An intermittent urinary catheterisation assembly comprising: - an intermittent urinary catheter comprising: ∘ a catheter tube comprising an insertable portion intended for insertion into a user's urethra, a non-insertable portion not intended for insertion into the user's urethra, and a connecting portion being integral with or mounted to the non-insertable portion; and o a conduit extending longitudinally within the tube and defining at least part of a flow path from a distal insertion end of the catheter to a proximal outlet end thereof; - a measuring system configured to measure at least a pressure in the conduit and/or in a space in communication with the conduit, wherein the measuring system comprises: ∘ a signal processing device comprising a housing with an engagement mechanism for detachably securing the signal processing device in relation to the connecting portion of the catheter; ∘ at least one valve element in fluid communication with the conduit when the signal processing device is secured in relation to the intermittent urinary catheter, the at least one valve element comprising a cut-off element configured to switch from a closed state disabling liquid flow in the conduit to an open state enabling liquid flow in the conduit in response to a pressure applied to the cut-off element by liquid in the conduit; and ∘ at least one sensor element configured to measure a parameter indicative of the pressure applied to the cut-off element when the cut-off element switches from the closed state to the open state, wherein the measuring system is configured to detect a change of state of the cut-off element from the closed state to the open state. - an intermittent urinary catheter comprising: ∘ a catheter tube comprising an insertable portion intended for insertion into a user's urethra, a non-insertable portion not intended for insertion into the user's urethra, and a connecting portion being integral with or mounted to the non-insertable portion; and o a conduit extending longitudinally within the tube and defining at least part of a flow path from a distal insertion end of the catheter to a proximal outlet end thereof; ∘ a catheter tube comprising an insertable portion intended for insertion into a user's urethra, a non-insertable portion not intended for insertion into the user's urethra, and a connecting portion being integral with or mounted to the non-insertable portion; and o a conduit extending longitudinally within the tube and defining at least part of a flow path from a distal insertion end of the catheter to a proximal outlet end thereof; - a measuring system configured to measure at least a pressure in the conduit and/or in a space in communication with the conduit, wherein the measuring system comprises: ∘ a signal processing device comprising a housing with an engagement mechanism for detachably securing the signal processing device in relation to the connecting portion of the catheter; ∘ at least one valve element in fluid communication with the conduit when the signal processing device is secured in relation to the intermittent urinary catheter, the at least one valve element comprising a cut-off element configured to switch from a closed state disabling liquid flow in the conduit to an open state enabling liquid flow in the conduit in response to a pressure applied to the cut-off element by liquid in the conduit; and ∘ at least one sensor element configured to measure a parameter indicative of the pressure applied to the cut-off element when the cut-off element switches from the closed state to the open state, ∘ a signal processing device comprising a housing with an engagement mechanism for detachably securing the signal processing device in relation to the connecting portion of the catheter; ∘ at least one valve element in fluid communication with the conduit when the signal processing device is secured in relation to the intermittent urinary catheter, the at least one valve element comprising a cut-off element configured to switch from a closed state disabling liquid flow in the conduit to an open state enabling liquid flow in the conduit in response to a pressure applied to the cut-off element by liquid in the conduit; and ∘ at least one sensor element configured to measure a parameter indicative of the pressure applied to the cut-off element when the cut-off element switches from the closed state to the open state,