Representation of practice guidelines with XML--modeling with XML schema.

OBJECTIVES: Data and information in medicine are mainly represented in slightly structured or even unstructured, narrative text documents. It is nearly impossible to detect and handle relationships between data elements within narrative documents or to retrieve parts of documents that contain specific information. But information access and retrieval are essential to serve the delivery and application of evidence-based medicine. METHODS: The eXtensible Markup Language (XML) provides a standard means to explicitly describe a document's structure and to identify meaningful elements inside textual narrations. Information about the state-of-the-art medical care can be delivered to the physician by different means and media. Clinical practice guidelines are thought to be one possible solution to summarize and present current medical evidence. RESULTS: The structuring of resources containing medical information with XML can facilitate the provision of problem-specific medical information at the point of care by improving content retrieval and presentation. In our project, the XML Schema is used for the electronic representation in order to structure guidelines (and other text-based resources) in a standardized way. CONCLUSION: The transition from unstructured textual data towards structured and coded data will be a migration process. One of the premises of our approach is that the structure that is defined by the information model doesn't restrict the content of the documents. This approach may fill the gap between computerized, algorithmic guideline recommendations and text-based guideline distributions.

Towards case-based performance measures: uncovering deficiencies in applied medical care.

Measures are designed to evaluate the processes and outcomes of care associated with the delivery of clinical (and non-clinical) services. They allow for intra- and interorganizational comparison to be used continuously to improve patient health outcomes. The use of performance measures always means to abstract the complex reality (medical scenarios and procedures) in order to provide an understandable and comparable output. Measures can focus on global performance. The more detailed data are available the more specific judgements with respect to the appropriateness of clinical decision-making and implementation of evidence are feasible. Externally reported measures are intended both to inform and lead to action. By providing this information, deficiencies in patient care and unnecessary variations in the care process can be uncovered. Such variations have contributed to disparities in morbidity and mortality. The developments in information technology, especially world-wide interconnectivity, standards for electronic data exchange and facilities to store and manage large amounts of data, offer the opportunity to analyse health-relevant information in order to make the delivery of healthcare services more transparent for consumers and providers. Global performance measures, such as the overall life expectancy (mortality) in a country, can give a rough orientation of how well health systems perform but they do not offer general solutions nor specific insights into care processes that have to be improved. In contrast to population-based measures, case-based performance measures use a defined group of patients depending on specific patient characteristics and features of disease. By means of these measures we are able to compare the number of patients that receive a necessary medical procedure against those patients who do not. The use of case-based measures is a bottom-up approach to improve the overall performance in the long run. They are not only a tool for global orientation but can offer a straightforward link to the areas of deficient care and the underlying procedures. Performance measures are relevant to providers as well as consumers, from their own individual perspective. Cased-based measures focus on the management of individual patient. This approach to performance measurement can inform physicians in a meaningful and constructive way by monitoring their individual performance and by pointing out possible areas of improvement.

Value of XML in the implementation of clinical practice guidelines--the issue of content retrieval and presentation.

The purpose of guidelines in clinical practice is to improve the effectiveness and efficiency of clinical care. It is known that nationally or internationally produced guidelines which, in particular, do not involve medical processes at the time of consultation, do not take local factors into account, and have no consistent implementation strategy, have limited impact in changing either the behaviour of physicians, or patterns of care. The literature provides evidence for the effectiveness of computerization of CPGs for increasing compliance and improving patient outcomes. Probably the most effective concepts are knowledge-based functions for decision support or monitoring that are integrated in clinical information systems. This approach is mostly restricted by the effort required for development and maintenance of the information systems and the limited number of implemented medical rules. Most of the guidelines are text-based, and are primarily published in medical journals and posted on the internet. However, internet-published guidelines have little impact on the behaviour of physicians. It can be difficult and time-consuming to browse the internet to find (a) the correct guidelines to an existing diagnosis and (b) and adequate recommendation for a specific clinical problem. Our objective is to provide a web-based guideline service that takes as input clinical data on a particular patient and returns as output a customizable set of recommendations regarding diagnosis and treatment. Information in healthcare is to a very large extent transmitted and stored as unstructured or slightly structured text such as discharge letters, reports, forms, etc. The same applies for facilities containing medical information resources for clinical purposes and research such as text books, articles, guidelines, etc. Physicians are used to obtaining information from text-based sources. Since most guidelines are text-based, it would be practical to use a document-based solution that preserves the original cohesiveness. The lack of structure limits the automatic identification and extraction of the information contained in these resources. For this reason, we have chosen a document-based approach using eXtensible Markup Language (XML) with its schema definition and related technologies. XML empowers the applications for in-context searching. In addition it allows the same content to be represented in different ways. Our XML reference clinical data model for guidelines has been realized with the XML schema definition. The schema is used for structuring new text-based guidelines and updating existing documents. It is also used to establish search strategies on the document base. We hypothesize that enabling the physicians to query the available CPGs easily, and to get access to selected and specific information at the point of care will foster increased use. Based on current evidence we are confident that it will have substantial impact on the care provided, and will improve health outcomes.

Evaluating the implications of clinical practice guidelines for patient care.

Patient care evaluation studies have been developed by the Commission on Cancer of the American College of Surgeons. The studies were primarily designed to monitor trends in diagnosis, therapy, and outcome of specific oncologic diseases in hospitals and cancer centers. As they reflect the current standards of patient care, patient care evaluation studies have become valid tools of quality management in medicine. In an international pilot project that began in 1996, this approach was redefined to evaluate the impact of current clinical practice guidelines in oncology. Close cooperation between medical societies in the United States and Germany under the coordination of the Commission on Cancer and the Institute of Medical Informatics at the Justus-Liebig-University of Giessen was established. This infrastructure for data collection, data management, analysis, and interpretation of results allows for the recognition of international differences in patient care. Our results indicate discrepancies between current state-of-the-art patient care represented by clinical practice guidelines and the diagnostic and therapeutic procedures in the clinical routine. Patient care evaluation studies are designed as exploratory, not confirmatory, trials. In contrast with confirmatory trials, their aims may not always lead to predefined hypotheses. They reflect routine practice and are not the basis of the formal proof of efficacy, although they may contribute to the total body of relevant evidence. Without this comprehensive approach to evaluation, the potential of clinical practice guidelines to improve patient care remains unknown.

DTDs go XML schema--a tools perspective.

Document Type Definitions (DTDs) are widely used to describe the structure of XML documents. The Clinical Document Architecture (CDA) and the Guideline Element Model (GEM) are examples from the healthcare domain. XML schemas provide another way to describe types of XML documents. In this paper we aim to advocate XML schemas from the perspective of an ANSI standard, the XML based CDA from HL7 (ANSI/HL7 CDA R1.0-2000). It turned out that existing tools do not fully exploit the knowledge contained in DTDs and XML schemas. The result of this study is a set of tools (DTD to XML Schema translator, DTD and XML schema browser, XML editor), which can be downloaded from the official W3C site and which work with any DTD and XML schema.

Presentation of problem-specific, text-based medical knowledge: XML and related technologies.

Systematic reviews of the impact of clinical decision support systems on provider behavior and patient outcome have shown evidence of benefit. Knowledge-based functions for decision support or monitoring that are integrated in clinical information systems are a potentially effective way. But these concepts are restricted by the efforts required for development and maintenance of the information systems and the limited number of implemented medical rules. Physicians are familiar to get their information from text-based sources. It seems to be straight-forward to rely on a document-based solution in order to present problem-specific information at the point of care. We have developed a concept for context-sensitive retrieving and presentation of text-based medical knowledge (textbook of internal medicine) using the eXtensible Markup Language (XML) and related technologies. This concept can facilitate the electronic query and presentation of this resource. XML may replace narrative text as a storage format and allows to structure the data in a stepwise fashion. On the basis of structured data we are able to improve the search quality for clinical information and its presentation which forms a crucial pre-requisite for the use of the information and the implementation of evidence-based care in the clinical routine.

Current practice of radioiodine treatment in the management of differentiated thyroid cancer in Germany.

This prospective, observational study of a cohort of thyroid cancer patients in Germany focusses on the "real-world" practice in the management of thyroid cancer patients. This report includes data from 2376 patients with primary differentiated thyroid carcinoma first diagnosed in the year 1996. The study reveals considerable differences in actual practice concerning surgery and radioiodine treatment. The results indicate that consensus is lacking with respect to the multimodality treatment approach for differentiated thyroid carcinoma. Our analysis represents the most current and comprehensive national assessment of presenting patient characteristics, diagnostic tests, treatment and complications for thyroid cancer.

Confronting actual practice with practice guidelines in oncology.

Improving health care quality requires the availability of data to identify and eliminate unnecessary variations in the care process. Variations can be caused by an ineffective implementation of research findings or by obstacles to the translation of research into clinical practice. The analysis of current patterns of care by the use of routine data from electronic patient records or clinical registries may help highlight these deficiencies in actual care. The growing infrastructure of information technologies and the knowledge about clinically relevant variations of routine practice may help us understand the mechanisms that are impeding the translation of research into practice. There is a need to scrutinize these variations of practice and the barriers to guideline implementation. We think that an understanding and open discussion of such reasons may help, to continuously improve the quality of patient care. This process facilitates efforts and strategies to implement evidence-based medicine in the daily routine.