Which of the Following Is a Threat to the Internal

question 40

Multiple Choice

Which of the following is a threat to the internal validity of studies using one-group pretest-posttest design?

• A)Cohort effects
• B)Statistical regression
• C)Propensity score matching
• D)Selection bias

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Definitions:

Mammal Species

A group within the class Mammalia, characterized by the presence of mammary glands, hair, and three ear bones, among other features.

Virus

A tiny infectious agent that replicates only inside the living cells of other organisms, affecting all types of life forms.

AZT

Azidothymidine, a medication used to prevent and treat HIV/AIDS, it works by inhibiting the enzyme reverse transcriptase.

HIV Life Cycle

The series of steps the HIV virus takes to replicate and infect host cells, including attachment, fusion, reverse transcription, integration, replication, assembly, and budding.