Deliverable 2.1 is the outcome of the work conducted within Task 2.1 “Patient-centric cases and requirements definition”. According to the Grant Agreement, the objective of Task 2.1 is to identify possible use cases and describe high level technical and functional criteria that would be required by the ThrombUS+ innovative wearable system to detect, screen, monitor and thus prevent DVT. This is only the first step of the co-design process set under Work Package (WP) 2, which is to continue in the following tasks 2.2, 2.3 and 2.4 with the integration of specific regulatory, technical and functional requirements, thus ensuring a feasible design which appropriately addresses the clinical needs while remaining acceptable to the users. The present work is based on the collection and processing of medical information for several patients’ profiles provided by the clinical partners of the consortium (ATHENA, CSS-IRCSS, GNP, HSV, LSMU and TAU) and by specific clinicians that participated in additional targeted consultations.