Sensitivity and specificity of Sirius indices in diagnosis of keratoconus and suspect keratoconus

2021 ◽  
pp. 112067212110601
Author(s):  
Abdelrahman Salman ◽  
Taym Darwish ◽  
Ali Ali ◽  
Marwan Ghabra ◽  
Rafea Shaaban
Keyword(s):  
Sensitivity And Specificity ◽  
Predictive Accuracy ◽  
Corneal Thickness ◽  
Case Series ◽  
Area Under The Curve ◽  
Receiver Operating Characteristics ◽  
Operating Characteristics ◽  
Symmetry Index ◽  
Case Series Study ◽  
Receiver Operating

Aim To estimate the sensitivity and specificity of topographic and tomographic corneal parameters as determined by Sirius (CSO, Florence, Italy) in discriminating keratoconus (KC) and suspect keratoconus from normal cornea. Method In this retrospective case-series study, keratoconus screening indices were measured using Sirius tomographer. Receiver operating characteristics (ROC) curves were used to determine the test's overall predictive accuracy (area under the curve) and to identify optimal cut-off points to maximize sensitivity and specificity in differentiating keratoconus and suspect keratoconus from normal corneas. Results Receiver operating characteristics (ROC) curve analyses showed high predictive accuracy for Symmetry Index back (SIb), Keratoconus Vertex front (KVf), Symmetry Index front (SIf), Keratoconus Vertex back (KVb), Apex Keratometry (Curve-Apex) and Minimum corneal Thickness (ThkMin) to distinguish keratoconus from normal (area under the curve > 0.9, all). Symmetry Index back was identified as the best diagnostic parameter for detecting suspect keratoconus with AUC of 0.86. Highest specificity to detect keratoconus and suspect keratoconus was seen for SIb, 99.87% and 84.66%, respectively. These values were associated with optimal cut-off points of 0.46 D for keratoconus and 0.12 D for suspect keratoconus. Conclusion Sirius parameters evaluated in the study were effective to differentiate keratoconus from normal corneas. However, Symmetry Index back was the index with the highest ability to detect suspect keratoconus.

Abstract P337: RAPID-LVO for Automated Detection of Intracranial Large Vessel Occlusion in Ct Angiography of the Brain

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Seena Dehkharghani ◽  
Maarten G Lansberg ◽  
Chitra Venkatsubramanian ◽  
carlo W cereda ◽  
Fabricio O Lima ◽  
...  
Keyword(s):  
Ct Angiography ◽  
Sensitivity And Specificity ◽  
Large Vessel ◽  
Receiver Operating Characteristics ◽  
Subspecialty Training ◽  
Emergency Setting ◽  
Large Vessel Occlusion ◽  
Operating Characteristics ◽  
Vessel Occlusion ◽  
Receiver Operating

Background: Identification of large vessel occlusion (LVO) is paramount in the urgent evaluation of acute ischemic stroke (AIS). Emergent interpretation of large and high-complexity data sets, however, may impose strains upon imaging and clinical workflows, motivating development of fast and accurate computer-aided approaches to facilitate LVO detection in the emergency setting. This study investigates the performance of a fully automated LVO detection platform in a mixed cohort of stroke subjects with and without LVO on head and neck CT angiography (CTA). Methods: CTA from two cerebrovascular trials were enriched with cases from eleven global sites. Imaging and clinical variables were balanced between populations including in LVO positivity and across demographic and imaging environments to the extent achievable. Independent and fully blinded review for intracranial ICA or MCA M1 LVO was performed by two subspecialty neuroradiologists. A novel, user-independent imaging analysis application ( RAPID-LVO , iSchemaview inc) was used to predict LVO presence, location, and overall performance relative to reader consensus. Any discordance between readers was adjudicated by a blinded tertiary reader with subspecialty training. Sensitivity, specificity, and receiver-operating characteristics were determined by an independent statistician. Performance thresholds were set a priori, including a lower bound of the 95% CI of sensitivity and specificity of ≥0.8 at mean times-to-notification <3.5 minutes. Results: 217 CTA (median age 65.5, 53% male, 109 LVO(+)) were included. Lower confidence limits of sensitivity and specificity exceeded 90% (sensitivity 0.963, 95% CI 0.909-0.986; specificity 0.981, 95% CI 0.935-0.995), surpassing pre-specified performance benchmarks. Subgroup analyses revealed no decrement in performance relative to subject age or sex, vendor systems, or location of the examination within or outside the United States. The area under the receiver operating characteristics curve was 0.99 (95% CI: 0.971-0.999) and average time-to-notification was 3.18 minutes. Conclusion: RAPID-LVO offers fast, highly accurate, and fully user-independent large vessel occlusion detection across all tested clinical and imaging environments.

Depressions-Screening bei pädiatrischen Patienten

2012 ◽  
Vol 40 (3) ◽  
pp. 161-169 ◽  
Author(s):  
Barbara Frühe ◽  
Antje-Kathrin Allgaier ◽  
Kathrin Pietsch ◽  
Gerd Schulte-Körne
Keyword(s):  
Kinder Und Jugendliche ◽  
Area Under The Curve ◽  
Receiver Operating Characteristics ◽  
Youden Index ◽  
Operating Characteristics ◽  
Children’S Depression ◽  
Icd 10 ◽  
Receiver Operating

Fragestellung: Für das Screening depressiver Störungen im pädiatrischen Kontext wurde die konkurrente Validität des Depressionsinventars für Kinder und Jugendliche (DIKJ), der Skala Dysphorie aus dem Depressionstest für Kinder (DTK) und des Children’s Depression Screeners (ChilD-S) in Bezug auf ICD-10-Depressionsdiagnosen bei somatisch erkrankten Kindern verglichen. Methodik: Die Daten von 9- bis 12-jährigen pädiatrischen Patienten (N = 228) wurden mittels Receiver Operating Characteristics analysiert. Die daraus ableitbaren Kennwerte wie Area Under the Curve (AUC), Sensitivität (SE) und Spezifität (SP) wurden für jedes Instrument berechnet und miteinander verglichen. Als Goldstandard dienten Depressionsdiagnosen nach ICD-10, erhoben anhand des klinischen Interviews Kinder-DIPS. Ergebnisse: Die konkurrente Validität des 26 Items umfassenden DIKJ war sehr hoch (AUC = 92.6 %), der 25 Items umfassenden Skala Dysphorie zufriedenstellend (AUC = 86.2 %) und des 8 Items umfassenden ChilD-S hervorragend (AUC = 97.5 %); der ChilD-S war dem DIKJ signifikant überlegen. Nach dem Youden-Index sind folgende Cut-Off-Werte zu empfehlen: DIKJ ≥ 12 (SE = 91.7 %, SP = 81.9 %), Skala Dysphorie ≥ 10 (SE = 75.0 %, SP = 89.8 %) und ChilD-S ≥ 10 (SE ≥ 100 %, SP = 86.6 %). Schlussfolgerungen: Sowohl das DIKJ als auch der ChilD-S zeigte eine ausgezeichnete konkurrente Validität für das Screening depressiver Störungen bei pädiatrischen Patienten. Im Vergleich dazu erreichte die Skala Dysphorie etwas niedrigere Validitätsmaße. Für die Implementierung im zeitbegrenzten pädiatrischen Versorgungsalltag ist das ökonomische Verfahren ChilD-S zu favorisieren.

scholarly journals Development of a Brief Pre-Implementation Screening Tool to Identify Teachers Who Are at Risk for Not Implementing Intervention Curriculum and High-Implementing Teachers

2016 ◽  
Vol 44 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Bo Wang ◽  
Bonita Stanton ◽  
Sonja Lunn ◽  
Pooja Patel ◽  
Veronica Koci ◽  
...  
Keyword(s):  
Sensitivity And Specificity ◽  
Screening Tool ◽  
Receiver Operating Characteristics ◽  
Operating Characteristics ◽  
High Performing ◽  
Hiv Intervention ◽  
School Based ◽  
National Implementation ◽  
School Based Interventions ◽  
Receiver Operating

Few questionnaires have been developed to screen for potentially poor implementers of school-based interventions. This study combines teacher characteristics, perceptions, and teaching/training experiences to develop a short screening tool that can identify potential “low-performing” or “high-performing” teachers pre-implementation. Data were gathered from 208 teachers and 4,411 students who participated in the national implementation of an evidence-based HIV intervention in The Bahamas. Sensitivity and specificity were evaluated for the detection of “low-performing” and “high-performing” teachers. The validity of the screening tool was assessed using receiver operating characteristics analysis. The School Pre-implementation Screening Tool consists of seven predictive factors: duration as teacher, working site, attendance at training workshops, training in interactive teaching, perceived importance of the intervention, comfort in teaching the curriculum, and program priority. The sensitivity and specificity were 74% and 57% in identifying “low-performing” teachers and 81% and 65% with “high-performing” teachers. The screening tool demonstrated an acceptable/good validity (area under the receiver operating characteristics curve was 0.68 for “low-performing teachers” and 0.78 for “high-performing” teachers). Our brief screening tool can facilitate teacher training and recruitment of engaged teachers in implementation of school-based interventions.

scholarly journals Differenzierung von Angststörungen im Elternurteil: Untersuchung anhand des Fragebogens für Angst- und Zwangsstörungen (FBB-ANZ)

2021 ◽  
pp. 1-12
Author(s):  
Andreas M. Mühlherr ◽  
Afsheen Yousaf ◽  
Christine M. Freitag
Keyword(s):  
Area Under The Curve ◽  
Receiver Operating Characteristics ◽  
Operating Characteristics ◽  
Receiver Operating

Zusammenfassung. Im Rahmen der Abklärung des Verdachts einer Angststörung kommen in der klinischen Praxis regelmäßig Screeningfragebögen für Eltern zum Einsatz, die teilweise auch unterschiedliche Angststörungen erfassen. Im klinischen Kontext ist die valide Abgrenzung von Angststörungen zu anderen psychischen Störung sowie die differenzialdiagnostische Abklärung spezifischer Angststörungen relevant. Das Ziel der vorliegenden Studie ist die Untersuchung der Validität eines Screenings durch den Fremdbeurteilungsbogen für Angst- und Zwangsstörungen (FBB-ANZ) hinsichtlich unterschiedlicher Angststörungen. Überprüft wurde die Diskriminationsfähigkeit von (1) Angststörungen und anderen kinder- und jugendpsychiatrischen Störungen und (2) verschiedenen Angststörungen mittels ROC-Analysen (Receiver Operating Characteristics). Der FBB-ANZ wurde von 972 Eltern von 4;00–11;11-jährigen Kindern und 12;00–17;11-jährigen Jugendlichen mit Angststörungen oder depressiven Episoden oder externalisierenden Störungen ausgefüllt. Die Diskriminationsfähigkeit von Angststörungen und externalisierenden Störungen bei Kindern (AUC [Area Under the Curve] = .72) und Jugendlichen (AUC = .76) sowie von Angststörungen und depressiven Episoden im Kindesalter (AUC = .77) war moderat. Eine gute Unterscheidung verschiedener Angststörungen bei Angstpatient_innen war nur hinsichtlich der emotionalen Störung mit Trennungsangst bei Kindern (AUC = .84) und Jugendlichen (AUC = .87) gegeben. Die Ergebnisse deuten auf einen eingeschränkten diagnostischen Nutzen des Screeningurteils der Eltern zur Unterscheidung verschiedener Angststörungen im Kindes- und Jugendalter hin. Mögliche Erklärungsansätze für die vorliegenden Ergebnisse werden kritisch diskutiert.

scholarly journals Comparative Analysis of Anterior Segment Parameters in Normal and Keratoconus Eyes Generated by Scheimpflug Tomography

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Faik Orucoglu ◽  
Ebru Toker
Keyword(s):  
Receiver Operating Characteristic Curve ◽  
Receiver Operating Characteristic ◽  
Sensitivity And Specificity ◽  
Operating Characteristic ◽  
Predictive Accuracy ◽  
Characteristic Curve ◽  
Anterior Segment ◽  
Area Under The Curve ◽  
Operating Characteristic Curve ◽  
Receiver Operating

Purpose. To assess and compare the anterior and posterior corneal surface parameters, keratoconus indices, thickness profile data, and data from enhanced elevation maps of keratoconic and normal corneas with the Pentacam Scheimpflug corneal tomography and to determine the sensitivity and specificity of these parameters in discriminating keratoconus from normal eyes.Methods. The study included 656 keratoconus eyes and 515 healthy eyes with a mean age of30.95±9.25and32.90±14.78years, respectively. Forty parameters obtained from the Pentacam tomography were assessed by the receiver operating characteristic curve analysis for their efficiency.Results. Receiver operating characteristic curve analyses showed excellent predictive accuracy (area under the curve, ranging from 0.914 to 0.972) for 21 of the 40 parameters evaluated. Among all parameters indices of vertical asymmetry, keratoconus index, front elevation at thinnest location, back elevation at thinnest location, Ambrósio Relational Thickness (ARTmax), deviation of average pachymetric progression, deviation of ARTmax, and total deviation showed excellent (>90%) sensitivity and specificity in addition to excellent area under the receiver operating characteristic curve (AUROC).Conclusions. Parameters derived from the topometric and Belin-Ambrósio enhanced ectasia display maps very effectively discriminate keratoconus from normal corneas with excellent sensitivity and specificity.

Kriteriumsbezogene Cut-Off-Werte für Tätigkeitsspielraum und Arbeitsintensität

Diagnostica ◽  
2019 ◽  
Vol 65 (3) ◽  
pp. 179-190 ◽  
Author(s):  
Vincent Mustapha ◽  
Renate Rau
Keyword(s):  
Receiver Operating Characteristics ◽  
Operating Characteristics ◽  
Receiver Operating

Zusammenfassung. Cut-Off-Werte ermöglichen eine ökonomische, binäre Beurteilung von Summenscores. Für Beanspruchungsfragebögen, die personenbezogene Merkmale erfragen, sind Cut-Off-Werte häufig vorhanden und in der klinischen Diagnostik unerlässlich. Für die Bewertung von Arbeitsmerkmalen sind Cut-Off-Werte ebenfalls wünschenswert. Bislang fehlen sie jedoch für die Beurteilung von Arbeitsmerkmalen wie Arbeitsintensität und Tätigkeitsspielraum. Zwischen 2006 und 2016 wurden daher in verschiedenen Branchen 801 objektive Arbeitsplatzanalysen durchgeführt, welche eine Unterteilung in gut und schlecht gestalteten Tätigkeitsspielraum sowie gut und schlecht gestaltete Arbeitsintensität nach DIN EN ISO 6385 (2016) ermöglichen. Anhand dieser Unterteilung wurden mit der Receiver-Operating-Characteristics-Analyse Cut-Off-Werte für den subjektiv-bedingungsbezogen Fragebogen zum Erleben von Arbeitsintensität und Tätigkeitsspielraum (FIT; Richter et al., 2000 ) ermittelt. Für den Tätigkeitsspielraum weisen Summenscores ≤ 22 und für die Arbeitsintensität Summenscores ≥ 15 auf eine schlechte Gestaltung des jeweiligen Arbeitsmerkmals hin. Anhand einer weiteren Stichprobe von 1 076 Arbeitenden konnte gezeigt werden, dass Arbeitende mit schlecht gestaltetem Tätigkeitspielraum vital erschöpfter sowie weniger engagiert sind und Arbeitende mit schlecht gestalteter Arbeitsintensität eine höhere Erholungsunfähigkeit sowie vitale Erschöpfung aufweisen.

scholarly journals Arterial Digital Pulse Photoplethysmography in Patients with Suspected Thoracic Outlet Syndrome: A Study of the “Ca+Pra” Maneuver

Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1128
Author(s):  
Jeanne Hersant ◽  
Pierre Ramondou ◽  
Francine Thouveny ◽  
Mickael Daligault ◽  
Mathieu Feuilloy ◽  
...  
Keyword(s):  
Thoracic Outlet Syndrome ◽  
Pulse Amplitude ◽  
Receiver Operating Characteristics ◽  
Upper Limbs ◽  
Operating Characteristics ◽  
Digital Pulse ◽  
Arterial Inflow ◽  
Receiver Operating

The level of pulse amplitude (PA) change in arterial digital pulse plethysmography (A-PPG) that should be used to diagnose thoracic outlet syndrome (TOS) is debated. We hypothesized that a modification of the Roos test (by moving the arms forward, mimicking a prayer position (“Pra”)) releasing an eventual compression that occurs in the surrender/candlestick position (“Ca”) would facilitate interpretation of A-PPG results. In 52 subjects, we determined the optimal PA change from rest to predict compression at imaging (ultrasonography +/− angiography) with receiver operating characteristics (ROC). “Pra”-PA was set as 100%, and PA was expressed in normalized amplitude (NA) units. Imaging found arterial compression in 23 upper limbs. The area under ROC was 0.765 ± 0.065 (p < 0.0001), resulting in a 91.4% sensitivity and a 60.9% specificity for an increase of fewer than 3 NA from rest during “Ca”, while results were 17.4% and 98.8%, respectively, for the 75% PA decrease previously proposed in the literature. A-PPG during a “Ca+Pra” test provides demonstrable proof of inflow impairment and increases the sensitivity of A-PPG for the detection of arterial compression as determined by imaging. The absence of an increase in PA during the “Ca” phase of the “Ca+Pra” maneuver should be considered indicative of arterial inflow impairment.

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