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At least 991 records · Page 55Linked to original sources
PubMed2000

Diagnostic radiologists' subspecialization and fields of practice.

OBJECTIVE: The purpose of this study was to explore the diagnostic radiology profession from the perspective of subspecialization and fields of practice. MATERIALS AND METHODS: Data for 1244 practicing diagnostic radiologists were gathered from the American College of Radiology's 1995 Survey of Radiologists. Radiation oncologists, the retired, and residents and fellows were excluded. Responses were weighted to represent all practicing diagnostic radiologists in the United States and were compared with a similar previous survey. RESULTS: More than one quarter (28%) of diagnostic radiologists are subspecialists. Diagnostic radiology subspecialists were more likely than generalists to have fellowship training, work in center cities, work in large groups, and be employed by an academic institution. They were also generally younger and provided a narrower range of imaging services than generalists. CONCLUSION: Although most diagnostic radiologists are generalists, subspecialization will likely continue to grow.

Adult↗
PubMed2000

Impact in the emergency department of unenhanced CT on diagnostic confidence and therapeutic efficacy in patients with suspected renal colic: a prospective survey. 2000 ARRS President's Award. American Roentgen Ray Society.

OBJECTIVE: Our objective was to evaluate the impact of unenhanced CT on clinician diagnostic confidence and therapeutic efficacy in emergency department patients with clinically suspected renal colic. SUBJECTS AND METHODS: Questionnaires were completed on 93 patients who were referred to the radiology department with clinically suspected renal colic. We prospectively surveyed the clinician's diagnostic confidence and treatment plan before and after unenhanced abdominal and pelvic CT. RESULTS: Fifty-six patients (60%) had positive findings for calculi, 20 patients (22%) had normal findings, and alternative diagnoses were found in 17 patients (18%). The clinician's diagnostic certainty of stones before CT was variable with the largest frequencies at 41-60% (n = 30) and 71-90% (n = 35). The diagnostic certainty of stones after CT showed movement toward either less than or equal to 10% (n = 25) or greater than or equal to 91% (n = 51). The mean change in diagnostic confidence was 34%. Fifty-seven patients (61%) had a change in treatment plan. Specifically, the need for urology consultation as the initial treatment plan was reduced from 24 patients to one patient. Plans for admissions suggested before CT (n = 11) were nearly cut in half (n = 6) after imaging. Lastly, seven patients who would have initially been discharged were admitted to the hospital after imaging. CONCLUSION: CT significantly increased emergency department clinician diagnostic confidence and altered initial treatment decisions in patients with suspected renal colic. Most often, CT confirmed a ureteral stone and allowed appropriate discharge or urologic intervention. In a smaller subset of patients, CT established a significant alternative diagnosis that allowed the prompt initiation of appropriate treatment.

Adult↗
PubMed2002

Differential value of comparison with previous examinations in diagnostic versus screening mammography.

OBJECTIVE: The purpose of our study was to analyze the differences in clinical outcomes of diagnostic and screening mammography depending on whether comparison is made with previous examinations. MATERIALS AND METHODS: We analyzed 48,281 consecutive mammography examinations for which previous mammography (9825 diagnostic, 38,456 screening) had been performed between 1997 and 2001, collecting data on demographics, whether comparison actually was made with previous examinations, abnormal findings (recall for screening mammography or biopsy recommendation for diagnostic mammography), biopsy yield of cancer, cancer detection rate, size of invasive cancers, axillary nodal status, and cancer stage. RESULTS: Comparison with previous examinations in the incidence screening setting decreases the recall rate from 4.9% to 3.8% (p < 0.0001) but does not significantly affect the biopsy yield (40-44%, p = 0.56) or the cancer detection rate (5.5-5.2/1000, p = 0.87). In the diagnostic setting, comparison with previous examinations increases the biopsy-recommended rate from 4.3% to 9.4% (p < 0.0001), the biopsy yield from 38% to 51% (p = 0.12), and the overall cancer detection rate from 11/1000 to 39/1000 (p < 0.0001). Comparison with previous examinations is not associated with a significant difference in mean tumor size. However, it is associated with a significant decrease in the frequency of axillary node metastasis and the cancer stage for screening mammography, but not for diagnostic mammography. CONCLUSION: For screening mammography, comparison with previous examinations significantly decreases false-positive but not true-positive findings and permits detection of cancers at an earlier stage. For diagnostic mammography, comparison with previous examinations increases true-positive findings.

Biopsy, Needle↗
PubMed2003

An evaluation of diagnostic data in comparison to the results of liver biopsies in mature horses.

REASONS FOR PERFORMING STUDY: The diagnostic value of several investigative procedures commonly used during the evaluation of suspected equine hepatopathy cases has not been specifically quantified in previous studies. HYPOTHESIS: No noninvasive procedures would clearly discriminate between horses with and without significant liver disease. METHODS: Histopathology of biopsy samples was used as the 'gold standard' technique for definitive diagnosis of the presence or absence of significant liver disease. Clinical, ultrasonographic and clinicopathological data obtained during the investigation of 82 suspected cases of hepatopathy in mature horses were compared with the results of subsequent biopsy in order to quantify the diagnostic value of each test. RESULTS: Of the 82 cases, 61 were confirmed to have significant liver disease and 21 were not. Only serum concentrations of gamma-glutamyltransferase (gammaGT), globulins and alkaline phosphatase (AP) were found to be significantly different between the 2 groups of horses. Clinical and ultrasonographic abnormalities were found, when present, to be good indicators of the presence of liver disease. Certain single serum biochemical tests and combinations thereof were found to have high values for sensitivity (SN), specificity (SP), positive predictive value (PPV) and/or negative predictive value (NPV), but none showed high values for all 4 parameters leading to important limitations in their practical diagnostic application. Of all serum biochemical tests studied, the PPVs of only gammaGT and globulins could be clearly improved by considering especially high positive results. CONCLUSIONS: The single positive test results of greatest diagnostic value were presence of hepatic encephalopathy (HE), increased gammaGT, hyperglobulinaemia, hypoalbuminaemia, increased AP, increased total bile acids (TBA) and increased total bilirubin (TBil). Increased aspartate aminotransferase (AST) and increased glutamate dehydrogenase (GLDH) were also of good diagnostic value, but only when used in combination with the above tests. However, no single, combination or sequential test was able to discriminate fully between horses with and without biopsy-confirmed liver disease and reliance on the use of noninvasive tests for the prediction of the presence or absence of significant liver disease may lead to frequent diagnostic errors. Although certain positive results did reliably predict the presence of liver disease, negative test results were invariably poor predictors of the absence of liver disease. POTENTIAL RELEVANCE: Application of the findings in this study may not be directly applicable to other case populations. However, the results may help clinicians with their selection and interpretation of appropriate test results in cases of suspected liver disease.

Animals↗
PubMed1998

Comparison between register and structured interview diagnoses of schizophrenia: a case for longitudinal diagnostic profiles.

OBJECTIVE: Mental health registers contain diagnoses from serial contacts with mental health facilities over many years. This study examines the relationship between longitudinal diagnostic profiles and structured interview diagnoses. The aim is to improve the definition of diagnoses drawn from clinical case registers. METHOD: The Tasmanian Mental Health Case Register includes 1922 individuals, each with at least one diagnosis of schizophrenia between 1965 and 1990. A representative subsample of 29 individuals were assessed by the structured diagnostic interview for DSM-III-R (SCID). Diagnostic agreement between Register and SCID diagnoses was compared. RESULTS: Twenty-four subjects (82.8%) received a lifetime diagnosis of schizophrenia on the SCID. For each subject, 'schizophrenia diagnostic dominance', the percentage of register entries with schizophrenia diagnoses over total entries, was calculated. Agreement between register and SCID correlated positively with schizophrenia diagnostic dominance and negatively with register mood diagnoses. CONCLUSIONS: Longitudinal diagnostic profiles on databases may be superior to cross-sectional clinical diagnoses in predicting structured interview diagnoses, and may be useful in defining caseness in epidemiological studies using register diagnoses.

Bipolar Disorder↗
PubMed1980

Diagnostic correctness of distal blood pressure measurements in patients with arterial insufficiency.

The value of distal blood pressure measurement by strain gauge technique in arterial insufficiency was analysed by means of the so-called direct method for evaluation of diagnostic tests, and by the calculation of the diagnostic specificity (predictive value of a positive test), the diagnostic sensitivity (predictive value of a negative test), and the diagnostic correctness (the proportion of patients correctly classified by the test). A blood pressure gradient greater than or equal to 20 mmHg from arm to ankle had a high diagnostic correctness as a screening procedure for arterial insufficiency among forty out-patients. Likewise, in sixty-seven patients admitted for arterial reconstruction a toe blood pressure < 30 mmHg had a high diagnostic correctness in deciding whether constant pain was in fact ischaemic rest pain. In contrast, distal blood pressure measurement was of no value as an indicator of the walking distance of claudicants or in locating the arterial obliterations. It is proposed, that similar evaluations are performed on other tests for arterial insufficiency.

Adult↗
PubMed1993

Diagnostic accuracy evaluation using ROC curve analysis.

The diagnostic accuracy of a biochemical quantity is inversely related to the overlapping zone between the values of the population suffering from a disease and the population which does not. The ROC curves are an indirect measure of the overlapping zone between both populations. Specimens (plasma and urine) taken from 928 patients with symptoms of acute abdominal pain were used and the catalytic concentration of alpha-amylase, pancreatic alpha-amylase and triacylglycerol lipase (determined by two methods) were measured. Definitive diagnosis was obtained by following the directives of expert groups on the evaluation of diagnostic tests. Diagnostic accuracy was characterized by calculating the diagnostic sensitivity and specificity, by representing the ROC curves and by quantifying the areas under the ROC curves. The catalytic concentration of pancreatic alpha-amylase in plasma was the quantity with a greater area under the ROC curve (A = 0.9740) and then the one which had greatest diagnostic accuracy. If we considered the upper limit of the reference interval to be the cut-off value, the catalytic concentration of pancreatic alpha-amylase in plasma had a diagnostic sensitivity and specificity values of 0.96 and 0.88 respectively for the acute pancreatitis.

Acute Disease↗
PubMed1988

Diagnostic strategy in the management of patients with breast symptoms. A recommended design and present experience.

The diagnostic problems in patients with breast symptoms have increased as the referral pattern has changed. Patients with vague symptoms and atypical palpatory findings are increasing in number. At the same time, the doctor is faced with the demand for greater diagnostic accuracy and, paradoxically, restraint in the use of diagnostic methods. Accordingly, high priority must be given to an effective diagnostic strategy without unnecessary investigations and delaying procedures. Above all, efforts must aim at reducing the number of 'unnecessary' benign biopsies. We are presenting a suggestion for an integrated diagnostic system based upon close collaboration between the general practitioner on one hand and radiologist, surgeon, and pathologist as the expert hospital team on the other. This design has not only entailed greater diagnostic accuracy, it also complies with the demand for conservation of resources.

Breast Neoplasms↗
PubMed2005

Appropriateness of indication and diagnostic yield of colonoscopy: first report based on the 2000 guidelines of the American Society for Gastrointestinal Endoscopy.

AIM: To assess the appropriateness of referrals and to determine the diagnostic yield of colonoscopy according to the 2000 guidelines of the American Society for Gastrointestinal Endoscopy (ASGE). METHODS: A total of 736 consecutive patients (415 males, 321 females; mean age 43.6+/-16.6 years) undergoing colonoscopy during October 2001-March 2002 were prospectively enrolled in the study. The 2000 ASGE guidelines were used to assess the appropriateness of the indications for the procedure. Diagnostic yield was defined as the ratio between significant findings detected on colonoscopy and the total number of procedures performed for that indication. RESULTS: The large majority (64%) of patients had colonoscopy for an indication that was considered "generally indicated", it was "generally not indicated" for 20%, and it was "not listed" for 16% in the guidelines. The diagnostic yield of colonoscopy was highest for the "generally indicated" (38%) followed by "not listed" (13%) and "generally not indicated" (5%) categories. In the multivariable analysis, the diagnostic yield was independently associated with the appropriateness of indication that was "generally indicated" (odds ratio=12.3) and referrals by gastroenterologist (odds ratio =1.9). CONCLUSION: There is a high likelihood of inappropriate referrals for colonoscopy in an open-access endoscopy system. The diagnostic yield of the procedure is dependent on the appropriateness of indication and referring physician's specialty. Certain indications "not listed" in the guidelines have an intermediate diagnostic yield and further studies are required to evaluate whether they should be included in future revisions of the ASGE guidelines.

Adolescent↗
PubMed1999

Color diagnosticity in object recognition.

Does color influence object recognition? In the present study, the degree to which an object was associated with a specific color was referred to as color diagnosticity. Using a feature listing and typicality measure, objects were identified as either high in color diagnosticity or low in color diagnosticity. According to the color diagnosticity hypothesis, color should more strongly influence the recognition of high color diagnostic (HCD) objects (e.g., a banana) than the recognition of low color diagnostic (LCD) objects (e.g., a lamp). This prediction was supported by results from classification, naming, and verification experiments, in which subjects were faster to identify color versions of HCD objects than they were to identify achromatic versions and incongruent color versions. In contrast, subjects were no faster to identify color versions of LCD objects than they were to identify achromatic and incongruent color versions. Moreover, when shape information was degraded but color information preserved, subjects were less impaired in their recognition of degraded HCD objects than of degraded LCD objects, relative to their nondegraded versions. Collectively, these results suggest that color plays a role in the recognition of HCD objects.

Adult↗
PubMed2004

Applications of flow cytometry and immunohistochemistry to diagnostic hematopathology.

OBJECTIVE: Diagnostic hematopathology depends on the applications of flow cytometric immunophenotyping and immunohistochemical immunophenotyping combined with the cytomorphology and histologic features of each case. Select cases may require additional ancillary cytogenetic and molecular studies for diagnosis. The purpose of this review is to focus on the applications of flow cytometric and immunohistochemical immunophenotyping of paraffin-embedded tissue to diagnostic hematopathology. Advantages and disadvantages of these techniques are examined. DATA SOURCES: The literature is extensively reviewed (PubMed 1985-2003) with an emphasis on the most recent applications and those that are most useful clinically, both diagnostically and prognostically. Study Selection.-Studies were selected based on statistically significant results in large studies with reported adequate clinical follow-up. DATA EXTRACTION: The methodology was reviewed in the selected studies to ensure reliable comparison of reported data. DATA SYNTHESIS: Flow cytometric immunophenotyping offers the sensitive detection of antigens for which antibodies may not be available for paraffin immunohistochemical immunophenotyping. However, paraffin immunohistochemical immunophenotyping offers preservation of architecture and evaluation of expression of some proteins, which may not be available by flow cytometric immunophenotyping. These techniques should be used as complimentary tools in diagnostic hematopathology. CONCLUSIONS: There are extensive applications of flow cytometric and immunohistochemical immunophenotyping to diagnostic hematopathology. As cytogenetic and molecular findings evolve in diagnostic hematopathology, there may be additional applications of flow cytometric and immunohistochemical immunophenotyping to this field of pathology.

Flow Cytometry↗
PubMed2004

[Evaluation and estimation of entrance skin dose in patients during diagnostic and interventional radiology procedures].

A study was performed to evaluate the total entrance skin dose (ESD) of patients during diagnostic and interventional radiology procedures (IVR) and to estimate ESD with body mass index (BMI) and fluoroscopy time. The study included 26 cases of transcatheter arterial embolization therapy (TAE) for hepatocellular carcinoma (HCC) and 19 cases of diagnostic digital subtraction angiography (DSA) for HCC. The ESD of patients was evaluated with a zinc-cadmium sensor linked to a digital counter (SDM: skin dose monitor). Exposure doses were measured with SDM attached to the front of the X-ray beam-limiting device like a dose area product monitor. ESD was calculated from the measured exposure dose. In 26 TAE for HCC, ESD was 1793.7+/-739.1 mGy, with the mean fluoroscopic time of 23.5 minutes and 4.4 DSA acquisitions. The fluoroscopic dose rate was 52.4+/-11.5 mGy/min. In 19 diagnostic DSA for HCC, ESD was 962.9+/-375.2 mGy, with the mean fluoroscopic time of 11.1 minutes and 4.0 DSA acquisitions. The fluoroscopic dose rate was 32.7+/-12.7 mGy/min. Although 33.2% of ESD was from fluoroscopy in diagnostic procedures, the figure was 68.8% in TAE procedures. It was demonstrated that the increase in ESD during IVR was caused by the rise of fluoroscopy dose rate caused by high-magnification fluoroscopy and the extension of fluoroscopy time. In order to reduce ESD, it is necessary to use a low fluoroscopy dose rate with low-rate pulse fluoroscopy, in addition to shortening fluoroscopy time. Fluoroscopy time was a poor predictor of risk because it did not correlate well with ESD during IVR (diagnostic procedures r(2)= 0.897, IVR r(2)= 0.594). However, ESD correlated well with the product of BMI and fluoroscopy time (diagnostic procedures r(2)= 0.910, IVR r(2)= 0.783). The linear relationship between ESD and the product of BMI and fluoroscopy time provides a simple monitoring mechanism of the ESD delivered to the patient during interventional radiology procedures. This linear relationship needs to be established for other types of interventional procedures.

Angiography, Digital Subtraction↗
PubMed2001

Excluding pulmonary embolism at the bedside without diagnostic imaging: management of patients with suspected pulmonary embolism presenting to the emergency department by using a simple clinical model and d-dimer.

BACKGROUND: The limitations of the current diagnostic standard, ventilation-perfusion lung scanning, complicate the management of patients with suspected pulmonary embolism. We previously demonstrated that determining the pretest probability can assist with management and that the high negative predictive value of certain D -dimer assays may simplify the diagnostic process. OBJECTIVE: To determine the safety of using a simple clinical model combined with D -dimer assay to manage patients presenting to the emergency department with suspected pulmonary embolism. DESIGN: Prospective cohort study. SETTING: Emergency departments at four tertiary care hospitals in Canada. PATIENTS: 930 consecutive patients with suspected pulmonary embolism. INTERVENTIONS: Physicians first used a clinical model to determine patients' pretest probability of pulmonary embolism and then performed a D -dimer test. Patients with low pretest probability and a negative D -dimer result had no further tests and were considered to have a diagnosis of pulmonary embolism excluded. All other patients underwent ventilation-perfusion lung scanning. If the scan was nondiagnostic, bilateral deep venous ultrasonography was done. Whether further testing (by serial ultrasonography or angiography) was done depended on the patients' pretest probability and the lung scanning results. MEASUREMENTS: Patients received a diagnosis of pulmonary embolism if they had a high-probability ventilation-perfusion scan, an abnormal result on ultrasonography or pulmonary angiography, or a venous thromboembolic event during follow-up. Patients for whom the diagnosis was considered excluded were followed up for 3 months for the development of thromboembolic events. RESULTS: The pretest probability of pulmonary embolism was low, moderate, and high in 527, 339, and 64 patients (1.3%, 16.2%, and 37.5% had pulmonary embolism), respectively. Of 849 patients in whom a diagnosis of pulmonary-embolism had initially been excluded, 5 (0.6% [95% CI, 0.2% to 1.4%]) developed pulmonary embolism or deep venous thrombosis during follow-up. However, 4 of these patients had not undergone the proper diagnostic testing protocol. In 7 of the patients who received a diagnosis of pulmonary embolism, the physician had performed more diagnostic tests than were called for by the algorithm. In 759 of the 849 patients in whom pulmonary embolism was not found on initial evaluation, the diagnostic protocol was followed correctly. Only 1 (0.1% [CI, 0.0% to 0.7%]) of these 759 patients developed thromboembolic events during follow-up. Of the 437 patients with a negative D -dimer result and low clinical probability, only 1 developed pulmonary embolism during follow-up; thus, the negative predictive value for the combined strategy of using the clinical model with D -dimer testing in these patients was 99.5% (CI, 99.1% to 100%). CONCLUSION: Managing patients for suspected pulmonary embolism on the basis of pretest probability and D -dimer result is safe and decreases the need for diagnostic imaging.

Adolescent↗
PubMed2006

Appropriateness of diagnostic management and outcomes of suspected pulmonary embolism.

BACKGROUND: International guidelines include several strategies for diagnosing pulmonary embolism with confidence, but little is known about how these guidelines are implemented in routine practice. OBJECTIVE: To evaluate the appropriateness of diagnostic management of suspected pulmonary embolism and the relationship between diagnostic criteria and outcome. DESIGN: Prospective cohort study with a 3-month follow-up. SETTING: 116 emergency departments in France and 1 in Belgium. PATIENTS: 1529 consecutive outpatients with suspected pulmonary embolism. MEASUREMENTS: Appropriateness of diagnostic criteria according to international guidelines; incidence of thromboembolic events during follow-up. RESULTS: Diagnostic management was inappropriate in 662 (43%) patients: 36 of 429 (8%) patients with confirmed pulmonary embolism and 626 of 1100 (57%) patients in whom pulmonary embolism was ruled out. Independent risk factors for inappropriate management were age older than 75 years (adjusted odds ratio, 2.27 [95% CI, 1.48 to 3.47]), known heart failure (odds ratio, 1.53 [CI, 1.11 to 2.12]), chronic lung disease (odds ratio, 1.39 [CI, 1.00 to 1.94]), current or recent pregnancy (odds ratio, 5.92 [CI, 1.81 to 19.30]), currently receiving anticoagulant treatment (odds ratio, 4.57 [CI, 2.51 to 8.31]), and the lack of a written diagnostic algorithm and clinical probability scoring in the emergency department (odds ratio, 2.54 [CI, 1.51 to 4.28]). Among patients who did not receive anticoagulant treatment, 44 had a thromboembolic event during follow-up: 5 of 418 (1.2%) patients who received appropriate management and 39 of 506 (7.7%) patients who received inappropriate management (absolute risk difference, 6.5 percentage points [CI, 4.0 to 9.1 percentage points]; P < 0.001). Inappropriateness was independently associated with thromboembolism occurrence (adjusted odds ratio, 4.29 [CI, 1.45 to 12.70]). LIMITATIONS: This was an observational study without evaluation of the risk for overdiagnosis. CONCLUSIONS: Diagnostic management that does not adhere to guidelines is frequent and harmful in patients with suspected pulmonary embolism. Several risk factors for inappropriateness constitute useful findings for subsequent interventions.

Belgium↗
PubMed1986

The impact of new diagnostic technologies on health care. An aggregation of expert opinion.

The growing number of applications for both new and existing technologies will act as a catalyst for major changes in the diagnostic testing field over the next decade. The most important single factor affecting diagnostics, however, will be the increasing restrictions on reimbursement for diagnostic tests as traditional payers become much more cost conscious. After decades of growth, we should see a gradual decline in absolute numbers of diagnostic tests and procedures by the early 1990s. The locations of pathology testing may change as well. Free-standing labs will continue to grow in importance while the number of tests in hospitals will decline as hospital admission volumes fall. The number of tests in the home will grow dramatically but will remain a relatively small part of the whole. In diagnostic imaging, rapid growth will occur in the use of some of the newer specialized procedures, but the use of traditional x-rays is likely to fall off slightly. The share of procedures done in hospitals will drop, and the share done in diagnostic imaging centers will show a corresponding growth. These changes are likely to mean fewer radiologists and pathologists, tougher questions about administrative allocation of flat-rate reimbursements, a shift of focus in medical specialist education, and a shift in the role of medical specialty societies.

Clinical Laboratory Techniques↗
PubMed1998

Measuring the quality of diagnostic hypothesis sets for studies of decision support.

Within medical informatics there is widespread interest in computer-based decision support and the evaluation of its impact. It is widely recognized that the measurement of dependent variables, or outcomes, represents the most challenging aspect of this work. This paper describes and reports the reliability and validity of an outcome metric for studies of diagnostic decision support. The results of this study will guide the analytic methods used in our ongoing multi-site study of the effects of decision support on diagnostic reasoning. Our measurement approach conceptualizes the quality of a diagnostic hypothesis set as having two components summed to generate a composite index: a Plausibility Component derived from ratings of each hypothesis in the set, whether correct or incorrect; and a Location Component derived from the location of the correct diagnosis if it appears in the set. The reliability of this metric is determined by the extent of interrater agreement on the plausibility of diagnostic hypotheses. Validity is determined by the extent to which the index generates scores that make sense on inspection (face validity), as well as the extent to which the component scores are non-redundant and discriminate the performance of novices and experts (construct validity). Using data from the pilot and main phases of our ongoing study (n = 124 subjects working 1116 cases), the reliability of our diagnostic quality metric was found to be 0.85-0.88. The metric was found to generate, on inspection, no clearly counterintuitive scores. Using data from the pilot phase of our study (n = 12 subjects working 108 cases), the component scores were moderately correlated (r = 0.68). The composite index, computed by equally weighting both components, was found to discriminate the hypotheses of medical students and attending physicians by 0.97 standard deviation units. Based on these findings, we have adopted this metric for use in our further research exploring the impact of decision support systems on diagnostic reasoning and will make it available to the informatics research community.

Decision Support Systems, Clinical↗
PubMed1999

Diagnostic bitoric rigid gas permeable contact lenses.

PURPOSE: To simplify the fitting of bitoric rigid gas permeable (RGP) contact lenses. METHODS: We prescribed bitoric RGP lenses using two kinds of diagnostic lenses at random. One type of lens was a diagnostic polymethylmethacrylate (PMMA) spherical lens and the other was a diagnostic RGP bitoric lens. RESULTS: The bitoric RGP lenses that were prescribed using a diagnostic bitoric lens required fewer parameter changes compared with the bitoric RGP lens prescribed using a diagnostic PMMA spherical lens. CONCLUSIONS: The diagnostic RGP bitoric lens simplifies the prescription of bitoric RGP lenses and is very useful in fitting astigmatic corneas.

Adolescent↗
PubMed1999

The use of a rapid D-dimer blood test in the diagnostic work-up for pulmonary embolism: a management study.

BACKGROUND: D-dimer assays have a potential to rule out pulmonary embolism in case of a normal test result. We studied the clinical utility of incorporating the SimpliRED D-dimer test result and clinical probability in the routine diagnostic work-up of patients with suspected acute pulmonary embolism. METHODS: In a prospective management study 245 consecutive patients, hospitalised as well as outpatients, were included. A SimpliRED D-dimer test and perfusion/(ventilation) scintigraphy were obtained in all patients, whereas clinical probability was determined in the subgroup of patients with a non-diagnostic scan and normal D-dimer result. A diagnostic algorithm determined the necessity for further testing and decisions about treatment. All patients were followed up for 3 months. RESULTS: In 54 patients (22%) with a normal lung scan and 50 patients (21%) with a high probability lung scan, antithrombotic therapy was withheld or started respectively, irrespective of the D-dimer result. A non-diagnostic lung scan was found in 137 (56%) patients, of whom 70 patients had an abnormal D-dimer test, in whom further testing was ordered. Of the remaining 67 patients with a non-diagnostic lung scan and normal D-dimer test 8 patients had a high clinical probability, and the subsequent ultrasonography and pulmonary angiography yielded pulmonary emboli in 1 patient. In the remaining 66 patients, pulmonary embolism was considered to be absent and antithrombotic treatment was stopped/withheld. During follow-up of these patients only one patient experienced a possible venous thromboembolic event (failure rate 1,5%; 95% CI 0-8%). The SimpliRED D-dimer was normal in 6 of 61 patients with proven pulmonary embolism (sensitivity 90%; 95% CI 80-96%). CONCLUSION: Our findings suggest that it is safe to withhold anticoagulant therapy in those patients with a non-diagnostic lung scan, a normal SimpliRED D-dimer test result, and without a high clinical probability. This results in a substantial decreased need for ultrasonography and pulmonary angiography. The SimpliRED should not be used in isolation to exclude pulmonary embolism.

Adult↗