Report Number: CS-TR-96-1565
Institution: Stanford University, Department of Computer Science
Title: A Formal Model for Bridging Heterogeneous Relational
Databases in Clinical Medicine
Author: Sujansky, Walter
Date: April 1996
Abstract: This document describes the results of my thesis research,
which focused on developing a standard query interface to
heterogenous clinical databases. The high-level goal of this
work was to *insulate* the developers of clinical computer
applications from the implementation details of clinical
databases, thereby facilitating the *sharing* of clinical
computer applications across institutions with different
database implementations.
Most clinical databases store information about patients'
diagnoses, laboratory results, medication orders, drug
allergies, and demographic background. These data are
valuable as the inputs to computer applications that provide
real-time decision support, monitor the quality of care, and
analyze data for research purposes. Clinical databases at
different institutions, however, vary significantly in the
way the databases model, represent, and retrieve clinical
data. This database heterogeneity makes it impossible for a
single computer application to retrieve data from the
clinical databases of various institutions because the
database queries included in the application must be
formulated differently for each institution. Therefore,
database heterogeneity makes it difficult to share computer
applications across institutions with different database
implementations.
In my work, I have developed an *abstract* model of clinical
data and an *abstract* query language that allow the
developers of computer applications to formulate queries
independently of the institution-specific features of
clinical databases. I have also developed a database mapping
language and a formal query-translation method that
automatically translate the abstract queries that appear in
applications into equivalent institution-specific queries.
This framework ostensibly allows copies of a single computer
application to be distributed to multiple institutions and to
be customized automatically at each of the institutions such
that the queries in each copy of the application can retrieve
data from the local clinical database.
This dissertation formally describes the abstract data model,
the abstract query language, the mapping language, and the
translation algorithm. It also presents the results of a
formal evaluation that I performed to assess the feasibility
and utility of this approach for sharing clinical computer
applications.
http://i.stanford.edu/pub/cstr/reports/cs/tr/96/1565/CS-TR-96-1565.pdf