The inability to efficiently screen the cognitive status of homebound elderly patients can hamper clinicians' ability to plan for safe, appropriate care. In this study, the six-item Orientation-Memory-Concentration (OMC) Test was administered to 12 elderly patients during a routine office visit. That same afternoon, each participant was called at home and the OMC repeated by telephone. Test-retest correlation was excellent (Pearson's correlation =.992). Concurrent validity was supported by complete (100%) agreement between the clinicians' subjective impressions of the patients' mental status and OMC ratings. The outcome implies that telephone screening of cognitive status can be reliable.