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:

Gray Matter

Regions of the brain and spinal cord consisting primarily of neuronal cell bodies, dendrites, unmyelinated axons, and glial cells, involved in muscle control and sensory perception.

Nuclei

The central and most important parts of an atom, or a cell's structure that contains the genetic material.

Resting Membrane Potential

The electrical charge difference across the cell membrane when the cell is in a non-excited state.

Local Potential

A temporary, localized change in resting potential, usually occurring in neurons, that can lead to an action potential if it reaches threshold.