Monday, November 19, 2012

Materials and Methods

       The interview was designed to require no more than 5 minutes to administer and to be standardized so that a person with no clinical training could conduct the interview over the phone. The interview contains one item testing for the delayed recall of a list of three objects. The interview also contains some simple questions about cognitively demanding activities of daily living. Initially, the interview was given to a group of AD patients and agematched controls to determine its acceptability and whether there were obvious problems with telephonic administration and scoring.

      This pilot evaluation lead to rewording of some items and to clarifications in the administration procedure. We are now conducting a reliability and concurrent validity study. There are 90 participants in this study, all of whom have received a cognitive and diagnostic evaluation by a team of dementia experts in the past 6 months. Some of the participants have AD and others are elderly, nondemented controls.

      The telephone interviewers are blind to the participant's diagnosis and cognitive evaluation data. To assess reliability, each participant is being interviewed twice during a 1-month period. Concurrent validity will be assessed by determining the correspondence between scores on the screening interview and the participant's most recent clinical diagnosis.

      More detailed analyses will look at the ability of the screening instrument to identify AD patients with very mild disease. Although the sample size is too small to draw definitive conclusions about the possible influence of confounding variables, we will also examine the relationship of screening test scores to factors such as education, age, and medical comorbidities. These analyses will determine the reliability of the screening tool and provide a first look at its ability to identify cases of AD. Further validity studies will be conducted, subsequently, provided that the reliability and validity data in the current study are acceptable. One additional study will involve elderly patients enrolled in a managed care plan. None of the participants in this study will have received a full diagnostic evaluation for dementia. Participants will be screened over the telephone and determined to be cognitively normal or possibly impaired. Subsets from each group will then be examined clinically to determine the extent to which the scr

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