Maybe USA people DO cough differently ?!, page-4

This question has been asked – and answered – many times, both by the company and in this forum.  And your post reads like a statement rather than a question.  So a somewhat sarcastic response from somebody is almost inevitable.

Early studies were conducted in Perth and Indonesia.  Linguistic and cultural differences have been ruled out as a factor by the results.  If you get somebody to open their mouth and say "ah" you get the same sound regardless of where the person is from.  

The sound signatures captured by ResappDx come from the lungs, and reflect the physiology of the lungs rather than the vocal organs.