The lethality of MI

 Validity of Emergency Room criteria for Myocardial Infarction A majority of people undergoing an acute myocardial infarction {MI) experience chest pain, however most patients with chest pain have another reason for their symptoms. Because of the lethality of MI though, many physicians hospitalize patients presenting with chest pain until MI can be confirmed or ruled out. In an attempt to avoid hospitalization of patients with chest pain but not infarction. several investigators developed clinical criteria to better predict the presence of MI. For all patients presenting to an emergency room with chest pain, several patient characteristics were collected and new emergency room criteria were developed to predict MI. The validity of this new criteria was compared against the gold standard to determine the presence of MI including electrocardiographic (ECG) changes, elevated serum levels of cardiac enzymes, or abnormalities in radionuclide testing. The results of the validation study are presented below: -A. Calculate the prevalence of MI in this population. -B. Calculate the sensitivity of the ER criteria as a test for MI. -C. Calculate the specificity of the ER criteria as a test for M1. -D. What is the probability that someone with an M1 will be categorized as “Negative" by the ER criteria? -E. What is the probability that someone without MI will be categorized as “Positive" by the ER criteria? -F. Given someone has been categorized as “Positive" by the ER. criteria, what is the probability that they actually have an M1? -G. Given someone has been categorized as “Negative" by the ER criteria, what is the probability that they actually do not have an M1? -H. In an attempt to capture more patients with potential MI, it is suggested that this ER criterion should be applied to all patients presenting to the ER. What are the implications of this decision?

Show less