Professional qualifications for Civil Aviation Medical Examiners?

[Carrier]

I would like to know what the abbreviations below stand for, and the names and addresses of the organisations that issue these designations. I have tried a Google search but have not found the answers They must be some sort of rather obscure minor professional memberships to not show up readily on Google. If so, do their members have to earn these designations by meeting required minimum examination and experience standards or do they become members merely by paying application and annual membership fees?

MDCM

CCFP(EM)

D.Av.Med.

Thanks for any info.