A method for controlling the transmission of data in a radio communications system transmits response signals from a receiver which includes information that reflects received signal quality, as well as information indicating whether an error has occurred in the data transmission. In one case, acknowledgment signals or negative acknowledgment signals may be regarded as no reply and not forwarded to a transmitter. In another case, the signals could be recognized as an acknowledgment or retransmission request by a receiver. Preferably, the signals transmitted from the receiver to the transmitter are composed of more than 2-bit multiplexed information. By transmitting response signals of this type, the transmission efficiency of packet data may be increased, and the automatic repeat request (ARQ) performance by the system may be greatly improved.