Hi Jitu,
I too got the instruction to do the medicals within India.
I sent an email to NDVO asking for clarification as I am in Toronto and they replied in 8 business days. They attached few additional documents with details of my name, file number and all those... (they were the same documents that DMP had and they filled the information manually). In my case, they attached the additional documents along with the package they were planning to send it to Ottawa (I did my medicals before getting the response from NDVO).
I attached normal passport photographs, they just asked for 2 photos and no size restriction. They are not particular about the photo size (Any wallet size photo will do).
Doctor John (666 Burnhamthorpe Road West, Mississauga) was good, the visit took around 2 hours. Dr Fees - $120 and they sent me to another X-Ray lab where they charged me $36. So, total $156 for adults and 110 for kids. Nothing special that needs to be observed before the medical exam.
Let me know if you need more details.
Thanks,
Mikey