Biostatistics & Research · single question
Which study design provides the highest level of scientific evidence?
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Correct answer: B. Randomized Controlled Clinical Trial (RCT)
✓ B) Randomized Controlled Clinical Trial (RCT) is correct.
The evidence hierarchy (from highest to lowest): Systematic review/meta-analysis > RCT > Controlled trial (non-randomized) > Cohort study > Case-control > Case series > Case report > Expert opinion. RCTs minimize bias through randomization and controls, providing the strongest evidence for causation. A single RCT is the highest level listed in this question. Literature reviews (narrative) are lower quality than systematic reviews.
The evidence hierarchy (from highest to lowest): Systematic review/meta-analysis > RCT > Controlled trial (non-randomized) > Cohort study > Case-control > Case series > Case report > Expert opinion. RCTs minimize bias through randomization and controls, providing the strongest evidence for causation. A single RCT is the highest level listed in this question. Literature reviews (narrative) are lower quality than systematic reviews.
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