If you are a Canadian citizen without US green card or US citizenship then I strongly advise you to NOT apply to any international medical school. The Canadian government has put a cap on how many Statement of Need (SON) documents that will be issued.
In order for the ECFMG to sponsor your J-1 visa, you need a SON from the Canadian government to be sent to ECFMG. The SON is needed because after you finish your residency training or fellowship, you are to return to Canada and stay there for 2 years before you are allowed to come back to the US for a job.
The only way to get around this is you are already in Caribbean medical school is to do your USMLE Step 3 and apply for H-1B visa with the programs that sponsors it. Or find some way to get a US green card or US citizenship so you can increase your chances of getting a residency.
For those Canadians who will apply this year, if they match then they will have to apply for SON, and if they don’t get approved for an SON then they will loose their residency spot.
Please be informed before applying, and if your are a Canadian citizen already in an international medical school, then start preparing now. Unless you know you will get a residency spot in Canada, then don’t worry about it.
I hope this helps and good luck.
Here is the link of the Canadian source of the number of SONs that will be given per specialty for the 2016 residency year.