Development of a population-based questionnaire to explore psychosocial determinants of screening for memory loss and Alzheimer Disease.

Abstract

Alzheimer disease research has focused on detecting the earliest signs of cognitive decline and efforts are ongoing to develop biomarkers and cognitive measures that reliably distinguish between nondemented and demented individuals. However, little is known about factors that may directly or indirectly influence screening behavior of older community-dwelling adults. We describe an iterative process for the development and formative evaluation of a questionnaire about dementia knowledge and screening behaviors in older adults to understand the psychosocial factors underlying intention to obtain dementia screening to profile individuals manifesting intention to undergo dementia screening compared to those who will not. The Behavioral Model of Health Services Use was used as a conceptual framework for a questionnaire with constructs from the Health Belief Model, Theory of Reasoned Action and Self-Efficacy. After pretesting, we used a random dialing strategy to test our questionnaire on a final sample of 1024 older Missourians. Internal consistency and construct validity were examined. Pretesting identified several potential problems that were improved with rewording. Cronbach alpha was greater than 0.6 (range 0.62 to 0.92) in all but one construct testing dementia knowledge, suggesting good to excellent internal consistency. Convergent (construct) validity was assessed using confirmatory factor analysis. All constructs but 3 demonstrated good validity. Addressing these issues will allow researchers to identify unique characteristics based on age, race, sex, socioeconomic differences and geographic location, and characterize barriers to screening programs to more effectively develop targeted community-based interventions.