Ruth-Whittington-CEO-Medical-CommunicationsRegionalisation of phase IV trials because of payer differences sounds like a good thing in the short term.  Improved market access, for one.  But has anyone considered the longer term effects – the inability to combine trial data and thus determine subtle effects that may only be noticeable in larger populations and in the longer term? Meta-analyses and complex statistics can resolve some of the issues with differing trial designs, but the data are less robust. We may live to regret increasing regionalisation for the lack of the bigger picture.