Protocol for observational study of digital cognitive assessments in post-COVID-19 condition

This is a protocol for a single-center, cross-sectional observational study within the Luxembourgish Predi-COVID cohort. The study population includes participants aged 25-65 years with and without persistent COVID-19 symptoms. The intervention involves cognitive assessments using the VMTech device and standardized neuropsychological tests, with participants without post-COVID-19 condition (PCC) serving as the comparator.

The primary outcome is the agreement between digital and standard cognitive assessments. Secondary outcomes include sensitivity, specificity, receiver operating characteristic analyses, comparison of cognitive performance between participants with and without PCC, and associations with cognitive reserve proxies. The study is cross-sectional with no follow-up reported.

No main results are provided in the protocol, as this is an early-stage publication. Safety data are not reported; adverse events, serious adverse events, discontinuations, and tolerability are all noted as not reported.

Key limitations include the observational design, which cannot establish causation, and the lack of reported sample size for the NCT04380987 cohort. The study is a protocol, so results are not yet available. Practice relevance is not reported.

Clinicians should interpret this as a planned study; it does not provide evidence for current practice. The design is observational, and causation cannot be inferred.