GAMCA (GCC) examination???

Hello everybody
I hope you all do good
My situation is somehow urgent. I hope you kind members of forum answer my questions.
I asked some members about the medical examination of work visa and they all mentioned that all they did were tests of HIV, hepatitis and xray for TB.
Does any body know about gamca medical examination? I've read that it is obligatory for any one  who enters Qatar for work.
Thank you very much

Gamma is !association of gulf MEDICAL centre which tell from where to so medical test and they will send medical test directly to immigration