**Question:** Unit of study in Randomised control trial is

A. Patient
B. Disease
C. Intervention
D. Outcome

**Core Concept:** A randomized control trial (RCT) is a study design that compares the effectiveness of two or more interventions or treatments by randomly assigning participants or patients to each group. The primary unit of study in an RCT is the individual patient, also known as a participant.

**Why the Correct Answer is Right:** In an RCT, the focus is on comparing the effects of different interventions on individual patients. By randomly assigning patients to different treatment groups, the study aims to minimize bias and ensure that the observed effects are due to the actual interventions being compared, rather than other confounding factors.

**Why Each Wrong Option is Incorrect:**

A. Patient (Option A): Although patients are the subjects of the study, the correct answer should emphasize their role as the unit of study.
B. Disease (Option B): A disease is the condition being studied, not the unit of study in an RCT.
C. Intervention (Option C): This option is partially correct but the focus should be on the individual patient as the unit of study.
D. Outcome (Option D): Outcomes are the results measured in an RCT, not the unit of study.

**Clinical Pearl:** In clinical research, randomized control trials help establish causality and provide high-quality evidence for treatment decisions. By focusing on individual patients, RCTs enable researchers to evaluate the effects of interventions on health outcomes and guide clinical practice.

**Correct Answer:** . Patient