Study design
Observational study
A study where researchers observe exposures and outcomes without assigning the intervention.
What it means
Definition
Observational study. An observational study can detect patterns in real-world populations, but it is vulnerable to confounding and bias. It is usually better for generating hypotheses than proving direct causation.
What it can tell you
It can help separate an observed association from a tested causal claim.
What it cannot tell you
It cannot remove confounding or prove causation without stronger study design and analysis.
Headline trap
Why this matters in headlines
If people who eat a food have lower disease rates, the food may not be the cause.