Why Almost Always Animals? Ranking Fluency Tasks for the Detection of Dementia Based on Receiver Operating Characteristic (ROC) and Quality ROC Analyses

2016 ◽  
Vol 43 (1-2) ◽  
pp. 59-70 ◽  
Author(s):  
F. Javier Moreno-Martínez ◽  
Marcos Ruiz ◽  
Pedro R. Montoro
Keyword(s):  
Receiver Operating Characteristic ◽  
Sensitivity And Specificity ◽  
Operating Characteristic ◽  
Empirical Evaluation ◽  
Empirical Support ◽  
Roc Curves ◽  
Semantic Categories ◽  
Healthy Elderly ◽  
Category Fluency ◽  
Receiver Operating

Background/Aims: Category fluency tasks have been widely used to assess cognitive functioning in both clinical and experimental environments as an index of cognitive and psycholinguistic dysfunctions in dementia. Typically, a reduced group of semantic categories has been selected for neuropsychological assessment (e.g., animals, fruits or vegetables), although empirical support for the prevalence of one category among others is absent in the literature. Methods: We provide an empirical evaluation of the ability of 14 category fluency tasks to discriminate between subjects with dementia of the Alzheimer type and healthy elderly participants. As a novelty, we used both receiver operating characteristic (ROC) curves and quality ROC calibrated analyses to characterize the interplay of sensitivity and specificity of every category fluency task performance as a screening tool. The use of calibrated measures provided us with a useful tool for comparing the diagnostic ability of the different categories, as well as making rankings of categories based on the quality indices of efficiency, sensitivity, and specificity. Results: The habitually used category of animals is far from being the most efficient one in terms of its diagnostic power to evaluate dementia. Conclusion: Our study might guide the selection of suitable category fluency tasks according to the diagnostic purposes in dementia.

Diagnostic studies

2010 ◽  
pp. 339-351
Author(s):  
Janet L. Peacock ◽  
Philip J. Peacock
Keyword(s):  
Receiver Operating Characteristic ◽  
Likelihood Ratio ◽  
Sensitivity And Specificity ◽  
Operating Characteristic ◽  
Characteristic Curve ◽  
Diagnostic Testing ◽  
Roc Curves ◽  
Clinical Situation ◽  
Post Test ◽  
Receiver Operating

Sensitivity and specificity 340 Calculations for sensitivity and specificity 342 Effect of prevalence 344 Likelihood ratio, pre-test odds, post-test odds 346 Receiver operating characteristic (ROC) curves 348 Links to other statistics 350 In this chapter we describe how statistical methods are used in diagnostic testing to obtain different measures of a test’s performance. We describe how to calculate sensitivity, specificity, and positive and negative predictive values, and show the relevance of pre- and post-test odds and likelihood ratio in evaluating a test in a clinical situation. We also describe the receiver operating characteristic curve and show how this links with logistic regression analysis. All methods are illustrated with examples....

Single group studies

2017 ◽  
Author(s):  
Janet L. Peacock ◽  
Sally M. Kerry ◽  
Raymond R. Balise
Keyword(s):  
Receiver Operating Characteristic ◽  
Sensitivity And Specificity ◽  
Operating Characteristic ◽  
Rare Condition ◽  
Roc Curves ◽  
Single Group ◽  
Receiver Operating

Chapter 6 discusses single group studies, and covers prevalence, how to present results, screening studies, calculating, and presenting sensitivity and specificity. It discusses how to deal with calculations with a rare condition where the numbers are small. Finally, it discusses the use of receiver operating characteristic (ROC) curves. The chapter includes analyses using Stata, SAS, SPSS, and R.

Use of Receiver Operating Characteristic (ROC) Curves to Evaluate Computer Confidence Threshold and Clinical Performance in the Diagnosis of Appendicitis

1978 ◽  
Vol 17 (03) ◽  
pp. 157-161 ◽  
Author(s):  
F. T. De Dombal ◽  
Jane C. Horrocks
Keyword(s):  
Receiver Operating Characteristic ◽  
Operating Characteristic ◽  
Clinical Performance ◽  
Roc Curves ◽  
Final Diagnosis ◽  
Confidence Threshold ◽  
Computer Aided ◽  
Computer Confidence ◽  
Overall Performance ◽  
Receiver Operating

This paper uses simple receiver operating characteristic (ROC) curves (i) to study the effect of varying computer confidence of threshold levels and (ii) to evaluate clinical performance in the diagnosis of acute appendicitis. Over 1300 patients presenting to five centres with abdominal pain of short duration were studied in varying detail. Clinical and computer-aided diagnostic predictions were compared with the »final« diagnosis. From these studies it is concluded the simplistic setting of a 50/50 confidence threshold for the computer program is as »good« as any other. The proximity of a computer-aided system changed clinical behaviour patterns; a higher overall performance level was achieved and clinicians performance levels became associated with the »mildly conservative« end of the computers ROC curve. Prior forecasts of over-confidence or ultra-caution amongst clinicians using the computer-aided system have not been fulfilled.

scholarly journals MicroRNAs-1299, -126-3p and -30e-3p as Potential Diagnostic Biomarkers for Prediabetes

Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 949
Author(s):  
Cecil J. Weale ◽  
Don M. Matshazi ◽  
Saarah F. G. Davids ◽  
Shanel Raghubeer ◽  
Rajiv T. Erasmus ◽  
...  
Keyword(s):  
Receiver Operating Characteristic ◽  
Operating Characteristic ◽  
Characteristic Curve ◽  
Predictive Ability ◽  
Roc Curves ◽  
Tolerance Test ◽  
Cross Sectional Study ◽  
Oral Glucose ◽  
Cross Sectional ◽  
Receiver Operating

This cross-sectional study investigated the association of miR-1299, -126-3p and -30e-3p with and their diagnostic capability for dysglycaemia in 1273 (men, n = 345) South Africans, aged >20 years. Glycaemic status was assessed by oral glucose tolerance test (OGTT). Whole blood microRNA (miRNA) expressions were assessed using TaqMan-based reverse transcription quantitative-PCR (RT-qPCR). Receiver operating characteristic (ROC) curves assessed the ability of each miRNA to discriminate dysglycaemia, while multivariable logistic regression analyses linked expression with dysglycaemia. In all, 207 (16.2%) and 94 (7.4%) participants had prediabetes and type 2 diabetes mellitus (T2DM), respectively. All three miRNAs were significantly highly expressed in individuals with prediabetes compared to normotolerant patients, p < 0.001. miR-30e-3p and miR-126-3p were also significantly more expressed in T2DM versus normotolerant patients, p < 0.001. In multivariable logistic regressions, the three miRNAs were consistently and continuously associated with prediabetes, while only miR-126-3p was associated with T2DM. The ROC analysis indicated all three miRNAs had a significant overall predictive ability to diagnose prediabetes, diabetes and the combination of both (dysglycaemia), with the area under the receiver operating characteristic curve (AUC) being significantly higher for miR-126-3p in prediabetes. For prediabetes diagnosis, miR-126-3p (AUC = 0.760) outperformed HbA1c (AUC = 0.695), p = 0.042. These results suggest that miR-1299, -126-3p and -30e-3p are associated with prediabetes, and measuring miR-126-3p could potentially contribute to diabetes risk screening strategies.

scholarly journals Correction to: Cut-off points between pain intensities of the postoperative pain using receiver operating characteristic (ROC) curves

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Sooyoung Cho ◽  
Youn Jin Kim ◽  
Minjin Lee ◽  
Jae Hee Woo ◽  
Hyun Jung Lee
Keyword(s):  
Postoperative Pain ◽  
Receiver Operating Characteristic ◽  
Operating Characteristic ◽  
Roc Curves ◽  
Receiver Operating

scholarly journals Diagnostic performances of manual and automated reticulocyte parameters in anaemic cats

2017 ◽  
Vol 20 (2) ◽  
pp. 122-127 ◽  
Author(s):  
Saverio Paltrinieri ◽  
Marco Fossati ◽  
Valentina Menaballi
Keyword(s):  
Receiver Operating Characteristic ◽  
Sensitivity And Specificity ◽  
Operating Characteristic ◽  
Positive Likelihood Ratio ◽  
Roc Curves ◽  
Blood Samples ◽  
Production Index ◽  
Instrumental Measurement ◽  
Sensitivity Specificity ◽  
Reticulocyte Production

Objectives The objective of this study was to evaluate the diagnostic performances of manual and instrumental measurement of reticulocyte percentage (Ret%), reticulocyte number (Ret#) and reticulocyte production index (RPI) to differentiate regenerative anaemia (RA) from non-regenerative anaemia (NRA) in cats. Methods Data from 106 blood samples from anaemic cats with manual counts (n = 74; 68 NRA, six RA) or instrumental counts of reticulocytes (n = 32; 25 NRA, seven RA) collected between 1995 and 2013 were retrospectively analysed. Sensitivity, specificity and positive likelihood ratio (LR+) were calculated using either cut-offs reported in the literature or cut-offs determined from receiver operating characteristic (ROC) curves. Results All the reticulocyte parameters were significantly higher in cats with RA than in cats with NRA. All the ROC curves were significantly different ( P <0.001) from the line of no discrimination, without significant differences between the three parameters. Using the cut-offs published in literature, the Ret% (cut-off: 0.5%) was sensitive (100%) but not specific (<75%), the RPI (cut-off: 1.0) was specific (>92%) but not sensitive (<15%), and the Ret# (cut-off: 50 × 10³/µl) had a sensitivity and specificity >80% and the highest LR+ (manual count: 14; instrumental count: 6). For all the parameters, sensitivity and specificity approached 100% using the cut-offs determined by the ROC curves. These cut-offs were higher than those reported in the literature for Ret% (manual: 1.70%; instrumental: 3.06%), lower for RPI (manual: 0.39; instrumental: 0.59) and variably different, depending on the method (manual: 41 × 10³/µl; instrumental: 57 × 10³/µl), for Ret#. Using these cut-offs, the RPI had the highest LR+ (manual: 22.7; instrumental: 12.5). Conclusions and relevance This study indicated that all the reticulocyte parameters may confirm regeneration when the pretest probability is high, while when this probability is moderate, RA should be identified using the RPI providing that cut-offs <1.0 are used.

SOME EFFECTS OF IMAGE SEGMENTATION ON SUBSPACE-BASED AND COVARIANCE-BASED DETECTION OF ANOMALOUS SUB-PIXEL MATERIALS

2008 ◽  
Vol 18 (02) ◽  
pp. 349-367
Author(s):  
CHRISTOPHER GITTINS ◽  
DAISEI KONNO ◽  
MICHAEL HOKE ◽  
ANTHONY RATKOWSKI
Keyword(s):  
Receiver Operating Characteristic ◽  
Operating Characteristic ◽  
Roc Curves ◽  
Synthetic Spectrum ◽  
Ratio Test ◽  
Probability Of False Alarm ◽  
Near Ir ◽  
Data Segmentation ◽  
Material Detection ◽  
Receiver Operating

In this paper we assess the effect that clustering pixels into spectrally-similar background types, for example, soil, vegetation, and water in hyperspectral visible/near-IR/SWIR imagery, prior to applying a detection methodology has on material detection statistics. Specifically, we examine the effects of data segmentation on two statistically-based detection metrics, the Subspace Generalized Likelihood Ratio Test (Subspace GLRT) and the Adaptive Cosine Estimator (ACE), applied to a publicly-available AVIRIS datacube augmented with a synthetic material spectrum in selected pixels. The use of synthetic spectrum-augmented data enables quantitative comparison of Subspace-GLRT and ACE using Receiver Operating Characteristic (ROC) curves. For all cases investigated, Receiver Operating Characteristic (ROC) curves generated using ACE were as good as or superior to those generated using Subspace-GLRT. The favorability of ACE over Subspace-GLRT was more pronounced as the synthetic spectrum mixing fraction decreased. For probabilities of detection in the range of 50-80%, segmentation reduced the probability of false alarm by a factor of 3–5 when using ACE. In contrast, segmentation had no apparent effect on detection statistics using Subspace-GLRT, in this example.

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