AbstractBackgroundThe extent to which existing legacy memory tests are accurate and sensitive in detecting early cognitive decline is questionable. This reflects the wider picture in neurodegenerative conditions where clinical rating scales have not been developed for early‐stage disease. Item banks delivered through computer adaptive tests can help. But, in order to be fit‐for‐purpose, this approach requires a metrological framework with recourse to units, traceability, and interoperability. Here we describe the initial research to build such an item bank, based on legacy tests.MethodMemory tests (i.e., Corsi Block Test [CBT], Digit Span Test [DST], Rey’s Auditory Verbal Learning Test [RAVLT] and Word Learning List [WLL]) data were collected in the European EMPIR NeuroMET and the SMART cohorts recruited in Charité Hospital (Healthy control n 86; Subjective Cognitive Decline n 99; Mild Cognitive Impairment n 37; and Alzheimer’s Disease n 45). In order to align with metrological requirements, Rasch measurement theory in conjunction with construct specification equations were chosen to analyse the data.ResultBased on the combined dataset, when analyzed on their own, the data from the CBT, DST, RAVLT and WLL revealed skewness, gaps, and large measurement uncertainties. The addition of items from each of the tests into a bank improved these psychometric issues, improving reliability from a minimum of 0.65 to 0.85. The metrological legitimization of the ‘NeuroMET Memory Metric’ (formed from the combination of items) was confirmed through construct specification equations, which provided a Pearson correlation coefficient for empirical values vs. predicted (zR) values of up to 0.98 for task difficulty.ConclusionOur early promising findings provide a strong foundation for a metric of memory ability, which can be used as the basis for computer adaptive testing, better targeted measurement, and more accurate discrimination of early cognitive decline. Establishing units can also provide for the potential of developing crosswalks between a wider range of memory test items. Further work includes further longitudinal data collection to confirm item estimates, development of a digital platform, and a quality assurance program to establish traceability, and interoperability.