maternal Age ◽  
Prenatal Screening ◽  
Advanced Maternal Age ◽  
Youden Index ◽  
Non Invasive ◽  
Sensitivity Specificity

Abstract Background Non-invasive prenatal screening (NIPS) is widely used as the alternative choice for pregnant women at high-risk of fetal aneuploidy. However, whether NIPS has a good detective efficiency for pregnant women at advanced maternal age (AMA) has not been fully studied especially in Chinese women. Methods Twenty-nine thousand three hundred forty-three pregnant women at AMA with singleton pregnancy who received NIPS and followed-up were recruited. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), receiver operating characteristic (ROC) curves and the Youden Index for detecting fetal chromosomal aneuploidies were analyzed. The relationship between maternal age and common fetal chromosomal aneuploidy was observed. Results The sensitivity, specificity, PPV, NPV of NIPS for detecting fetal trisomy 21 were 99.11, 99.96, 90.98, and 100%, respectively. These same parameters for detecting fetal trisomy 18 were 100, 99.94, 67.92, and 100%, respectively. Finally, these parameters for detecting trisomy 13 were 100, 99.96, 27.78, and 100%, respectively. The prevalence of fetal trisomy 21 increased exponentially with maternal age. The high-risk percentage incidence rate of fetal trisomy 21 was significantly higher in the pregnant women at 37 years old or above than that in pregnant women at 35 to 37 years old. (Youden index = 37). Conclusion It is indicated that NIPS is an effective prenatal screening method for pregnant women at AMA.

scholarly journals The Effect of Prophylactic HPV Vaccines on Oral and Oropharyngeal HPV Infection—A Systematic Review

Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1339
Author(s):  
Kristoffer Juul Nielsen ◽  
Kathrine Kronberg Jakobsen ◽  
Jakob Schmidt Jensen ◽  
Christian Grønhøj ◽  
Christian Von Buchwald
Keyword(s):  
Cohort Study ◽  
Oropharyngeal Cancer ◽  
Hpv Infection ◽  
Case Control ◽  
Igg Antibodies ◽  
Hpv Vaccines ◽  
Case Control Studies ◽  
Cross Sectional ◽  
Post Vaccination ◽  
Cross Sectional Studies

Human papillomavirus (HPV) imposes an increased risk of developing cervical, anal and oropharyngeal cancer. In the Western world, HPV infection is currently the major cause of oropharyngeal cancer. The effectiveness of HPV vaccines for oral or oropharyngeal HPV infection is yet to be determined. This study conducted a systematic literature search in Pubmed and Embase. Studies investigating the impact of HPV vaccines on oral or oropharyngeal HPV infection were enrolled. This review reports the relative prevention percentage (RPP), including a risk of bias assessment as well as a quality assessment study. Nine studies were included (48,777 participants): five cross-sectional studies; one randomized community trial study (RCT); one longitudinal cohort study; and two case-control studies. A significant mean RPP of 83.9% (66.6–97.8%) was calculated from the cross-sectional studies, 82.4% in the included RCT and 83% in the longitudinal cohort study. Further, two case-control studies that measured antibody response in participants immunized with HPV vaccines were included. Respectively, 100% and 93.2% of participants developed HPV-16 Immunoglobulin G (IgG) antibodies in oral fluids post-vaccination. Analysis of the studies identified a significant decrease in vaccine-type oral or oropharyngeal HPV infections in study participants immunized with HPV vaccines across study designs and heterogenous populations. Further, a significant percentage of participants developed IgG antibodies in oral fluid post-vaccination.

Validity of hearTest Smartphone-Based Audiometry for Hearing Screening in Workers Exposed to Noise

2020 ◽  
Author(s):  
Luma Cordeiro Rodrigues ◽  
Silvia Ferrite ◽  
Ana Paula Corona
Keyword(s):  
Hearing Loss ◽  
High Specificity ◽  
Hearing Screening ◽  
Youden Index ◽  
Hearing Level ◽  
Predictive Values ◽  
Auditory Thresholds ◽  
The Mean ◽  
Low Sensitivity ◽  
Sensitivity Specificity

Abstract Purpose This article investigates the validity of a smartphone-based audiometry for hearing screening to identify hearing loss in workers exposed to noise. Research Design This is a validation study comparing hearing screening with the hearTest to conventional audiometry. The study population included all workers who attended the Brazilian Social Service of Industry to undergo periodic examinations. Sensitivity, specificity, the Youden index, and positive (PPV) and negative predictive values (NPV) for hearing screening obtained by the hearTest were estimated according to three definitions of hearing loss: any threshold greater than 25 dB hearing level (HL), the mean auditory thresholds for 0.5, 1, 2, and 4 kHz greater than 25 dB HL, and the mean thresholds for 3, 4, and 6 kHz greater than 25 dB HL. Note that 95% confidence intervals were calculated for all measurements. Results A total of 232 workers participated in the study. Hearing screening with the hearTest presented good sensitivity (93.8%), specificity (83.9%), and Youden index (77.7%) values, a NPV (97.2%), and a low PPV (69.0%) for the identification of hearing loss defined as any auditory threshold greater than 25 dB HL. For the other definitions of hearing loss, we observed high specificity, PPV and NPV, as well as low sensitivity and Youden index. Conclusion The hearTest is an accurate hearing screening tool to identify hearing loss in workers exposed to noise, including those with noise-induced hearing loss, although it does not replace conventional audiometry.

scholarly journals Hyperbolastic Models from a Stochastic Differential Equation Point of View

Mathematics ◽  
2021 ◽  
Vol 9 (16) ◽  
pp. 1835
Author(s):  
Antonio Barrera ◽  
Patricia Román-Román ◽  
Francisco Torres-Ruiz
Keyword(s):  
Differential Equation ◽  
Simulated Data ◽  
Real Data ◽  
Point Of View ◽  
Likelihood Method ◽  
Numerical Resolution ◽  
The Family ◽  
The Common ◽  
Linear Differential ◽  
Mean Function

A joint and unified vision of stochastic diffusion models associated with the family of hyperbolastic curves is presented. The motivation behind this approach stems from the fact that all hyperbolastic curves verify a linear differential equation of the Malthusian type. By virtue of this, and by adding a multiplicative noise to said ordinary differential equation, a diffusion process may be associated with each curve whose mean function is said curve. The inference in the resulting processes is presented jointly, as well as the strategies developed to obtain the initial solutions necessary for the numerical resolution of the system of equations resulting from the application of the maximum likelihood method. The common perspective presented is especially useful for the implementation of the necessary procedures for fitting the models to real data. Some examples based on simulated data support the suitability of the development described in the present paper.

scholarly journals Early Post-Operative Pancreatitis and Systemic Inflammatory Response Assessed by Serum Lipase and IL-6 Predict Pancreatic Fistula

2020 ◽  
Vol 44 (12) ◽  
pp. 4236-4244
Author(s):  
S. Gasteiger ◽  
F. Primavesi ◽  
G. Göbel ◽  
E. Braunwarth ◽  
B. Cardini ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Pancreatic Fistula ◽  
Pancreatic Resection ◽  
Roc Analysis ◽  
Youden Index ◽  
Clinical Trial Registration ◽  
Serum Lipase ◽  
Mortality And Morbidity ◽  
Prospective Pilot Study ◽  
Early Predictor

Abstract Background Post-operative pancreatic fistula (POPF) remains a critical complication after pancreatic resection. This prospective pilot study evaluates perioperative markers of pancreatitis and systemic inflammation to predict clinically relevant grade B/C-POPF (CR-POPF). Methods All patients undergoing pancreatic resection from December 2017 to April 2019 were prospectively enrolled. Surgical procedures and outcomes were correlated with perioperative blood markers. ROC analysis was performed to assess their predictive value for CR-POPF. Cut-offs were calculated with the Youden index. Results In total, 70 patients were analysed (43 pancreatoduodenectomies and 27 distal pancreatectomies). In-hospital/90-d mortality and morbidity were 5.7/7.1% (n = 4/n = 5) and 75.7% (n = 53). Major complications (Clavien–Dindo ≥ 3a) occurred in 28 (40.0%) patients, CR-POPF in 20 (28.6%) patients. Serum lipase (cut-off > 51U/L) and IL-6 (> 56.5 ng/l) on POD3 were significant predictors for CR-POPF (AUC = 0.799, 95%-CI 0.686–0.912 and AUC = 0.784, 95%-CI 0.668–0.900; combined AUC = 0.858, 95%-CI 0.758–0.958; all p < 0.001). Patients with both or one factor(s) above cut-off more frequently developed CR-POPF than cases without (100 vs. 50% vs. 7.5%, p < 0.001). This also applied for overall and severe complications (p = 0.013 and p = 0.009). Conclusions Post-operative pancreatitis and inflammatory response are major determinants for development of POPF. A combination of serum lipase and IL-6 on POD3 is a highly significant early predictor of CR-POPF and overall complications, potentially guiding patient management. Clinical trial registration The study protocol was registered at clinicaltrials.gov (NCT04294797)

scholarly journals Potential role of the lectin pathway of complement in the pathogenesis and disease manifestations of systemic sclerosis: a case-control and cohort study

2014 ◽  
Vol 16 (6) ◽  
Author(s):  
Michael Osthoff ◽  
Gene-Siew Ngian ◽  
Melinda M Dean ◽  
Mandana Nikpour ◽  
Wendy Stevens ◽  
...  
Keyword(s):  
Cohort Study ◽  
Systemic Sclerosis ◽  
Potential Role ◽  
Case Control ◽  
Lectin Pathway
Sign in / Sign up

Export Citation Format

Share Document