Archana Tapuria

Implementation of a query interface for a generic record server

INTRODUCTION This paper presents work to define a representation for clinical research queries that can be used for the design of generic interfaces to electronic healthcare record (EHR) systems. Given the increasing prevalence of EHR systems, with the potential to accumulate life-long health records, opportunities exist to analyse and mine these for new knowledge. This potential is presently limited by many factors, one of which is the challenge of extracting information from them in order to execute a research query. METHOD There is limited pre-existing work on the generic specification of clinical queries. Sets of example queries were obtained from published studies and clinician reference groups. These were re-represented as structured logical expressions, from which a generalisable pattern (information model) was inferred. An iterative design and implementation approach was then pursued to refine the model and evaluate it. RESULTS This paper presents a set of requirements for the generic representation of clinical research queries, and an information model to represent any arbitrary such query. A middleware component was implemented as an interface to an existing system that holds 20,000 anonymised cancer EHRs in order to validate the model. This component was interfaced in turn to a query design and results presentation tool developed by the Open University, to permit end user demonstrations and feedback as part of the evaluation. CONCLUSION Although it is difficult to separate cleanly the evaluation of a theoretical model from its implementation, the empirical evaluation of the query-execution interface revealed that clinical queries of the kinds studied could all be represented and executed successfully. However, performance was a problem and this paper outlines some of the challenges faced in building generic components to handle specialised data structures on a large scale. The limitations of this work are also discussed. The work complements many years of European research and standardisation on the interoperable communication of electronic health records, by proposing a way in which one or more EHR systems might be queried in a standardised way.

An Electronic Healthcare Record Server Implemented in PostgreSQL

This paper describes the implementation of an Electronic Healthcare Record server inside a PostgreSQL relational database without dependency on any further middleware infrastructure. The five-part international standard for communicating healthcare records (ISO EN 13606) is used as the information basis for the design of the server. We describe some of the features that this standard demands that are provided by the server, and other areas where assumptions about the durability of communications or the presence of middleware lead to a poor fit. Finally, we discuss the use of the server in two real-world scenarios including a commercial application.

Patterns: a simple but expressive data modelling formalism

The creation of a clinical application requires models that describe the structure of data in a way that can be displayed, exchanged and stored. A number of approaches for this have been proposed and are in widespread use. However, these are often complex and/or have shortcomings in the breadth of data that they are able to represent. The annotations facility provided by many computer languages could be used to include information shaping the development and run-time behaviour of a clinical application. If this were comprehensive, then annotations alone would be sufficient for conceptual modelling. A model for representing such annotations is presented and some examples shown and discussed. The paper concludes that such a formalism is simple to use while developing semantic concepts but is capable of representing information from many models simultaneously. It is well suited to the needs of clinical teams seeking consensus on the structure of records.