Systematic review on the process of translation and cross-cultural adaptation of functional activity tests for dementia; and, A preliminary validation of the details of function of everyday life scale for the detection of early-stage Alzheimer’s disease

Abstract

BACKGROUND: Dementia is a significant cause of disability, and the prevalence of this condition is increasing worldwide. Evaluation of functional abilities is required to ascertain the presence of dementia(s), such as Alzheimer’s disease (AD), where a decline in function is a key indicator of the disease. Accurately identifying and monitoring functional changes indicative of dementia in the early stages is crucial for ensuring timely care and support.

AIMS: The thesis is divided into two parts. The first is a systematic review and descriptive synthesis of the quality of cross-cultural adaptation and the psychometric properties of functional activity measures for use in dementia across different languages and cultures. The second is an empirical study examining whether memory binding can be integrated into a measure of functional activity, the Details of Function of Everyday Life (DoFEL) scale. This is to better understand the cognitive aspects contributing to functional decline in prodromal AD stages.

METHOD: The systematic review examined fifteen adapted functional activity measures from five databases. The second is an empirical study examining the structural, content, and construct validity of the novel DoFEL scale.

RESULTS: The systematic review revealed that fewer than half of the adapted functional activity measures identified fully adhered to established guidelines for cross-cultural adaptation or underwent a comprehensive evaluation of psychometric properties, as recommended by the Consensus-Based Standards for the Selection of Health Measurement Instruments. Findings from the empirical study highlighted that a revised version of the DoFEL scale correlated with cognitive performance on measures known to be sensitive to the early stages of AD. The revised DoFEL could also differentiate healthy older adults from those with mild cognitive difficulties, known to be at a greater risk of developing AD.

CONCLUSION: The systematic review highlights the importance of researchers following standardised guidelines for translating and cross-culturally adapting functional activity measures for dementia and ensuring the comprehensive evaluation of psychometric properties in cross-cultural settings. The findings from the empirical study suggest that exploring the link between memory binding and performance in funcWonal acWviWes could provide a valuable avenue for enhancing the assessment of funcWonal abiliWes in the early stages of Alzheimer's disease. These findings have implications for future research and clinical practice for those involved in dementia care.