What is an example of a primary study?

A primary study refers to original research that collects data directly from participants or experiments. Cohort studies fit this description as they follow a group of individuals (a cohort) over time to observe outcomes such as disease development based on exposure to certain risk factors. This type of study generates new data rather than summarizing or analyzing data collected from other studies.

Systematic reviews and meta-analyses compile and synthesize existing research studies, providing broader insights but not producing new primary data themselves. Case studies, while they can be instrumental in exploring specific instances in detail, are typically focused on an individual or a small group rather than a cohort, and they do not generalize findings like cohort studies do. Therefore, cohort studies are a clear example of primary studies as they establish a direct link between exposures and outcomes through newly collected data.