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ROC Analysis (roc + analysis)
Selected AbstractsImaging of Mandibular Trauma: ROC AnalysisACADEMIC EMERGENCY MEDICINE, Issue 7 2001Dipl., Madhu K. Nair BDS Objectives: To compare the diagnostic efficacies of panoramic radiographs, mandibular trauma series, and digitized radiographs for detection of fractures of the mandible. Methods: Fractures were induced using blunt trauma in 25 cadaver mandibles. Panoramic radiographs, digitized radiographs, and mandibular series comprising an anteroposterior view, two lateral oblique, and a reverse Towne's were used. Six observers recorded their diagnoses using a five-point confidence rating scale. The data were analyzed using receiver operating characteristic (ROC) curve analysis. Results: Significant differences based on imaging modalities were found (p < 0.0015) in the area under the curves (Az): panoramic radiograph, 0.8762; mandibular series, 0.7521; panoramic plus anteroposterior radiographs combination, 0.8886; and digitized mandibular series, 0.7723. No observer-based differences were noted. Condylar and coronoid fractures were difficult to detect than those in other areas of the mandible (p < 0.033). Intra- and inter-observer agreements were high (,w= 0.81 and 0.76, respectively). Conclusions: Panoramic radiographs are adequate for detection of mandibular fractures. Addition of an anteroposterior view augments diagnostic accuracy. [source] Plasma microRNAs are promising novel biomarkers for early detection of colorectal cancerINTERNATIONAL JOURNAL OF CANCER, Issue 1 2010Zhaohui Huang Abstract MicroRNA (miRNA) opens up a new field for molecular diagnosis of cancer. However, the role of circulating miRNAs in plasma/serum in cancer diagnosis is not clear. The aim of this study was to investigate whether plasma miRNAs can be used as biomarkers for the early detection of colorectal carcinoma (CRC). We measured the levels of 12 miRNAs (miR-134, ,146a, ,17-3p, ,181d, ,191, ,221, ,222, ,223, ,25, ,29a, ,320a and ,92a) in plasma samples from patients with advanced colorectal neoplasia (carcinomas and advanced adenomas) and healthy controls using real-time RT-PCR. We found that plasma miR-29a and miR-92a have significant diagnostic value for advanced neoplasia. MiR-29a yielded an AUC (the areas under the ROC curve) of 0.844 and miR-92a yielded an AUC of 0.838 in discriminating CRC from controls. More importantly, these 2 miRNAs also could discriminate advanced adenomas from controls and yielded an AUC of 0.769 for miR-29a and 0.749 for miR-92a. Combined ROC analyses using these 2 miRNAs revealed an elevated AUC of 0.883 with 83.0% sensitivity and 84.7% specificity in discriminating CRC, and AUC of 0.773 with 73.0% sensitivity and 79.7% specificity in discriminating advanced adenomas. Collectively, these data suggest that plasma miR-29a and miR-92a have strong potential as novel noninvasive biomarkers for early detection of CRC. [source] Diagnostic Accuracy of a New Instrument for Detecting Cognitive Dysfunction in an Emergent Psychiatric Population: The Brief Cognitive ScreenACADEMIC EMERGENCY MEDICINE, Issue 3 2010Steven P. Cercy PhD Abstract Objectives:, In certain clinical contexts, the sensitivity of the Mini-Mental State Examination (MMSE) is limited. The authors developed a new cognitive screening instrument, the Brief Cognitive Screen (BCS), with the aim of improving diagnostic accuracy for cognitive dysfunction in the psychiatric emergency department (ED) in a quick and convenient format. Methods:, The BCS, consisting of the Oral Trail Making Test (OTMT), animal fluency, the Clock Drawing Test (CDT), and the MMSE, was administered to 32 patients presenting with emergent psychiatric conditions. Comprehensive neuropsychological evaluation served as the criterion standard for determining cognitive dysfunction. Diagnostic accuracy of the MMSE was determined using the traditional clinical cutoff and receiver operating characteristic (ROC) curve analyses. Diagnostic accuracy of individual BCS components and BCS Summary Scores was determined by ROC analyses. Results:, At the traditional clinical cutoff, MMSE sensitivity (46.4%) and total diagnostic accuracy (53.1%) were inadequate. Under ROC analyses, the diagnostic accuracy of the full BCS Summary Score (area under the curve [AUC] = 0.857) was comparable to the MMSE (AUC = 0.828). However, a reduced BCS Summary Score consisting of OTMT Part B (OTMT,B), animal fluency, and the CDT yielded classification accuracy (AUC = 0.946) that was superior to the MMSE. Conclusions:, Preliminary findings suggest the BCS is an effective, convenient alternative cognitive screening instrument for use in emergent psychiatric populations. ACADEMIC EMERGENCY MEDICINE 2010; 17:307,315 © 2010 by the Society for Academic Emergency Medicine [source] Utility of the distal compound muscle action potential duration for diagnosis of demyelinating neuropathiesJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 3 2009Sagiri Isose Abstract To assess the significance of distal compound muscle action potential (CMAP) duration for diagnosis of demyelinating neuropathies, electrophysiologic data were reviewed from 471 subjects, including 145 normal controls, 60 patients with chronic inflammatory demyelinating polyneuropathy (CIDP), 205 with other neuropathy, and 61 with amyotrophic lateral sclerosis (ALS). The duration of distally evoked CMAP was measured in the median, ulnar, tibial, and peroneal nerves. Optimal cut-off values were calculated with receiver-operating characteristic (ROC) curves. In comparison of normal controls and CIDP patients, ROC analyses showed the sufficient area under the curves (82-93%). When the cut-off values in the detection of demyelination were determined as the point with 98% specificity vs. normal on the ROC curves (median, 6.6 ms; ulnar, 6.7 ms; peroneal, 7.6 ms; tibial, 8.8 ms), the sensitivity was 77% for CIDP, with a specificity of 90% vs. ALS and 95% vs. diabetic neuropathy. The distal CMAP duration is a useful index for the detection of distal demyelination. We suggest the above cut-off values for each nerve as one of the electrodiagnostic criteria for demyelinating neuropathies, preferentially affecting the distal nerve terminals, such as CIDP. [source] Clinical prediction rule to diagnose post-infectious bronchiolitis obliterans in childrenPEDIATRIC PULMONOLOGY, Issue 11 2009Alejandro J. Colom Abstract Rationale Infant pulmonary function testing has a great value in the diagnosis of post-infectious bronchiolitis obliterans (BOs), because of characteristic patterns of severe and fixed airway obstruction. Unfortunately, infant pulmonary function testing is not available in most pediatric pulmonary centers. Objective To develop and validate a clinical prediction rule (BO-Score) to diagnose children under 2 years of age with BOs, using multiple objectively measured parameters readily available in most medical centers. Methods Study subjects, children under 2 years old with a chronic pulmonary disease assisted at R. Gutierrez Children's Hospital of Buenos Aires. Patients were randomly divided into a derivation (66%) and a validation (34%) set. ROC analyses and multivariable logistic regression included significant clinical, radiological, and laboratory predictors. The main outcome measure was a diagnosis of BOs. The performance of the BO-Score was tested on the validation set. Results Hundred twenty-five patients were included, 83 in the derivation set and 42 in the validation set. The BO-Score (area under ROC curve,=,0.96; 95% CI, 0.9,1.0%) was developed by assigning points to the following variables: typical clinical history (four points), adenovirus infection (three points), and high-resolution computed tomography with mosaic perfusion (four points). A Score ,7 predicted the diagnosis of BOs with a specificity of 100% (95% CI, 79,100%) and a sensitivity of 67% (95% CI, 47,80%). Conclusions The BO-Score is a simple-to-use clinical prediction rule, based on variables that are readily available. A BO-Score of 7 or more predicts a diagnosis of post-infectious BOs with high accuracy. Pediatr Pulmonol. 2009; 44:1065,1069. ©2009 Wiley-Liss, Inc. [source] Relative clinical utility of three child symptom inventory-4 scoring algorithms for differentiating children with autism spectrum disorder vs. attention-deficit hyperactivity disorderAUTISM RESEARCH, Issue 6 2009Carla J. DeVincent Abstract Objective: The present study compared three separate Child Symptom Inventory-4 (CSI-4) scoring algorithms for differentiating children with autism spectrum disorder (ASD) from youngsters with attention-deficit/hyperactivity disorder (ADHD). Method: Parents/teachers completed the CSI-4, a DSM-IV-referenced rating scale, for 6 to 12-year-old clinical referrals with ASD (N=186) and ADHD (N=251). Algorithms were based on either all CSI-4 items (forward logistic regressions) or the 12 DSM-IV symptoms of pervasive developmental disorder (PDD) included in the CSI-4. Results: ROC analyses indicated generally good to excellent values for area under the curve, sensitivity, specificity, and positive predictive power. Algorithms for parent ratings were superior to teacher ratings. The algorithm based solely on PDD symptoms evidenced the greatest generalizability. Conclusion: Although algorithms generated from regression analyses produced greater clinical utility for specific samples, the PDD-based algorithm resulted in greater stability across samples. [source] Predicting the outcome of prostate biopsy: comparison of a novel logistic regression-based model, the prostate cancer risk calculator, and prostate-specific antigen level aloneBJU INTERNATIONAL, Issue 5 2009David J. Hernandez OBJECTIVES To develop a logistic regression-based model to predict prostate cancer biopsy at, and compare its performance to the risk calculator developed by the Prostate Cancer Prevention Trial (PCPT), which was based on age, race, prostate-specific antigen (PSA) level, a digital rectal examination (DRE), family history, and history of a previous negative biopsy, and to PSA level alone. PATIENTS AND METHODS We retrospectively analysed the data of 1280 men who had a biopsy while enrolled in a prospective, multicentre clinical trial. Of these, 1108 had all relevant clinical and pathological data available, and no previous diagnosis of prostate cancer. Using the PCPT risk calculator, we calculated the risks of prostate cancer and of high-grade disease (Gleason score ,7) for each man. Receiver operating characteristic (ROC) curves for the risk calculator, PSA level and the novel regression-based model were compared. RESULTS Prostate cancer was detected in 394 (35.6%) men, and 155 (14.0%) had Gleason ,7 disease. For cancer prediction, the area under the ROC curve (AUC) for the risk calculator was 66.7%, statistically greater than the AUC for PSA level of 61.9% (P < 0.001). For predicting high-grade disease, the AUCs were 74.1% and 70.7% for the risk calculator and PSA level, respectively (P = 0.024). The AUCs increased to 71.2% (P < 0.001) and 78.7% (P = 0.001) for detection and high-grade disease, respectively, with our novel regression-based models. CONCLUSIONS ROC analyses show that the PCPT risk calculator modestly improves the performance of PSA level alone in predicting an individual's risk of prostate cancer or high-grade disease on biopsy. This predictive tool might be enhanced by including percentage free PSA and the number of biopsy cores. [source] Prediction of glomerular filtration rate in renal transplant recipients: cystatin C or Modification of Diet in Renal Disease equation?CLINICAL TRANSPLANTATION, Issue 2 2006Uwe Pöge Abstract: Background: To overcome disadvantages of serum creatinine two strategies have been suggested to identify patients with reduced glomerular filtration rate (GFR). On the one hand, the Modification of Diet in Renal Disease (MDRD) equation is now recommended to classify the stage of chronic kidney disease. On the other hand, cystatin C (Cys C) has been investigated in numerous studies, finding a higher sensitivity than creatinine in detecting diminished GFR. To date, no comparison of both strategies in patients after renal transplantation has been performed. Methods: One hundred and five consecutive renal transplant recipients underwent 99mTc-DTPA , clearance measurement. Simultaneously, MDRD estimates were calculated and Cys C serum levels were determined. ROC analyses were performed at different decision points from 20 to 70 mL/min/1.73 m2. Results: Although the area under the curve did not differ significantly between MDRD and Cys C within the tested GFR range, the AUC for Cys C tended to be higher when GFR exceeded 55 mL/min/1.73 m2. A significantly higher diagnostic accuracy for Cys C compared with MDRD (p=0.045 at 65 mL/min/1.73 m2) was found when investigating the subgroup of patients with well-functioning grafts (GFR>40 mL/min/1.73 m2). Conclusion: MDRD equation is equivalent to Cys C measurement in renal transplant recipients. As availability of MDRD is superior to Cys C, we recommend GFR estimation using the MDRD equation. Nevertheless, Cys C may serve as a confirmation test of high MDRD estimates in patients with well-functioning grafts because of superior accuracy in these patients. [source] The validity of the Violence Risk Appraisal Guide (VRAG) in predicting criminal recidivismCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 2 2007Carolin Kröner Introduction,The VRAG is an actuarial risk assessment instrument, developed in Canada as an aid to estimating the probability of reoffending by mentally ill offenders. Aim,To test the predictive validity of the VRAG with a German sample. Method,The predictive validity of the VRAG was tested on a sample of 136 people charged with a criminal offence and under evaluation for criminal responsibility in the forensic psychiatry department at the University of Munich in 1994,95. The predicted outcome was tested by means of ROC analysis for correlation with the observed rate of recidivism between discharge after the 1994,95 assessment and the census date of 31 March 2003. Recidivism rate was calculated from the official records of the National Conviction Registry. Results,Just over 38% of the sample had reoffended by 2003. Their mean time-at-risk was 58 months (SD 3.391; range 0,115 months). The VRAG yielded a high predictive accuracy in the ROC analysis with an AUC of 0.703. For a constant time-at-risk < = 7 years, the predicted probability and observed rates of recidivism correlated significantly with Pearson's r = 0.941. Conclusions,The validity of the VRAG was replicated with a German sample. The VRAG yielded good predictive accuracy, despite differences in sample and outcome variables compared with its original sample. Copyright © 2007 John Wiley & Sons, Ltd. [source] Validation of the World Health Organization Alcohol, Smoking and Substance Involvement Screening Test (ASSIST): report of results from the Australian siteDRUG AND ALCOHOL REVIEW, Issue 3 2005DAVID A. L. NEWCOMBE Abstract The concurrent, construct, discriminative and predictive validity of the World Health Organization's Alcohol Substance Involvement Screening Test (ASSIST) were examined in an Australian sample. One hundred and fifty participants, recruited from drug treatment (n = 50) and primary health care (PHC) settings (n = 100), were administered a battery of instruments at baseline and a modified battery at 3 months. Measures included the ASSIST; the Addiction Severity Index-Lite (ASI-Lite); the Severity of Dependence Scale (SDS); the MINI International Neuropsychiatric Interview (MINI-Plus); the Rating of Injection Site Condition (RISC); the Drug Abuse Screening Test (DAST); the Alcohol Use Disorders Identification Test (AUDIT); the Revised Fagerstrom Tolerance Questionnaire (RTQ); and the Maudsely Addiction Profile (MAP). Concurrent validity was demonstrated by significant correlations between ASSIST scores and scores from the ASI-lite, SDS, AUDIT and DAST; and significantly greater ASSIST scores for those with diagnoses of abuse or dependence. Construct validity was established by significant correlations between ASSIST scores and measures of risk factors for the development of drug and alcohol problems. Participants diagnosed with attention deficit/hyperactivity disorder or antisocial personality disorder had significantly higher ASSIST scores than those not diagnosed as such. Discriminative validity was established by the capacity of the ASSIST to discriminate between substance use, abuse and dependence. ROC analysis was able to establish cut-off scores for an Australian sample, with suitable specificities and sensitivities for most substances. Predictive validity was demonstrated by similarity in ASSIST scores obtained at baseline and at follow-up. The findings demonstrated that the ASSIST is a valid screening test for psychoactive substance use in individuals who use a number of substances and have varying degrees of substance use. [source] What changes in health-related quality of life matter to multiple myeloma patients?EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2010A prospective study Abstract Objective: To determine the clinical significance of changes in quality-of-life scores in patients with multiple myeloma (MM), we have estimated the minimal important difference (MID) for the health-related quality-of-life instrument, the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30. The MID is the smallest change in a quality-of-life score considered important to patients. Methods: Between 2006 and 2008, 239 patients with MM completed the EORTC QLQ-C30 at inclusion (T1) and after 3 months (T2). At T2, a structured quality-of-life interview was also performed. MIDs were calculated by using mean score changes (T2,T1) for patients who in the interview stated they had improved, deteriorated or were unchanged. MIDs were also estimated by the receiver-operating characteristic (ROC) curve method as well as by calculation effect sizes using standard deviations of baseline scores. Results: MIDs varied slightly depending on the method used. Patients stating in the interview that they had ,improved' or ,deteriorated' had a corresponding change in EORTC QLQ-C30 score ranging from 6 to15 (improvement) and from 9 to17 (deterioration) (scale range 0,100). The ROC analysis indicated that changes in score from 7 to17 represent clinically important changes to patients. The effect size method suggested 5,6 to be a small and 11,15 to be a medium change. Conclusion: Calculation of MIDs as mean score changes or by ROC analysis suggested that a change in the EORTC QLQ-C30 score in the range of approximately 6,17 is considered important by patients with MM. These MIDs are closer to a medium effect size than to a small effect size. Our findings imply that mean score changes smaller than 6 are unlikely to be important to the patients, even if these changes are statistically significant. [source] Quantitative determination of the diagnostic accuracy of the synovitis score and its componentsHISTOPATHOLOGY, Issue 3 2010Elisabeth Slansky Slansky E, Li J, Häupl T, Morawietz L, Krenn V & Pessler F (2010) Histopathology,57, 436,443 Quantitative determination of the diagnostic accuracy of the synovitis score and its components Aims:, To assess the diagnostic accuracy of a three-component synovitis score and to determine the relative contribution of each of its components to its overall discriminatory power. Methods and results:, The synovitis score was determined in 666 synovial specimens: normal synovium, n = 33; post-traumatic arthropathy (PtA), n = 29; osteoarthritis (OA), n = 221; psoriatic arthritis (PsA), n = 42; and rheumatoid arthritis (RA), n = 341. The discriminatory abilities of the score and its components were quantified with binary and multicategory receiver operating characteristic (ROC) analysis. The score differentiated all arthropathies accurately from normal tissue (area under the ROC curve, AUC: 0.87,0.98) and RA from OA or PtA (AUC: 0.85 for both), but could not distinguish well within pairs of inflammatory or degenerative arthropathies. AUCs of the intimal hyperplasia and stromal cellularity components correlated with the AUCs of the complete score markedly more strongly (r = 0.94 and 0.91, respectively) than the inflammatory infiltration component (r = 0.60). Multicategory ROC analysis ranked the score several-fold higher than any of its components, and the components in the order stromal cellularity>intimal hyperplasia>infiltration. Conclusion:, Combining three distinct histological parameters into a three-component score produces greatly increased overall diagnostic power. The discriminatory ability of the score stems more from measuring proliferative than infiltrative aspects of synovitis. [source] Enhanced formation of advanced oxidation protein products in IBDINFLAMMATORY BOWEL DISEASES, Issue 6 2008Malgorzata Krzystek-Korpacka PhD Abstract Background: Advanced oxidation protein products (AOPPs) are new protein markers of oxidative stress with pro-inflammatory properties, accumulated in many pathological conditions. The issue of their enhanced formation in IBD has not been addressed yet. Methods: The concentration of relative AOPPs (rAOPP; concentration of AOPPs divided by albumin level) were measured in 68 subjects with ulcerative colitis (UC), 50 subjects with Crohn's disease (CD) and 45 healthy volunteers, and related to disease phenotype, clinical and biochemical activity, and therapeutic strategy. Diagnostic utility of rAOPP was evaluated by ROC analysis. Results: In comparison with controls (1.367 ,mol/g), rAOPP were increased in inactive (1.778 ,mol/g, P = 0.053) and active (1.895 ,mol/g, P = 0.013) UC and in active (1.847 ,mol/g, P = 0.003) CD. In CD, but not UC, rAOPP correlated with disease activity (r = 0.42, P = 0.013). Significant correlations with the inflammatory/malnutrition indices-erythrocyte sedimentation rate (ESR) (r = 0.53), leukocytes (r = 0.33), platelets (r = 0.38), IL-6 (r = 0.36), and transferrin (r = ,0.35) were demonstrated in CD. In UC, rAOPP correlated only with ESR (r = 0.35) and IL-6 (r = 0.30). Instead, associations with antioxidant dismutase (r = 0.29) and catalase (r = 0.22) were observed. The diagnostic power of rAOPP in discriminating diseased from non-diseased subjects was less than that of C-reactive protein (CRP). Simultaneous determination of rAOPP and CRP did not significantly improve the power of single CRP determination. Conclusions: IBD was associated with enhanced formation of AOPP, which differed between C and UC with respect to the relationship between rAOPP and disease activity, inflammatory and antioxidant response. These differences may reflect divergent ways that oxidative stress develops in CD and UC. The diagnostic power of rAOPP was insufficient for its clinical application. (Inflamm Bowel Dis 2008) [source] Automated detection of malaria by means of the haematology analyser Coulter® GEN.STMINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 6 2004C. FOURCADE Summary The haematology analysers Coulter® GEN.STM and LHTM give a set of data ,,positional parameters', which define each WBC population by mean of index values, the mean and the standard deviation (SD) of volume, conductivity and scatter, used to identify the WBC populations. These parameters were analysed in patients investigated for suspicion of malaria, in order to show a difference between malaria negative and malaria positive patients and to use it for malaria detection. The six parameters exhibiting a significant difference between the two groups were submitted to a ROC analysis, which showed both sensitivity >90% and specificity >60% for two parameters, lymphocyte and monocyte SDs of volumes. A discriminator combining the two parameters showed a sensitivity of 96.9% and a specificity of 82.5%. The cut off of the discriminative value was calculated. Because of the good stability and reproducibility of the parameters selected, the test can be used in order to detect patients having a high probability to be malaria positive and to pay particular attention to these blood smears. For more extensive diagnostic use, a standard control procedure of the positional parameters should be introduced. [source] Diagnostic performance of the variant lymphocyte flag of the Abbott Cell-Dyn 4000 haematology analyserINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2004J. J. M. L. Hoffmann Summary Background: In addition to differential cell counts, modern haematology analysers generate suspect flags if abnormal cells are detected. Reports on validation of suspect flags are scarce. We have routine experience with the Abbott Cell-Dyn 4000 analyser for over 5 years and have previously demonstrated the utility of the blast flag. Here we report a similar study on the performance of the analyser's Variant Lymphocyte (VL) flag. Aim of the study: Evaluation of the diagnostic performance of the Cell-Dyn 4000 VL flag, as compared with lymphocyte morphology in blood smears. In addition, we investigated the usefulness of the numerical VL flag confidence index as provided by the analyser. Materials and methods: All samples generating a VL flag were reviewed over a 5-month period. We also reviewed smears from patients with known lymphoid disorders, even if the analyser did not flag the sample. Two experienced investigators assessed lymphocyte morphology independently. Results: In total, 187 samples were included in the study, of which 183 had a VL flag and four had not. Of the 183 flagged samples, 83 appeared to have abnormal lymphocyte morphology and 100, normal lymphocyte morphology. The sensitivity of the VL flag for detecting abnormal lymphocytes was 0.95 and the positive predictive value was 0.44. Using ROC analysis of the VL flag confidence index, the area under the ROC curve was 0.58 (95% confidence interval 0.50,0.65). Conclusions: The Cell-Dyn VL flag has reasonable sensitivity but a high false-positive rate. In addition, its performance is insufficient for detecting clinically relevant abnormal lymphocytes. As the VL flag appeared to rely mainly on numerical criteria, it has no added value over numerical criteria defined by the laboratory. [source] Screening for mental disorders in cancer patients , discriminant validity of HADS and GHQ-12 assessed by standardized clinical interviewINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2001Katrin Reuter Abstract The detection and classification of comorbid mental disorders has major implications in cancer care. Valid screening instruments for different diagnostic specifications are therefore needed. This study investigated the discriminant validity of the German versions of the Hospital Anxiety and Depression Scale (HADS) and the General Health Questionnaire (GHQ-12). A total of 188 cancer patients participated in the examination, consisting first of the assessment of psychological distress and, second, of the diagnosis of mental disorders according to DSM-IV by clinical standardized interview (CIDI). Discriminant validity of the two instruments regarding the diagnosis of any mental disorder, anxiety, depression and multiple mental disorders was compared using ROC analysis. Overall, the total HADS scale shows a better screening performance than the GHQ-12, especially for the detection of depressive and anxiety disorders. Best results are achieved for depressive disorders with an area under the curve (AUC) of 0.80, a sensitivity of 79% and a specificity of 76% (cut-off point = 17). For the ability of the instruments to detect patients with mental disorders in general, the GHQ-12 (AUC: 0.68) shows a similar overall accuracy to the HADS (AUC: 0.70). The screening performance of both scales for comorbid mental disorders is comparable. The HADS is a valid screening instrument for depressive and anxiety disorders in cancer care. The GHQ-12 can be considered as an alternative to the HADS when diagnostic specifications are less detailed and the goal of screening procedures is to detect patients with single or multiple mental disorders in general. Limitations of conventional screening instruments are given through the differing methodological approaches of screening tests (dimensional approach) and diagnosis according to DSM-IV (categorical approach). Copyright © 2001 Whurr Publishers Ltd. [source] Recommended dietary allowance for vitamin C in the United States is also applicable to a population of young Japanese womenJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 6 2004Hiroshi Ihara Abstract The recommended dietary allowance (RDA) for ascorbic acid (AA) in Canada and the United States has been set for several years at 75 mg/day for women 19,30 years old. Recently this level was questioned, and an increase to 90 mg/day was suggested. For Japanese women in the same age group, we found that the RDA for AA is currently 100 mg/day. Our goal was to determine which RDA is sufficient for maintaining a serum concentration of AA in young Japanese women above the lower reference limit of 7.0 mg/L. We measured serum AA concentrations by an ascorbate oxidase method in 176 healthy Japanese women (19,26 years old). We also performed an ROC analysis to estimate the optimal cutoff value for oral dosage to distinguish individuals with hypovitaminosis-C (<7.0 mg/L) from those with a normal serum AA. We evaluated the Japanese RDA using the 75 or 90 mg/day U.S. RDA and the weight ratio between Japanese and U.S. women, and discovered that the RDA value ranged between 66 and 79 mg/day. From the ROC analysis, we found that the optimal daily dosage of AA is approximately 75 mg/day. This value gave the highest efficiency, sensitivity, negative predictive value, and positive likelihood ratio, and the lowest negative likelihood ratio. Therefore, an RDA of 100 mg/day may be unnecessarily high for young Japanese women. J. Clin. Lab. Anal. 18:305,308, 2004. © 2004 Wiley-Liss, Inc. [source] Differentiation of intraductal papillary mucinous neoplasms from other pancreatic cystic masses: Comparison of multirow-detector CT and MR imaging using ROC analysisJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2007Su Jin Song MD Abstract Purpose To compare the diagnostic performance of multirow-detector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the differentiation of intraductal papillary mucinous neoplasms (IPMNs) from other pancreatic cystic masses. Materials and Methods A total of 53 patients with pathologically proven pancreatic cystic lesions who had undergone MDCT and MRI were included in this study. Two radiologists analyzed the morphologic features of the lesions and graded the lesion conspicuity on each examination. The readers assigned their confidence level regarding the differentiation of IPMN from other lesions and predicting ductal communication of the lesion. The radiologists' diagnostic confidence was compared using receiver operating characteristic (ROC) analysis. Results The Az values for each observer for predicting ductal communication of the lesion and differentiating IPMN from other lesions were as follows: For MRI they were respectively 0.949 and 0.995 for reader 1, and 0.916 and 0.932 for reader 2. For MDCT they were respectively 0.790 and 0.875 for reader 1, and 0.774 and 0.850 for reader 2. In addition, for differentiating IPMNs from other lesions, MRI was significantly more accurate than MDCT (P < 0.05) for one observer, but for the other observer there was no significant difference between the two examinations (P = 0.059). For predicting ductal communication of the cystic lesions for both observers, MRI was significantly more accurate than MDCT (P < 0.05). The weighted , values indicate good agreement (, = 0.61) between observers for MDCT, and excellent agreement (, = 0.82) for MRI. Conclusion Pancreatic MRI shows better diagnostic performance than MDCT for differentiating IPMNs from other cystic lesions of the pancreas. J. Magn. Reson. Imaging 2007;26:86,93. © 2007 Wiley-Liss, Inc. [source] AgNOR count as objective marker for dysplastic features in oral leukoplakiaJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 9 2002Amit Chattopadhyay Abstract Background:,, Dysplasia is an important feature of leukoplakia. Because agreement among oral pathologists is poor regarding lesional diagnosis, silver stainable nucleolar organizer regions (AgNORs) as replicatory markers may have a place in objectively characterizing dysplasia in tissue specimens. Methods:,, We studied 41 normal oral epithelia, 51 oral leukoplakia (26 dysplastic, 25 non-dysplastic), and 51 cases of squamous cell carcinoma specimens for their mean AgNOR counts. Results:,, Mean AgNOR counts increased gradually from normal epithelium to non-dysplastic to dysplastic leukoplakia to squamous cell carcinoma. Using ROC analysis, we determined a mean AgNOR count cut-point (2.37) that can be used to distinguish between dysplastic and non-dysplastic leukoplakia. The test had a sensitivity of 75% and specificity of 83% with area under the curve being 88%. Conclusions:, Mean AgNOR count could be a valuable criterion for defining objective parameters for diagnosis/determination of dysplasia distinguishing between dysplastic and non-dysplastic leukoplakia. [source] Development of the GerdQ, a tool for the diagnosis and management of gastro-oesophageal reflux disease in primary careALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2009R. JONES Summary Background, Accurate diagnosis and effective management of gastro-oesophageal reflux disease (GERD) can be challenging for clinicians and other health care professionals. Aim, To develop a patient-centred, self-assessment questionnaire to assist health care professionals in the diagnosis and effective management of patients with GERD. Methods, Questions from patient-reported GERD instruments, previously documented in terms of content validity and psychometric properties (RDQ, GSRS and GIS) and data on the diagnosis of GERD in primary and secondary care were used in the formal development of a diagnostic and management tool, the GerdQ, involving psychometric validation and piloting in patient focus groups. Results, Analyses of data from over 300 primary care patients, moderated by patient input from qualitative interviews, were used to select specific items from the existing instruments to create a new six-item diagnostic and management tool (GerdQ). ROC analysis indicated a sensitivity for GerdQ of 65% and a specificity of 71% for the diagnosis of GERD, similar to that achieved by gastroenterologists. Conclusion, The GerdQ is a potentially useful tool for family practitioners and other health care professionals in diagnosing and managing GERD without initial specialist referral or endoscopy. [source] Sputum eosinophilia: an early marker of bronchial response to occupational agentsALLERGY, Issue 5 2009O. Vandenplas Background:, False-negative responses to specific inhalation challenge (SIC) with occupational agents may occur. We explored whether assessing changes in sputum cell counts would help improve the identification of bronchial reactivity to occupational agents during SICs. Methods:, The predictive value of the changes in sputum cell counts after a negative FEV1 response to a first challenge exposure to an occupational agent was determined using the changes in airway calibre observed during repeated challenges as the ,gold standard'. The study included 68 subjects investigated for work-related asthma in a tertiary centre. After a control day, the subjects were challenged with the suspected occupational agent(s) for up to 2 h. All subjects who did not show an asthmatic reaction were re-challenged on the following day. Additional challenges were proposed to those who demonstrated a , 2% increase in sputum eosinophils or an increase in nonspecific bronchial hyperresponsiveness to histamine after the second challenge day. Results:, Six of the 35 subjects without changes in FEV1 on the first challenge developed an asthmatic reaction on subsequent challenges. ROC analysis revealed that a >3% increase in sputum eosinophils at the end of the first challenge day was the most accurate parameter for predicting the development of an asthmatic response on subsequent challenges with a sensitivity of 67% and a specificity of 97%. Conclusions:, An increase in sputum eosinophils is an early marker of specific bronchial reactivity to occupational agents, which may help to identify subjects who will develop an asthmatic reaction only after repeated exposure. [source] Evaluation of erythrocyte dysmorphism by light microscopy with lowering of the condenser lens: A simple and efficient methodNEPHROLOGY, Issue 2 2010GYL EANES BARROS SILVA ABSTRACT: Aim: To demonstrate that the evaluation of erythrocyte dysmorphism by light microscopy with lowering of the condenser lens (LMLC) is useful to identify patients with a haematuria of glomerular or non-glomerular origin. Methods: A comparative double-blind study between phase contrast microscopy (PCM) and LMLC is reported to evaluate the efficacy of these techniques. Urine samples of 39 patients followed up for 9 months were analyzed, and classified as glomerular and non-glomerular haematuria. The different microscopic techniques were compared using receiver,operator curve (ROC) analysis and area under curve (AUC). Reproducibility was assessed by coefficient of variation (CV). Results: Specific cut-offs were set for each method according to their best rate of specificity and sensitivity as follows: 30% for phase contrast microscopy and 40% for standard LMLC, reaching in the first method the rate of 95% and 100% of sensitivity and specificity, respectively, and in the second method the rate of 90% and 100% of sensitivity and specificity, respectively. In ROC analysis, AUC for PCM was 0.99 and AUC for LMLC was 0.96. The CV was very similar in glomerular haematuria group for PCM (35%) and LMLC (35.3%). Conclusion: LMLC proved to be effective in contributing to the direction of investigation of haematuria, toward the nephrological or urological side. This method can substitute PCM when this equipment is not available. [source] Heart Rate Turbulence Impairment and Ventricular Arrhythmias in Patients with Systemic SclerosisPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2010PIOTR BIENIAS M.D., Ph.D. Background:,Arrhythmias, conduction disturbances, and cardiac autonomic nervous system dysfunction are the most frequent cardiovascular complications in systemic sclerosis (scleroderma). The aim of the study was to assess heart rate turbulence (HRT) in systemic sclerosis patients and to identify the relationship between HRT and occurrence of arrhythmias. Methods:,Forty-five patients with scleroderma (aged 54.6 ± 14.7 years) and 30 healthy sex- and age-matched subjects were examined. In addition to routine studies, 24-hour Holter monitoring with assessment of HRT was performed. Results:,As compared to controls, HRT was significantly impaired in systemic sclerosis patients. Abnormal HRT defined as turbulence onset (TO) ,0.0% and/or turbulence slope (TS) ,2.5 ms/RR (ms/RR interval) was found in 19 (42%) scleroderma patients and in no members of the control group. Serious ventricular arrhythmias Lown class IV (VA-LownIV), for example, couplets and/or nonsustained ventricular tachycardias, were observed in 16 (36%) scleroderma patients. The median value of TS was significantly lower in systemic sclerosis patients with VA-LownIV than in patients without VA-LownIV (3.68 vs 7.00 ms/RR, P = 0.02). The area under curve of ROC analysis for prediction of VA-LownIV was 0.72 (95% confidence interval [CI] 0.56,0.87) and revealed that TS <9.0 ms/RR was associated with VA-Lown IV occurrence, with sensitivity of 93.7% and specificity of 44.8%. Univariate and multivariate analyses confirmed that lower values of TS were associated with VA-LownIV occurrence (odds ratio 1.52, 95% CI 1.09,2.12, P = 0.01). Conclusions:,Patients with systemic sclerosis are characterized by significant HRT impairment. Assessment of HRT and especially TS is useful in the identification of patients at risk for ventricular arrhythmias. (PACE 2010; 920,928) [source] Asthma Control Test correlates well with the treatment decisions made by asthma specialistsRESPIROLOGY, Issue 4 2009Fanny W.S. KO ABSTRACT Background and objective: Poor assessment of asthma control results in suboptimal treatment. Identifying parameters that accurately assess control will benefit treatment decisions. The Asthma Control Test (ACT) is a five-item questionnaire for the assessment of asthma control. This study evaluated its correlation with the treatment decisions made by asthma specialists in an outpatient clinic setting, and compared its performance with other conventional parameters including spirometry, PEF rate (PEFR), fractional exhaled nitric oxide (FeNO) and BHR. Methods: The 383 (122 men) study subjects completed a 1-month diary on symptoms and PEFR before the assessment. All subjects then completed the ACT together with same-day spirometry and FeNO measurement. BHR to methacholine was performed in 73 subjects in the week before assessment. Asthma specialists, blinded to the results of the ACT, FeNO and BHR (but not spirometry and PEFR), assessed the patients' level of control according to the 2006 version of the Global Initiative for Asthma guidelines and made appropriate treatment decision. Results: The group mean (SD) age was 46.1 (13.4) years with pre-bronchodilator FEV1 84.72 (20.81) % predicted. Receiver operating characteristic (ROC) curve analysis found that an ACT score of ,20 best correlated with uncontrolled asthma (area under curve (AUC) = 0.76) with a sensitivity of 70.5%, specificity 76.0%, positive predictive value 76.2% and negative predictive value 70.2% for predicting step-up of asthma therapy. On ROC analysis, the ACT score had the highest AUC (0.81 (P < 0.001)) for changing asthma therapy when compared with FeNO, spirometry, PEFR and BHR parameters Conclusions: The ACT correlated better with treatment decisions made by asthma specialists than spirometry, PEFR and FeNO. [source] ORIGINAL RESEARCH,OUTCOMES ASSESSMENT: Validation of the Female Sexual Distress Scale-Revised for Assessing Distress in Women with Hypoactive Sexual Desire DisorderTHE JOURNAL OF SEXUAL MEDICINE, Issue 2 2008Leonard DeRogatis PhD ABSTRACT Introduction., The concept of sexually related personal distress is currently central to the diagnosis of all female sexual dysfunctions (FSD). In the current study, we have focused on validating a slightly revised version of the Female Sexual Distress Scale (FSDS), the FSDS-Revised (FSDS-R), to enhance the sensitivity of the instrument with patients suffering from hypoactive sexual desire disorder (HSDD). In addition, we have attempted to extend the validation generalizability of the scale by demonstrating that both instruments possess reliability and discriminative validity in premenopausal women with HSDD. Aim., To assess the validity of the revised version of the FSDS, the FSDS-R, for measuring sexual distress in women with HSDD. Methods., A prospective methodological study carried out at 27 centers in North America enrolled 296 women aged 18,50 years with HSDD, another female sexual dysfunction (FSD), or no FSD. The subjects completed the FSDS-R at baseline, day 7, and day 28, with a 30-day recall at baseline and with a 7-day recall on days 7 and 28. Main Outcome Measures., Receiver operating characteristic (ROC) analyses of FSDS, FSDS-R, and FSDS-R item 13 were used for the differentiation of HSDD from no FSD, while intraclass correlation coefficient (ICC) was used to estimate test,retest reliability. Cronbach's coefficient alpha was used to measure the internal consistency of the FSDS-R and Pearson's correlation coefficient to assess FSDS, FSDS-R, and FSDS-R item 13 with different recall periods (7 and 30 days). Results., Mean total FSDS, FSDS-R, and FSDS-R item 13 scores with either recall period were significantly higher (P < 0.0001) in women with FSD or HSDD than in women with no FSD, showing both tests had discriminant validity. ROC analysis confirmed these findings, while an ICC of >0.74 showed the test,retest reliability of both scales, including FSDS-R item 13 alone, and Cronbach's coefficient alpha of >0.86 confirmed the internal consistency of both tests. Conclusions., Consistent with the FSDS, the FSDS-R demonstrated good discriminant validity, high test,retest reliability, and a high degree of internal consistency in measuring sexually related personal distress in women with HSDD. FSDS-R item 13 alone also demonstrated good discriminant validity and test,retest reliability. DeRogatis L, Clayton A, Lewis-D'Agostino D, Wunderlich G, and Fu Y. Validation of the female sexual distress scale revised for assessing distress in women with hypoactive sexual desire disorder. J Sex Med 2008;5:357,364. [source] Phonation threshold flow measurements in normal and pathological phonationTHE LARYNGOSCOPE, Issue 4 2009Peiyun Zhuang MD Abstract Objectives/Hypothesis: Phonation threshold flow (PTF) may provide a tool to assess laryngeal function and could differentiate between normal and pathological voices. Both polyps and nodules contribute to an increased PTF by creating an incomplete glottal closure and increased vocal fold mass and thickness. Study Design: Prospective study. Methods: The Kay Elemetrics Phonatory Aerodynamic System (PAS) (Kay Elemetrics Corp., Lincoln Park, NJ) was used to collect mean flow rate (MFR) and PTF measurements from 40 normal subjects, 21 patients with vocal fold nodules, and 23 patients with vocal fold polyps. Gender-based differences were assessed using a t test. The effect of vocal pathology on PTF and MFR was determined with an ANOVA. Diagnostic potential was evaluated using a receiver operation characteristics (ROC) analysis. Results: Both PTF (P = .047) and MFR (P = .008) were significantly affected by gender. Using a two-way ANOVA and correcting for gender differences, the influence of pathology on PTF was determined to be significant (P < .001). Post hoc tests found a significant difference between normal and polyp subjects (P < .001) but not normal and nodule subjects (P = .177) or nodule and polyp subjects (P = .246). ROC analysis found that PTF (area under the curve [AUC] = 0.691) and MFR (AUC = 0.684) had a similar diagnostic utility. Conclusions: PTF can be used to differentiate between normal and pathological voices. As a parameter that is experimentally sensitive to the biomechanical parameters providing its theoretical basis, it could be used clinically to analyze laryngeal functionality. Future research could focus on measuring PTF in other pathologies, such as paralysis or scarring, which would also affect the effort required to produce voice. Laryngoscope, 2009 [source] Significance of Des-Gamma-Carboxy Prothrombin in Selection Criteria for Living Donor Liver Transplantation for Hepatocellular CarcinomaAMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2009M. Fujiki Des-gamma-carboxy prothrombin (DCP) levels reportedly correlate with histological features of hepatocellular carcinoma (HCC). We examined serum DCP as a predictor of HCC recurrence in 144 patients who underwent living donor liver transplantation. Receiver operating characteristics (ROC) analysis revealed superiority of DCP and AFP over preoperative tumor size or number for predicting recurrence. Multivariate analysis revealed tumor size >5 cm, ,11 nodules, and DCP >400 mAU/mL as significant independent risk factors for recurrence. Incidence of microvascular invasion (62% vs. 27%, p = 0.0003) and poor differentiation (38% vs. 16%, p = 0.0087) were significantly higher for patients with DCP >400 mAU/mL than for patients with DCP ,400 mAU/mL. In ROC analysis for patients with ,10 nodules all ,5 cm to predict recurrence, area under the curve was much higher for DCP than for AFP (0.84 vs. 0.69). Kyoto criteria were thus defined as ,10 nodules all ,5 cm, and DCP ,400 mAU/mL. The 5-year recurrence rate for 28 patients beyond-Milan but within-Kyoto criteria was as excellent as that for 78 patients within-Milan criteria (3% vs. 7%). The preoperative DCP level offers additional information regarding histological features, and thus can greatly improve patient selection criteria when used with tumor bulk information. [source] Coronary Flow Reserve by Contrast-Enhanced Echocardiography: A New Noninvasive Diagnostic Tool for Cardiac Allograft VasculopathyAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5p1 2006F. Tona Noninvasive tests have proven unsatisfactory in cardiac allograft vasculopathy (CAV) diagnosis. We assessed coronary flow reserve (CFR) by contrast-enhanced transthoracic echocardiography (CE-TTE) in heart transplantation (HT). CFR was assessed in the left anterior descending coronary artery in 73 HT recipients (59 male, aged 50 ± 12 years at HT), at 8 ± 4.5 years post-HT. CFR measurements were taken blindly from coronary angiographies. CFR cut points were the standard value of ,2 and those defined by receiver operating characteristics (ROC) curve analysis. CFR was lower in patients with CAV (2.3 ± 0.7 vs. 3.2 ± 0.5, p < 0.0001). The ,2 cut point was 100% specific and 38% sensitive. The ,2.7 cut point, optimal by ROC analysis, was 87% specific and 82% sensitive. Accuracy rose from 71% with the standard ,2 cut point to 85% with the optimal cut point of ,2.7. CFR by CE-TTE may offer promise as a novel, easily repeatable and accurate noninvasive tool in CAV detection. However, further longitudinal studies in larger patient cohorts are warranted before widespread adoption can be advocated. [source] Ethnicity affects the diagnostic validity of alpha-fetoprotein in hepatocellular carcinomaASIA-PACIFIC JOURNAL OF CLINICAL ONCOLOGY, Issue 2-3 2005Amal GAD Abstract Introduction: Hepatocellular carcinoma (HCC) is the fourth most common cancer worldwide with a high morbidity and mortality. Alpha-fetoprotein (AFP) is considered the main tumor marker for HCC diagnosis, but the variation in its diagnostic validity among studies justifies further investigation of the underlying contributing factors. Ethnic difference could be one of the factors that has not been well studied. We aimed at investigating the ethnic difference in AFP validity between Egyptian (representing Arabic North African) and Japanese (representing Asian) for HCC diagnosis. Methods: Four cohorts with chronic liver diseases (CLD) were studied: 171 Egyptian (65 HCC/106 non-HCC), and 173 Japanese (45 HCC/128 non-HCC). Laboratory tests including serum AFP, protein-induced vitamin K deficiency or absence (PIVKA-II), alanine aminotransferase (ALT), total bilirubin, platelet count, HBsAg, anti-HCV, and HCV core antigen were conducted using standard commercially available assays. Results: A significantly higher sensitivity of AFP in Egyptian in comparison with Japanese for HCC diagnosis (99 vs 67%, P < 0.001) was observed using an AFP cut-off point of 10 ng/mL, with a comparable specificity, (75,vs, 82%), While, a, sensitivity, of, 98, versus, 56%,,P < 0.001, and, a, specificity, of, 83, versus, 89% was found for AFP cut-off point of 20 ng/mL, respectively. The area under the receiver operating characteristic curve (ROC) was found to be 0.98 (95%CI = 0.969,0.997) for Egyptian and 0.77 (95%CI = 0.686,0.864) for Japanese. The highest sensitivity for the former group occurred at AFP = 20.5 ng/mL and at AFP = 10.2 ng/mL for the latter. Univariate analysis showed no effect for age, sex, underlying liver disease, cirrhosis, Child's class or tumor characteristics (size, pathological grade) on AFP sensitivity, while race significantly contributed to the higher sensitivity among Egyptians in comparison with the Japanese. Using ROC analysis, the AFP cut-off point for HCC detection in each subgroup of patients with and without each of the risk factors of interest was determined and the subgroups were again subclassified according to AFP positivity (< or , the decided cut-off point for each group). Logistic regression analysis of those factors combined showed that Egyptian ethnicity with an AFP level >20.5 ng/mL (P = 0.007), older age (>50 years) with an AFP level >26 ng/mL (P = 0.010), and cirrhosis with an AFP level >10.5 ng/mL (P = 0.014) were the independent risk factors for HCC. Conclusion: There is an ethnic variation in AFP validity between Egyptian and Japanese patients with a significantly lower sensitivity in the latter. Alpha-fetoprotein should not be the only marker used for screening HCC among Asian Japanese and younger age groups (<50 years) with CLD. In addition, an AFP cut-off point of 20 ng/mL is recommended when screening patients of Asian origin for HCC. [source] Area under the Free-Response ROC Curve (FROC) and a Related Summary IndexBIOMETRICS, Issue 1 2009Andriy I. Bandos Summary Free-response assessment of diagnostic systems continues to gain acceptance in areas related to the detection, localization, and classification of one or more "abnormalities" within a subject. A free-response receiver operating characteristic (FROC) curve is a tool for characterizing the performance of a free-response system at all decision thresholds simultaneously. Although the importance of a single index summarizing the entire curve over all decision thresholds is well recognized in ROC analysis (e.g., area under the ROC curve), currently there is no widely accepted summary of a system being evaluated under the FROC paradigm. In this article, we propose a new index of the free-response performance at all decision thresholds simultaneously, and develop a nonparametric method for its analysis. Algebraically, the proposed summary index is the area under the empirical FROC curve penalized for the number of erroneous marks, rewarded for the fraction of detected abnormalities, and adjusted for the effect of the target size (or "acceptance radius"). Geometrically, the proposed index can be interpreted as a measure of average performance superiority over an artificial "guessing" free-response process and it represents an analogy to the area between the ROC curve and the "guessing" or diagonal line. We derive the ideal bootstrap estimator of the variance, which can be used for a resampling-free construction of asymptotic bootstrap confidence intervals and for sample size estimation using standard expressions. The proposed procedure is free from any parametric assumptions and does not require an assumption of independence of observations within a subject. We provide an example with a dataset sampled from a diagnostic imaging study and conduct simulations that demonstrate the appropriateness of the developed procedure for the considered sample sizes and ranges of parameters. [source] | |||||||||||||||||||||||||||||||