What condition is responsible for the majority of prehospital deaths from myocardial infarction?

Myocardial infarction has a poor prognosis without quick intervention. The risk of prehospital death is compounded manifold by the presence of type 2 diabetes. This is because of the effects of diabetes on circulation, causing increased fluid buildup in the chest. Moreover, type 2 diabetes is often accompanied by obesity which has similarly disastrous effects of the movement of blood and lymph.

Very hard to understand

When scientist examine data such as historical documents, they are using the "scientific methods"