Seeing as the frogs lie about everything elsei...I demand that a British tape measure squad be despathed with immediate effect to verify these stats. Also. How did the bloody poles score so highly? Half of their young men live in Peterorogh.
Penis size records are always contentious, depends on how they're measured, who measures, etc.
It would surprise no one to learn self-reported size is usually bigger than independently collected, but you also have different states of the penis to consider. Apparently, they should be measured when flaccid, but should be stretched as you measure as this accounts for potential growth when erect.
Unfortunately, this isn't standard practice, so different people take different measures making comparisons inaccurate.