What is a Cohort?

A cohort is a group of clinical trial participants who share common characteristics or receive the same intervention as part of a study. Participants may be assigned to cohorts based on factors such as treatment dose, disease type, age group, or study phase to support structured evaluation and comparison during the trial.

Cohorts are commonly used to organize participants into predefined groups for enrollment, treatment, or analysis. Depending on the study design, participants may enter different cohorts sequentially or simultaneously to evaluate treatment safety, efficacy, dosing, or other study objectives.

Using cohorts helps study teams manage participant groups more efficiently while ensuring that protocol-defined interventions and assessments are applied consistently within each group.

During study setup, study teams can configure protocol-defined cohorts, participant allocation rules, visit schedules, and treatment workflows within Clinion’s unified eClinical platform based on study requirements. These configurations help ensure that participants are assigned and managed according to the study protocol.

Connected systems such as EDC, CTMS, and RTSM can remain aligned with cohort-specific activities, helping study teams maintain consistent participant management, treatment tracking, and study oversight throughout the trial.

A Phase I clinical trial may evaluate three dose levels of an investigational drug. Participants are enrolled into separate cohorts, with each cohort receiving a different dose. After safety data from the first cohort is reviewed, enrollment may begin for the next cohort according to the study protocol.

Dose Escalation
Randomization
Study Arm
Clinical Trial Protocol
Subject Enrollment
Adaptive Trial Design

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