我国布鲁氏菌病诊断方法应用及思考

布鲁氏菌病是一个全球的公共卫生问题,其诊断方法的研究仍然是热点领域之一。本文将对中国、美国和WHO布鲁氏菌病诊断标准进行比较。对我国目前布鲁氏菌病的主要检测方法及现阶段分子生物学检测进展进行阐述,并对各种诊断方法的特点进行比较。虽然我国已经建立了较完整的诊断体系,但是到目前为止仍没有一种既简单又快速,且灵敏度和特异度都很高的检测方法,这需要进一步研究,为以后完善我国布鲁氏菌病诊断标准提供科学依据。     

Sensitivity and specificity of diagnostic tests in acute maxillary sinusitis determined by maximum likelihood in the absence of an external standard

This study shows how to obtain maximum likelihood estimates of test sensitivities and specificities in case of lack of an external standard, using the Expectation Maximisation (EM) algorithm. This method is used to compare four diagnostic tests in patients suspected of acute maxillary sinusitis. Data were analyzed from published studies. Antral aspiration is the test with the highest diagnostic value. The diagnostic value of a positive clinical examination (according to explicit criteria) and of a positive radiograph or ultrasound are comparable. A negative radiograph is of more diagnostic value than a negative clinical examination or ultrasound. The width of the confidence intervals may be too small, due to model deviations which may give incorrect standard errors. However, the estimated likelihood ratios adequately reflect the relative value of the diagnostic tests considered, even when the assumption of independence is dropped.     

A survey of policies and procedures on the communication and documentation of radiologic interpretations

Research into emergency medicine (EM) diagnostic errors identified imaging as a contributing factor in 94% of cases. Discrepancies between the preliminary (trainee) and the final (attending) diagnostic imaging interpretation represent a system issue that is particularly prone to creating diagnostic errors. Understanding the types of systematic communication and documentation strategies developed by academic radiology departments to address differences between preliminary and final radiology interpretations to clinicians are threshold steps toward minimizing this risk. This study investigates policies and practices associated with the communication and documentation of preliminary and final radiologic interpretations among U.S. academic radiology departments through a questionnaire directed at radiology department chairs.     

Corporal diagnostic work and diagnostic spaces: clinicians’ use of space and bodies during diagnosis

An emerging body of literature in sociology has demonstrated that diagnosis is a useful focal point for understanding the social dimensions of health and illness. This article contributes to this work by drawing attention to the relationship between diagnostic spaces and the way in which clinicians use their own bodies during the diagnostic process. As a case study, we draw upon fieldwork conducted with a multidisciplinary clinical team providing deep brain stimulation (DBS) to treat children with a movement disorder called dystonia. Interviews were conducted with team members and diagnostic examinations were observed. We illustrate that clinicians use communicative body work and verbal communication to transform a material terrain into diagnostic space, and we illustrate how this diagnostic space configures forms of embodied ‘sensing‐and‐acting’ within. We argue that a ‘diagnosis’ can be conceptualised as emerging from an interaction in which space, the clinician‐body, and the patient‐body (or body‐part) mutually configure one another. By conceptualising diagnosis in this way, this article draws attention to the corporal bases of diagnostic power and counters Cartesian‐like accounts of clinical work in which the patient‐body is objectified by a disembodied medical discourse.     

比较配对诊断试验的统计方法

本文分析了以往比较配对诊断试验的方法上的错误,提出了一种比较配对诊断试验的推断方法及相应的资料形式。文中还简介了 k 系数法,并提出应用两试验的 k 系数分析来处理不完全的配对诊断试验资料的方法,结果满意。     

Validation of accuracy in image co-registration with computed tomography and magnetic resonance imaging in Gamma Knife radiosurgery

The latest version of Leksell GammaPlan (LGP) is equipped with Digital Imaging and Communication in Medicine (DICOM) image-processing functions including image co-registration. Diagnostic magnetic resonance imaging (MRI) taken prior to Gamma Knife treatment is available for virtual treatment pre-planning. On the treatment day, actual dose planning is completed on stereotactic MRI or computed tomography (CT) (with a frame) after co-registration with the diagnostic MRI and in association with the virtual dose distributions. This study assesses the accuracy of image co-registration in a phantom study and evaluates its usefulness in clinical cases. Images of three kinds of phantoms and 11 patients are evaluated. In the phantom study, co-registration errors of the 3D coordinates were measured in overall stereotactic space and compared between stereotactic CT and diagnostic CT, stereotactic MRI and diagnostic MRI, stereotactic CT and diagnostic MRI, and stereotactic MRI and diagnostic MRI co-registered with stereotactic CT. In the clinical study, target contours were compared between stereotactic MRI and diagnostic MRI co-registered with stereotactic CT. The mean errors of coordinates between images were < 1 mm in all measurement areas in both the phantom and clinical patient studies. The co-registration function implemented in LGP has sufficient geometrical accuracy to assure appropriate dose planning in clinical use.     

Body dissatisfaction in bulimia nervosa: Relationship to weight and shape concerns and psychological functioning

The evolution of diagnostic criteria from DSM-III to DSM-Ill-R for bulimia nervosa included the addition of overconcern with body shape and weight as a psychological dimension. This survey of 524 bulimic females in Toronto and New York documents the prevalence of the more specific dimension of body dissatisfaction in this population and highlights its association with related psychological disturbances. The virtual ubiquity of this dimension is discussed in terms of implications for future diagnostic criteria.     

The (in)validity of sensitivity and specificity

This paper is a legacy of the first author, and after her untimely death reconstructed by the second author as a tribute to Irene Guggenmoos's contribution to biostatistics. It discusses two different views on diagnostic testing: the classical view in which sensitivity and specificity of a diagnostic test are considered universal constants, and the more statistical point of view that focuses on predictive values. The differences between the two paradigms are outlined and practical examples are discussed to show that the familiar concepts of sensitivity and specificity must be handled with care and not used indiscriminately.     

Meta-Analysis of the Accuracy of Two Diagnostic Tests Used in Combination: Application to the Ddimer Test and the Wells Score for the Diagnosis of Deep Vein Thrombosis

ObjectivesIt is standard practice for diagnostic tests to be evaluated against gold standards in isolation. In routine clinical practice, however, it is commonplace for multiple tests to be used before making definitive diagnoses. This article describes a meta-analytic modeling framework developed to estimate the accuracy of the combination of two diagnostic tests, accounting for the likely nonindependence of the tests.MethodsA novel multicomponent framework was developed to synthesize information available on different parameters in the model. This allows data to be included from studies evaluating single tests or both tests. Different likelihoods were specified for the different sources of data and linked by means of common parameters. The framework was applied to evaluate the diagnostic accuracy of the Ddimer test and the Wells score for deep vein thrombosis, and the results were compared with those of a model in which independence of tests was assumed. All models were evaluated by using Bayesian Markov chain Monte Carlo simulation methods.ResultsThe results showed the importance of allowing for the (likely) nonindependence of tests in the meta-analysis model when evaluating a combination of diagnostic tests. The analysis also highlighted the relatively limited impact of those studies that evaluated only one of the two tests of interest.ConclusionsThe models developed allowed the assumption of independence between diagnostic tests to be relaxed while combining a broad array of relevant information from disparate studies. The framework also raises questions regarding the utility of studies limited to the evaluation of single diagnostic tests.     

Time to diagnosis and treatment of breast cancer: results from the National Breast and Cervical Cancer Early Detection Program, 1991-1995

OBJECTIVES: This study examined times to diagnosis and treatment for medically underserved women screened for breast cancer. METHODS: Intervals from first positive screening test to diagnosis to initiation of treatment were determined for 1659 women 40 years and older diagnosed with breast cancer. RESULTS: Women with abnormal mammograms had shorter diagnostic intervals than women with abnormal clinical breast examinations and normal mammograms. Women with self-reported breast symptoms had shorter diagnostic intervals than asymptomatic women. Diagnostic intervals were less than 60 days in 78% of cases. Treatment intervals were generally 2 weeks or less. CONCLUSIONS: Most women diagnosed with breast cancer were followed up in a timely manner after screening. Further investigation is needed to identify and then address factors associated with longer diagnostic and treatment intervals to maximize the benefits of early detection.     

Cardiac examination and the effect of dual-processing instruction in a cardiopulmonary simulator

Use of dual-processing has been widely touted as a strategy to reduce diagnostic error in clinical medicine. However, this strategy has not been tested among medical trainees with complex diagnostic problems. We sought to determine whether dual-processing instruction could reduce diagnostic error across a spectrum of experience with trainees undertaking cardiac physical exam. Three experiments were conducted using a similar design to teach cardiac physical exam using a cardiopulmonary simulator. One experiment was conducted in each of three groups: experienced, intermediate and novice trainees. In all three experiments, participants were randomized to receive undirected or dual-processing verbal instruction during teaching, practice and testing phases. When tested, dual-processing instruction did not change the probability assigned to the correct diagnosis in any of the three experiments. Among intermediates, there was an apparent interaction between the diagnosis tested and the effect of dual-processing instruction. Among relative novices, dual processing instruction may have dampened the harmful effect of a bias away from the correct diagnosis. Further work is needed to define the role of dual-processing instruction to reduce cognitive error. This study suggests that it cannot be blindly applied to complex diagnostic problems such as cardiac physical exam.     

Reliable and sample saving gene expression analysis approach for diagnostic tool development

This work answers the question of whether it is necessary to hybridize individual instead of pooled RNA samples on microarrays for screening gene targets suitable as diagnostic tools for radiation exposure scenarios, while at the same time meeting comparable microarray quality criteria. For developing new clinical diagnostic tools, a two-stage study design was employed in five projects. At first, pooled and not individual RNA samples were hybridized on microarrays for screening purposes. Potential gene candidates were selected based on their fold-change only. This was followed by a validation/quantification step using individual RNA samples and quantitative RT-PCR. Quality criteria from the screening approach with pooled RNA samples were compared with published data from the MicroArray Quality Control (MAQC) consortium that hybridized each reference RNA sample separately and established quality criteria for microarrays. When comparing both approaches, only insignificant differences for quality criteria such as false positives, sensitivity, specificity, and overall agreement were found. However, material, costs, and time were drastically reduced when hybridizing pooled RNA and gene targets applicable for clinical diagnostic purposes could be successfully selected. In search of new diagnostic tools for radiation exposure scenarios, the two stage study design using either pooled or individual RNA samples on microarrays shows comparable quality criteria, but the RNA pooling approach saves unique material, costs, and efforts and successfully selects gene targets that can be used for the desired diagnostic purposes.     

The assessment of a new technology for evaluating respiratory abnormalities in sleep.

This study assessed the diagnostic utility of two technologies for evaluating respiratory abnormalities in sleep. We compared conventional polysomnography with a new, ambulatory microprocessor technology. Two key features of the comparison involved: (a) the use of multiple, skilled interpreters of each system; and (b) inter-rater agreement within the systems as a crucial test for the diagnostic utility of each. Results indicated that general categories of respiratory abnormalities could be judged more reliably than more specific categories, regardless of technology. For certain categories of respiratory abnormalities, however, inter-rater agreement with the newer technology was extremely low (e.g., reliability coefficients of .12, .09, and -0.6). Factors contributing to these low diagnostic reliabilities are discussed. Our data indicate that any assessment of new technology cannot be made apart from the clinical judgments to be rendered with that new technology. This approach may be generalizable to the assessment of other diagnostic technologies.     

多功能牙病诊断仪的研制与应用

本文介绍了由微机控制的多功能牙病诊断仪的功能及临床应用。     

胆道系统影像学诊断的现状

随着科学技术发展和先进仪器的使用,胆道疾病影像学检查方法日益增多,在临床工作中如何选择最佳检查方法是临床医师面临的一个难题,为此,本文就胆道系统影像学诊断的现状加以综述。     

临床常用疾病诊断编码库的构建与思考

按照医疗机构信息系统疾病诊断编码库建设及临床医生、编码员的任务分配情况，将编码技术分为4种模式。重点介绍临床常用疾病诊断编码库的建设、维护经验与应用效果。认为临床常用疾病诊断编码库建设对于提高编码效率和质量具有重要意义，建议国家尽快制定标准的临床疾病诊断术语集，建立高素质的专业化疾病编码人才队伍，借助信息技术实现疾病诊断编码自动化与智能化。     

Staging of non-small-cell lung cancer and application of FDG-PET. A cost modeling approach

BACKGROUND: The presence of (distant) metastases affects the therapy (operation) and prognosis of patients with non-small-cell lung cancer (NSCLC). Fifty percent of the operations are futile due to the presence of a locally advanced tumor or distant metastases. Therefore, more accurate preoperative staging is required with respect to the outcomes (reduction of futile operations) and costs. This study examines current staging procedures and assesses possible situations for incorporating positron emission tomography (PET). METHODS: A retrospective analysis was performed to assess actual clinical practice in the staging procedure of 337 patients with NSCLC in two Dutch hospitals. Consequently, by combining these data of actual clinical practice with a literature review, a model was developed to determine the influence of PET on the staging outcomes and the costs. In this model the accuracy and costs of PET can be varied as well as the extent of substitution of conventional diagnostic tests by PET. RESULTS: Practice variation was found between the two hospitals with regard to the setting in which the diagnostic staging took place (hospitalization, outpatient setting) and the extent of the use of mediastinoscopy. This was reflected in the costs and in the number of (futile) operations. CONCLUSION: Hospitalization is the major cost driver in these patients. From a cost viewpoint, the evaluation of PET in a strategy after diagnostic imaging but prior to invasive staging seems most optimal.     

Development and Clinical Evaluation of a CRISPR-Based Diagnostic for Rapid Group B Streptococcus Screening

Vertical transmission of group B Streptococcus (GBS) is among the leading causes of neonatal illness and death. Colonization with GBS usually is screened weeks before delivery during pregnancy, on the basis of which preventive measures, such as antibiotic prophylaxis, were taken. However, the accuracy of such an antenatal screening strategy has been questionable because of the intermittent nature of GBS carriage. We developed a simple-to-use, rapid, CRISPR-based assay for GBS detection. We conducted studies in a prospective cohort of 412 pregnant women and a retrospective validation cohort to evaluate its diagnostic performance. We demonstrated that CRISPR-GBS is highly sensitive and offered shorter turnaround times and lower instrument demands than PCR-based assays. This novel GBS test exhibited an overall improved diagnostic performance over culture and PCR-based assays and represents a novel diagnostic for potential rapid, point-of-care GBS screening.     

On the specificity of healing functions: a study of diagnosis in three faith healing institutions in Feira (Bahia, Brazil)

This essay examines three popular ethnomedical institutions in Brazil: faith healers, Protestant evangelicals, and the practitioners of one of the Japanese new religions. In particular, I compare the relative degrees of diagnostic specificity in their practices. Medical anthropologists have neglected the analysis of this aspect of practice, although I show in the present paper its utility for comparative work. Also, I show that diagnostic specificity is congruent with an ontological view of illness and an active role for the healer, while lack of diagnostic specificity is congruent with a very general form of therapy, such as is found in the Seicho-no-Ie religion. Traditional rezadores, in contrast, use a high degree of diagnostic specificity.