A raft of reforms aimed at standardising trading in complex credit derivatives, which came into force last month and have been largely hailed as a success, are failing to address the root cause of the problems that have engulfed these markets since Lehman Brothers collapsed, according to a prominent US consultancy.

In a report entitled 'The Big Flaw of the CDS Big Bang', Kevin McPartland, a senior analyst at Massachusetts-based consultants Tabb Group, warns that the new framework for trading in these markets has thrown up potential conflicts of interest among participants.