Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “diagnostics”

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 469 records · Page 26Linked to original sources
PubMed1994

The value of diagnostic information to patients with suspected multiple sclerosis. Rochester-Toronto MRI Study Group.

OBJECTIVE: To determine the value of diagnostic information to patients with suspected multiple sclerosis (MS). Because treatment choices would be only minimally affected by earlier diagnosis for most patients with this clinical problem, this study assessed the "nondecisional" value of diagnosis. DESIGN: Prospective survey of patients before and after diagnostic workup, including imaging with magnetic resonance scanning. We assessed the effect of diagnostic information on patients' sense of well-being, as well as direct measures of the utility of information (using time trade-off and willingness-to-pay techniques). SETTING: Patients referred from primary care practices for diagnostic workup for suspected MS to neurology clinics and practices. PATIENTS: Sixty-eight individuals, mean age 37.5 years, 53 female and 15 male. Thirty-one patients were classified as having "probable MS," and 37 were classified as having "possible MS" by the examining neurologist before workup. MEASUREMENTS: Present and future health perception, uncertainty about diagnosis-prognosis, and level of anxiety. Willingness to pay for diagnostic information, quality of life as measured by the time trade-off technique, and psychological state of the patient before and after diagnosis. RESULTS: Diagnostic uncertainty fell significantly as a result of the diagnostic workup. Most patients (59/62) said that they were better off having received diagnostic information. Although anxiety seemed to be reduced by testing, overall anxiety levels did not decrease as much as anticipated. Patients also became less optimistic about their future health after testing. On average, patients were willing to forgo 4.5 quality-adjusted life days to receive an earlier diagnosis and their quality of life after diagnosis improved slightly. Subgroups of patients differed in their response to diagnostic information. Those in whom no definitive diagnosis emerged tend to be more anxious rather than being reassured by the "negative" workup. Individuals with "positive" workups became less anxious and expressed favorable feelings about the diagnostic workup even though they often faced a chronic disease. CONCLUSIONS: Overall, the diagnostic workup seemed to benefit patients and improve their sense of well-being. However, whether the effects were beneficial or not depended on the results of the diagnostic workup itself. In clinical practice the decision to undergo testing in situations in which definitive treatment is unavailable should be individualized. The potential for negative as well as positive consequences should be recognized.

Adult↗
PubMed2004

Diagnostic I-131 scintigraphy in patients with differentiated thyroid cancer: no additional value of higher scan dose.

OBJECTIVE: After initial treatment with total thyroidectomy and radioiodine ablation, most follow-up protocols for patients with differentiated thyroid carcinoma contain cyclic diagnostic I-131 imaging and serum thyroglobulin measurements. The applied diagnostic I-131 doses vary between 37 and 370 MBq. The aim of this study was to determine the yield of a diagnostic scan with 370 MBq I-131 in patients with a negative diagnostic scan with 74 MBq I-131. METHODS: Retrospective evaluation of 158 patients who received a high-dose diagnostic scan with 370 MBq I-131 because of a negative low-dose diagnostic scan with 74 MBq I-131. Special attention was paid to the patients with positive high-dose diagnostic scanning and undetectable serum thyroglobulin levels after thyroid hormone withdrawal. RESULTS: In 127 (80%) of patients the 370 MBq I-131 scan was negative, just like the preceding low-dose scan. In 31 (20%) of patients abnormal uptake was present on the 370 MBq diagnostic scan. In 19 of these 31 patients serum thyroglobulin was undetectable. In 15/19 the high-dose diagnostic scan proved either false positive or demonstrated clinically irrelevant minor ablation rests. In only four patients (2.5%) did the high-dose diagnostic scans reveal possibly relevant uptake caused by residual differentiated thyroid cancer. CONCLUSION: In 98% of patients a 370 MBq dose of I-131 for diagnostic WBS had no additional value. The combination of a low-dose diagnostic I-131 scan using only 74 MBq combined with a serum Tg level measurement proved sufficient for correct clinical decision making regarding whether the patient requires additional I-131 therapy.

Adolescent↗
PubMed2003

Computerized diagnostic decision support system for the classification of preinvasive cervical squamous lesions.

Previous studies have revealed considerable interobserver and intraobserver variation in the histological classification of preinvasive cervical squamous lesions. The aim of the present study was to develop a decision support system (DSS) for the histological interpretation of these lesions. Knowledge and uncertainty were represented in the form of a Bayesian belief network that permitted the storage of diagnostic knowledge and, for a given case, the collection of evidence in a cumulative manner that provided a final probability for the possible diagnostic outcomes. The network comprised 8 diagnostic histological features (evidence nodes) that were each independently linked to the diagnosis (decision node) by a conditional probability matrix. Diagnostic outcomes comprised normal; koilocytosis; and cervical intraepithelial neoplasia (CIN) I, CIN II, and CIN III. For each evidence feature, a set of images was recorded that represented the full spectrum of change for that feature. The system was designed to be interactive in that the histopathologist was prompted to enter evidence into the network via a specifically designed graphical user interface (i-Path Diagnostics, Belfast, Northern Ireland). Membership functions were used to derive the relative likelihoods for the alternative feature outcomes, the likelihood vector was entered into the network, and the updated diagnostic belief was computed for the diagnostic outcomes and displayed. A cumulative probability graph was generated throughout the diagnostic process and presented on screen. The network was tested on 50 cervical colposcopic biopsy specimens, comprising 10 cases each of normal, koilocytosis, CIN I, CIN II, and CIN III. These had been preselected by a consultant gynecological pathologist. Using conventional morphological assessment, the cases were classified on 2 separate occasions by 2 consultant and 2 junior pathologists. The cases were also then classified using the DSS on 2 occasions by the 4 pathologists and by 2 medical students with no experience in cervical histology. Interobserver and intraobserver agreement using morphology and using the DSS was calculated with kappa statistics. Intraobserver reproducibility using conventional unaided diagnosis was reasonably good (kappa range, 0.688 to 0.861), but interobserver agreement was poor (kappa range, 0.347 to 0.747). Using the DSS improved overall reproducibility between individuals. Using the DSS, however, did not enhance the diagnostic performance of junior pathologists when comparing their DSS-based diagnosis against an experienced consultant. However, the generation of a cumulative probability graph also allowed a comparison of individual performance, how individual features were assessed in the same case, and how this contributed to diagnostic disagreement between individuals. Diagnostic features such as nuclear pleomorphism were shown to be particularly problematic and poorly reproducible. DSSs such as this therefore not only have a role to play in enhancing decision making but also in the study of diagnostic protocol, education, self-assessment, and quality control.

Bayes Theorem↗
PubMed2000

The diagnostic and therapeutic impact of MRI: an observational multi-centre study.

AIM: To provide information about the diagnostic and therapeutic impact of magnetic resonance imaging (MRI) and to compare the findings across diagnostic groups. MATERIALS AND METHODS: A prospective, observational study of 2017 consecutive referrals for MRI of the head, spine or knee at four imaging centres. Clinicians completed questionnaires before MRI stating initial diagnoses, diagnostic confidence and treatment plans. After imaging, a second questionnaire evaluated clinicians' revised diagnosis and treatment plans in the light of imaging findings. Patients were grouped into nine diagnostic categories for analysis. Comparison between pre- and post-imaging was used to assess the diagnostic and therapeutic impact of MRI. RESULTS: In seven of nine diagnostic groups MRI findings were associated with a diagnostic impact. Diagnoses were revised or discarded following normal MR findings and diagnostic confidence was increased by confirmative MR findings. There was no statistically significant diagnostic impact for suspected pituitary or cerebello-pontine angle lesions. In five of nine diagnostic groups (knee meniscus, knee ligament, multiple sclerosis, lumbar and cervical spine) MRI findings had a clear impact on treatment plans. CONCLUSION: This study demonstrates that in most diagnostic categories, MRI influences diagnosis and treatment. However, experimental studies are needed to prove that these diagnostic and therapeutic impacts lead to improved health.Hollingworth (2000). Clinical Radiology55, 825-831.

Craniocerebral Trauma↗
PubMed1998

Diagnostic and management procedures for compensable back injuries without serious associated injuries. Modeling of the 1991 injury cohort from a major Michigan compensation insurer.

STUDY DESIGN: A retrospective cohort of 2425 workers with compensated back conditions was created from the 1991 compensated cohort of the largest compensation insurer in Michigan by linking computerized information on social and demographic factors, diagnostic and management procedures, and cumulative missed worktime. OBJECTIVE: To describe medical care use from date of injury in 1991 to mid-1993 by type of back condition, to identify factors affecting this use, to determine the effect of alternative model selection strategies on identifying such factors, to investigate the timing of surgery and the use of diagnostic studies in patients with displaced or herniated discs with and without surgery, and to compare the use of medical care in the study group with that recommended by national expert panels. SUMMARY OF BACKGROUND DATA: Despite the enormous costs involved in medical care for patients with work-related back injuries, almost no information on the use of medical care is available for compensated back injuries by diagnostic and procedure code. METHODS: Use of medical care was grouped into 18 categories for tabulation. Factors affecting use of medical care were identified by logistic regression, supplemented by Cox analysis for time to first procedure. The Hosmer-Lemeshow chi-square statistic was compared with the Bayes Information Criterion for evaluating model fit. Overall model utility was evaluated by comparing receiver operating characteristic curves generated by the model. For patients with displaced or herniated discs, algorithms were used to identify the diagnostic procedures performed before and after the first surgery and the amount of time that passed before each procedure was performed. RESULTS: In patients with diagnoses of disc displacement or herniation or vertebrogenic neuritis, approximately 80% underwent radiography to obtain plain views of the spine, 75% underwent diagnostic imaging, 45% underwent electrodiagnostic procedures, and 24% underwent spinal surgery (29.3% had surgical procedures among those with disc conditions). In patients with diagnoses of back sprain or other symptomatic diagnoses, the percentages for the first three procedures are approximately 70%, 12%, and 12%, respectively. Diagnostic category, age, gender, and cumulative missed worktime predicted the receipt of diagnostic and treatment procedures. Women were 30% less likely to undergo computed axial tomography or magnetic resonance imaging and 50% less likely to undergo spinal surgery. Median time to spinal surgery was twice as long in the group that underwent diagnostic imaging and electrodiagnostic testing before surgery (134.5 days). Of the 622 patients with disc displacement/herniation, 510 (approximately 80%) had initial diagnostic imaging studies, and, of the 510, 162 (approximately 30%) had surgery. Thirteen (8%) were reoperated. Of the 162 patients who had surgery, 46 (approximately 30%) had follow-up diagnostic imaging, and, of the 46, nine (approximately 20%) were reoperated. Of the 348 managed conservatively, 96 (approximately 30%) had follow-up diagnostic imaging. CONCLUSIONS: The data suggest only modest differences in the use of medical care between this study group and noncompensated study populations from previous reports. The authors of this study estimate that 27% of diagnostic imaging studies and 43% of plain radiography of the spine could have been avoided if then available Canadian recommendations or current American, guidelines had been followed. The gender effect remains unexplained and needs to be investigated in additional studies. There was an increase of 6% in the use of surgery in compensated patients compared with the use of surgery in a recent American series involving traditional health insurance, but this may be associated with greater work disability in the compensated group. The results of the current study suggest that the use and reporting of model selection strategies and the use of receiver operati

Adolescent↗
PubMed2001

Outcome of differentiated thyroid cancer with detectable serum Tg and negative diagnostic (131)I whole body scan: comparison of patients treated with high (131)I activities versus untreated patients.

Detectable serum Tg levels associated with negative diagnostic (131)I whole body scan are not infrequently found in patients with differentiated thyroid cancer. Several researchers have shown that in these patients the administration of high (131)I activity (100 mCi or more) increases the sensitivity of a posttherapy diagnostic (131)I whole body scan performed a few days later and allows the detection of neoplastic foci not seen with diagnostic doses of (131)I. Empirical radioiodine treatment has also been advocated by some researchers, but its therapeutic effect is controversial. In our institute, positive serum Tg/negative diagnostic (131)I whole body scan patients were not treated with high (131)I activities before 1984; afterward, almost all patients with positive serum Tg/negative diagnostic (131)I whole body scan patients were treated with radioiodine, and a posttherapy diagnostic (131)I whole body scan was performed. In the present retrospective study we compared the outcome of these two groups of patients, 42 treated and 28 untreated, followed for mean periods of 6.7 +/- 3.8 and 11.9 +/- 4.4 yr, respectively. In the treated group the first posttherapy diagnostic (131)I whole body scan was negative in 12 patients and positive in 30 patients. (131)I treatment was further administered only in the latter group. At the end of follow-up in treated patients a complete remission (normalization of serum Tg off L-thyroxine and negative diagnostic (131)I whole body scan) was observed in 10 patients (33.3%). In 9 cases (30%) posttherapy diagnostic (131)I whole body scan became negative, and serum Tg was reduced but still detectable; in 11 patients (36.6%) serum Tg was detectable, and posttherapy diagnostic (131)I whole body scan was positive. The resolution of (131)I uptake in lung metastases was observed in 8 of 9 cases (88.8%) and in cervical node metastases in 11 of 18 cases (61.1%). In patients treated only once because the posttherapy diagnostic (131)I whole body scan was negative (n = 12), 2 patients (16.7%) were in apparent remission, 7 (58.3%) had detectable Tg values without evidence of disease, 2 (16.7%) showed lymph node metastases in the mediastinum, and 1 patient (8.3%) died because of lung metastases. Of the 28 untreated patients, none with radiological evidence of disease, serum Tg off L-thyroxine therapy became undetectable in 19 cases (67.9%), significantly reduced in 6 cases (21.4%), and unchanged or increased in 3 patients (10.7%), 1 of whom developed lung metastases 14 yr after the diagnosis. In summary, our results indicate that in patients with detectable serum Tg and negative diagnostic (131)I whole body scan, treatment with high doses of (131)I may have therapeutic utility in patients with lung metastases and, to a lesser extent, in those with lymph node metastases. However, in view of the frequent normalization of Tg values in untreated patients, we believe that treatment with (131)I should be considered according to the result of the first posttherapy scan. If positive in the lung, (131)I treatment should be continued up to total remission; surgical treatment should be preferred in patients with node metastases, and no treatment should be used in those with thyroid bed uptake or no uptake.

Adolescent↗
PubMed2003

Characteristics of good diagnostic studies.

Whether or not patients are better off from undergoing a diagnostic test will depend on how test information is used to guide subsequent decisions on starting, stopping, or modifying treatment. Consequently, the practical value of a diagnostic test can only be assessed by taking into account subsequent health outcomes. In the appraisal of diagnostic test studies, it is essential to discriminate between studies that report on the accuracy of a diagnostic test and studies that report on health outcomes of strategies that incorporate diagnostic tests. In a study that reports on diagnostic accuracy, a cohort of patients is subjected to at least two diagnostic tests: the index test and the reference test, the latter usually being the best method available to detect the target condition. The accuracy of the index test can be expressed in terms of sensitivity, specificity, or likelihood ratios. Studies that compare two or more strategies that incorporate diagnostic tests as well as therapeutic interventions should be approached differently. Such studies do not require expression of test accuracy in terms of sensitivity and specificity. The merit of diagnostic tests evaluated in such studies can be expressed by comparing relevant outcomes of both strategies. The effectiveness of such strategies can be compared similarly as the effectiveness of treatment. However, due to the fact that the effect of a diagnostic test on health outcome is not as direct as the effect of treatment on health outcome, the design of outcome studies reporting on diagnostic tests requires special attention. It is important to establish a clear link between the result of the test under study and subsequent therapeutic management. Furthermore, trial efficiency can be improved by moving the point of randomization from the decision point, whether or not to test, to the point where a decision has to be made regarding what to do with the positive test results.

Antibodies, Bacterial↗
PubMed2006

Diagnosis of lumbar spinal stenosis: a systematic review of the accuracy of diagnostic tests.

STUDY DESIGN: Systematic review of diagnostic studies. OBJECTIVE: To investigate the diagnostic performance of tests used to detect lumbar spinal stenosis. SUMMARY OF BACKGROUND DATA: Little is known about the diagnostic accuracy of tests in detecting lumbar spinal stenosis. A systematic review will provide more insight in this topic. METHODS: We performed a literature search in Medline (PubMed) and Embase for original diagnostic studies on lumbar spinal stenosis, in which one or more different tests were evaluated with a reference standard, and diagnostic values were reported or could be calculated. Two reviewers independently checked all abstracts and full text articles for inclusion criteria. Included articles were assessed for their quality using the Quadas tool. Study features and diagnostic values were extracted from the included studies. RESULTS: Of the 24 articles included in this review, 15 concerned imaging tests, 7 evaluated "clinical tests," and 2 reported on other diagnostic tests. The overall quality was poor; only 5 studies scored positive on more than 50% of the quality items. Estimates of the diagnostic value of the tests differed considerably. The imaging studies showed no superior accuracy for myelography compared with CT or MRI. Overall, there is considerable variation in the clinical tests; some studies show high sensitivity, whereas others show high specificity. CONCLUSIONS: Because of heterogeneity and overall poor quality, no firm conclusions about the diagnostic performance of the different tests can be drawn. Better-designed studies exploring the accuracy of diagnostic tests are needed to improve the diagnostic policy.

Diagnostic Tests, Routine↗
PubMed2006

Diagnostic agreement of schizophrenia spectrum disorders among chronic patients with functional psychoses.

BACKGROUND: To investigate whether diagnostic agreement across different diagnostic systems improves in a sample of chronic patients suffering from functional psychosis compared to first-admitted patients. SAMPLING AND METHODS: Among 353 patients with a history of functional psychosis, a subset of 100 individuals (35 women and 65 men) were randomly sampled and assessed using the Operational Criteria Checklist for Psychotic Illness and Affective Illness (OPCRIT). Based on the OPCRIT diagnoses the subjects suffering from schizophrenia and schizophrenia spectrum disorders according to seven diagnostic systems were identified. Diagnostic agreement was assessed using unweighted kappa-statistics and pairwise concordance rates (CR). RESULTS: High diagnostic agreement of schizophrenia was observed across the ICD-10 and DSM systems (CR >0.70, kappa >0.70), which all had a significantly lower concordance to the St. Louis Criteria (SLC), research diagnostic criteria and Schneider's first rank symptoms (FRS) (0.32< CR <0.66; -0.10< kappa <0.51). Agreement on schizophrenia across all systems was observed for one fourth of the subjects. Elimination of the diagnostic impact of 'co-occurrence of psychotic and affective symptoms' excluded FRS standalone individuals from the sample, increased overall homogeneity and resulted in a dichotomized sample according to SLC (46 positive vs. 47 negative). SLC status could be predicted in 78% of cases by four items relating to family history and psychosocial function previous to the onset of illness. Similarly high pairwise CR were observed for schizophrenia spectrum disorders across all diagnostic systems. CONCLUSIONS: This study demonstrates that diagnostic agreement is higher among chronic patients than that observed in subjects with a recent onset of psychosis, although considerable discordance is also observed in this chronic sample. However, the discordance among chronic patients with functional psychosis largely derives from the different emphasis that diagnostic systems place on co-occurrence of psychotic and affective symptoms. This may have serious epistemological consequences, thus underlining the conventional nature of the present schizophrenia diagnoses and the need for biologically founded diagnostic criteria.

Adult↗
PubMed2006

Diagnostic tests and algorithms used in the investigation of haematuria: systematic reviews and economic evaluation.

OBJECTIVES: To determine the most effective diagnostic strategy for the investigation of microscopic and macroscopic haematuria in adults. DATA SOURCES: Electronic databases from inception to October 2003, updated in August 2004. REVIEW METHODS: A systematic review was undertaken according to published guidelines. Decision analytic modelling was undertaken, based on the findings of the review, expert opinion and additional information from the literature, to assess the relative cost-effectiveness of plausible alternative tests that are part of diagnostic algorithms for haematuria. RESULTS: A total of 118 studies met the inclusion criteria. No studies that evaluated the effectiveness of diagnostic algorithms for haematuria or the effectiveness of screening for haematuria or investigating its underlying cause were identified. Eighteen out of 19 identified studies evaluated dipstick tests and data from these suggested that these are moderately useful in establishing the presence of, but cannot be used to rule out, haematuria. Six studies using haematuria as a test for the presence of a disease indicated that the detection of microhaematuria cannot alone be considered a useful test either to rule in or rule out the presence of a significant underlying pathology (urinary calculi or bladder cancer). Forty-eight of 80 studies addressed methods to localise the source of bleeding (renal or lower urinary tract). The methods and thresholds described in these studies varied greatly, precluding any estimate of a 'best performance' threshold that could be applied across patient groups. However, studies of red blood cell morphology that used a cut-off value of 80% dysmorphic cells for glomerular disease reported consistently high specificities (potentially useful in ruling in a renal cause for haematuria). The reported sensitivities were generally low. Twenty-eight studies included data on the accuracy of laboratory tests (tumour markers, cytology) for the diagnosis of bladder cancer. The majority of tumour marker studies evaluated nuclear matrix protein 22 or bladder tumour antigen. The sensitivity and specificity ranges suggested that neither of these would be useful either for diagnosing bladder cancer or for ruling out patients for further investigation (cystoscopy). However, the evidence remains sparse and the diagnostic accuracy estimates varied widely between studies. Fifteen studies evaluating urine cytology as a test for urinary tract malignancies were heterogeneous and poorly reported. The calculated specificity values were generally high, suggesting some possible utility in confirming malignancy. However, the evidence suggests that urine cytology has no application in ruling out malignancy or excluding patients from further investigation. Fifteen studies evaluated imaging techniques [computed tomography (CT), intravenous urography (IVU) or ultrasound scanning (US)] to detect the underlying cause of haematuria. The target condition and the reference standard varied greatly between these studies. The diagnostic accuracy data for several individual studies appeared promising but meaningful comparison of the available imaging technologies was impossible. Eight studies met the inclusion criteria but addressed different parts of the diagnostic chain (e.g. screening programmes, laboratory investigations, full urological work-up). No single study addressed the complete diagnostic process. The review also highlighted a number of methodological limitations of these studies, including their lack of generalisability to the UK context. Separate decision analytic models were therefore developed to progress estimation of the optimal strategy for the diagnostic management of haematuria. The economic model for the detection of microhaematuria found that immediate microscopy following a positive dipstick test would improve diagnostic efficiency as it eliminates the high number of false positives produced by dipstick testing. Strategies that use routine microscopy may be associated with high numbers of false results, but evidence was lacking regarding the accuracy of routine microscopy and estimates were adopted for the model. The model for imaging the upper urinary tract showed that US detects more tumours than IVU at one-third of the cost, and is also associated with fewer false results. For any cause of haematuria, CT was shown to have a mean incremental cost-effectiveness ratio of pounds sterling 9939 in comparison with the next best option, US. When US is followed up with CT for negative results with persistent haematuria, it dominates the initial use of CT alone, with a saving of pounds sterling 235,000 for the evaluation of 1000 patients. The model for investigation of the lower urinary tract showed that for low-risk patients the use of immediate cystoscopy could be avoided if cystoscopy were used for follow-up patients with a negative initial test using tumour markers and/or cytology, resulting in a saving of pounds sterling 483,000 for the evaluation of 1000 patients. The clinical and economic impact on delayed detection of both upper and lower urinary tract tumours through the use of follow-up testing should be evaluated in future studies. CONCLUSIONS: There are insufficient data currently available to derive an evidence-based algorithm of the diagnostic pathway for haematuria. A hypothetical algorithm based on the opinion and practice of clinical experts in the review team, other published algorithms and the results of economic modelling is presented in this report. This algorithm is presented, for comparative purposes, alongside current US and UK guidelines. The ideas contained in these algorithms and the specific questions outlined should form the basis of future research. Quality assessment of the diagnostic accuracy studies included in this review highlighted several areas of deficiency.

Algorithms↗
PubMed1997

Comparison of clinical judgment and diagnostic ultrasonography in the diagnosis of acute appendicitis: experience with a score-aided diagnosis.

OBJECTIVE: To evaluate the diagnostic accuracy of clinical judgment and diagnostic ultrasonography (US) used routinely and to create a scoring system to aid diagnosis. DESIGN: Prospective, double-blind study. SETTING: University hospital, Denmark. SUBJECTS: 222 Consecutive patients suspected of having acute appendicitis admitted between 0800 and midnight from June 1990 to June 1992. INTERVENTIONS: 148 Patients (67%) underwent appendicectomy and the remaining 74 patients were observed. 193 Patients (87%) had a diagnostic US examination. 21 Predictive variables were collected prospectively to create a scoring system. MAIN OUTCOME MEASURES: Results of surgical pathological findings, clinical outcome (observed group), diagnostic US, and values of diagnostic score. RESULTS: The decision to operate was made by a junior surgeon solely on the clinical examination, which yielded a diagnostic accuracy of 76%, specificity of 58%, and negative appendicectomy rate of 36%. 193 Patients underwent diagnostic US conducted by the radiologist on call of whom 123 were operated on, 78 for histologically proven appendicitis. US had a diagnostic accuracy of 72%, sensitivity of 49%, and specificity of 88%. Of the 21 predictive factors for acute appendicitis 11 were significant (p < 0.05): total white cell count (WCC) (>10 x 10[9]/1), migration of pain to the right lower quadrant, gradual onset of pain, increasing intensity of pain, pain aggravated by movement, pain aggravated by coughing, anorexia, vomiting, indirect tenderness (Rovsing's sign), muscle spasm, and sex. These 11 predictors were assigned an appropriate weight, based on the likelihood ratio, and used to create a scoring system. The score performed poorly if it was used to separate patients for observation and those for appendicectomy. However, if the score was used with two cut-off points resulting in three test zones (low, intermediate, and high risk of having acute appendicitis), some diagnostic benefit was seen for those patients within the zones of high and low probability. CONCLUSION: The clinical judgment of a junior surgeon was disappointing, and diagnostic aids are desirable to reduce the negative appendicectomy rate. Diagnostic US performed poorly as a routine procedure. Application of an up to date scoring system might be of some help to patients with a high or low probability of acute appendicitis, but any conclusion about its clinical application cannot be drawn from this study.

Acute Disease↗
PubMed2026

Diagnostic communication in functional neurological disorder: A systematic review and meta-analysis of patient acceptance and clinical outcomes.

OBJECTIVES: Diagnostic disclosure is a key therapeutic moment in Functional Neurological Disorder (FND). This systematic review aimed to evaluate quantitative evidence on diagnostic acceptance, understanding, satisfaction, symptom outcomes, and healthcare utilisation following diagnostic disclosure in FND, and to conduct a meta-analysis of diagnostic acceptance. METHODS: Systematic searches of PubMed, Scopus, PsycINFO, and Web of Science identified quantitative studies in adults with FND. Screening followed predefined inclusion criteria. Data were extracted using a structured template and risk of bias was assessed using the Newcastle-Ottawa Scale. A random-effects meta-analysis of proportions was conducted using the Freeman-Tukey transformation. RESULTS: Fifteen studies were included, four of which contributed to the meta-analysis (n&#x202f;=&#x202f;481). Reported diagnostic acceptance rates ranged from 38.7% to 90%, although the timing and method of assessment varied across studies. Pooled acceptance was 0.68 (95% CI 0.44-0.88), with substantial heterogeneity. Structured or reinforced communication was frequently associated with improved understanding and satisfaction, although its superiority for diagnostic acceptance was not established. In some studies, diagnostic acceptance was associated with more favourable clinical outcomes, although findings were inconsistent. Some studies reported reductions in healthcare utilisation or costs following satisfactory diagnostic explanation, whereas others found no sustained overall reduction. CONCLUSIONS: Diagnostic communication in FND is associated with differences in acceptance, understanding, and downstream clinical and healthcare outcomes. Approximately two-thirds of patients were reported as accepting the diagnosis following disclosure, although the timing and method of assessment varied substantially across studies. Empathic and evidence-informed communication may enhance understanding and engagement, although its effects on healthcare use and recovery remain uncertain. PRACTICE IMPLICATIONS: Diagnostic disclosure should be delivered clearly, empathically, and with reinforcement over time. Written information, reputable educational resources, and opportunities for follow-up clarification may support patient understanding and engagement, although stronger comparative evidence is needed.

Humans↗
PubMed1999

Enhancement of clinicians' diagnostic reasoning by computer-based consultation: a multisite study of 2 systems.

CONTEXT: Computer-based diagnostic decision support systems (DSSs) were developed to improve health care quality by providing accurate, useful, and timely diagnostic information to clinicians. However, most studies have emphasized the accuracy of the computer system alone, without placing clinicians in the role of direct users. OBJECTIVE: To explore the extent to which consultations with DSSs improve clinicians' diagnostic hypotheses in a set of diagnostically challenging cases. DESIGN: Partially randomized controlled trial conducted in a laboratory setting, using a prospective balanced experimental design in 1995-1998. SETTING: Three academic medical centers, none of which were involved in the development of the DSSs. PARTICIPANTS: A total of 216 physicians: 72 at each site, including 24 internal medicine faculty members, 24 senior residents, and 24 fourth-year medical students. One physician's data were lost to analysis. INTERVENTION: Two DSSs, ILIAD (version 4.2) and Quick Medical Reference (QMR; version 3.7.1), were used by participants for diagnostic evaluation of a total of 36 cases based on actual patients. After training, each subject evaluated 9 of the 36 cases, first without and then using a DSS, and suggested an ordered list of diagnostic hypotheses after each evaluation. MAIN OUTCOME MEASURE: Diagnostic accuracy, measured as the presence of the correct diagnosis on the hypothesis list and also using a derived diagnostic quality score, before and after consultation with the DSSs. RESULTS: Correct diagnoses appeared in subjects' hypothesis lists for 39.5% of cases prior to consultation and 45.4% of cases after consultation. Subjects' mean diagnostic quality scores increased from 5.7 (95% confidence interval [CI], 5.5-5.9) to 6.1 (95% CI, 5.9-6.3) (effect size: Cohen d = 0.32; 95% CI, 0.23-0.41; P<.001). Larger increases (P = .048) were observed for students than for residents and faculty. Effect size varied significantly (P<.02) by DSS (Cohen d = 0.20; 95% CI, 0.08-0.32 for ILIAD vs Cohen d = 0.45; 95% CI, 0.31-0.59 for QMR). CONCLUSIONS: Our study supports the idea that "hands-on" use of diagnostic DSSs can influence diagnostic reasoning of clinicians. The larger effect for students suggests a possible educational role for these systems.

Decision Support Techniques↗
PubMed2002

Performance evaluation of an 85-cm-bore X-ray computed tomography scanner designed for radiation oncology and comparison with current diagnostic CT scanners.

INTRODUCTION: The demand for computed tomography (CT) virtual simulation is constantly increasing with the wider adoption of three-dimensional conformal and intensity-modulated radiation therapy. Virtual simulation CT studies are typically acquired on conventional diagnostic scanners equipped with an external patient positioning laser system and specialized planning and visualization software. Virtual simulation technology has matured to a point where conventional simulators may be replaced with CT scanners. However, diagnostic CT scanner gantry bores (typically 65-70 cm) can present an obstacle to the CT simulation process by limiting patient positions, compared to those that can be attained in a conventional simulator. For example, breast cancer patients cannot always be scanned in the treatment position without compromising reproducibility and appropriateness of setup. Extremely large patients or patients requiring special immobilization or large setup devices are often unable to enter the limited-bore gantry. A dedicated 85-cm-bore radiation oncology CT scanner has the potential to eliminate these problems. The scanner should provide diagnostic-quality images at diagnostic-comparable dose levels. The purpose of this study was to independently evaluate the performance of a novel 85-cm-bore CT X-ray scanner designed specifically for radiation oncology and compare it against diagnostic-type, 70-cm-bore scanners that may be used in the same setting. MATERIALS AND METHODS: We performed image quality and dosimetric measurements on an 85-cm-bore CT scanner (AcQSim CT, Marconi Medical Systems, Inc., Cleveland, OH) and a 70-cm-bore, diagnostic-type scanner (UltraZ CT, Marconi Medical Systems, Inc.). Image quality measurements were performed using a manufacturer-supplied phantom (Performance Phantom, Marconi Medical Systems, Inc.), following the manufacturer's suggested testing procedures, and an independent image quality phantom (CATPHAN 500, The Phantom Laboratory, New York, NY). The standard image quality parameters evaluated for the purpose of comparison were as follows: slice thickness accuracy, high-contrast resolution (limiting spatial resolution), low-contrast resolution, uniformity and noise, and CT number accuracy and linearity. Standard head and body protocols were employed throughout most of our measurements and were kept equal between the two scanners. The computed tomography dose index was measured for standard head and body imaging protocols using accepted methods and procedures. For comparison purposes, data for a diagnostic-type, 70-cm-bore scanner (GE HighSpeed CT/i) were extracted from the literature. The results obtained for the 85-cm-bore scanner are compared with the following: (1) manufacturer-provided autoperformance phantom test results (validating its use for routine quality assurance), (2) a similar set of measurements performed on a conventional 70-cm-bore, diagnostic-type CT scanner (UltraZ CT, Marconi Medical Systems, Inc.), and (3) current available data on other diagnostic-type CT scanners (GE HighSpeed CT/i). RESULTS: Head and body doses seem on average to be slightly (1-2 cGy) higher for the 85-cm-bore unit than for conventional 70-cm units. Measured slice thickness was within acceptable criteria, +/-0.5 mm. There does not seem to be any significant difference in high-contrast resolution. Both units render a limiting value of approximately 7-8 lp/cm for slice thickness 8-10 mm. Both units exhibit comparable CT number uniformity, accuracy, and linearity. Noise levels seem to be slightly increased (by approximately 0.05-0.2%) for the large-bore geometry. Low-contrast resolution for both units was comparable (4.5-5.5 mm @ 0.35%). All image quality parameters are well within diagnostic acceptable levels. CONCLUSION: The overall imaging performance and mechanical integrity of the 85-cm-bore scanner are comparable to those of conventional diagnostic scanners that may be employed in a radiation oncology setting.

Computer Simulation↗
PubMed2000

Diagnostic value of tachycardia features and pacing maneuvers during paroxysmal supraventricular tachycardia.

OBJECTIVES: The purpose of this prospective study was to quantitate the diagnostic value of several tachycardia features and pacing maneuvers in patients with paroxysmal supraventricular tachycardia (PSVT) in the electrophysiology laboratory. BACKGROUND: No study has prospectively compared the value of multiple diagnostic tools in a large group of patients with PSVT. METHODS: One hundred ninety-six consecutive patients who had 200 inducible sustained PSVTs during an electrophysiology procedure were included. The diagnostic values of four baseline electrophysiologic parameters, nine tachycardia features and five diagnostic pacing maneuvers were quantified. RESULTS: The only tachycardia characteristic that was diagnostic of atrioventricular (AV) nodal reentry was a septal ventriculoatrial (VA) time of <70 ms, and no pacing maneuver was diagnostic for AV nodal reentry. An increase in the VA interval with the development of a bundle branch block was the only tachycardia characteristic that was diagnostic for orthodromic tachycardia, but it occurred in only 7% of all tachycardias. An atrial-atrial-ventricular response upon cessation of ventricular overdrive pacing was diagnostic of atrial tachycardia, and this maneuver could be applied to 78% of all tachycardias. Burst ventricular pacing excluded atrial tachycardia when the tachycardia terminated without depolarization of the atrium, but the result could be obtained only in 27% of patients. CONCLUSIONS: This prospective study quantitates the diagnostic value of multiple observations and pacing maneuvers that are commonly used during PSVT in the electrophysiology laboratory. The findings demonstrate that diagnostic techniques rarely provide a diagnosis when used individually. Therefore, careful observations and multiple pacing maneuvers are often required for an accurate diagnosis during PSVT. The results of this study provide a useful reference with which new diagnostic techniques can be compared.

Adolescent↗
PubMed1997

The agreement among urological experts on the diagnostic management of patients with common urological problems.

OBJECTIVE: To assess the level of agreement among randomly selected international urologists on the diagnostic management of patients with prostate cancer, bladder cancer, urinary stones or lower urinary tract symptoms (LUTS) arising from benign prostatic hyperplasia (BPH). METHODS: A computer program was used to provide an unbiased format of 53 simulated patients, comprising 13 with prostate cancer, 10 with bladder cancer, 10 with stones in the upper urinary tract and 20 with LUTS from BPH. For each case, the history was provided to the user while information from 60 diagnostic tests could be chosen interactively. Thirty-three university-based urologists participated in the study. The probability that a certain test was used by them in a certain patient [P(test)] and the related costs (Swedish 1995 prices) were recorded. The probability that two urologists would agree (relative measure of agreement, RMA) on whether or not to use one particular test in a certain case was RMA(test) = P(test)2 + [1-P(test)]2 and the mean of this RMA(test) for a certain patient [RMA(case)] was used as a measure of the inter-individual agreement among the urologists on the diagnostic management. The significance levels of the generalized kappa statistic, KG, were also calculated. The correlation between the RMA(case) and the diagnostic groups was analysed. RESULTS: The KG was statistically significant for all cases; the RMA(case) was significantly correlated with the diagnostic groups (rs = 0.86). The agreement in the diagnostic management was the strongest for stones, then for bladder cancer and prostate cancer, and the weakest for BPH. The mean cost for the diagnostic evaluation for one case varied from $455 to $1771 (mean 898) and varied in the diagnostic groups, i.e. $1718 for prostate cancer, $947 for bladder cancer, $400 for stones and $594 for BPH. CONCLUSION: The diagnostic management of urological patients varies greatly among urological experts from the industrial world. As a consequence, the related diagnostic costs might vary by about 400% if prices were similar everywhere. The agreement on the diagnostic management of cases is strongly correlated to the diagnosis. LUTS from BPH seems to be managed with the poorest agreement.

Attitude of Health Personnel↗
PubMed2004

[Optimised neuro-psychological tests on different stages of dementia diagnostics].

OBJECTIVE: We postulated three level of dementia diagnostics: the general practitioner, the neuro-psychiatrist and the memory clinic. For each level, definite diagnostic questions were defined as the main diagnostic focus. The aim was to establish a staged process in dementia diagnostics, proposing for each diagnostic level a specific test battery suitable for the respective diagnostic focus. On each level, the test battery can be supplemented by other tests proposed on the subsequent diagnostic level. METHOD: 159 patients were examined clinically, neuropsychologically, and neuroradiologically. Discriminant analyses were computed to find out which tests out of a comprehensive test battery are most suitable in differentiating between several diagnostic groups. RESULTS: The diagnostic accuracy of the test batteries proposed for general practitioners and neuro-psychiatrists were maximally 3 % below that of the complete test battery which we suggest for memory clinics. CONCLUSION: Depending on the diagnostic level, a definite short form of a comprehensive test battery can be implemented without unacceptably reducing diagnostic accuracy.

Aged↗
PubMed2004

Non-diagnostic cytological outcome of thyroid biopsy and the risk of thyroid malignancy.

This study assessed the incidence of neoplasms, including malignant tumors, in lesions within the thyroid gland from which non-diagnostic biopsy aspirates were obtained. An auxiliary goal of the study was an evaluation of the diagnostic efficacy of repeated biopsy in cases when the first biopsy was non-diagnostic. Thus, results of 4603 fine-needle aspiration biopsies (FNABs) were submitted to histopathological verification. The verification revealed the rate of malignancy at 7.1% for non-diagnostic biopsies, i.e., significantly higher (p < 0.001) than that in cases FNAB-diagnosed as benign lesions (2.1%). Repeated biopsy, performed when inadequate material has been collected, seems to be less effective than the first biopsy (non-diagnostic specimens: 14.4% vs 8.9%; p < 0.01). The occurrence of neoplasms in the goiter was significantly higher (p < 0.0001) in patients with non-diagnostic first FNAB than in those with diagnostic one (50.7% vs 33.5%, p < 0.001). And again, in patients with two non-diagnostic FNABs, the occurrence of neoplasms was higher than that in patients with the second diagnostic cytology (63% vs 41.2%, p < 0.05). According to our data, patients with non-diagnostic FNAB results should be very carefully monitored, especially when the repeated biopsy is either non-diagnostic again or not performed at all.

Biopsy, Fine-Needle↗