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[Predictive value of diagnostic tests in polytrauma patients with abdominal and craniocerebral injuries].

In a study on 1024 polytrauma patients with craniocerebral injury, abdominal injury was present in 206 (20.11%) of them. In order to identify the intraabdominal organs injury, physical examination and specific diagnostic tests will be used. Their value was calculated by means of informational indices. The main indices, sensitivity, positive predictive value and accuracy were: for physical examination = 81.06%, 90.3%, 94.72%; for peritoneal lavage = 94.17%, 95.12%, 97.94%; for abdominal computed tomography = 98.44%, 97.65% and 99.25%. As one might expect the abdominal computed tomography is the most accurate method for the diagnosis of intraabdominal organs injuries.

Abdominal Injuries↗
PubMed1997

Immunomodulation in vitro. The predictive value of in vitro testing of lung cancer patients' lymphocyte responsiveness to stimulation by Thymex L. A preliminary report.

Eleven lung cancer patients were selected for combined radio and immunotherapy with a thymic agent-Thymex L. The selection criteria included the pre-therapy testing of patients' immunocompetence and the responsiveness of their lymphocytes to the in vitro addition of Thymex L: only patients with a significant degree of immunodepression, whose depressed cellular immunity parameters (the number of total and active T cells and their mitogen-induced lymphoproliferative response) were significantly increased upon this agent's action in vitro, entered the study. The results of the pre-therapy in vitro stimulation correlated with those obtained after completion of radioimmunotherapy: the administration of Thymex L along with radiotherapy seances prevented iatrogenic deterioration of initial depression of general immunocompetence and enabled to overcome it to a certain degree. This indicates that pre-therapy in vitro testing has a true predictive value. However, the initial immune disturbances were not normalized by immunotherapy; the post-therapy testing of the patients' lymphocytes to the addition of Thymex L in vitro showed that these cells possessed a residual potential to respond by a significant increase of the active T cell number and proliferative capacity, suggesting that immunotherapy could be prolonged in order to potentiate cellular immunity in immunodepressed lung cancer patients.

Adjuvants, Immunologic↗
PubMed2007

The value of different screening tests in predicting prostate biopsy outcome in screening for prostate cancer data from a multicenter study (ERSPC).

BACKGROUND: Although serum PSA testing is widely used as a screening test for prostate cancer (PC), it is known that it is not specific for PC. The study described here focuses on the value of screening tests next to PSA in identifying men with an elevated risk of having PC and the differences between three centers of the European Randomised study of Screening for Prostate Cancer (ERSPC). METHODS: The study population consists of 2,483 men with a PSA > or =4.0 ng/ml, all biopsied. We assessed data on age, serum PSA level at initial and repeat screening, prostate volume, number of positive DRE and TRUS findings, number of previous negative biopsies, and PPV of the three centers and overall. Using logistic regression analysis, predictors for biopsy outcome at repeat screening in men with a PSA value > or =4.0 ng/ml were determined on the complete dataset and per center. RESULTS: In 2,483 men biopsied, 665 cancers were detected (PPV = 26.8%). Data show that all predictors except prostate volume loose their predictive value in men previously biopsied. In men not previously biopsied, the predictive value of DRE and TRUS vary considerably among the three centers. CONCLUSIONS: Looking at the differences in the predictive value of screening tests in three "comparable" centers, generasibility is not as straightforward as it seems. Using a nomogram for predictive purposes developed elsewhere will require a thorough knowledge of the patient population of which it is derived, and one should interpret its results with a critical mind.

Aged↗
PubMed2006

Simulation model estimates of test accuracy and predictive values for the Danish Salmonella surveillance program in dairy herds.

The Danish government and cattle industry instituted a Salmonella surveillance program in October 2002 to help reduce Salmonella enterica subsp. enterica serotype Dublin (S. Dublin) infections. All dairy herds are tested by measuring antibodies in bulk tank milk at 3-month intervals. The program is based on a well-established ELISA, but the overall test program accuracy and misclassification was not previously investigated. We developed a model to simulate repeated bulk tank milk antibody measurements for dairy herds conditional on true infection status. The distributions of bulk tank milk antibody measurements for infected and noninfected herds were determined from field study data. Herd infection was defined as having either >or=1 Salmonella culture-positive fecal sample or >or=5% within-herd prevalence based on antibody measurements in serum or milk from individual animals. No distinction was made between Dublin and other Salmonella serotypes which cross-react in the ELISA. The simulation model was used to estimate the accuracy of herd classification for true herd-level prevalence values ranging from 0.02 to 0.5. Test program sensitivity was 0.95 across the range of prevalence values evaluated. Specificity was inversely related to prevalence and ranged from 0.83 to 0.98. For a true herd-level infection prevalence of 15%, the estimate for specificity (Sp) was 0.96. Also at the 15% herd-level prevalence, approximately 99% of herds classified as negative in the program would be truly noninfected and 80% of herds classified as positive would be infected. The predictive values were consistent with the primary goal of the surveillance program which was to have confidence that herds classified negative would be free of Salmonella infection.

Animals↗
PubMed1984

Tuberculosis screening.

In view of the decreasing prevalence of tuberculosis, it is important to be aware of the factors influencing the sensitivity, specificity and predictive value of tuberculin testing. The small predictive value of tuberculin testing in a low-risk population makes it an ineffective means for screening. Even in high-risk populations, factors such as geographic location, reaction size, previous skin testing and BCG vaccination significantly influence interpretation of the skin test.

BCG Vaccine↗
PubMed1998

Bronchoscopy with transbronchial biopsies: measurement of bleeding volume and evaluation of the predictive value of coagulation tests.

The objectives of this study were to measure the bleeding volume associated with fibreoptic bronchoscopy with transbronchial biopsies (TBB), to correlate it with coagulation tests and to compare bleeding volume in patients with and without lung transplant. A total of 104 consecutive TBB in 51 different patients was evaluated prospectively. Before each procedure, haemoglobin, blood platelets, prothrombin time (PT), activated partial thromboplastin time (aPTT) and bleeding time were measured. During the procedure, lavage fluid and blood were collected by suction. The haemoglobin concentration of the mixture was measured and bleeding volume was calculated. Clinically significant bleeding was arbitrarily defined as >20 mL blood present in lavage fluid. The mean+/-SD bleeding volume was 7+/-10 mL with no statistically significant difference between transplanted and nontransplanted patients. In eight procedures (7.7%) the bleeding volume was >20 mL (range 22-61 mL). Prebiopsy values for blood platelet counts, PT and aPTT did not predict a bleeding tendency in any of the procedures in which significant bleeding occurred. No correlation was found between bleeding time and bleeding volume in the 17 procedures performed in patients with a prolonged bleeding time (> or =10 min). The bleeding associated with transbronchial biopsies was usually minor and quantitatively similar in patients with or without lung transplant. Coagulation tests could not predict clinically significant bleeding, which may occur in patients with normal coagulation test results.

Adult↗
PubMed1978

The predictive value of clinical laboratory test results.

Bayes' formula is being used with increasing frequency to calculate predictive values for positive and negative clinical laboratory test results. Because of its nonlinear form, however, it is difficult to visualize how changes in the test characteristics or disease prevalence will effect predictive values. This paper shows that Bayes' formula is transformed to a linear function through the use of odds, rather than probabilities, thus facilitating conceptualization, understanding, and memory.

Bayes Theorem↗
PubMed1994

The influence of thrombolytic therapy on the predictive value of exercise testing 3 weeks after acute myocardial infarction.

OBJECTIVES: To evaluate the prognostic value of exercise testing performed soon after acute myocardial infarction (AMI) in patients treated with thrombolytic therapy. DESIGN: A 1-year prospective follow-up of 185 subjects treated with thrombolytic therapy who survived AMI, and who performed exercise testing 3 weeks after AMI. These patients were compared with 272 patients not receiving thrombolytic therapy during the same period. SUBJECTS: Patients recovering from AMI, without medical contraindications to exercise testing performed 3 weeks after AMI. MAIN OUTCOME MEASURES: ST-segment deviations during exercise testing 3 weeks post-AMI were related to clinical outcome 1-year post-AMI and to the administration of thrombolytic therapy during the acute phase of infarction. RESULTS: In patients treated with thrombolytic therapy, the only exercise-test-related parameter predicting subsequent cardiac events was ST-segment elevation. In contrast, patients not receiving thrombolytic therapy and demonstrating ST-segment depression of > or = 1 mm during exercise had more clinical cardiac events than those without this finding (12.3 vs. 3.9%; P < 0.05). CONCLUSION: This study casts doubt on the ability of exercise testing to select a high-risk population requiring early intervention to prevent recurrent coronary events after thrombolysis for AMI.

Adult↗
PubMed1991

Predictive value of coagulation testing in cardiopulmonary bypass surgery.

Severe postoperative bleeding in cardiopulmonary bypass surgery is still a major problem. One hundred and seven patients undergoing uncomplicated coronary artery bypass grafting (CABG) were studied. Two groups were formed according to the patients' 24 hours postoperative mediastinal blood loss. Patients in group I (n = 70) had blood loss less than 1000 ml and patients in group II (n = 33) had blood loss over 1000 ml. Between the two groups, there were no differences in age, male-female ratio, number of grafts, by pass-time or heparin-protamine dose. Coagulation testing: APTT (Activated Partial Thromboplastin Time), PT (Prothrombin Time), fibrinogen, D-dim. (D-dimers), bleeding time, MPV (mean platelet volume) and platelet count, was done preoperatively (T0), immediately postoperatively (T1), 6 hours postoperatively (T2). We were especially interested in the predictive value of hemostatic parameters at T0 and T1. We found a slight but statistically negative correlation between the platelet count (T0 and T1) and the postoperative blood loss.

Blood Coagulation Tests↗
PubMed1975

The predictive value of thyroid "test profile" in habitual abortion.

A characteristic thyroid test profile is observed in pregnancy; it consists of an elevated serum thyroxine (T4I), thyroxine binding globulin (TBG) and electrophoretic index (EI) with lowered triiodothyronine resin uptake (T3U), the free thyroxine index (FTI) remaining in the normal range. An investigation was made of progressive changes in these parameters in 70 normal pregnant women, 34 pregnant women with a past history of habitual abortion who carried to term, seven habitual aborters who miscarried again, and 49 women at the time of spontaneous miscarriage. The results indicated that normal women reached a typical pregnancy thyroid test profile at seven to eight weeks' gestation while habitual aborters carrying a pregnancy to term reached it at 14 to 15 weeks and almost all patients who miscarried never reached it at all. In addition, four women who had aborted previously and were treated with thyroxine throughout six pregnancies, developed a normal "thyroid profile" and carried their pregnancy to term. The significance of the "predictive value" of the test profile is discussed.

Abortion, Habitual↗
PubMed1992

Receiver-operator characteristic, efficiency analysis, and predictive value of serum progesterone concentration as a test for abnormal gestations.

OBJECTIVE: Our objective was to determine if a discriminatory progesterone concentration could be established that confidently predicted abnormal early gestations. STUDY DESIGN: We analyzed differences in progesterone concentrations between normal (n = 40) and abnormal (n = 34) pregnancies during the first 49 days of gestation. The receiver-operator characteristic curve, test efficiency, and predictive value of serum progesterone to discriminate between an abnormal and normal first-trimester gestation were calculated for progesterone concentrations between 5 and 25 ng/ml. RESULTS: Receiver-operator characteristic curve analysis indicated that the best discriminatory progesterone concentration was 10 ng/ml. Test efficiency was maximum between serum progesterone concentration of 9 to 14 ng/ml (80%). When progesterone was less than 10 ng/ml, the predictive value of the abnormal test result was greater than 90%. CONCLUSION: Receiver-operator characteristic analysis, test efficiency, and the predictive value of an abnormal test result suggest that the best progesterone cut off point that predicts abnormal early pregnancies is 10 ng/ml.

Abortion, Spontaneous↗
PubMed2003

The predictive value of cytologic testing in women with the human immunodeficiency virus who have low-grade squamous cervical lesions: a substudy of a randomized, phase III chemoprevention trial.

OBJECTIVE: The purpose of this study was to determine whether the progression of low-grade squamous intraepithelial lesions of the cervix in women with the human immunodeficiency virus can be predicted reliably by standard cytologic testing. STUDY DESIGN: As part of a previously reported trial, 288 biopsy specimens were collected from 117 women with the human immunodeficiency virus. These specimens underwent central and local interpretation, which were compared and correlated with cytologic results. Ninety-two subjects had matched cytologic/histologic pairs at study termination, which were compared to determine whether cytologic testing was predictive of progression. RESULTS: Of the central histologic interpretations, 26 of 288 interpretations (9%) differed from local results, 97 of 246 cytologic/histologic pairs (39%) were discordant, and 21 subjects had progression to high-grade squamous intraepithelial lesions by histologic evidence. Cytologic testing showed high-grade squamous intraepithelial lesions in 4 of 21 specimens (sensitivity, 19%). The remaining cytologic specimens were either low-grade squamous intraepithelial lesions or were normal. CONCLUSION: This substudy of pathologic results from a randomized clinical trial suggests that, although the risk of progression of low-grade squamous intraepithelial lesions is low, follow-up cytologic testing is unreliable. Colposcopic evaluation with directed biopsies should be continued.

Antineoplastic Agents↗
PubMed1993

Predictive value of screening tests for persistent hepatitis C virus infection evidenced by viraemia. Japanese experience.

In November 1989, Japanese Red Cross Blood Centres started screening for hepatitis C virus (HCV) with enzyme-linked immunosorbent assay (Elisa) for the C100-3 viral peptide as the first such nationwide programme in the world. Thereafter post-transfusion non-A non-B hepatitis (PTNANBH) was reduced by 61-80%, but this was not as complete a success as our programme to prevent post-transfusion hepatitis B by screening for high titer hepatitis B core antibody, which we began in the same period. In order to acquire more effective control of PTNANBH, the HCV core-related antigen (GOR, N14) and second-generation Elisa (Ortho2, Abbott2) and second-generation antigen agglutination (PA, PHA) tests have been employed. Among 16,500 donors in 11 blood centers, 365 were serologically positive by at least one of these tests. Among these, HCV RNA was detected in 138 units and the remaining 227 were HCV RNA negatives. The effectiveness of these serological tests to detect HCV RNA-positive status were analyzed. Passive haemagglutination and particle agglutination (PHA and PA) tests were highly effective to predict HCV viraemia among blood donors. Also, these tests can easily determine antibody titre. By either PHA or PA, all units with > or = 2(12) agglutination titre (120 and 122 units) were HCV RNA positive and all agglutination-positive units with serum alanine aminotransferase level higher than 35 Karmen units were HCV RNA positive.(ABSTRACT TRUNCATED AT 250 WORDS)

Alanine Transaminase↗
PubMed1997

Antiphospholipid antibodies: predictive value of laboratory tests.

aPL antibodies are a wide and heterogeneous family of autoantibodies, formerly believed to be directed at anionic phospholipids. In recent years they have been shown to be directed at plasma proteins bound to suitable (phospholipid) anionic surface: beta 2-GPI and prothrombin are the best known and characterized antigens, which are recognized by aCL antibodies and most Lupus Anticoagulants, respectively. The presence of these antibodies has been associated with arterial and venous thrombosis, recurrent miscarriages and thrombocytopenia in the so-called "Antiphospholipid Syndrome". Retrospective and "cross-sectional" studies have established the role of aCL antibodies and Lupus Anticoagulants as risk factors for both venous and arterial thrombosis, the most common clinical manifestations of APS. Prospective studies performed in different patients' populations have validated the association between aCL antibodies and Lupus Anticoagulants with venous and, possibly, arterial thrombosis. Along with the concept of the heterogenity of aPL antibodies there is the observation that among Lupus Anticoagulants aCL-type A, but not LA antibodies, appear to represent a risk factor for thrombosis. However, informations on the predictive value of the various laboratory tests with respect to thrombosis are still rather limited. It is, therefore, necessary to continue the development and standardization of assays that selectively identify aPL antibodies associated with an increased risk of thrombosis, in order to help the clinicians to establish the most appropriate therapeutic strategies for the prevention of the thromboembolic complication of APS.

Antibodies, Antiphospholipid↗
PubMed1994

Screening for peripheral arterial disease: the sensitivity, specificity, and predictive value of noninvasive tests in a defined population.

Large vessel peripheral arterial disease (LV-PAD) is a common condition that causes significant morbidity and disability. The authors evaluated the individual components of a comprehensive noninvasive vascular examination to identify the most sensitive and specific measurements for diagnosing LV-PAD. This cohort, initially screened between 1979 and 1981 in Rancho Bernardo, California, included 421 normal subjects and 63 subjects with LV-PAD. Segmental blood pressure ratios and flow velocities by Doppler ultrasound were used to define cases of LV-PAD. The sensitivity, specificity, positive predictive value, and negative predictive value of each individual component of the diagnostic algorithm were determined. Overall, measurements of posterior tibial flow showed the highest sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy. In addition, an absent or non-recordable posterior tibial peak forward flow, occurring in 96% of all limbs with isolated posterior tibial disease, or an ankle ratio < or = 0.8 considered in parallel yielded a test with sensitivity of 89%, specificity of 99%, positive predictive value of 90%, negative predictive value of 99%, and overall accuracy of 98%. These results indicate that the vast majority of LV-PAD cases can be detected with a single measurement using a handheld Doppler flowmeter employed at the ankle.

Adult↗