PDL: a definition language for trend pattern representation and detection in medicine.

This paper proposes a pattern definition language, PDL, to effectively represent and manipulate trend patterns to support medical decision making in time-critical domains. Based on a modified version of SDL, a shape definitional language introduced by Agrawal, PDL extends the expressive power of SDL in the temporal domains. PDL also permits irregular length of elementary patterns to be matched in the query. This paper describes the syntax and the semantics of PDL, as well as illustrating how it can be applied in a time-critical medical domain.