Are the standards of care in Canada and the U.S. different with regard to ordering CT scans for minor head trauma? Does practicing defensive medicine ignore evidence-based best practice or is it just our American reality.

A hemodynamically stable middle-aged male presents to your ED with non-pleuritic chest pain and multiple cardiac risk factors. Your diagnostic evaluation includes includes a Troponin-I which unfortunately returns at 0.5 ng/mL, although no ECG changes are noted.