How Is Number Needed to Treat (NNT) Calculated

question 14

Multiple Choice

How is number needed to treat (NNT) calculated?

• A) One divided by the absolute risk reduction
• B) Incidence rate of disease in exposed population over the incidence of disease in unexposed population
• C) Event rate in control group minus event rate in experimental group
• D) Number of people with given disease in given population at one point in time divided by the total in given population at same point in time

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Definitions:

Memory Trace

A theoretical concept referring to the physical change in the brain, presumably involved in storing a piece of information or memory.

Physical Change

A change in which the form or appearance of matter changes but not its chemical composition.

Anterograde Amnesia

A condition affecting memory, where new events post-trauma or onset cannot be committed to long-term memory.

Retrograde Amnesia

A loss of memory-access to events that occurred, or information that was learned, before an injury or the onset of a disease.