We designed and implemented an ontological solution which makes provisions for choosing adequate devices/sensors for remote monitoring of patients who are suffering from post-stroke health complications. We argue that non-functional requirements in pervasive healthcare systems can be elicited and managed through semantics stored in ontological models and reasoning performed on them. Our contribution is twofold: (i) we enrich the elicitation and specification of non-functional requirements within the requirements engineering discipline and (ii) we address the pervasiveness of healthcare software systems through the way of choosing devices embedded in them, and through user expectations in terms of having access to pervasive services personalized to their needs.