I was reading a research article and came across this:
We studied 55 outcomes of interest, including both effectiveness and safety endpoints. We divided effectiveness outcomes into three primary endpoints (ie, acute myocardial infarction, hospitalization for heart failure, and stroke, on the basis of their use in the 2017 AHA/ACC Guidelines systematic review), and six secondary effectiveness outcomes that major hypertension treatment RCTs have considered.3, 9, 10 The 46 safety outcomes were antihypertensive drug side-effects, including angioedema, cough, electrolyte imbalance, gout, diarrhea, and kidney disease.
My questions
I understand drug is said to be effective if it meets the purpose for which it was designed (ex: taking the drug cures the disease). What does primary endpoints mean in this context?
What does secondary effectiveness outcomes mean?
What are safety outcomes? Why are drug side-effects considered as safety outcomes?