What is the primary way to reduce information bias in a study?

Correct Answer: B

Rationale: Blinding (B) reduces information bias by masking status (e.g., double-blind trials). A, C, and D address other issues.

Correct Answer: C

Rationale: Higher specificity (C) boosts PPV by reducing false positives (e.g., stricter test). A helps, B and D don’t directly.

Correct Answer: C

Rationale: Quarantine (C) isolates early cases (secondary). A and D are primary, B is treatment.

Correct Answer: A

Rationale: Confounder (A) affects exposure-outcome links (e.g., age). B is error, C is bias, D is a response.

Correct Answer: C

Rationale: A and B reflect higher perforation at age extremes. D and E align with surgical outcomes. C is false—leukocytosis indicates severity, not perforation risk directly.