The invention relates to a message for reporting a channel quality of a communication system, a corresponding method and apparatuses performing such method. The invention is inter alia applicable to a 3GPP LTE and LTE-A system as standardized by the 3rd Generation Partnership Project (3GPP). The invention provides a structure (message) that allows conveying channel quality information in a manner allowing an unambiguous identification of the size channel quality information. This is achieved by defining a message comprising a first channel quality field consisting of a known number of bits, and a second channel quality field consisting of a variable number of bits. The number of bits and structure (of the content of the bits) of the second channel quality field is indicated by the content of the bits of the first channel quality field.