In RWE studies, Data Expert & Access Partners (DEAPs) need to align their data into a common structure using a CDM. This allows programmers to run the same script on diverse datasets. VAC4EU utilises the ConcePTION CDM, developed by the ConcePTION consortium, an IMI-funded project which aimed to establish practices to improve how the safety of medicines is monitored in pregnant or breastfeeding individuals. The tool was initially drafted after an analysis of several different European RWD sources, considering conventions from existing CDMs. Since, VAC4EU members have continuously updated this vital open-source tool in line with methodological advances.