The UK's state broadcaster, the BBC, is preparing its response to a report endorsing its contribution to the evolution of digital radio but raising questions about its impact on commercial providers.

The independent review, for the Department of Culture, Media and Sport, was carried out by Tim Gardam, former director of commercial TV station Channel Four, who says: "The scope and ambition of the BBC's digital radio services have evolved well beyond what was initially envisaged when they were granted approval.

"This is a considerable achievement that has been instrumental in promoting the uptake of digital radio."

The report looked at the new stations, 1Xtra, BBC6, BBC7, BBC Asian Network and Five Live Sports Extra.

But, adds Gardam: "The challenge now is to give the BBC's digital channels the room to evolve further, while ensuring that they remain distinctive from the services offered by the commercial radio market."

"This is the key to ensuring a healthy digital radio market across the PSB and commercial sectors."

He points out that the success of BBC7, a channel devoted to drama, comedy and children's programming, led to a downturn in the fortunes of Oneword, a commercial digital station formerly owned by the Guardian Media Group.

The station, now 50% owned by UBC Media, is still broadcasting but in a different format. Gardam says the situation might have been avoided if the BBC had been made to share its considerable broadcast archive material.

Says the BBC: " These are important issues…We will consider carefully all the review's recommendations before responding to the Secretary of State in November."

Data sourced from; additional content by WARC staff