Disscusion

       Under conditions that might be present in many clinical practices, the acceptance/completion rate for telephonic mental status assessment among participants 75 years and older was only 55%. Of those who underwent cognitive assessment, the yield of cognitively impaired participants was low. Only 3% scored in the range that was indicative of cognitive impairment.

      Among the interviewees, willingness to consult with a physician regarding memory problems detected during a telephonic screen was quite high (87%).

       The low number of individuals who scored in the impaired range suggests that the telephonic strategy did not serve to uncover undiagnosed cognitive impairment in this elderly cohort. We believe we should have
encountered 20 screen failures (roughly a 10% prevalence in this 75+ year only age group), in contrast to the seven we found.
       We suspect that the lower-than-expected number of cases occurred as a result of selective refusal by participants with cognitive difficulties to participate in the telephonic screening. Unfortunately, we have no way of determining the cognitive status of those individuals who refused to be interviewed. From other studies in which cognitive status was available from an earlier visit prior to a refusal to continue to participate, those who refused to participate in follow-up had lower performance at baseline. In the Canadian experience, of 147 participants whose cognitive screening was abnormal, but who refused to undergo a clinical examination, their mental status score was more than seven points lower on the Modified Mini-Mental State examination, compared with those who continued to participate in the study (81.3 vs. 88.8).
     The low overall rate of completion of interviews could be attributed to a basic flaw in the telephonic strategy. In current American culture, telephone marketing is widespread, and many people, upon receiving phone
calls from strangers, may resent the intrusion. An alternative strategy would have been for us to have engaged the primary physicians in this clinic and encouraged them to promote participation. Because patients might see their physicians only every 6 months or less, such an approach would work only if our project had had a longer time scale.
      The findings of the present study suggest to us that telephonic screening is a useful and efficient strategy to identify those who do not need face-to-face cognitive assessments. Assuming that telephonic screening
were to be identified to the health plan membership as "required" or "strongly recommended," as opposed to an optional activity tied to research as was necessarily the case with the present project, the completion rate
could be higher. The number of elders who would then need face-to-face examinations would be perhaps only a half or a third of all individuals over age 75 years.