Abstract: A handheld device, such as a personal digital assistant (“PDA”), can be used at the point-of-care to find an appropriate pair of diagnosis code and procedure code for use in writing an order for further medical procedures for a particular patient. The choice of diagnosis code and procedure code can be checked for conformance with the requirements set forth in a particular set of medical necessity policy rules. In a preferred embodiment, the codes and rules are aggregated by medical specialty so that a specialist can work with solely those codes and rules that are relevant to that particular medical specialty. This abstract is provided as a tool for those searching for patents, and not as a limitation on the scope of the claims.