Which of the Following Is a Threat to External Validity

question 35

Multiple Choice

Which of the following is a threat to external validity in a longitudinal design?

• A) attrition
• B) uniqueness of the study environment
• C) practice effects
• D) cohort effects

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Definitions:

Nasal Congestion

The blockage of the nasal passages typically due to inflammation of the membranes lining the nose from infection or allergies.

Pulmonary Embolism

A blockage in one of the pulmonary arteries in the lungs, typically caused by blood clots that travel to the lungs from the legs or other parts of the body.

Pulmonary Edema

A condition characterized by excess fluid accumulation in the lungs, often leading to difficulty breathing.

Pneumothorax

The presence of air or gas in the pleural cavity. The lung typically collapses with pneumothorax.