A method of controlling link adaptation in a packet radio system is described, the method comprising receiving (302) a CQI (channel quality indicator) report, the CQI report including the number of parallel multi-codes, the transport block size, TBS, and the modulation scheme to be used in link adaptation; and calculating an effective code rate, ECR, based on the received CQI report. The method comprises calculating (306) new estimates for the effective code rate (ECR) and the transport block size (TBS) based on a ratio of the number of multi-codes of the CQI report and the number of multi-codes that the packet radio system has available for transmission, and executing (308) link adaptation based on the new estimates for the effective code rate (ECR) and the transport block size (TBS).