The processes and procedures used to promote interrater reliability in the abstraction of data from medical records are described. Several proactive strategies that serve the purpose of leading to standard interpretations of clinical data are discussed. These include (a) establishment of priorities for the sources of information; (b) creation of orders of value for the likeliness of validity of recorded data; (c) standardization of terminology; and (d) reaffirmation of decisions, based on an evolving body of evidence. Lessons learned from this project can assist nurse researchers to develop high-quality information retrieval methods, when multiple observers (or abstractors) are used during a medical record abstraction data collection process.