“52. In my assessment the fundamental principles to be derived from these cases and to be applied by tribunals where credibility is in issue may be summarised as follows: (1) there is no formal requirement that a claimant's evidence be corroborated – but, although it is not a prerequisite, corroborative evidence may well reinforce the claimant's evidence; (2) equally, there is no obligation on a tribunal simply to accept a claimant's evidence as credible; (3) the decision on credibility is a decision for the tribunal in the exercise of its judgment, weighing and taking into account all relevant considerations (e.g. the person's reliability, the internal consistency of their account, its consistency with other evidence, its inherent plausibility, etc, whilst bearing in mind that the bare-faced liar may appear wholly consistent and the truthful witness's account may have gaps and discrepancies, not least due to forgetfulness or mental health problems); (4) subject to the requirements of natural justice, there is no obligation on a tribunal to put a finding as to credibility to a party for comment before reaching a decision; (5) having arrived at its decision, there is no universal obligation on tribunals to explain assessments of credibility in every instance; (6) there is, however, an obligation on a tribunal to give adequate reasons for its decision, which may, depending on the circumstances, include a brief explanation as to why a particular piece of evidence has not been accepted. As the Northern Ireland Tribunal of Commissioners explained in R 3/01(IB)(T), ultimately ‘the only rule is that the reasons for the decision must make the decision comprehensible to a reasonable person reading it’.” 18. In the present case it is important to note that the First-tier Tribunal did not simply make a bald finding that the appellant was not a credible witness. In addition it gave some brief reasons for reaching that conclusion (see paragraph 8 above). In many cases, especially on a new claim, that may well be sufficient to dispose of the matter. 19. However, context is everything when assessing the adequacy of reasons, as noted by the Tribunal of Social Security Commissioners in Northern Ireland in decision R 2/01(IB)(T) . The present case was one in which the appellant’s account had plainly been accepted by Dr Ao in July 2007 but equally had been disbelieved by Dr Kithan in November 2008 and by the tribunal in July 2009. In those circumstances I take the view that a rather fuller explanation was warranted than that provided by this tribunal. 20. Furthermore, the tribunal’s conclusion was that “there was no objective evidence to support the Appellant’s story which was not believed by the Tribunal and consequently the appeal failed”