Concurrent validity, test–retest reliability, and normative properties of the ignite app: A cognitive assessment for frontotemporal dementia.

Abstract

Objective: Digital biomarkers can provide frequent, real-time monitoring of health-related behavior and could play an important role in the assessment of cognition in frontotemporal dementia (FTD). However, the validity and reliability of digital biomarkers as measures of cognitive function must first be determined. Method: The Ignite cognitive app contains iPad-based measures of executive function, social cognition, and other domains affected in FTD. Here we describe the normative properties of the Ignite tests, evaluate associations with gold-standard neuropsychological tests, and investigate test–retest reliability through two healthy control studies. Over 2,000 cognitively normal adults aged 20–80 years were recruited to complete the Ignite app remotely. A separate cohort of 98 healthy controls completed Ignite at two timepoints (7 days apart), a pen and paper neuropsychology battery, and a User Experience Questionnaire. Results: Significant associations were found between age and performance on several Ignite measures of processing speed (r = 0.42–0.56, p < .001) and executive function (r = 0.43–0.62, p < .001). With the exception of one test (Time Tap), the Ignite tests demonstrated moderate to excellent test–retest reliability (intraclass correlation coefficients [ICC] = 0.54–0.92) and significant correlations with their pen and paper counterparts (r = 0.25–0.72, p < .05). The majority of participants (>90%) rated the app favorably, stating it was enjoyable and easy to complete unsupervised. Conclusions: These findings offer early support for the validity of the Ignite tests suggesting they measure the intended cognitive processes, capture a stable picture of performance over time, and are well accepted in healthy controls. This work supports the feasibility of administering the app remotely and its potential utility as a cognitive tool in FTD; however, validation is ongoing, and further work is required before Ignite can be used as an endpoint in clinical trials. Key Points

Question: How valid and reliable is the Ignite cognitive app in measuring key cognitive domains? Findings: Preliminary evidence suggests that the app offers a useful and consistent measure of cognitive performance, though its validation remains an ongoing process. Importance: Designed for remote use, the app allows individuals to complete assessments from home on an iPad, making it especially valuable for monitoring brain health over time, such as in clinical trials for frontotemporal dementia (FTD), a condition that impacts cognitive abilities. With its user-friendly design and positive reception from participants, Ignite shows promise as a research tool. Next Steps: Future studies will further explore its validity using updated versions of the app to ensure its effectiveness in detecting early cognitive impairments in individuals at risk of developing FTD.