In one aspect, a method to collect performance measurements a digital cellular communication network is provided. Radio links of the active set are set up both inside the serving cell and towards one or more adjacent cells belonging to adjacent clusters controlled by respective radio network controllers. Controllers are connected to one another in order to act either as master of the active set in communication with the core network or slave for managing directly controlled radio resources and executing requests from the master devoted to radio link set up or deletion. The master radio controller, when calling a slave for requesting a specific radio link deletion from the active set, also sends to it some information about the cause of that deletion. The slave radio controller when receives the cause information increments a performance measurement counter associated to the specific cause and to the specific cell the radio link deletion is requested for. Operatively, the 3GPP RNSAP Radio Link Deletion Request message is upgraded to include an Element used to specify the "Cause" of the deletion. Periodically the network operator recovers the counters to associate the specific radio link failure events to the specific cells.