A cross-over trial design where each participant receives both treatment A and treatment B in sequence is most appropriate for studying:
- A Acute infection treatment where disease resolves permanently
- B Surgical interventions
- C Chronic stable conditions where washout between treatments is feasible ✓
- D Preventive vaccines requiring long-term immunity assessment
Correct answer: C. Chronic stable conditions where washout between treatments is feasible
Explanation
Cross-over trials are best suited for chronic stable conditions (e.g., stable angina, chronic pain, stable asthma) where the disease state is unlikely to change dramatically, a washout period between treatments can be used, and participants can serve as their own controls. They are inappropriate for curable diseases (condition no longer present for the second period), surgical interventions (irreversible), or vaccines (immunity persists across periods).
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.