In a double-blind RCT, 'allocation concealment' refers to:

• A Keeping participants unaware of which treatment group they are in
• B Ensuring the person enrolling participants cannot predict upcoming treatment assignments ✓
• C Blinding the outcome assessor
• D Masking the statistical analyst from knowing group identities

Explanation

Allocation concealment prevents the person enrolling/recruiting participants from knowing or predicting the next treatment assignment, eliminating selection bias during enrollment. It ensures that pre-randomization decisions (like whether to enroll a patient) are not influenced by knowledge of upcoming allocation. This is distinct from blinding (which occurs post-allocation). Methods include central randomization, sequentially numbered sealed envelopes, and pharmacy-controlled allocation.

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.