A Double-Blind Study of a Vaccine Is One in Which

question 2

Multiple Choice

A double-blind study of a vaccine is one in which:

• A) the study group receives the vaccine and the control group receives a placebo.
• B) neither observers nor subjects know the nature of the placebo.
• C) neither observers nor subjects know which subject receives the vaccine and which receives a placebo.
• D) neither the study group nor the control group knows the identity of the observers.
• E) the control group does not know the identity of the study group.

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Definitions:

Pneumonia

A respiratory condition characterized by the inflammation of the lungs, often caused by bacterial, viral, or fungal infections.

Dementia

A broad category of brain diseases that cause a long-term and often gradual decrease in the ability to think and remember, affecting daily functioning.

Treatment Reverses

The process in which the effects of a previous treatment are negated or reversed, restoring the original condition or symptoms.

Cognitive Impairment

A reduction in mental functions such as memory, attention, and decision-making, affecting an individual's daily life.