Footnotes

• All authors are members of the Cambridge Coma Study Group

• Authors’ contributions:

  L Elliott—Principal investigator (data acquisition and patient recruitment).

  A Shiel—Data acquisition and patient recruitment.

  M Coleman—Data analysis and manuscript preparation

  B Wilson—Project supervision.

  D Badwan—Patient recruitment and data analysis.

  D Menon—Project supervision.

  J Pickard—Project supervision.

• This work was funded by the Smiths Charity, the fund for Addenbrooke’s and an MRC programme grant (number G9439390 ID 56833).

• Competing interests: none declared