Developing a controlled vocabulary for use in a hospital information system.

In bringing a controlled vocabulary to a health information system, it is important to include those terms commonly used by those who must routinely input data to the system. We have developed a methodology whereby we can obtain "free text" descriptions of diagnoses entered by system users. We then sort those terms/concepts by system and find the appropriate "atomic" term(s). The terms are also being submitted to domain experts for appropriateness and fidelity. These concepts are then coded in an international coding system (SNOMED International) to eventually be entered into the controlled "pick list" of terms available for users to enter.