Who determines the amount of and kind of diagnostic tests allowed for a medical condition?

Answer 1

Usually a physician.

Answer 2

The common perception is that it's the physician but in many cases it's the patient's medical insurance company. There is also a proposal in congress put forth by Tom Daischle that aims to set up a government agency to make those decisions in an effort to control health care costs.
Scary, isn't it.

Answer 3

Thank you..that is actually the answer i had i just wanted to be sure =)