Hello Arvind,

Interesting question asked.Such a field exist, I was not aware of. Thanks to your query, I was able to research on the said topic.

First a brief description of what a Medical coder does. 

Have you heard about medical claim or Medical Insurance, especially after a surgery is done. We as a patient, submit the required documents to the insurance company. But does the person just gives us insurance seeing our bills? Or do they check through each of our medical papers and then decide whether claim has to be given or how much claim has to be provided.

Here is where a medical coder, comes into play. He goes through the patients records, as in when the patient came for diagnosis, condition at the time of checkup, doctors prescription, surgery details, medications used pre and post surgery etc. He then assign a code, which is already existing in a database for a particular diagnosis. He then sends it to the the Insurance companies and claims work faster.

Read in more details on this website:

https://www.aapc.com/medical-coding/what-does-a-medical-coder-do.aspx

As far as the scope is concerned, someone only with knowledge of the medical terminology, like say a Pharmacist or a doctor or a paramedical person only can opt for this job. Knowledge of computers is a must. Flare for reading and language proficiency is a must. Must know different languages. As such these days very citizen goes for an Insurance claim, this profession of a Medical coder is very much in demand.

Hope this answers your query.

Wish you good luck...