Specificity Of Clinical Diagnostics Research Articles

Comparison of diagnostics of bacterial vaginosis according to clinical signs with results of laboratory investigations

Introduction. Bacterial vaginosis (BV) is associated with a number of reproductive health disorders, therefore timely and accurate diagnosis of this condition is exceedingly important. Objective.Comparison of effectiveness of clinical and laboratory diagnostics of BV in women with vaginal discharge. Material and methods. In total, 318 patients addressing gynecological clinics with complaints about vaginal discharge participated in the study. Clinical diagnostics of BV was performed in the clinics participating in patient enrollment in accordance with their clinical practice. For laboratory diagnostics, microscopy of Gram stained smears according to the Nugent method and quantitative real-time PCR were used. Sensitivity and specificity of clinical diagnostics of BV and the molecular method were evaluated using the Nugent method as reference standard. Results. With the Nugent method, BV was diagnosed in 27% of women, with real-time PCR — in 37% of women. Using clinical signs of BV, the condition was diagnosed in 91% women. Sensitivity and specificity of the real-time PCR were 97% and 87%, respectively. Sensitivity of clinical diagnostics was 100%, but specificity was only 17%. Conclusions. Diagnostics of BV based only on the presence of vaginal discharge leads to false positive results and requires laboratory confirmation. The molecular method has a high sensitivity and satisfactory specificity for BV diagnosis and can be used as an alternative to the Nugent method.

An autopsy-based quality assessment program for improvement of diagnostic accuracy.

A program for quality assessment of medical diagnostics is proposed, based on detailed, ongoing comparison of clinical diagnoses with autopsy diagnoses. The model requires that the autopsy service itself be subjected to quality control to assure the reliability of the autopsy findings, including the quality of diagnoses made postmortem, and the quality of autopsy reports. Discrepancies between premortem and postmortem diagnoses are classified as to cause and magnitude; for each disease, the total diagnostic experience is collected, and sensitivity and specificity of clinical diagnostics are computed. These are compared with control ranges of sensitivity and specificity, prospectively arrived at through analysis of thousands of cases. Statistically acceptable sampling for autopsy, and review of findings by an independent body are also discussed. The findings generated by this program would be of great value in programs for quality improvement of medical care. The model has the following advantages: (1) it recognises that there is an unavoidable baseline of diagnostic errors; (2) the control levels, based on current medical practice, are prospectively established; (3) it avoids placing blame in a single case; and (4) it provides a fairly high power scrutiny that can focus on diagnostics for single diseases rather than the entire spectrum of medical practice.

Clinical diagnostic accuracy audited by autopsy in a university hospital in two eras.

A retrospective analysis of 3042 autopsies was carried out to determine and compare the discrepancy rates between clinical and autopsy diagnoses as well as the sensitivity and specificity of clinical diagnostics in 10 diseases in 1977/78 and 1987/88. The autopsy rate decreased from 80% to 39%, which might explain the increased discrepancy rate from 22% to 27% regarding the diagnoses of major, principal diseases. The accuracy of clinical diagnostics seemed to improve during the period for some of the diseases (pulmonary embolism, peptic ulcer, infectious carditis, peritonitis), while it worsened for others (acute myocardial infarction, thrombosis of the mesenteric artery, ruptured aortic aneurysm, tuberculosis) or remained unchanged (cirrhosis of the liver, malignant tumours regarded as a whole group). The findings underline the importance of autopsies and their cumulative studies in assessing the accuracy and providing data for the determination of necessary fallibility of clinical diagnostics.

The autopsy in oncology

The autopsy in oncology

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

To the Editor.— article entitled The Sensitivity and Specificity of Clinical Diagnostics During Five Decades: Toward an Understanding of Necessary Fallibility1fueled a spirited discussion in our journal club. For this I heartily congratulate the authors. article splendidly illustrates some problems with the medical literature. authors introduced an interesting idea that could have been the subject of a brief essay or op-ed, but the idea was presented as a scientific article complete with data and Methods, Results, and Comment sections. result was turgid pseudo-science, posing as meta-analysis, which added nothing to the body of knowledge of science and contributed little to its understanding. studies, directly compared, ranged from autopsy rates of 96% to 23% to unknown; clinical diagnosis ranged from collaboration between clinician and pathologist to (presumably) routine completion of death certificates; the studies span the Atlantic; and no information is given about the

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

<h3>To the Editor.—</h3> The measures of accuracy in clinical screening or diagnosis relate to the intrinsic ability of a procedure to identify correctly those persons with disease (sensitivity) and those persons without disease (specificity).¹In a recent article entitled "The Sensitivity and Specificity of Clinical Diagnostics During Five Decades,"²the authors use the<i>terms clinical accuracy for a positive diagnosis and clinical accuracy for a negative diagnosis</i>and equate them by definition to the positive predictive value (the proportion of positive tests or diagnoses that correctly identify the presence of disease) and the negative predictive value (the proportion of negative tests that correctly identify the absence of disease), respectively. Unlikesensitivity and specificity, the predictive values are not properties inherent to the procedure itself, but vary with the prevalence of disease in the population tested. For example, the authors state that "the accuracy of the clinical diagnosis

Sensitivity, specificity, and predictive values in the 'sensitivity and specificity of clinical diagnostics'

Sensitivity, specificity, and predictive values in the 'sensitivity and specificity of clinical diagnostics'

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

<h3>In Reply.—</h3> Several individuals have called our attention to an unfortunate error in typing that led to publication of an incorrect Table 1. The correct version, as they have all pointed out, is as shown (Table). Drs Woodruff and Baron make an important point in noting that predictive values (which we termed<i>clinical accuracy</i>in an attempt to make it more understandable to those not expert in decision theory) are sensitive to changes in prevalence. As a matter of fact, predictive values were added to the manuscript in response to the suggestion of one of the reviewers, who remarked that their use would be acceptable, so long as they were not going to be directly applied in the screening of other populations. In some of the diseases we studied, there was a marked change inprevalence (as in the case of tuberculosis) that accounted for much of the change in

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

To the Editor.— The article concerning postmortem evaluation of clinical diagnostics during five decades1is a good effort to analyze disparate data that can be resistant to marshaling by ordinary statistical methods. However, I think that the true-negative category, within the constraints of this study, is largely a passive statistic that sheds little light on the diagnostic process. This occurs because the act of making a clinical diagnosis leads to a mutually exclusive binomial distribution of that diagnosis vs a statistical universe of other diagnoses, many of which are trivial. On the other hand, agreed (true positives), underdiagnosed (false negatives), and overdiagnosed (false positives) are intuitively satisfying categories that present a more realistic picture of actual practice. Another statistical method avoids the true-negative dilemma by using only those cells of the fourfold (2 × 2) tables that can be occupied by at least one positive diagnosis (clinical or autopsy).

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

To the Editor.— There was a confusing explanation of sensitivity and specificity in the article by Anderson et al 1 in the March 17 issue. Assuming proper use of the terms true positives, true negatives, false positives , and false negatives , sensitivity and specificity are defined correctly in the Methods section and in the footnote to Table 1. However, it appears that the correct positions of false negatives and false positives were switched in Table 1 (Table). This distinction is important, because if the data for all subsequent tables were analyzed as described in the published Table 1, then what is reported as the sensitivity is actually the predictive value of a positive, and the reported clinical accuracy of a positive diagnosis is actually the sensitivity. A similar switch would also have occurred with the specificity and the clinical accuracy of a negative diagnosis.

The Sensitivity and Specificity of Clinical Diagnostics During Five Decades

Published studies encompassing more than 50,000 autopsies were assessed to determine the sensitivity and specificity of clinical diagnostics (the diagnostic process) in persons dying of 1 of 11 specific diseases during the period 1930 through 1977. The accuracy of clinical diagnostics, as reflected in these two determinations, appeared to improve over this period with respect to some of the diseases studied (rheumatic heart disease and leukemia), while for others it worsened (pulmonary tuberculosis, peritonitis, carcinoma of the lung, gastric carcinoma, and carcinoma of the liver and extrahepatic biliary tract) and for a significant number diagnostic accuracy seemed refractory to sustained change (pulmonary embolism, primary cirrhosis of the liver, gastric/peptic ulcer, and acute coronary thrombosis/myocardial infarction). The findings suggest a new way in which the autopsy can be used to monitor clinical diagnostics to identify possible sources of systematic weaknesses and provide data that can be used to approach the difficult subject of necessary fallibility.

The sensitivity and specificity of clinical diagnostics during five decades. Toward an understanding of necessary fallibility

The sensitivity and specificity of clinical diagnostics during five decades. Toward an understanding of necessary fallibility