Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “diagnostic performance”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources
PubMed1996

Diagnostic performance of Hybrid Capture human papillomavirus deoxyribonucleic acid assay combined with liquid-based cytologic study.

OBJECTIVE: Our purpose was to determine the diagnostic performance of human papillomavirus deoxyribonucleic acid testing when performed on liquid-based (Thin-prep) cytologic samples. STUDY DESIGN: Thin-prep cytologic study, human papillomavirus deoxyribonucleic acid assay with probes for high oncogenic risk human papillomavirus types (16, 18, 31, 33, 35, 45, 51, 52, and 56), and cervical biopsies on women referred to colposcopy for an abnormal Papanicolaou smear were performed. RESULTS: Of the 364 patients, 186 (51.6%) had a low-grade squamous intraepithelial lesion or worse by histologic diagnosis. Human papillomavirus deoxyribonucleic acid quantitation was correlated with a histologic diagnosis of squamous intraepithelial lesion (p < 0.0001) and the morphologic severity (p < 0.01). The combination of Thin-prep cytologic study and human papillomavirus deoxyribonucleic acid testing correctly identified 87.7% of histologic low-grade lesions and 95.1% of the women with high grade lesions and invasive cancer (p < 0.01). CONCLUSIONS: A liquid-based cytologic system provides adequate material for concomitant human papillomavirus testing. Addition of human papillomavirus testing to Thin-prep cytologic study provides significant gains in diagnostic accuracy over either cytologic study or human papillomavirus deoxyribonucleic acid testing alone.

Adolescent↗
PubMed1998

The electrocardiographic exercise test in a population with reduced workup bias: diagnostic performance, computerized interpretation, and multivariable prediction. Veterans Affairs Cooperative Study in Health Services #016 (QUEXTA) Study Group. Quantitative Exercise Testing and Angiography.

BACKGROUND: Empirical scores, computerized ST-segment measurements, and equations have been proposed as tools for improving the diagnostic performance of the exercise test. OBJECTIVE: To compare the diagnostic utility of these scores, measurements, and equations with that of visual ST-segment measurements in patients with reduced workup bias. DESIGN: Prospective analysis. SETTING: 12 university-affiliated Veterans Affairs Medical Centers. PATIENTS: 814 consecutive patients who presented with angina pectoris and agreed to undergo both exercise testing and coronary angiography. MEASUREMENTS: Digital electrocardiographic recorders and angiographic calipers were used for testing at each site, and test results were sent to core laboratories. RESULTS: Although 25% of patients had previously had testing, workup bias was reduced, as shown by comparison with a pilot study group. This reduction resulted in a sensitivity of 45% and a specificity of 85% for visual analysis. Computerized measurements and visual analysis had similar diagnostic power. Equations incorporating nonelectrocardiographic variables and either visual or computerized ST-segment measurement had similar discrimination and were superior to single ST-segment measurements. These equations correctly classified 5 more patients of every 100 tested (areas under the receiver-operating characteristic curve, 0.80 for equations and 0.68 for visual analysis; P < 0.001) in this population with a 50% prevalence of disease. CONCLUSIONS: Standard exercise tests had lower sensitivity but higher specificity in this population with reduced work-up bias than in previous studies. Computerized ST-segment measurements were similar to visual ST-segment measurements made by cardiologists. Considering more than ST-segment measurements can enhance the diagnostic power of the exercise test.

Adult↗
PubMedDate not supplied

Diagnostic performance of clinical examination and selective magnetic resonance imaging in the evaluation of intraarticular knee disorders in children and adolescents.

To determine the diagnostic performances of clinical examination and selective magnetic resonance imaging in the evaluation of intraarticular knee disorders in children and adolescents we compared them with arthroscopic findings in a consecutive series of pediatric patients (< or = 16 years old). Stratification effects by patient age and magnetic resonance imaging center were examined. There were 139 lesions diagnosed clinically, 128 diagnosed by magnetic resonance imaging, and 135 diagnosed arthroscopically. There was no significant difference between clinical examination and magnetic resonance imaging with respect to agreement with arthroscopic findings (clinical examination, 70.3%; magnetic resonance imaging, 73.7%), overall sensitivity (clinical examination, 71.2%; magnetic resonance imaging, 72.0%), and overall specificity (clinical examination, 91.5%; magnetic resonance imaging, 93.5%). Stratified analysis by diagnosis revealed significant differences only for sensitivity of lateral discoid meniscus (clinical examination, 88.9%; magnetic resonance imaging, 38.9%) and specificity of medial meniscal tears (clinical examination, 80.7%; magnetic resonance imaging, 92.0%). For magnetic resonance imaging, children younger than 12 years old had significantly lower overall sensitivity (61.7% versus 78.2%) and lower specificity (90.2% versus 95.5%) compared with children 12 to 16 years old. There was no significant effect of magnetic resonance imaging center. In conclusion, selective magnetic resonance imaging does not provide enhanced diagnostic utility over clinical examination, particularly in children, and should be used judiciously in cases where the clinical diagnosis is uncertain and magnetic resonance imaging input will alter the treatment plan.

Adolescent↗
PubMed2004

Diagnostic performance of the variant lymphocyte flag of the Abbott Cell-Dyn 4000 haematology analyser.

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.

Autoanalysis↗
PubMed2003

[Effect of time elapsed from spontaneous syncope on the diagnostic performance of the head-up tilt table test].

OBJECTIVES: The propensity for spontaneous and tilt-induced neurocardiogenic syncope may exhibit temporal variations. Therefore the diagnostic performance of the head-up tilt test could be improved if it were performed soon after the occurrence of spontaneous syncope. The objective of this study was to assess whether the time interval between the last syncopal episode and tilt table testing influenced the outcome of the test. PATIENTS AND METHOD: Three hundred and fifteen patients undergoing diagnostic tilt table testing potentiated with nitroglycerin for suspected neurocardiogenic syncope were included in the study. The time between the last spontaneous syncope and the tilt table test was recorded and its relationship with the results of the test was analyzed. RESULTS: The tilt table test was positive in 211 patients (67.0%). The time from syncope to test was similar for patients with positive and negative tilt table test results: 28 (1-500) vs 32 (2-700) days (NS). No significant relation was observed between the results of the test and the occurrence of spontaneous syncope during the week, the month or the three months previous to the procedure. However, in men and in patients older than 50 years a higher rate of positive tests was observed if the tilt test was performed within the first month after the last spontaneous syncope. CONCLUSIONS: The time from the last previous spontaneous syncope to the head-up tilt test does not have a significant impact on test outcome in the overall population with suspected neurocardiogenic syncope. However, the rate of positivity might decrease in men and patients older than 50 years if the test is performed later than one month after the spontaneous syncopal episode.

Female↗
PubMed2006

The solitary pulmonary nodule--is it malignant or benign? Diagnostic performance of Tc-depreotide SPECT.

BACKGROUND: The diagnosis of malignancy may be difficult to establish in solitary pulmonary nodules (SPNs). OBJECTIVES: It was the aim of this study to assess diagnostic performances of technetium-99m ((99m)Tc)-depreotide in differentiating benign from malignant SPNs and compare its diagnostic accuracy with fluor-18-fluoro-deoxyglucose positron emission tomography (FDG-PET) in a subgroup of patients. METHODS: One hundred and eighteen patients presenting with an SPN < or =3 cm suspected of malignancy on CT were included in a prospective, open-label, European multicentre trial. Single photon emission computed tomography (SPECT) images were acquired 1.1-4.5 h after injection of 459-770 MBq of (99m)Tc-depreotide. A subset of 29 patients also underwent FDG-PET imaging. Images were interpreted blindly and correlated with histopathology. RESULTS: (99m)Tc-depreotide was positive in 65 of 73 patients with a malignant lesion and negative in 30 of 45 patients with a benign lesion, resulting in a sensitivity, specificity and diagnostic accuracy of 89, 67 and 81%, respectively. In 40 patients with SPN < or =1.5 cm, diagnostic accuracy was 88, sensitivity 75 and specificity 96%. In the subset of 29 patients who underwent both (99m)Tc-depreotide SPECT and FDG-PET imaging, sensitivity, specificity and diagnostic accuracy were identical for both modalities, i.e. 90, 67 and 83%, respectively. CONCLUSIONS: The diagnostic accuracy of (99m)Tc-depreotide SPECT is good and comparable with FDG-PET imaging in SPN of indeterminate origin.

Adolescent↗
PubMed2001

Effect of gamma-irradiation on serum samples on the diagnostic performance of ELISA methods for the detection of trypanosomal antibodies.

The study investigated the effect of gamma-irradiation on bovine serum samples on the ability of enzyme-linked immunosorbent assay (ELISA) methods to detect trypanosomal antibodies. The serum samples were analysed using two standardised indirect ELISA systems. Higher measurement values were observed for most gamma-irradiated antibody positive and negative test samples. Using cut-off points, determined from the analysis of a non-irradiated trypanosomal antibody-negative population, the gamma-irradiated sera data showed that there was an increased risk of misclassifying samples as false positive or cross-reactive due to increased analytical sensitivity and decreased analytical specificity. The intraplate precision and agreement between tested and expected values of measurements were not altered throughout. The impact on the assays' diagnostic performance was estimated by analysing diagnostic sensitivity, diagnostic specificity and related parameters. The data demonstrated that although there was a bias of higher measurement values after gamma-irradiation, this could be compensated after readjustment of the cut-off points to obtain best separation of antibody-positive and -negative samples. Thus, for each assay, no significant difference of the diagnostic proficiency was found before and after gamma-irradiation. The practical implications are discussed of a serum sterilisation procedure using (60)Co gamma-rays for routine sample testing, assay validation and trypanosomosis monitoring and tsetse-fly control and eradication programmes.

Animals↗
PubMed1988

Evaluating diagnostic performance of clinical tests by spreadsheet modeling. Bayesian analysis using Ri/Cj ratio as a unifying concept.

We present a general spreadsheet model for evaluating diagnostic performance of clinical tests. Our model depicts test results as an r X c matrix, with r possible test results and c possible clinical states. Analysis of this matrix is based on the Ri/Cj ratio, calculated as a number of subjects having a specified result Ri within a given clinical state Cj, divided by total subjects within this clinical state. From this model, we can identify three special cases: (1) a 2 X c matrix, with two possible test results of T+ or T-, over c possible clinical states; (2) an r X 2 matrix, with r possible test results, over two possible clinical states of D+ or D-; and (3) a 2 X 2 matrix, with two possible test results over two possible clinical states. Application of the Ri/Cj ratio to the r X c matrix provides a useful approach to graphic analysis of multiple test results over multiple clinical states. The Ri/Cj ratio also provides a general approach to Bayesian analysis, in which likelihood ratio, relative operating characteristic analysis, sensitivity, and specificity represent special cases or special applications.

Bayes Theorem↗
PubMed2003

Trained and supervised physician assistants can safely perform diagnostic cardiac catheterization with coronary angiography.

Using a prospectively collected database of patients undergoing cardiac catheterization, we sought to compare the outcomes of procedures performed by supervised physician assistants (PAs) with those performed by supervised cardiology fellows-in-training. Outcome measures included procedural length, fluoroscopy use, volume of contrast media, and complications including myocardial infarction, stroke, arrhythmia requiring defibrillation or pacemaker placement, pulmonary edema requiring intubation, and vascular complications. Class 3 and 4 congestive heart failure was more common in patients who underwent procedures by fellows compared with those undergoing procedures by PAs (P = 0.001). PA cases tended to be slightly faster (P = 0.05) with less fluoroscopic time (P < 0.001). The incidence of major complications within 24 hr of the procedure was similar between the two groups (0.54% in PA cases and 0.58% in fellow cases). Under the supervision of experienced attending cardiologists, trained PAs can perform diagnostic cardiac catheterization, including coronary angiography, with complication rates similar to those of cardiology fellows-in-training.

Aged↗
PubMed1999

Initial evaluation of the diagnostic performance of the new urinary bladder cancer antigen test as a tumor marker for transitional cell carcinoma of the bladder.

PURPOSE: We evaluated the diagnostic performance of the new noninvasive bladder cancer test on voided urine samples from patients with transitional cell carcinoma compared to symptomatic and asymptomatic controls. MATERIALS AND METHODS: Urinary bladder cancer antigen was measured in urine from 86 patients with active transitional cell carcinoma of the bladder (group 1), 76 patients free of transitional cell carcinoma as confirmed by cystoscopy at followup (group 2), 25 patients with other benign urological diseases (group 3), 25 patients with other malignant pathological conditions (group 4) and 30 healthy subjects free of urological diseases (group 5). RESULTS: Mean urinary bladder cancer antigen concentrations were 104.84, 4.57, 11.79, 48.87 and 1.38 microg/l, for groups 1 to 5, respectively, which was statistically different (p = 0.00005) except for groups 1 and 4 (p = 0.187). Sensitivity was 87.0% (95% confidence interval 79.2 to 92.7) and specificity was 86.8% (77.1 to 93.5%), and both were optimized by receiver operating characteristics plot analysis at a threshold value of 9.74 microg/l using asymptomatic (group 2) compared to known cancer (group 1) cases. CONCLUSIONS: Urinary bladder cancer antigen might have a role as a potential tumor marker for diagnosing transitional cell carcinoma of the bladder.

Aged↗
PubMed2006

Comparison of the diagnostic performance of FDG-PET and VBM-MRI in very mild Alzheimer's disease.

PURPOSE: The aim of this study was to compare the diagnostic performance of( 18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and voxel-based morphometry (VBM) on magnetic resonance imaging (MRI) in the same group of patients with very mild Alzheimer's disease (AD). METHODS: Thirty patients with very mild AD (age 67.0+/-5.8 years; MMSE score 25.5+/-1.2, range 24-28), 32 patients with mild AD (age 67.0+/-4.5 years, MMSE score 22.1+/-0.8, range 21-23) and 60 age- and sex-matched normal volunteers underwent both FDG-PET and three-dimensional spoiled gradient echo MRI. Statistical parametric mapping was used to conduct voxel by voxel analysis and Z score mapping. First, the region of interest (ROI) maps of significant reductions in glucose metabolism and grey matter density in the mild AD patients were defined. Secondly, analysis of receiver operating characteristic (ROC) curves for Z scores in the ROI maps discriminating very mild AD patients and normal controls was performed. RESULTS: In mild AD patients, FDG-PET indicated significant reductions in glucose metabolism in the bilateral posterior cingulate gyri and the right parietotemporal area, while VBM analysis showed a significant decrease in grey matter volume density in the bilateral amygdala/hippocampus complex, compared with the normal control group. ROC analysis showed that in very mild AD patients the accuracy of FDG-PET diagnosis was 89% and that of VBM-MRI diagnosis was 83%. The accuracy of the combination of FDG-PET and VBM-MRI diagnosis was 94%. CONCLUSION: In very mild AD, both FDG-PET and VBM-MRI had high accuracy for diagnosis, but FDG-PET showed slightly higher accuracy than VBM-MRI. Combination of the two techniques will yield a higher diagnostic accuracy in very mild AD by making full use of functional and morphological images.

Aged↗
PubMed2006

Improving the diagnostic performance of lung scintigraphy in suspected pulmonary embolic disease.

AIM: to determine the effectiveness of a new imaging algorithm in the investigation of suspected pulmonary embolism (PE). MATERIALS AND METHODS: A new imaging algorithm for suspected PE was introduced following the installation of a multisection computed tomography (CT) machine at our institution. Before its installation, patients with suspected PE were evaluated with ventilation/perfusion (V/Q) scintigraphy. Subsequently, patients were triaged according to chest radiography (CR) and respiratory history to either lung scintigraphy or CT pulmonary angiography (CTPA). Patients with a normal CR and no history of lung disease were evaluated using perfusion (Q) scintigraphy [ventilation (V) scintigraphy was no longer performed]. Patients with an abnormal CR, asthma or chronic lung disease were evaluated using CTPA. All V/Q images in a continuous 3-year period before the introduction of the new imaging algorithm and all Q images performed in a 3-year period after its introduction were retrospectively reviewed. Imaging reports were categorized into normal, non-diagnostic (low or intermediate probability) or high probability for PE. Patients in the later group who subsequently underwent CTPA, were also reviewed. RESULTS: After the policy change the percentage of normal scintigrams significantly increased (39 to 60%; p<0.001). There was a non-significant increase in the percentage of high probability scintigrams (15 to 18%; p=0.716). Overall the diagnostic yield of lung scintigraphy improved significantly (54 to 78%; p<0.001). CONCLUSION: the diagnostic performance of lung scintigraphy can be improved by careful triage of patients to either Q scintigraphy or CTPA based on clinical history and CR findings. Q scintigraphy remains a valuable diagnostic test in the investigation of suspected PE in carefully selected patients.

Adolescent↗
PubMed2004

Diagnostic performance of MR arthrography in the assessment of superior labral anteroposterior lesions of the shoulder.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic performance of MR arthrography in the assessment of superior labral anteroposterior (SLAP) lesions of the shoulder with emphasis on the classification of SLAP lesions. MATERIALS AND METHODS: Two hundred sixty-five MR arthrograms including 68 MR arthrograms of patients with arthroscopically proven SLAP lesions of the shoulder and 197 MR arthrograms of patients with an intact superior labrum and biceps anchor were retrospectively reviewed in random order. MR arthrography was performed using triplanar T1-weighted spin-echo sequences and a coronal oblique T2-weighted fast spin-echo sequence. MR arthrograms were evaluated by two radiologists with agreement by consensus, and the results were compared with arthroscopic findings. RESULTS: Of 68 SLAP lesions, seven (10%) were arthroscopically classified as type I, 41 (60%) as type II (including 20 type II lesions with coexisting Bankart lesions [29%]), 14 (21%) as type III, and six (9%) as type IV. Compared with arthroscopy as the gold standard, MR arthrography showed a sensitivity of 82% and a specificity of 98% for the overall detection of SLAP lesions. MR arthrographic grading and arthroscopic grading were concurrent in 45 (66%) of 68 arthroscopic diagnoses. Of the surgically confirmed SLAP lesions, involvement of the biceps insertion and SLAP type II lesions with coexisting Bankart lesions were assessed correctly in 75% and 95% of cases, respectively. CONCLUSION: MR arthrography is a highly effective method for the detection of SLAP lesions, but this technique is limited in the classification of different types of SLAP lesions. However, for preoperative planning MR arthrography provides accurate information about the stability of the biceps insertion and the presence of associated anteroinferior labral injuries.

Adolescent↗
PubMed2000

Diagnostic performance of the Roche AMPLICOR PCR in detecting Neisseria gonorrhoeae in genitourinary specimens from female sex workers in Cotonou, Benin.

The objective of this study was to evaluate the diagnostic performance of the Roche multiplex AMPLICOR Chlamydia trachomatis/Neisseria gonorrhoeae PCR test for the detection of Neisseria gonorrhoeae infection in female urine specimens and wet and dry endocervical swabs. Endocervical swabs and urine specimens were collected from 342 female sex workers from Cotonou, Benin, and were tested using the AMPLICOR C. trachomatis/N. gonorrhoeae test (Roche Diagnostic Systems, Inc., Branchburg, N.J.) with internal control detection. Endocervical swabs were also cultured on Thayer-Martin medium. A series of alternate standards that included a combination of all the tests but not the test being evaluated was used to assess the performance of the test with each type of specimen. The sensitivity, specificity, and positive and negative predictive values for the urine were 53.8, 98.9, 93.5, and 87.5%, respectively. Corresponding figures for the wet swab were 91.5, 100, 100, and 97.4%, respectively. Those for the dry swab were 96.3, 96.2, 88.5, and 98.8%, respectively. Based on this study, the AMPLICOR PCR assay showed a low sensitivity for detection of N. gonorrhoeae infection in urine specimens, whereas the test was found to be highly sensitive and specific with endocervical specimens.

Benin↗
PubMed2006

Diagnostic performance of spectroscopic and perfusion MRI for distinction of brain tumors.

OBJECTIVE: To assess the value of spectroscopic and perfusion MRI for glioma grading and for distinguishing glioblastomas from metastases and from CNS lymphomas. METHODS: The authors examined 79 consecutive patients with first detection of a brain neoplasm on nonenhanced CT scans and no therapy prior to evaluation. Spectroscopic MRI; arterial spin-labeling MRI for measuring cerebral blood flow (CBF); first-pass dynamic, susceptibility-weighted, contrast-enhanced MRI for measuring cerebral blood volume; and T1-weighted dynamic contrast-enhanced MRI were performed. Receiver operating characteristic analysis was performed, and optimum thresholds for tumor classification and glioma grading were determined. RESULTS: Perfusion MRI had a higher diagnostic performance than spectroscopic MRI. Because of a significantly higher tumor blood flow in glioblastomas compared with CNS lymphomas, a threshold value of 1.2 for CBF provided sensitivity of 97%, specificity of 80%, positive predictive value (PPV) of 94%, and negative predictive value (NPV) of 89%. Because CBF was significantly higher in peritumoral nonenhancing T2-hyperintense regions of glioblastomas compared with metastases, a threshold value of 0.5 for CBF provided sensitivity, specificity, PPV, and NPV of 100%, 71%, 94%, and 100%. Glioblastomas had the highest tumor blood flow values among all other glioma grades. For discrimination of glioblastomas from grade 3 gliomas, sensitivity was 97%, specificity was 50%, PPV was 84%, and NPV was 86% (CBF threshold value of 1.4), and for discrimination of glioblastomas from grade 2 gliomas, sensitivity was 94%, specificity was 78%, PPV was 94%, and NPV was 78% (CBF threshold value of 1.6). CONCLUSION: Perfusion MRI is predictive in distinguishing glioblastomas from metastases, CNS lymphomas and other gliomas vs MRI and magnetic resonance spectroscopy.

Brain Neoplasms↗
PubMed2004

Diagnostic performance of a commercially available computer-aided diagnosis system for automatic detection of pulmonary nodules: comparison with single and double reading.

OBJECTIVE: To assess the diagnostic performance of a commercially available computer-aided diagnosis (CAD) system for automatic detection of pulmonary nodules with multi-row detector CT scans compared to single and double reading by radiologists. MATERIALS AND METHODS: A CAD system for automatic nodule detection (Siemens LungCare NEV VB10) was applied to four-detector row low-dose CT (LDCT) performed on nine patients with pulmonary metastases and compared to the findings of three radiologists. A standard-dose CT (SDCT) was acquired simultaneously and used for establishing the reference data base. The study design was approved by the Institutional Review Board and the appropriate German authorities. The reference data base consisted of 457 nodules (mean size 3.9 +/- 3.1 mm) and was established by fusion of the sets of nodules detected by three radiologists independently reading LDCT and SDCT and by CAD. An independent radiologist used thin slices to eliminate false positive findings from the reference base. RESULTS: An average sensitivity of 54 % (range 51 % to 55 %) was observed for single reading by one radiologist. CAD demonstrated a similar sensitivity of 55 %. Double reading by two radiologists increased the sensitivity to an average of 67 % (range 67 % to 68 %). The difference to single reading was significant (p < 0.001). CAD as second opinion after single reading increased the sensitivity to 79 % (range 77 % to 81 %), which proved to be significantly better than double reading (p < 0.001). CAD produced more false positive results (7.2 %) than human readers but it was acceptable in clinical routine. CONCLUSION: Double reading with CAD as second reader offered a significantly increased sensitivity compared to conventional double reading. Thus, CAD is a valuable tool for the detection of pulmonary nodules and should be used as second opinion.

Adult↗
PubMed1993

Diagnostic performance and prognostic value of serum troponin T in suspected acute myocardial infarction.

Cardiac troponin T (TnT) is a new serological marker for use as a diagnostic tool for myocardial damage. A blinded prospective multicentre study representing 298 patients suspected of having acute myocardial infarction (AMI), and admitted to the coronary care units of six Scandinavian Hospitals was undertaken to assess the diagnostic performance and prognostic efficacy of a new cardiospecific TnT immunoassay. We used a discriminator TnT value of 0.20 microgram l-1. One hundred and fifty five patients (52%) had definite AMI, based on WHO criteria (all had peak S-TnT values of > or = 0.20 micrograms l-1); 127 patients (43%) had ischaemic heart disease (IHD) without AMI; and 16 patients (5%) had non-IHD (all had peak S-TnT values of < 0.20 microgram l-1). The 127 IHD-patients without definite AMI could be subdivided into a group of 44 patients with S-TnT peak values of > or = 0.20 microgram l-1, and a group of 83 patients with TnT below this level. An equal identification of these patients among the centres was seen (mean +/- SD 35 +/- 13%; range 20-55%). A follow-up study was able to define the clinical significance of these findings. The cumulative 6 months probability of suffering cardiac death or AMI was significantly higher in the subgroup with increased TnT values (14% (6/44)) as compared to the other subgroup (4% (3/83)) (Log-rank test, p = 0.025). The probability of cardiac events was 15% for the patients with definite AMI.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Digital chest radiography with a large image intensifier. Evaluation of diagnostic performance and patient exposure.

A digital system for chest radiography based on a large image intensifier was compared with a conventional film-screen system. The diagnostic performance was evaluated with special reference to the digital monitor images with a modified version of receiver operating characteristic (ROC) analysis--free response ROC (FROC) analysis--on a chest equivalent phantom. Measurements of spatial resolution and energy imparted were also performed. The detectability of low-contrast objects as well as spatial resolution was better for the full-size film-screen radiographs than for both the digital monitor images and the 100 mm photofluorograms. The image-intensifier system has a potential for considerable dose savings in relation to the conventional technique provided that fluoroscopy is excluded in the positioning of the patients.

Energy Transfer↗