The present disclosure relates to a network node, a network control node, a wireless device and corresponding methods for optimized broadcasting of system information messages in a wireless network. The disclosure proposes a method, performed in a wireless device, of assessing system information perception capability in a wireless network that is arranged to broadcast system information on at least two frequency carriers. The method comprises receiving (S10) broadcasted system information on the at least two frequency carriers. The method also comprises determining (S12), using the received broadcasted system information, frequency carrier identity correlated information for each of the at least two frequency carriers. The method further comprises reporting (S14) receipt of the broadcasted system information on the at least two frequency carriers, wherein the report includes the frequency carrier identity correlated information.