Cognitive testing for dementia is adversely affected by administration in a foreign location.

Background: It is colloquially considered that cognitive tests can be adversely affected by administration in a foreign location. However, a definitive demonstration of this is lacking in the literature. To determine whether or not this is the case, we compared the results of cognitive testing in a familiar versus foreign environment by single test administrator of individuals diagnosed with Alzheimer's disease randomized to placebo in a multi-site clinical study.

Findings: Cognitive tests were administered to 6 long-term residents of an assisted living facility at their residence (the "Familiar" cohort). The identical tests were administered to a newly admitted resident and to 2 community-dwelling individuals who drove to the administrator's office for the first time (the "Foreign" cohort). Secondary testing was administered 3 months later at the same respective locations. Caregivers of participants completed reports of mood, behavior and activities of daily living. The Familiar cohort performed equally well at both visits. The Foreign cohort performed significantly worse than the Familiar cohort at baseline. They improved statistically, and matched Familiar cohort performance, by their second visit. Caregiver reports for both cohorts were unchanged between visits.

Conclusions: These findings support the notion that a foreign location can adversely affect performance on cognitive tests, and therefore support cognitive testing in a familiar location.