Open QFT models in the context of linearised gravity provide a framework in which models for gravitationally induced decoherence can be formulated, with a matter system such as neutrinos as the system of interest and gravity as the chosen environment. These open QFT models do not take the Lindblad equation as their starting point, but derive the master equation from a given microscopic model. In contrast, phenomenological models in this context often take the Lindblad equation as their starting point and then assume a parametrisation of the dissipator that encodes the interaction of the system with the environment. After a brief introduction to open QFT models in the context of linearised gravity, the talk will focus on the relationship between microscopic and phenomenological models in applications to neutrino oscillations. This includes for instance questions such as: How much insight into the physical properties of an underlying microscopic model can be gained from a given parametrisation of the dissipator? And how are the properties of the coupling between the system and its environment in a microscopic model related to certain classes of parametrisations of the dissipator?