What is a key limitation of case reports?

• A. Randomization of subjects
• B. Double-blind design
• C. Large sample size
• D. Inherent lack of control and limited generalization

Answer: (D)

Case reports describe one or a few patients in detail, without a comparison group. Because there’s no control and no randomization, you can’t tell whether the observed outcome is due to the intervention or other factors. This means the findings can’t be generalized to a broader population because they may reflect unique aspects of a single case. Other study designs include randomization, blinding, and larger samples precisely to reduce bias and allow results to apply more broadly. So the main limitation is the inherent lack of control and the limited ability to generalize beyond the individual case(s).