Hi Dick,
The point I make about validation of exams is that the exam must be tested on a statistically valid & representative population
prior to release if a percentage cut-off is to be used for pass/fail assessment.
If that hasn't been done then the exam must be graded on a curve ie using
x standard deviations for the candidates sitting that particular exam/question combination.
Only after adequate numbers have sat the exam can the percentage cut off be correlated with the standard deviation.
AFAIK the exams were introduced on Day 1 with an already set percentage pass mark. When were they tested against the candidate population to establish the percentage?