If D₁ and D₂ Are the Observed Deaths in the Two

question 12

Multiple Choice

If D₁ and D₂ are the observed deaths in the two groups while E₁ and E₂ are the expected number of deaths for the two groups, which of the following is the correct equation for the hazard ratio?

• A) HR = ( D₁/D₂ ) / ( E₁/E₂ )
• B) HR = ( D₁/D₂ ) / ( E₂/E₁ )
• C) HR = ( D₂/D₁ ) / ( E₁/E₂ )
• D) HR = ( D₂/D₁ ) / ( E₂/E₁ )

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Definitions:

Left Ventricle

The chamber of the heart that receives oxygenated blood from the left atrium and pumps it out to the body through the aorta.

Aorta

The largest artery in the body, originating from the left ventricle of the heart and extending down to the abdomen, supplying oxygenated blood to the circulatory system.

Pulmonary Trunk

The major blood vessel transporting deoxygenated blood from the right ventricle of the heart to the lungs.

Pacemaker Potential

Pacemaker potential refers to the spontaneous gradual depolarization of the membrane potential in pacemaker cells, leading to the initiation of action potentials in certain heart cells.