Positivity Criterion and Cutoff Values

2012 ◽  
Author(s):  
Mark H. Eckman
Keyword(s):  
Cutoff Values ◽  
Positivity Criterion

Is That Measure Really One-Dimensional?

Methodology ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 188-196 ◽  
Author(s):  
Esther T. Beierl ◽  
Markus Bühner ◽  
Moritz Heene
Keyword(s):  
Model Fit ◽  
Nuisance Parameters ◽  
Factorial Validity ◽  
Fit Indices ◽  
Analysis Model ◽  
Factor Analysis Model ◽  
One Dimensional ◽  
Confirmatory Factor Analysis Model ◽  
Cutoff Values ◽  
Confirmatory Factor

Abstract. Factorial validity is often assessed using confirmatory factor analysis. Model fit is commonly evaluated using the cutoff values for the fit indices proposed by Hu and Bentler (1999) . There is a body of research showing that those cutoff values cannot be generalized. Model fit does not only depend on the severity of misspecification, but also on nuisance parameters, which are independent of the misspecification. Using a simulation study, we demonstrate their influence on measures of model fit. We specified a severe misspecification, omitting a second factor, which signifies factorial invalidity. Measures of model fit showed only small misfit because nuisance parameters, magnitude of factor loadings and a balanced/imbalanced number of indicators per factor, also influenced the degree of misfit. Drawing from our results, we discuss challenges in the assessment of factorial validity.

scholarly journals Clinical evaluation of manual stress testing, stress ultrasound and 3D stress MRI in chronic mechanical ankle instability

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Markus Wenning ◽  
Dominic Gehring ◽  
Thomas Lange ◽  
David Fuerst-Meroth ◽  
Paul Streicher ◽  
...  
Keyword(s):  
Stress Testing ◽  
Ankle Instability ◽  
Tilt Test ◽  
Diagnostic Study ◽  
Mechanical Instability ◽  
Subjective Character ◽  
Balance Test ◽  
Research And Practice ◽  
Cutoff Values ◽  
Patient Reported

Abstract Background Chronic ankle instability (CAI) arises from the two etiological factors of functional (FAI) and mechanical ankle instability (MAI). To distinguish the contributions of the two etiologies, it is necessary to quantitively assess functional and mechanical deficits. Validated and reproducible assessment of mechanical instability remains a challenge in current research and practice. Physical examination, stress sonography and a novel 3D stress MRI have been used, while stress radiography has been called into question and arthrometry is limited to research purposes. The interaction of these primarily mechanical measurements with the functional and subjective components of CAI are subject to debate. The aim of this study was the evaluation of the clinical and biomechanical preferences of the three different methods in the diagnosis of MAI. Methods In this cross-sectional diagnostic study, we compared three different diagnostic approaches to mechanical ankle instability: (1) manual stress testing (anterior drawer test [ADT] and talar tilt test [TTT]), (2) stress sonography and (3) 3D stress MRI (3SAM) The latter includes quantification of 3D cartilage contact area (CCA) in plantarflexion-supination compared to neutral-null position. We applied these measurements to a cohort of patients suffering from chronic mechanical ankle instability (n = 25) to a matched cohort of healthy controls (n = 25). Perceived instability was assessed using the Cumberland Ankle Instability Tool (CAIT) and Forgotten Joint Score (FJS). Functional deficits were measured using postural sway and the y-Balance test. Results Significant differences between the two groups (single-factor “group” ANOVA, p < 0.05) were found in all of the mechanical assessments with strong effect sizes. Spearman’s correlations were strong for CAIT and manual stress testing (TTT rho = − 0.83, ADT rho = − 0.81), 3D stress MRI (rho = − 0.53) and stress sonography (TTT rho = − 0.48, ADT rho = − 0.44). Furthermore, the correlation between manual stress testing and CCA in the fibulotalar articulation (CCAFT) was strong (rho = 0.54) and the correlations to stress sonography were moderate (ADT rho = 0.47 and TTT rho = 0.43). The calculation of cutoff values revealed a distance of > 5.4 mm increase in ligament length during stress sonography (sensitivity 0.92, specificity 0.6) and > 43% loss of articulating surface in the fibulotalar joint (CCAFT in supination-plantarflexion using 3SAM, sensitivity 0.71, specificity 0.8) as potential cutoff values for diagnosing MAI. Conclusions Manual stress testing showed to be a valuable method of identifying mechanical ankle instability. However, due to is subjective character it may overvalue patient-reported instability as a factor which explains the high correlation to the CAIT-score, but this may also reduce its value in diagnosing the isolated mechanical quality of the joint. Thus, there is a persisting need for objective and reproducible alternatives focusing on MAI. According to our results, 3D stress MRI and stress sonography represent valuable alternatives and may be used to quantitively assess mechanical ankle instability in research and practice. Trial registration German Registry of Clinical Trials # DRKS00016356, registered on 05/11/2019.

scholarly journals Impulse oscillometry for detection of small airway dysfunction in subjects with chronic respiratory symptoms and preserved pulmonary function

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Liang-Yuan Li ◽  
Tian-Sheng Yan ◽  
Jing Yang ◽  
Yu-Qi Li ◽  
Lin-Xi Fu ◽  
...  
Keyword(s):  
Pulmonary Function ◽  
Respiratory Symptoms ◽  
Early Stage ◽  
Roc Curves ◽  
Diagnostic Value ◽  
Small Airway ◽  
Impulse Oscillometry ◽  
Additional Method ◽  
Cutoff Values ◽  
Higher Sensitivity

Abstract Background Subjects with chronic respiratory symptoms and preserved pulmonary function (PPF) may have small airway dysfunction (SAD). As the most common means to detect SAD, spirometry needs good cooperation and its reliability is controversial. Impulse oscillometry (IOS) may complete the deficiency of spirometry and have higher sensitivity. We aimed to explore the diagnostic value of IOS to detect SAD in symptomatic subjects with PPF. Methods The evaluation of symptoms, spirometry and IOS results in 209 subjects with chronic respiratory symptoms and PPF were assessed. ROC curves of IOS to detect SAD were analyzed. Results 209 subjects with chronic respiratory symptoms and PPF were included. Subjects who reported sputum had higher R5–R20 and Fres than those who didn’t. Subjects with dyspnea had higher R5, R5–R20 and AX than those without. CAT and mMRC scores correlated better with IOS parameters than with spirometry. R5, R5–R20, AX and Fres in subjects with SAD (n = 42) significantly increased compared to those without. Cutoff values for IOS parameters to detect SAD were 0.30 kPa/L s for R5, 0.015 kPa/L s for R5–R20, 0.30 kPa/L for AX and 11.23 Hz for Fres. Fres has the largest AUC (0.665, P = 0.001) among these parameters. Compared with spirometry, prevalence of SAD was higher when measured with IOS. R5 could detect the most SAD subjects with a prevalence of 60.77% and a sensitivity of 81% (AUC = 0.659, P = 0.002). Conclusion IOS is more sensitive to detect SAD than spirometry in subjects with chronic respiratory symptoms and PPF, and it correlates better with symptoms. IOS could be an additional method for SAD detection in the early stage of diseases.

scholarly journals High-sensitive cardiac troponin for the diagnosis of acute myocardial infarction in different chronic kidney disease stages

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Daijin Ren ◽  
Tianlun Huang ◽  
Xin Liu ◽  
Gaosi Xu
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Chronic Kidney Disease ◽  
Renal Function ◽  
Kidney Disease ◽  
Cardiac Troponin ◽  
Optimal Cutoff ◽  
Cutoff Values ◽  
Optimal Value ◽  
Disease Stages

Abstract Background Chronic kidney disease (CKD) are associated with acute myocardial infarction (AMI). High-sensitive cardiac troponin (hs-cTn) has been evidenced to enhance the early diagnostic accuracy of AMI, but hs-cTn levels are often chronically elevated in CKD patients, which reduces their diagnostic utility. The aim of this study was to derive optimal cutoff-values of hs-cTn levels in patients with CKD and suspected AMI. Methods In this retrospective paper, a total of 3295 patients with chest pain (2758 in AMI group and 537 in Non-AMI group) were recruited, of whom 23.1% were had an estimated glomerular filtration rate (eGFR) of < 60 mL min−1 (1.73 m2)−1. Hs-cTnI values were measured at presentation. Results AMI was diagnosed in 83.7% of all patients. The optimal value of hs-TnI in diagnosing AMI was 1.15 ng mL−1, which were higher in males than females comparing different cutoff-values of subgroups divided by age, gender and renal function, and which increased monotonically with decreasing of eGFR because in patients with CKD without AMI, the correlation between hs-cTnI and renal function is low but significant (r2 = 0.067, P < 0.001). Conclusions Different optimal cutoff-values of hs-cTnI in the diagnosis of AMI in patients with CKD were helpful to the clinical diagnosis of AMI in various populations and were higher in males than females, but which was needed to be validated by multicenter randomized controlled clinical studies in the future.

scholarly journals Automated tumor proportion scoring for PD-L1 expression based on multistage ensemble strategy in non-small cell lung cancer

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Boju Pan ◽  
Yuxin Kang ◽  
Yan Jin ◽  
Lin Yang ◽  
Yushuang Zheng ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Image Analysis ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Automated Image Analysis ◽  
Small Cell Lung ◽  
Cutoff Values ◽  
Scoring Algorithm ◽  
Better Than

Abstract Introduction Programmed cell death ligand-1 (PD-L1) expression is a promising biomarker for identifying treatment related to non-small cell lung cancer (NSCLC). Automated image analysis served as an aided PD-L1 scoring tool for pathologists to reduce inter- and intrareader variability. We developed a novel automated tumor proportion scoring (TPS) algorithm, and evaluated the concordance of this image analysis algorithm with pathologist scores. Methods We included 230 NSCLC samples prepared and stained using the PD-L1(SP263) and PD-L1(22C3) antibodies separately. The scoring algorithm was based on regional segmentation and cellular detection. We used 30 PD-L1(SP263) slides for algorithm training and validation. Results Overall, 192 SP263 samples and 117 22C3 samples were amenable to image analysis scoring. Automated image analysis and pathologist scores were highly concordant [intraclass correlation coefficient (ICC) = 0.873 and 0.737]. Concordances at moderate and high cutoff values were better than at low cutoff values significantly. For SP263 and 22C3, the concordances in squamous cell carcinomas were better than adenocarcinomas (SP263 ICC = 0.884 vs 0.783; 22C3 ICC = 0.782 vs 0.500). In addition, our automated immune cell proportion scoring (IPS) scores achieved high positive correlation with the pathologists TPS scores. Conclusions The novel automated image analysis scoring algorithm permitted quantitative comparison with existing PD-L1 diagnostic assays and demonstrated effectiveness by combining cellular and regional information for image algorithm training. Meanwhile, the fact that concordances vary in different subtypes of NSCLC samples, which should be considered in algorithm development.

Sex-Specific Cutoff Values for Soluble Suppression of Tumorigenicity 2 (ST2) Biomarker Increase its Cardiovascular Prognostic Value in the Community

Biomarkers ◽  
2021 ◽  
pp. 1-23
Author(s):  
David M. Harmon ◽  
Omar F. Abou Ezzeddine ◽  
Paul M. McKie ◽  
Christopher G. Scott ◽  
Amy K. Saenger ◽  
...  
Keyword(s):  
Prognostic Value ◽  
Cutoff Values

Determination of the optimal cutoff values and validity of the Purdue Pegboard Test

2021 ◽  
pp. 030802262110080
Author(s):  
Ilkem Ceren Sigirtmac ◽  
Cigdem Oksuz
Keyword(s):  
Construct Validity ◽  
Hand Function ◽  
Area Under The Curve ◽  
Hand Injury ◽  
Cutoff Value ◽  
Cutoff Values ◽  
Hand Dexterity ◽  
Valid Instrument ◽  
Healthy Participants

Introduction The Purdue Pegboard Test (PPT) is crucial for assessing fine dexterity of patients with hand injury. Determining the PPT cutoff value is needed to distinguish patients with impaired hand dexterity from those with unimpaired hand dexterity. The aim of this article is to examine the construct validity of PPT and to determine its cutoff values for patients with hand injuries. Method The PPT and Disabilities of Arm Shoulder and Hand Questionnaire Turkish version (DASH-T) were used to measure hand dexterity. To examine construct validity, we measured the correlation between PPT and DASH-T. The cutoff values were determined using the receiver operating characteristic (ROC) curve generated with sensitivity and 1-specificity. We recruited 101 patients with hand injury and 162 healthy participants. Results Correlation between all subtests of PPT and DASH-T were weak ( r = −0.282; −0.473: p<0.05). The cutoff value for the assembly subtest of PPT was 24.5. The range of area under the curve (AUC) values for PPT subtests was good to excellent (AUC: 0.82–0.92). Conclusion The current study demonstrates that PPT is a valid instrument for measuring hand dexterity in patients with hand injury. Results also suggest that PPT distinguished the patients with impaired hand function from those with unimpaired hand dexterity.

scholarly journals Correlation of Ultrasound Findings With Clinical Stages and Impairment in Adhesive Capsulitis of the Shoulder

2021 ◽  
Vol 9 (5) ◽  
pp. 232596712110036
Author(s):  
Jong Geol Do ◽  
Jin Tae Hwang ◽  
Kyung Jae Yoon ◽  
Yong-Taek Lee
Keyword(s):  
Structural Changes ◽  
External Rotation ◽  
Biceps Tendon ◽  
Adhesive Capsulitis ◽  
Case Series ◽  
Tendon Sheath ◽  
Level Of Evidence ◽  
Cutoff Values ◽  
Diagnostic Values ◽  
Ultrasound Parameters

Background: Ultrasound is an essential tool for diagnosing shoulder disorders. However, the role of ultrasound in assessing and diagnosing adhesive capsulitis has not been fully studied. Purpose: To evaluate the ultrasound features of adhesive capsulitis and estimate the correlations between clinical impairment and ultrasound parameters. Study Design: Case series; Level of evidence, 4. Methods: A total of 61 patients with clinically diagnosed unilateral adhesive capsulitis were retrospectively reviewed using high-resolution ultrasound. To compare ultrasound parameters, we performed ultrasound examinations on both affected and unaffected shoulders. Ultrasound parameters, including thickness of the coracohumeral ligament (CHL), rotator interval (RI), axillary recess (AR), hypervascularity of the RI, and effusion of the long head of the biceps tendon sheath, were measured. Passive range of motion (PROM), visual analog scale for pain, and the Shoulder Pain and Disability Index were used for clinical assessment. Results: The CHL, the RI, and the AR in affected shoulders were significantly thicker than in unaffected shoulders ( P < .05). CHL thickness in affected shoulders was significantly correlated with PROM limitation, which included forward elevation, abduction, external rotation (ER), and internal rotation (IR) ( P < .05). AR thickness correlated with passive forward elevation limitation and passive IR limitation ( P < .05). The CHL was significantly thicker in stage 2 compared with stage 1, and the RI was thicker in stage 2 compared with stage 3. The diagnostic cutoff values for adhesive capsulitis were 2.2 mm for CHL thickness (77% sensitivity, 91.8% specificity) and 4 mm for AR thickness (68.9% sensitivity, 90.2% specificity). Conclusion: The ultrasound parameters associated with structural changes were correlated with clinical characteristics of adhesive capsulitis. Thickened CHL, RI, and AR were observed in affected shoulders. The cutoff values of 2.2 mm for CHL thickness and 4 mm for AR thickness can be used as cutoff diagnostic values for adhesive capsulitis.

scholarly journals The Prognostic Value of Preoperative Plasma Fibrinogen and Neutrophil-to-Lymphocyte Ratio in Patients With Laryngeal Squamous Cell Carcinoma

2020 ◽  
pp. 014556132092074
Author(s):  
Hao Cai ◽  
Zi-Heng Zhang ◽  
Yu-Jie Zhou ◽  
Ji Liu ◽  
Huan-Qi Chen ◽  
...  
Keyword(s):  
Squamous Cell Carcinoma ◽  
Cell Carcinoma ◽  
Squamous Cell ◽  
Laryngeal Carcinoma ◽  
Laryngeal Squamous Cell Carcinoma ◽  
Neutrophil To Lymphocyte Ratio ◽  
Plasma Fibrinogen ◽  
Optimal Cutoff ◽  
Lymphocyte Ratio ◽  
Cutoff Values

Objectives: Treatment effects in patients with laryngeal squamous cell carcinoma may vary significantly even among those with the same TNM stage. Routine preoperative blood and coagulation tests are economical and easily available hematological indicators. This study aimed to investigate the clinical predictive significance of pretreatment evaluation of plasma fibrinogen (FIB) level, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) in patients with laryngeal carcinoma. Methods: Clinicopathological and demographic data from 203 patients who underwent surgery for laryngeal carcinoma were collected and analyzed. The optimal cutoff values for FIB, NLR, and PLR were determined using receiver operating characteristic curve analysis. Univariate and multivariate Cox regression analyses were used to study the relationship between blood markers and patient survival. Results: The optimal cutoff values for FIB, NLR, and PLR were 3.05 g/L, 2.41, and 110.94, respectively. Preoperative hyperfibrinemia (FIB >3.05 g/L) was an independent prognostic factor for overall survival (OS) and disease-free survival in patients with laryngeal carcinoma. An NLR >2.41 was associated with reduced OS in patients with laryngeal carcinoma, while PLR >110.94 had no effect on prognosis in these patients. Conclusions: Fibrinogen and NLR were valuable markers in predicting survival in patients with laryngeal carcinoma and may be used to inform clinicians in designing individual treatment strategies.

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