  This article presents our steps to integrate complex and partly unstructured
medical data into a clinical research database with subsequent decision
support. Our main application is an integrated faceted search tool, accompanied
by the visualisation of results of automatic information extraction from
textual documents. We describe the details of our technical architecture
(open-source tools), to be replicated at other universities, research
institutes, or hospitals. Our exemplary use cases are nephrology and
mammography. The software was first developed in the nephrology domain and then
adapted to the mammography use case. We report on these case studies,
illustrating how the application can be used by a clinician and which questions
can be answered. We show that our architecture and the employed software
modules are suitable for both areas of application with a limited amount of
adaptations. For example, in nephrology we try to answer questions about the
temporal characteristics of event sequences to gain significant insight from
the data for cohort selection. We present a versatile time-line tool that
enables the user to explore relations between a multitude of diagnosis and
laboratory values.
