The concept of “Standard of Care” is a bit subjective. See this wikipedia entry for more, but the basic idea is that the standard of care is what any competent physician would do for that particular patient in that particular situation. This can vary somewhat with local practices. The American College of Gastroenterolgy provides clinical guidelines that GI’s can use along with their clinical experience and professional judgment to determine the course of treatment for your IBD. The ACG publishes these guidelines as a list on their website. You can find the list of guidelines here. Scroll down for the Crohn’s and colitis entries.
Of course other nations have their own professional associations:
Here is a guideline published by GUT, an International Journal of Gastroenterolgy and Hepatology in 2004.
Perhaps these published guidelines will be helpful when you are trying to understand the advice of your physician.