1. A method, comprising: collecting, by a core network element, a plurality of anonymous radio failure reports, wherein each radio failure report comprises a cell radio network temporary identifier of a corresponding user equipment and a timestamp corresponding to a time when a reported event of the radio failure report occurred; collecting a plurality of private data reports, each comprising a cell radio network temporary identifier of a corresponding user equipment, wherein first trace jobs for collecting the plurality of private data reports are separate from second trace jobs for collecting the radio failure reports, making the radio failure reports and private data reports separate and initially unassociated upon reception; and determining which radio failure report and private data report from the plurality of radio failure reports and private data reports are from a same user equipment based on the received cell radio network temporary identifiers and the timestamps; wherein the cell radio network temporary identifier is a last cell radio network temporary identifier before the time when the reported event of the radio failure report occurred.