Since the onset of the Iraq war, some broadcasters have been simulcasting programmes on both a news Since the onset of the Iraq war, some broadcasters have been simulcasting programmes on both a news channel and another service. The BBC, for example, has been simultaneously broadcasting programmes on both News 24 and BBC One.
In cable and DTT homes, the BARB meter identifies the channel being viewed by matching the audio (audio is present even when a television set is turned down) in a panel home against a reference of audio for all BARB reported channels. The matching process allows the viewing to be correctly attributed. Simulcast broadcasts, however, cause a problem as the audio will match to more than one service. In this event, the normal BARB rule is to allocate the viewing to the larger channel to avoid anomalies.
In the current situation, where news channel output is being simulcast across several channels, ratings comparisons between news channels should be made with care. In particular, the published ratings for BBC News 24, which is currently simulcasting a considerable proportion of its output, will not fully represent the viewing audience to this channel.
No viewing is lost to the system, however, and the total audience for simulcast programmes across platforms and channels will be correct.