Abstract
COSTAR, a COmputer-STored Ambulatory Record system, was developed at the Massachusetts General Hospital Laboratory of Computer Science. It can supplement or entirely replace the paper medical record with a highly encoded record. Although a computer-stored medical record provides a unique opportunity for quality assurance activities, it requires programming skills to examine the data. We have taken the dual approach of writing pre-specified quality assurance packages and developing a high level Medical Query Language (MQL) that can be used by non-programmers. While each approach has pros and cons, we are encouraged by our results which show that a quality assurance program can be written reasonably well in MQL by individuals who have little programming experience.