Random assignment vs. random sampling
Randomly assigning participants to the treatment and control conditions mainly strengthens:
Answer A: explanation for every choice
A
Correct. Random assignment balances confounding variables across groups, supporting causal conclusions.
B
External validity, or generalizability, depends on random sampling from the population.
C
Test–retest reliability concerns the consistency of a measure over time.
D
Construct validity concerns whether a measure captures the intended concept.
TakeawayRandom sampling → external validity. Random assignment → internal validity.
Next question →
Reviewed 2026-11-05 by a medical student. Spot an error? Report it with question ID ps145.