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Author Question: Which level of constraint allows us to draw causal inferences with confidence? A) Differential ... (Read 31 times) |
It is widely believed that giving a daily oral dose of aspirin to heart attack patients improves their chances of survival because the aspirin blocks the formation of new blood clots.
Serum cholesterol testing in adults is recommended every 1 to 5 years. People with diabetes and a family history of high cholesterol should be tested even more frequently.
Before a vaccine is licensed in the USA, the Food and Drug Administration (FDA) reviews it for safety and effectiveness. The CDC then reviews all studies again, as well as the American Academy of Pediatrics and the American Academy of Family Physicians. Every lot of vaccine is tested before administration to the public, and the FDA regularly inspects vaccine manufacturers' facilities.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.