Conceptualization and measurement of getting lost behavior in persons with early dementia

Background: The primary purpose of this preliminary research was to describe the psychometric properties of a newly-developed Everyday Spatial Questionnaire for Dementia-patient version (ESQD-P) in a Chinese population. A secondary goal was to assess the relationship between executive functions and wayfinding strategy application. The ESQD-P is a measure for the phenomenon of 'getting lost behavior' (GLB) reported by early Alzheimer's disease sufferers, based on the concept of spatial problem-solving. Methods: With a cross-sectional descriptive design, the ESQD-P was validated by examining for internal consistency, construct validity, concurrent validity, and exploratory factor analyses among 116 outpatients in the memory disorder clinic of a veterans' general hospital in Taiwan. Other variables included were: global cognition, measured by the Cognitive Abilities Screening Instrument; stages of dementia, measured by the Clinical Dementia Rating Scale; and depressive symptoms, measured by the Geriatric Depression Scale-Short Form. Results: Findings indicated that the Chinese ESQD-P is a reliable instrument for measuring GLB (internal consistency α = 0.73). A five-factor solution explained 55.45% of the score variance, while the correlations between the patient and proxy versions of this instrument yielded an acceptable concurrent validity. Executive functions can predict both global and analytic wayfinding strategies. Conclusions: GLB may be explained in part by declining executive functions. Deleting the coping strategies subscale may improve psychometric properties of the ESQD-P.