A method for sending buffer status information includes checking if a quality of service (QoS) parameter is defined for a first logical channel and at least one condition of the set of predetermined conditions associated with a logical channel group is fulfilled. If the QoS parameter is defined and at least one condition of the set is fulfilled, the method includes setting a number of bits in a media access control header according to a first semantic. The bits carry buffer status information, and the first semantic—is based on the QoS parameter of the first logical channel. Otherwise, the method includes setting the number of bits carrying the buffer status information according to a second semantic that is based on an amount of data available for transmission across the logical channel group.