In McTigue v University Hospital Bristol NHS Foundation Trust [2016] IRLR 742 EAT, the EAT held that, in order for a claimant to be a "worker" within the meaning of the extended "whistleblower" definition in s.43K of the Employment Rights Act 1996, all that is required is that the end user substantially determined the terms under which the claimant carried out his or her work. It is not necessary to show that the end user determined those terms to any greater or lesser degree than the agency, of whom the claimant might also be an employee or worker.