JMIR Publications

ABSTRACT

Background:

Assessment of cognitive decline in the earliest stages of Alzheimer’s disease (AD) is important but challenging. AD is a neurodegenerative disease, characterized by gradual cognitive decline. Disease stages range from preclinical AD, in which individuals are cognitively unimpaired, to mild cognitive impairment (MCI) and dementia. Digital technologies are promising to detect early subtle cognitive changes. Although the field of digital cognitive biomarkers is rapidly evolving, a comprehensive overview on the reporting of psychometric properties (i.e., validity, reliability, responsiveness, clinical meaningfulness) is missing. Insight into the extent that these properties are evaluated is needed to identify the validation steps towards implementation.

Objective:

The objective of this scoping review was to identify the reporting on quality characteristics of smartphone- and tablet-based cognitive tools with potential for remote administration in individuals with preclinical AD or MCI. We focused both on psychometric properties and practical tool characteristics.

Methods:

This scoping review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews (PRISMA-ScR) guidelines. Four databases (Pubmed, Embase, Web of Science and PsycINFO) were systematically searched from January 1, 2008 to January 5, 2023. Studies were included that assessed measurement properties of a cognitive smartphone- or tablet-based tool with potential for remote administration in individuals with preclinical AD or MCI. Two reviewers independently screened titles and abstracts in ASReview, a screening tool that combines manual and automatic screening using an active learning algorithm. Thereafter, we manually screened full texts in the web application Rayyan. For each included study, two reviewers independently explored the reported information on practical and psychometric properties. For each psychometric property examples were provided narratively.

Results:

In total, 11,300 deduplicated studies were identified in the search. After screening, 50 studies describing 37 different digital tools were included in this review. Administration time was on average 13.8±10.1 minutes (range 1-32 minutes), and for 14/37 tools this was not described. Most tools (n=31/37) were examined in a single language. The investigated population were mainly individuals with MCI (n=34/37), and fewer tools were examined in individuals with preclinical AD (n=8/37). For almost all tools (n=36/37) construct validity was assessed by evaluation of clinical or biological associations, or relevant group differences. A small number of tools reported information on structural validity (n=3/37), test-retest reliability (n=12/37), responsiveness (n=6/37) or clinical meaningfulness. (n=0/37).

Conclusions:

Numerous smartphone- and tablet-based tools to assess cognition in early AD are currently being developed, while studies concerning their psychometric properties are limited. Often, initial validation steps have been performed, yet further validation, and careful selection of psychometrically valid outcome scores, is required to demonstrate clinical usefulness with regards to the context of use, which is essential for implementation.