reuse of software components
See the following -
Tolven - A Widely Adopted 'Open Source' Health IT Solution
By Peter Groen, and Roger A. Maduro | October 4, 2012
The Tolven Platform is rapidly becoming one of the more widely adopted open source solutions for healthcare information technology globally. Tolven clients in Europe, North America, and Asia are leveraging the breadth of solutions the Tolven technology provides to support their needs.