YSK if you are in the U.S. and have health insurance through your employer, there's a 2/3 chance that your employer dictates what's covered and not covered - not the health insurance company.
from /r/YouShouldKnow
YSK如果你在美國，並通過你的僱主購買醫療保險，有2/3的機會你的僱主決定了什麼是承保和不承保--而不是醫療保險公司。