Applying temporal joins to clinical databases.
(25/2276)
Clinical databases typically contain a significant amount of temporal information, information that is often crucial in medical decision-support systems. Most recent clinical information systems use the relational model when working with this information. Although these systems have reasonably well-defined semantics for temporal queries on a single relational table, many do not fully address the complex semantics of operations involving multiple temporal tables. Such operations can arise frequently in queries on clinical databases. This paper describes the issues encountered when joining a set of temporal tables, and outlines how such joins are far more complex than non-temporal ones. We describe the semantics of temporal joins in a query management system called Chronus II, a system we have developed to assist in evaluating patients for clinical trials. (+info)
Initial experiences with building a health care infrastructure based on Java and object-oriented database technology.
(26/2276)
A multi-tiered telemedicine system based on Java and object-oriented database technology has yielded a number of practical insights and experiences on their effectiveness and suitability as implementation bases for a health care infrastructure. The advantages and drawbacks to their use, as seen within the context of the telemedicine system's development, are discussed. Overall, these technologies deliver on their early promise, with a few remaining issues that are due primarily to their relative newness. (+info)
Integrating a modern knowledge-based system architecture with a legacy VA database: the ATHENA and EON projects at Stanford.
(27/2276)
We present a methodology and database mediator tool for integrating modern knowledge-based systems, such as the Stanford EON architecture for automated guideline-based decision-support, with legacy databases, such as the Veterans Health Information Systems & Technology Architecture (VISTA) systems, which are used nation-wide. Specifically, we discuss designs for database integration in ATHENA, a system for hypertension care based on EON, at the VA Palo Alto Health Care System. We describe a new database mediator that affords the EON system both physical and logical data independence from the legacy VA database. We found that to achieve our design goals, the mediator requires two separate mapping levels and must itself involve a knowledge-based component. (+info)
Getting data out of the electronic patient record: critical steps in building a data warehouse for decision support.
(28/2276)
Health care has taken advantage of computers to streamline many clinical and administrative processes. However, the potential of health care information technology as a source of data for clinical and administrative decision support has not been fully explored. This paper describes the process of developing on-line analytical processing (OLAP) capacity from data generated in an on-line transaction processing (OLTP) system (the electronic patient record). We discuss the steps used to evaluate the EPR system, retrieve the data, and create an analytical data warehouse accessible for analysis. We also summarize studies based on the data (lab re-engineering, practice variation in diagnostic decision-making and evaluation of a clinical alert). Besides producing a useful data warehouse, the process also increased understanding of organizational and cost considerations in purchasing OLAP tools. We discuss the limitations of our approach and ways in which these limitations can be addressed. (+info)
Multimedia explorer: image database, image proxy-server and search-engine.
(29/2276)
Multimedia plays a major role in medicine. Databases containing images, movies or other types of multimedia objects are increasing in number, especially on the WWW. However, no good retrieval mechanism or search engine currently exists to efficiently track down such multimedia sources in the vast of information provided by the WWW. Secondly, the tools for searching databases are usually not adapted to the properties of images. HTML pages do not allow complex searches. Therefore establishing a more comfortable retrieval involves the use of a higher programming level like JAVA. With this platform independent language it is possible to create extensions to commonly used web browsers. These applets offer a graphical user interface for high level navigation. We implemented a database using JAVA objects as the primary storage container which are then stored by a JAVA controlled ORACLE8 database. Navigation depends on a structured vocabulary enhanced by a semantic network. With this approach multimedia objects can be encapsulated within a logical module for quick data retrieval. (+info)
Extended SQL for manipulating clinical warehouse data.
(30/2276)
Health care institutions are beginning to collect large amounts of clinical data through patient care applications. Clinical data warehouses make these data available for complex analysis across patient records, benefiting administrative reporting, patient care and clinical research. Data gathered for patient care purposes are difficult to manipulate for analytic tasks; the schema presents conceptual difficulties for the analyst, and many queries perform poorly. An extension to SQL is presented that enables the analyst to designate groups of rows. These groups can then be manipulated and aggregated in various ways to solve a number of useful analytic problems. The extended SQL is concise and runs in linear time, while standard SQL requires multiple statements with polynomial performance. The extensions are extremely powerful for performing aggregations on large amounts of data, which is useful in clinical data mining applications. (+info)
Exploring three approaches for handling incomplete patient histories in a computer-based guideline for childhood immunization.
(31/2276)
A significant problem faced by immunization registries is that the dates of a patient's previous vaccinations may not be known. These incomplete histories can pose a problem when attempting to use a computer-based guideline to produce patient-specific immunization recommendations automatically. This paper describes an overall approach, together with 3 specific strategies, developed to help deal with this problem. The paper then describes our experience applying the approach to a database containing over 400,000 immunization histories. The paper also discusses a number of the issues raised in adapting a computer-based guideline to accommodate incomplete patient data of this sort. (+info)
Medical student database development: a model for record management in a multi-departmental setting.
(32/2276)
Student records flow through medical school offices at a rapid rate. Much of this data is often tracked on paper, spread across multiple departments. The Medical Student Informatics Group at the University of Utah School of Medicine identified offices and organizations documenting student information. We assessed departmental needs, identified records, and researched database software available within the private sector and academic community. Although a host of database applications exist, few publications discuss database models for storage and retrieval of student records. We developed and deployed an Internet based application to meet current requirements, and allow for future expandability. During a test period, users were polled regarding utility, security, stability, ease of use, data accuracy, and potential project expansion. Feedback demonstrated widespread approval, and considerable interest in additional feature development. This experience suggests that many medical schools would benefit from centralized database management of student records. (+info)