The best and worst ­performing public bodies for revealing details about themselves under freedom of information (FoI) are to be named this month.

The Scottish Information Commissioner, Rosemary Agnew, will identify those organisations most adept at complying with requests for details under legislation.

This will happen ahead of a report early next year backed by research which will challenge ministers to increase the range of bodies subject to public information rights.

The Commissioner, in an annual report, highlighted a slippage in the way public bodies respond to their legal obligations, saying that nearly a decade into the FoI era, progress must be expected. But Ms Agnew said there are two new developments which should put pressure on public bodies and the Government to increase the momentum on those covered by public information rights.

Her annual report showed that appeals against the Government almost doubled from 16% last year to 31% this year, but she said unless we know the level of requests this does not tell us much.

That is the kind of rounded information Ms Agnew is looking to raise, with a new database appearing this month which will show how every public body is responding to requests.

She stressed this was "not intended to name and shame" and was best seen as a tool to help all public bodies assess how they were measuring up to similar bodies and authorities.

Better, she said, was seeing it as a benchmarking exercise where bodies could rank themselves against similar bodies and learn from good practice.

The database will appear this month, and by next March Ms Agnew will publish a report on the direction of FoI, including future extensions to the regime.

Ms Agnew welcomed the recent addition of council culture and recreation departments to the bodies compelled to adhere to FoI rules, but she made it clear she wants the number of such bodies to increase.