However, there are geographic variations on this and they're quite strong.
但是，这方面存在很大的地域差异。
英语百科
Unwarranted variation
Unwarranted variation (or geographic variation) in health care service delivery, first so termed by Dr. John Wennberg, refers to differences that cannot be explained by illness, medical need, or the dictates of evidence-based medicine. It can be caused by shortfalls in three areas: