Sensitivity, Specificity, and Predictive Values in the 'Sensitivity and Specificity of Clinical Diagnostics'

Abstract Background and PurposeAlthough many studies have described clinical examination measures for the diagnosis of lumbar spinal instability, few of them have investigated the sensitivity and specificity of the measures that were used. The authors devised a passive lumbar extension (PLE) test for assessing lumbar spinal instability. The purpose of this study was to investigate the sensitivity, specificity, and positive likelihood ratio of this test. Subjects and Methods. The PLE test as well as the instability catch sign, painful catch sign, and apprehension sign tests were done for 122 subjects with lumbar degenerative diseases. The subjects were divided into 2 groups—instability positive and instability negative—on the basis of findings on flexion-extension films of the lumbar spine. The sensitivity, specificity, predictive values, and positive likelihood ratio of each test were investigated. Results. The sensitivity and specificity of the PLE test were 84.2% and 90.4%, respectively. These values were higher than those of other signs. The positive likelihood ratio of the PLE test was 8.84 (95% confidence interval=4.51–17.33). Discussion and Conclusion. The PLE test is an effective method for examining patients for lumbar spinal instability and can be performed easily in an outpatient clinic.

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Urea-Fibrinogen Slide Coagulase Test – A Simple Alternative Method for the Rapid Identification of Staphylococcus aureus

Journal of Gandaki Medical College-Nepal ◽

10.3126/jgmcn.v10i1.17903 ◽

2017 ◽

Vol 10 (1) ◽

pp. 5-10

Author(s):

Binita Koirala Sharma ◽

S Gokhale ◽

K Sharma

Keyword(s):

Staphylococcus Aureus ◽

Sensitivity And Specificity ◽

Reference Method ◽

Cost Effective ◽

Rapid Identification ◽

Accurate Identification ◽

Predictive Values ◽

Negative Results ◽

Animal Pathogens ◽

Sensitivity Specificity

Introduction: The accurate identification of Staphylococcus aureus clinical isolates requires a series of tests. Morphological features and slide coagulase test are two criteria on which S. aureus are identified. Resort to tube coagulase test is sought when results of slide coagulase test are equivocal or doubtful. Both coagulase tests detect the enzymes that convert fibrinogen into fibrin. Human, rabbit or sheep pooled plasma is used as substrate for both tests. Slide coagulase test is simpler and faster as compared to tube coagulase test. The plasma could be carrier of many human and animal pathogens like HIV, HBV, HCV etc. Storage of plasma for longer duration is fraught with chances of contamination. Improperly stored plasma can lead to false positive or negative results. Citrated plasma may be unsuitable for this test if contaminated with citrate utilizing bacteria. Considering the role of S. aureus as a common etiological agent in nosocomial and community infections, there is a need of implementing rapid, easy and cost-effective phenotypic test.Objectives: Considering the disadvantages and risks associated with fresh plasma, this study aims to launch for safer, more reliable substitute with longer shelf life that may provide reliable results for prompt identification of S. aureus by slide coagulase test.Methods: The present work evaluates slide coagulase test (SCT), and urea fibrinogen slide coagulase test (UF-SCT) for S. aureus detection considering Tube coagulase test (TCT) as the reference method. Sensitivity, specificity, positive predictive value and negative predictive values of SCT and UF-SCT were calculated using TCT as gold standard. Results: A total of 150 staphylococcal isolates from different clinical specimens ere selected for the evaluation of coagulase tests. All the specimens were subjected to SCT, UF-SCT and TCT. The UF-SCT showed better sensitivity (95.04%), specificity (100%), PPV (100%), and NPV (82.85%) with reference to TCT. UF-SCT showed similar sensitivity and specificity to SCT. None of the isolates were negative in UF-SCT and positive in SCT. Since UF-SCT does not incorporate plasma directly and at the same time has a very good sensitivity and specificity, it is recommended that UF-SCT could replace SCT for identification of S. aureus.Conclusion: The findings of present study shall encourage laboratories to use the urea-fibrinogen slide coagulase test routinely for the rapid identification of S aureus.Journal of Gandaki Medical College Vol. 10, No. 1, 2017, Page: 5-10

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Validation of an extended French version of ID Migraine™ as a migraine-screening tool

Cephalalgia ◽

10.1177/0333102414544910 ◽

2014 ◽

Vol 35 (5) ◽

pp. 437-442 ◽

Cited By ~ 9

Author(s):

Sylvie Streel ◽

Anne-Françoise Donneau ◽

Nadia Dardenne ◽

Axelle Hoge ◽

Olivier Bruyère ◽

...

Keyword(s):

Sensitivity And Specificity ◽

Screening Tool ◽

Epidemiological Studies ◽

Predictive Values ◽

French Version ◽

Gender Education ◽

French Speaking ◽

Id Migraine ◽

Sensitivity Specificity

Introduction Migraine has a considerable social, economic, physical and emotional burden but remains underdiagnosed and undertreated. A specific migraine screening tool could help remove barriers to health care and be an attractive instrument for epidemiological studies. The objective of this work was to assess the validity of an extended French version of ID Migraine™ as a migraine-screening tool. Methods Sixty-seven subjects from the NESCaV study (2010–2012) completed the migraine screen and were diagnosed by a neurologist specializing in headache medicine using the International Classification of Headache Disorders, 2nd edition criteria (gold standard). Agreement between the two diagnoses was evaluated by Cohen kappa coefficient (κ). Sensitivity, specificity and predictive values of the migraine screen were calculated. Results Migraine was diagnosed in 21 (31.3%) of the 67 subjects according to the screening tool and in 24 (35.8%) by the neurologist (κ = 0.90). The prevalence of migraine was unrelated to age, gender, education and perception of financial resources. Sensitivity and specificity of the screen were 87.5% and 100%, respectively. The screen prevalence of migraine with aura was 10.4% (sensitivity and specificity: 83.3% and 96.7%, respectively). Conclusion The extended French version of ID Migraine™ (ef-ID Migraine) is a validated tool to screen migraine in French-speaking countries.

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Commercial AI solutions in detecting COVID-19 pneumonia in chest CT: not yet ready for clinical implementation?

European Radiology ◽

10.1007/s00330-021-08409-4 ◽

2021 ◽

Author(s):

Florian Jungmann ◽

Lukas Müller ◽

Felix Hahn ◽

Maximilian Weustenfeld ◽

Ann-Kathrin Dapper ◽

...

Keyword(s):

Sensitivity And Specificity ◽

Subgroup Analysis ◽

Chest Ct ◽

Ground Glass ◽

Clinical Implementation ◽

Clinical Routine ◽

Predictive Values ◽

Clinical Dataset ◽

Sensitivity Specificity ◽

Ct Studies

Abstract Objectives In response to the COVID-19 pandemic, many researchers have developed artificial intelligence (AI) tools to differentiate COVID-19 pneumonia from other conditions in chest CT. However, in many cases, performance has not been clinically validated. The aim of this study was to evaluate the performance of commercial AI solutions in differentiating COVID-19 pneumonia from other lung conditions. Methods Four commercial AI solutions were evaluated on a dual-center clinical dataset consisting of 500 CT studies; COVID-19 pneumonia was microbiologically proven in 50 of these. Sensitivity, specificity, positive and negative predictive values, and AUC were calculated. In a subgroup analysis, the performance of the AI solutions in differentiating COVID-19 pneumonia from other conditions was evaluated in CT studies with ground-glass opacities (GGOs). Results Sensitivity and specificity ranges were 62–96% and 31–80%, respectively. Negative and positive predictive values ranged between 82–99% and 19–25%, respectively. AUC was in the range 0.54–0.79. In CT studies with GGO, sensitivity remained unchanged. However, specificity was lower, and ranged between 15 and 53%. AUC for studies with GGO was in the range 0.54–0.69. Conclusions This study highlights the variable specificity and low positive predictive value of AI solutions in diagnosing COVID-19 pneumonia in chest CT. However, one solution yielded acceptable values for sensitivity. Thus, with further improvement, commercial AI solutions currently under development have the potential to be integrated as alert tools in clinical routine workflow. Randomized trials are needed to assess the true benefits and also potential harms of the use of AI in image analysis. Key Points • Commercial AI solutions achieved a sensitivity and specificity ranging from 62 to 96% and from 31 to 80%, respectively, in identifying patients suspicious for COVID-19 in a clinical dataset. • Sensitivity remained within the same range, while specificity was even lower in subgroup analysis of CT studies with ground-glass opacities, and interrater agreement between the commercial AI solutions was minimal to nonexistent. • Thus, commercial AI solutions have the potential to be integrated as alert tools for the detection of patients with lung changes suspicious for COVID-19 pneumonia in a clinical routine workflow, if further improvement is made.

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VAGINAL SONOGRAPHY a HYSTEROSCOPY

The Professional Medical Journal ◽

10.29309/tpmj/2009.16.03.2873 ◽

2009 ◽

Vol 16 (03) ◽

pp. 432-437

Author(s):

MASOMEH ASGHARNIA ◽

Zahra Mohammad Tabar ◽

MARZIEH MEHRAFZA ◽

Mary am Shakiba ◽

MONA OUDI ◽

...

Keyword(s):

Sensitivity And Specificity ◽

Uterine Cavity ◽

Cross Sectional Study ◽

Therapeutic Modality ◽

Histological Evaluation ◽

Complete Evaluation ◽

Cross Sectional ◽

Predictive Values ◽

Infertile Women ◽

Sensitivity Specificity

B a c k g r o u n d : Hysteroscopy is a valuable diagnostic and therapeutic modality in the management of infertility. A i m : To evaluatethe consistency of hysteroscopy based on a histopathological report from endometrial specimens for intrauterine disorders. Materials andMethods: This is a cross-sectional study. The study included 115 infertile patients. All were admitted for investigation of infertile women beforeassisted reproduction in Mehr infertility institute between 2006 and 2007 hysteroscopy, and histological evaluation of endometrial biopsyperformed.We compared the efficacy of hysteroscopy in the diagnosis of benign intrauterine pathology in infertile women in whom the diagnosiswas confirmed by histologic studies. The women had a complete evaluation with preoperative hysteroscopy, and histological analysis of uterinecavity specimens. Sensitivity, specificity, predictive and negative predictive values were calculated for hysteroscopy considering the histologicalstudy as 100%. Results: Sensitivity and specificity of sonography in diagnosing the polyp were stated 81 % and 64% respectively. Sensitivityand specificity of hysteroscopy showed of polyps revealed 85% and 84% respectively. The results indicated that Sensitivity and specificity ofsonography in diagnosing the myoma were 25% and 98% respectively. Sensitivity and specificity of hysteroscopy in diagnosing the myomawere expressed 50% and 93% respectively. C o n c l u s i o n : Hysteroscopy is a safe and rapid direct visualisation of the uterine cavity. We believeit should be replaced by the diagnostic hysteroscopy as a first line infertility investigation.

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