Clock drawing in the screening assessment of cognitive impairment in an ambulatory care setting: a preliminary report

In an exploratory study to assess the utility of clock drawing as a screening test for cognitive impairment in medical/surgical outpatients, clock drawing and the 6-item Orientation-Memory-Concentration Test (OMCT) were administered to over 400 randomly selected ambulatory patients over the age of 55 in a busy inner-city hospital. The clock drawing test was completed by 431 patients, and 471 completed the OMCT. Clock drawing errors suggestive of moderate-to-severe cognitive impairment were found in 42.7% of patients; OMCT errors suggestive of moderate-to-severe cognitive impairment were found in 35.4% of the population tested. The clock drawing test might represent a quick-screen for cognitive impairment in an older general medical/surgical outpatient population, and might help identify patients not otherwise recognized as potentially unable to fully understand treatment recommendations.