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At least 1,081 records · Page 60Linked to original sources
PubMed2005

Diagnostic testing of vitrectomy specimens.

PURPOSE: To assess the usefulness of diagnostic tests that are performed on vitrectomy specimens from patients with suspected lymphoma or infection. DESIGN: Noncomparative, retrospective, interventional case series. METHODS: Seventy-eight consecutive patients (84 eyes) underwent pars plana vitrectomy for diagnostic purposes. Vitrectomy with cytologic, cytofluorographic, or microbiologic analysis of vitreous samples was performed. The main outcome measures were the efficiency of diagnostic procedure and positive and negative predictive values (PPV and NPV). RESULTS: There were 28 patients (33 eyes) with suspected intraocular lymphoma and 50 patients (51 eyes) with suspected infection, which was subdivided into chronic endogenous endophthalmitis, atypical chorioretinitis, or chronic postoperative inflammation. Vitreous testing led to a diagnosis in 48 of 78 patients (61.5%); 14 patients with a final diagnosis of lymphoma/leukemia, and 34 patients with a final diagnosis of infection. When preoperative indication was compared with final clinical diagnosis, the efficiency of the diagnostic procedure of cytologic evaluation, flow cytometry, and bacterial/fungal culture was 67%, 79%, and 96%, respectively. For lymphoma, the PPV of cytologic evaluation was 100% and the NPV 60.9%. For infection, the PPV of bacterial/fungal culture was 100% and the NPV 94.9%. CD22+ B lymphocytes >or=20% of total cells on cytofluorographic analysis had a PPV of 88% for lymphoma. A cytofluorographic CD4:CD8 T-lymphocyte ratio >or=4 had a PPV of 70% for immunologically mediated uveitis. Surgical complications were rare and manageable. CONCLUSION: Diagnostic vitrectomy in selected patients with carefully planned testing is an effective means of supporting diagnoses in intraocular lymphoma, chronic intraocular infections, and atypical chorioretinitis. Flow cytometry quantitates the percentages and ratios of various cell types and is helpful in contrasting intraocular lymphoma with immunologically mediated uveitis.

Adult↗
PubMed2005

Clinical impact of molecular diagnostics in low-grade lymphoma.

Molecular diagnostics in low grade B cell lymphoma is currently based on polymerase chain reaction (PCR) detection of lymphoid clonality or of molecular (onco)genetic markers that result from chromosomal translocations. The former is based on detection of clonal immunoglobulin (Ig) and/or T cell receptor (TCR) rearrangements, which can be used for distinguishing between malignant and reactive lymphoproliferation, for staging, for comparison of diagnostic and relapse material and for minimal residual disease assessment. Informativity has risen with the development of improved, standardised DNA-based Ig/TCR strategies but remains dependent on tumour subtype, largely as a function of the rate of IgH somatic mutation. PCR-based detection of molecular genetic markers can aid diagnosis, although genetic breakpoint heterogeneity and low level molecular informativity means that alternative techniques, such as fluorescent in situ hybridisation or immunohistochemistry of the deregulated genes, can be preferable. Appropriate molecular diagnostic practise is entirely dependent on the conservation of appropriate material, with the increasing tendency for RNA based diagnostics, particularly for transcriptional profiling, rendering tissue banking of unfixed material extremely important. Therapeutic stratification of patients with low grade lymphoma is likely to be increasingly based on multiparameter genetic and/or immunological analysis, with monoparameter targets being reserved for follow-up. Appropriate use of the increasing number of analytical techniques available is best applied in specialised diagnostic platforms with a complementary, interdisciplinary approach that can be adapted to the clinical situation.

Clone Cells↗
PubMedDate not supplied

A latent structure analysis of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Narcissistic Personality Disorder criteria.

The aim of this study was to examine the latent structure of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), Narcissistic Personality Disorder (NPD) criteria in a group of 641 outpatients. The consecutively admitted outpatients were administered the Structured Clinical Interview for DSM-IV Axis II Personality Disorders, Version 2.0, and the Personality Questionnaire. Both confirmatory and exploratory factor analyses (CFA and EFA, respectively) were used to evaluate whether the NPD criteria measure a single latent trait. Latent class analysis was used to assess the diagnostic accuracy of the individual DSM-IV NPD criteria. Mean above minus below a cut (MAMBAC) and maximum covariance (MAXCOV) taxometric analyses were used to evaluate whether the latent distribution of the DSM-IV NPD features is actually discrete. Both CFA and EFA results showed that the 9 DSM-IV NPD criteria loaded on 2 correlated factors. The latent class analysis results suggested a 3-class solution for NPD criteria; relevant differences in diagnostic efficiency were observed among the NPD criteria. MAMBAC and MAXCOV analyses provided consistent evidence of taxonic (ie, discrete) latent structure for NPD. This study gave only partial support to the validity of the DSM-IV NPD construct. Taxometric analyses indicated that a typological model is appropriate for describing NPD, but CFA and EFA suggested the existence of 2 distinct-albeit correlated-clusters of narcissistic features. As a whole, the DSM-IV criteria discriminated NPD from other personality disorders, but diagnostic accuracy statistics did not replicate the rank order of diagnostic efficiency of NPD criteria proposed by the DSM-IV.

Adult↗
PubMed2026

Diagnostic accuracy of bronchoalveolar lavage fluid-based testing for pulmonary cryptococcosis: A systematic review and meta-analysis.

BACKGROUND: Pulmonary cryptococcosis(PC) presents diagnostic challenges because of its non-specific clinical and radiological manifestations. Bronchoalveolar lavage fluid (BALF)-based testing, which includes latex agglutination (LA) and lateral flow assay (LFA), offers a minimally invasive diagnostic method, yet its pooled diagnostic accuracy remains unclear. METHODS: We systematically searched PubMed, Embase, Cochrane Library, and Scopus from inception to May 2026. Studies evaluating BALF-based testing for PC with extractable 2 × 2 data were included. The methodological quality of relevant studies was assessed by the QUADAS-2 tool. Pooled sensitivity, specificity, likelihood ratios, and diagnostic odds ratio (DOR) were estimated using a bivariate random-effects model. Subgroup analyses were performed by testing method and reference standard type. Heterogeneity was evaluated through paired forest plots, HSROC visualization, and exploratory bivariate meta-regression. RESULTS: The pooled sensitivity was 0.87 (95% CI: 0.81-0.91), and the specificity was 0.99 (95% CI: 0.982 - 0.995). The pooled positive likelihood ratio (PLR) was 88.00 (95% CI: 47.39 - 163.42), the negative likelihood ratio (NLR) was 0.13 (95% CI: 0.09 -0.20), and the DOR was 658.50 (95% CI: 285.36-1519.55). No significant threshold effect or publication bias was detected. Exploratory meta-regression suggested a possible assay-method effect in the joint model (P = 0.03), mainly driven by specificity (P = 0.01). CONCLUSIONS: The study demonstrates the high accuracy of CrAg in BALF for the diagnosis of pulmonary cryptococcosis, supporting its role as an important adjunctive diagnostic tool, particularly when tissue biopsy is not feasible or rapid results are needed. Larger prospective studies with standardized protocols are needed to validate these estimates.

Humans↗
PubMed2025

A meta-analysis of diagnostic yield and clinical utility of genome and exome sequencing in pediatric rare and undiagnosed genetic diseases.

PURPOSE: To systematically evaluate the diagnostic yield and clinical utility of genome sequencing (GS) and exome sequencing (ES; genome-wide sequencing [GWS]) in pediatric patients with rare and undiagnosed genetic diseases. METHODS: We conducted a meta-analysis of studies published between 2011 and 2023. To address study heterogeneity, comparative analyses included within-cohort studies using random-effects models. RESULTS: We identified 108 studies including 24,631 probands with diverse clinical indications. The pooled diagnostic yield among within-cohort studies (N = 13) for GWS was 34.2% (95% CI: 27.6-41.5; I2: 86%) vs 18.1% (95% CI: 13.1-24.6; I2: 89%) for non-GWS, with 2.4-times odds of diagnosis (95% CI: 1.40-4.04; P < .05). The pooled diagnostic yield among within-cohort studies (N = 3) for GS was 30.6% (95% CI: 18.6-45.9; I2: 79%) vs 23.2% (95% CI: 18.5-28.7; I2: 58%) for ES, with 1.7-times the odds of diagnosis (95% CI: 0.94-2.92; P = .13). In first-line testing, the diagnostic yield tended to be higher for GS than for ES across clinical subgroups. The pooled clinical utility among patients with a positive diagnosis was 58.7% (95% CI: 47.3-69.2; I2: 81%) for GS and 54.5% (95% CI: 40.7-67.6; I2: 87%) for ES. CONCLUSION: GS appears to have a higher diagnostic yield than ES, with similar clinical utility per positive diagnosis.

Child↗
PubMed2005

A systematic review finds that diagnostic reviews fail to incorporate quality despite available tools.

BACKGROUND AND OBJECTIVE: To review existing quality assessment tools for diagnostic accuracy studies and to examine to what extent quality was assessed and incorporated in diagnostic systematic reviews. METHODS: Electronic databases were searched for tools to assess the quality of studies of diagnostic accuracy or guides for conducting, reporting or interpreting such studies. The Database of Abstracts of Reviews of Effects (DARE; 1995-2001) was used to identify systematic reviews of diagnostic studies to examine the practice of quality assessment of primary studies. RESULTS: Ninety-one quality assessment tools were identified. Only two provided details of tool development, and only a small proportion provided any indication of the aspects of quality they aimed to assess. None of the tools had been systematically evaluated. We identified 114 systematic reviews, of which 58 (51%) had performed an explicit quality assessment and were further examined. The majority of reviews used more than one method of incorporating quality. CONCLUSION: Most tools to assess the quality of diagnostic accuracy studies do not start from a well-defined definition of quality. None has been systematically evaluated. The majority of existing systematic reviews fail to take differences in quality into account. Reviewers should consider quality as a possible source of heterogeneity.

Bias↗
PubMed2006

Validation of molecular-diagnostic techniques in the parasitological laboratory.

Diagnostic laboratories today often operate according to standard quality management procedures such as ISO/IEC 17025. This requires that only validated methods are used. Validation procedures help to document that a particular protocol used by the accredited laboratory has a guaranteed performance in that particular laboratory. Several study designs exist for validation procedures. Computer programmes are available to help with the statistical analysis of validation results. The agreement beyond chance of results obtained in the protocol that is to be validated can be compared to those achieved in an already established test (agreement). For a method that is used under routine conditions or for epidemiological studies, it is necessary to assess the diagnostic sensitivity and diagnostic specificity of the technique. These parameters can be estimated by comparing the method that needs to be validated with an existing reliable method ('gold standard'). This is done by testing a standard set of well-documented samples using both techniques in parallel. Approaches using Bayes' theorem are used to perform gold standard-free validations. Many PCR-based methods are characterised by an excellent analytical sensitivity and are thus good candidates for diagnostic tools of the required diagnostic sensitivity. However, the high level of analytical sensitivity can also make molecular techniques susceptible to cross-contamination and carry-over problems leading to false-positive results. Moreover, the presence of inhibitors can cause false-negative results. After an initial validation, test performance needs to be continuously monitored, e.g. by using combined Shewhart-CUSUM control routines, and test results compared to those obtained by other laboratories (proficiency testing).

Animals↗
PubMed1999

Underuse and overuse of diagnostic testing for coronary artery disease in patients presenting with new-onset chest pain.

PURPOSE: To determine the extent of overuse and underuse of diagnostic testing for coronary artery disease and whether the socioeconomic status, health insurance, gender, and race/ethnicity of a patient influences the use of diagnostic tests. SUBJECTS AND METHODS: We identified patients who presented with new-onset chest pain not due to myocardial infarction at one of five Los Angeles-area hospital emergency departments between October 1994 and April 1996. Explicit criteria for diagnostic testing were developed using the RAND/University of California, Los Angeles, expert panel method. They were applied to data collected by medical record review and patient questionnaire. RESULTS: Of the 356 patients, 181 met necessity criteria for diagnostic cardiac testing. Of these, 40 (22%) failed to receive necessary tests. Only 7 (3%) of the 215 patients who received some form of cardiac testing had tests that were judged to be inappropriate. Underuse was significantly more common in patients with only a high school education (30% vs 15% for those with some college, P = 0.02) and those without health insurance (34% vs 15% of insured patients, P = 0.01). In a multivariate logistic regression model, only the lack of a post-high school education was a significant predictor of underuse (odds ratio 2.2, 95% confidence interval 1.0 to 4.4). CONCLUSION: Among patients with new-onset chest pain, underuse of diagnostic testing for coronary artery disease was much more common than overuse. Underuse was primarily associated with lower levels of patient education.

Adult↗
PubMed2003

Set theory in diagnostic reasoning.

BACKGROUND: Regarding diagnostic reasoning, the currently taught Bayesian theory is a form of hypothetical-deduction reasoning. Using set theory, we offer syllogism reasoning instead of hypothetical-deductive reasoning and establish an online diagnostic expert system model based on this diagnostic methodology. METHODS: Concepts of set theory were employed to demonstrate diagnostic reasoning. ASP, Vbscript and Microsoft Access were used to establish the expert system and data of 50 cases from Shanghai pulmonary hospital were put into the program to test its efficiency. CONCLUSION: Diagnostic procedure is type of syllogism rather than hypothetical-deductive reasoning.

Cluster Analysis↗
PubMed2001

Evaluation of the diagnostic workup in young women referred for recurrent lower urinary tract infections.

OBJECTIVES: To evaluate the current practice of the diagnostic workup in The Netherlands and the clinical relevancy of the outcome of various diagnostic procedures in young women referred for recurrent lower urinary tract infections (UTIs). METHODS: A questionnaire was sent to all urologic departments in The Netherlands (n = 104) inquiring about the diagnostic procedures used for recurrent lower UTIs. Furthermore, we performed a prospective study in 100 consecutive young female patients (18 to 40 years old) referred for evaluation of recurrent lower UTIs. All patients underwent a standardized workup: questionnaire, voiding diary, physical examination, urinalysis and culture, abdominal x-ray with ultrasound or intravenous urography, and cystoscopy. RESULTS: The response rate to the questionnaires was 92%. The standard procedures were laboratory blood tests in 56%, cystoscopy in 69%, plain abdominal x-ray in 91%, and abdominal ultrasound in 59%. Only 18% of the urologists asked every patient to make a voided urine frequency volume chart. In our group of patients, the radiologic procedures revealed only one relevant abnormality. Cystoscopy confirmed cystitis in 22 patients, but never revealed relevant findings. None of these diagnostic procedures ever contributed to the diagnosis. The 24-hour urine output was less than 1.5 L in 43 patients, which was considered insufficient. The individual self-reports of fluid intake were unreliable. CONCLUSIONS: Many Dutch urologists perform an extensive routine workup in patients referred for recurrent lower UTIs. The results of our study revealed that the yield of most diagnostic procedures in these patients is low. The focus in evaluating these patients should be directed toward the behavioral aspects. Thus, the routine workup can be restricted to a voiding diary, urinalysis, and urine culture.

Adolescent↗
PubMed1996

The use of standard imaging techniques and their diagnostic value in the workup of renal colic in the setting of intractable flank pain.

OBJECTIVES: This study reviews the rate at which diagnostic imaging techniques are used in patients with intractable flank pain attributed to renal colic who are admitted to the hospital through the emergency room and determines the diagnostic values of plain film of the abdomen {kidney, ureter, bladder [KUB]} and of ultrasonography (US) of the urinary tract, using intravenous urography (IVU) as the gold standard for establishing the presence of a calculus. METHODS: We reviewed the medical records of 288 patients who were admitted to our medical center over a period of 5 consecutive years for intractable flank pain, the admission and working diagnosis in all cases being that of renal colic, and we retrieved all data pertaining to their diagnostic evaluation. RESULTS: A total of 265 patients (92%) were subjected to KUB, 158 (55%) to IVU, and 135 (45%) to US of the renal-urinary tract. Two diagnostic imaging techniques were used in the same patient in the following combinations: KUB and IVU in 146 patients (51%), KUB and US in 110 (38%), and IVU and US in 60 (21%). Three imaging techniques (IVU, KUB, and US) were utilized in 54 patients (19%). The sensitivity and specificity of KUB alone were 95% and 65%, respectively, and the positive and negative predictive values were 82% and 88%. The sensitivity of US alone was 93%, its specificity 83%, the positive predictive value 93%, and the negative predictive value 83%. The sensitivity of combined KUB and US (requiring both tests to be positive for diagnosing the presence of a calculus) was 89%, the specificity 100%, the positive predictive value 100%, and the negative predictive value 81%. CONCLUSIONS: Our data indicate that combining US with KUB provides the best diagnostic algorithm that approaches the yield of IVU in excluding the presence of a calculus in the renal-urinary tract in patients who present with intractable flank pain.

Algorithms↗
PubMed2003

Understanding and using diagnostic tests.

Every diagnostic test causes additional cost if not additional risk. The cost and risk are justified if the test result is likely to change what is done for patients. This includes a diagnostic test that does not alter therapy but provides important prognostic information for the parents. Whether the test result changes therapy depends on: the action threshold (the probability of disease at which the clinician offers the therapy or intervention because it would do more good than harm). the patient's pretest probability of disease. the test performance (measured by LRs, sensitivity, and specificity). For all tests there is an inverse relationship or trade-offbetween sensitivity and specificity. A good diagnostic test is one in which this trade-off is relatively small within the range of sensitivities and specificities that are clinically relevant. When diagnostic tests are used in low-risk subjects (as in screening tests), the performance of the test is critical because missing a significant number of cases is considered unacceptable and subjecting healthy individuals to the repercussions of false-positive test results is also problematic. The decision to introduce a screening program also depends on the availability and cost of screening and diagnostic tests, the potential for testing to cause harm, the prevalence and prognosis of the condition, the availability of effective treatment, and the importance of presymptomatic treatment.

Diagnostic Tests, Routine↗
PubMed2001

Costeffectiveness of diagnostic tests.

We review the principles underlying cost-effectiveness analysis of diagnostic tests and procedures. We use two clinical examples, diagnostic testing for early multiple sclerosis and for Helicobacter pylori to illustrate the methods of analysis and to show how the results can be useful for physicians or payers of health services in making decisions about provision and use of diagnostic services. Economic assessments of diagnostic tests are inherently more difficult than assessments of therapeutic interventions, mainly because of uncertainty about the relation between diagnosis and end results (outcomes) of care. Nonetheless, because of the increasing importance of diagnostic technology in medicine and healthcare, only with such assessments will the most value be gained from restricted medical resources.

Cost-Benefit Analysis↗
PubMed2000

Epidemiologic issues in the validation of veterinary diagnostic tests.

In this review, we critically discuss the objectives, methods and limitations of different approaches for the validation of diagnostic tests. We show (based on published data and our own experiences) that estimates for the diagnostic sensitivity and specificity may vary among populations and/or subpopulations of animals, conditional on the distribution of influential covariates. Additional variability in those parameter estimates may be attributable to the sampling strategy. The uncertainty about diagnostic parameters is of concern for the decision-maker in the context of clinical diagnosis or quantitative risk assessment as well as for the epidemiologist who uses test data for prevalence estimation or risk-factor studies. Examples for the calculation of diagnostic parameters are presented together with bias-avoidance strategies. We suggest guidelines for an epidemiologic approach to test validation of veterinary diagnostic tests.

Animal Diseases↗
PubMed1998

Subtle presentations of post-traumatic stress disorder. Diagnostic issues.

The authors present a set of diagnostic procedures designed to detect subtle presentations of post-traumatic stress disorder (PTSD). Defined as a Type II diagnostic error (a false negative), the authors examine several sources of subtle presentations of PTSD. These include imperfect diagnostic instruments, high base rates, imperfect memory of critical events, imperfect reporting of signs and symptoms, imperfect interpretation of presented signs and symptoms, and diagnostic decisions based on informal clinical judgment. The authors believe that a multistage diagnostic procedure, using instruments with known psychometric properties while simultaneously looking for converging evidence is the best safeguard against missing an appropriate diagnosis of post-traumatic stress disorder.

Data Interpretation, Statistical↗
PubMed1996

Diagnostic approach to exercise intolerance in racehorses.

The diagnostic approach to the exercise intolerant racehorse depends on sound, fundamental steps to allow complete examination of the entire horse in a logical, time-efficient fashion. Availability of referral diagnostic modalities should not overshadow the need for collecting a clinical history or performing a complete physical examination. The diagnostic approach to exercise intolerance can be divided into a few basic steps. The first step, conducted without the horse, is a thorough discussion about the horse with the trainer and/or owner. Many clinical histories are complex and therefore following a predetermined pattern is helpful. Racing ability, general health history, historic problems with the major body systems including the musculoskeletal, respiratory, cardiovascular, and neurologic systems should be reviewed. The next step of the examination is conducted in the stall. A complete physical examination is required. The practitioner should pay close attention to the body systems that most frequently harbor causes of exercise intolerance. Before evaluating the horse for lameness, endoscopy of the upper airway should be performed. The final step is conducted outside the stall: completion of the lameness and neurologic examination or an exercise trial followed by further diagnostic tests such as a serum chemistry profile, bronchoalveolar lavage, or imaging studies. Decision for referral is best made after the physical examination is completed and capability for further diagnostics is exhausted.

Animals↗
PubMed2003

Assessment of the accuracy of diagnostic tests: the cross-sectional study.

In diagnostic accuracy studies, the contrast of interest can be one of the following: one single test contrast; comparing two or more single tests; further testing in addition to previous diagnostics; and comparing alternative diagnostic strategies. The clinical diagnostic problem under study must be specified. Studies of "extreme contrasts" (as early phase evaluations) and studies in "clinical practice" settings (assessing clinical value) should be distinguished. Design options are (1) survey of the total study population, (2) case-referent approach, or (3) test-based enrollment. Data collection should generally be prospective, but ambispective and retrospective approaches are sometimes appropriate. In addition to determinants of primary interest [the test(s) under study] possible modifiers of test accuracy and confounding variables must be specified. The reference standard procedure should be independent from the test results. Applying a reference standard can be difficult in case of classification errors, lack of a clear pathophysiologic concept, incorporation bias, or invasive or complex investigations. Possible solutions are: an independent expert panel, and the delayed type cross-sectional study (clinical follow-up). Also, a prognostic criterion can be chosen. For studies to be relevant for practice, inclusion criteria must be based on "intention to diagnose" or "intention to screen." The recruitment procedure is preferably a consecutive series of presenting patients or a target population screening, respectively. Sample size estimation should be routine. Analysis has to be focused on the contrast of interest. Estimating test accuracy and prediction of outcome need different approaches. External (clinical) validation requires repeated studies in other, similar populations. Also, systematic reviews and meta-analysis have a role. To enable readers of diagnostic research reports to evaluate whether methodological key issues were addressed, authors are advised to follow the STARD guidelines.

Cross-Sectional Studies↗
PubMed2003

Is terminology used effectively to convey diagnostic certainty in radiology reports?

RATIONALE AND OBJECTIVES: This study was performed to assess the extent of agreement among radiologists and nonradiologists in perception of diagnostic certainty conveyed by words and phrases commonly used in radiology reports. MATERIALS AND METHODS: The study was performed in a large academic radiology department. To determine the commonly used terminology for conveying diagnostic certainty in radiology reports, 12 randomly selected radiologists from six different subspecialties were interviewed. The authors identified the 15 most commonly used words and phrases and included these in random order in a questionnaire sent to all staff radiologists (n = 45) and to 158 referring physicians. Physicians were asked to rank the 15 phrases in order of the diagnostic certainty conveyed by each, from 1 (most certain) to 15 (least certain), using each number only once. The kappa statistic was used to assess agreement in rank order among physicians. RESULTS: The questionnaire response rate was 76% (n = 34) for radiologists and 49% (n = 78) for nonradiologists. There was excellent agreement among radiologists (kappa = 0.95) and nonradiologists (kappa = 0.93) in the rank order for the phrase diagnostic of. Although there was good agreement (kappa = 0.45) among radiologists for the word unlikely, agreement among nonradiologists was poor (kappa = 0.27). There was very poor agreement among all physicians for the rank order of the other 13 phrases. CONCLUSION: Among radiologists and nonradiologists, concordance was poor regarding the diagnostic certainty associated with phrases commonly used in radiology reports. Because poor agreement could lead to suboptimal quality of care, the standardization of terminology would benefit all parties.

Diagnostic Techniques and Procedures↗