The Office of Fair Trading has said that it had launched a joint consultation with the Competition Commission to create a good practice guide for parties presenting evidence in merger inquiries.

The OFT said that a draft guide contained advice on how to design and present consumer survey evidence, sets out several principles of good survey design and details a range of practices that should increase the evidential weight that can be given to survey results.

In particular the OFT said it was seeking responses from parties likely to advise those involved in merger inquiries, for example legal firms, management consultancies, economic consultancies and market research agencies.

Steve Brown, the OFT's Head of Statistics and Secretary of the joint OFT/CC drafting group, said, "Submissions derived from consumer surveys can form an important part of the evidence in a merger investigation. The final guide will ensure that parties who wish to provide survey evidence have as much practical assistance from the CC and OFT as possible."

The OFT said that parties interested in giving their views on the draft guidance had until 3 September 2010 to do so. The final guide is expected to be published by the end of the year.