Referencing familial and social relationships between patients supplies val
uable information for thr retrieval and interpretation of clinical data. We
present a technique for the incorporation of patient relations into data r
etrieval that takes into account the specific properties of routinely colle
cted clinical data. In most clinical databases, family relations are docume
nted in a fragmentary manner at best. Furthermore, clinical retrieval syste
ms do not support inter-patient queries in most cases. Our model is designe
d to formulate direct relations between patients and to identify patients a
s members of either temporary or persistent communities. In this way, the m
odel supplies information on both genetic and social relations.