Reliability of Stress Tests?

http://www.heartsite.com/html/regular_stress.html

What is the reliability of a Regular Stress Test?
If a patient is able to achieve the target heart rate, a regular treadmill stress test is capable of diagnosing important disease in approximately 67% or 2/3 rd of patients with coronary artery disease. The accuracy is lower (about 50%) when patients have narrowing in a single coronary artery or higher (greater than 80%) when all three major arteries are involved. Approximately 10% of patients may have a "false-positive" test (when the result is falsely abnormal in a patient without coronary artery disease).

[borg42]

Here is the article Toby was referring to. Was sent to me by MysteryChemist several months ago.