Semi-automated Database Design by the End-user

Design aspects of a distributed clinical trials information system

Backgound Clinical trials informatics has evolved through the development of multiple applications addressing distinct parts of the clinical trials cycle. This setting creates difficulties in the transport and sharing of data among applications that serve a common functionality.

Purpose We present an alternative approach for the design of clinical trials information systems consisting of loosely coupled components standing on a comprehensive model of the global clinical trial process.

Methods We describe how such a structure is able to support the development and implementation of complex knowledge-driven modules, such as automated database query systems, reporting systems and intelligent data-analysis tools, and how currently available internet technologies may be used to support the independent development of applications and collaboration between researchers.

Results These principles were applied to the development of a fully functional system that has been in production for eight years in a diversity of pharmaceutical and academic drug trials. Marked time savings in database set-up and statistical reporting have been documented, as well as good reliability in the selection of appropriate statistical methods to clinical trial data analysis.

Conclusions In order to meet the expected functionality and to avoid the proliferation of databases and software applications, clinical trials information systems need to be based on a generic model of clinical trials and on a distributed architecture.

A tool for the design of clinical forms supporting end-user integration

Computer-based forms are a common input medium for recording medical data by the electronic mode. Efficient documentation requires that the forms satisfy the specific needs and habits of clinical end-users in the collection of data. This can be effectively achieved by integrating the clinician in the process of designing the forms. However, most development environments used for the implementation of clinical forms are customized for computer specialists and are too technical in nature to be used by clinicians. We present a tool for the development of clinical forms, which supports the integration of end-users in the design process of the forms. The tool is customized for users from the medical domain, allowing interactive and intuitive development of forms based on the configuration of predefined components instead of programming. Clinicians may even design highly functional, complex forms autonomously without having to involve computer specialists at all. All collected data are stored on the basis of a generic data model favouring data retrieval. The described application has been successfully used at the University of Vienna and Graz medical schools since 1997 and 1999, respectively.

Metadata-driven creation of data marts from an EAV-modeled clinical research database

Generic clinical study data management systems can record data on an arbitrary number of parameters in an arbitrary number of clinical studies without requiring modification of the database schema. They achieve this by using an Entity-Attribute-Value (EAV) model for clinical data. While very flexible for creating transaction-oriented systems for data entry and browsing of individual forms, EAV-modeled data is unsuitable for direct analytical processing, which is the focus of data marts. For this purpose, such data must be extracted and restructured appropriately. This paper describes how such a process, which is non-trivial and highly error prone if performed using non-systematic approaches, can be automated by judicious use of the study metadata-the descriptions of measured parameters and their higher-level grouping. The metadata, in addition to driving the process, is exported along with the data, in order to facilitate its human interpretation.