The broken line used in a diagram for a cohort design indicates that the two groups in the design are successive cohorts and not nonequivalent groups.

Cohort Design

A research design that follows a group (cohort) of individuals over time to study changes and outcomes, often used in epidemiology and social sciences.

Broken Line

Describes a line in graphs or diagrams that is interrupted at intervals to signify discontinuity or different conditions.

Successive Cohorts

Groups of subjects sequentially assessed over time, often used in longitudinal studies to observe changes within a population.