When to use an observational study?

An observational study is used when researchers want to investigate relationships or effects in real-world settings without manipulating variables, which is often impractical or unethical. It's suitable for exploring associations between exposures and outcomes, especially in fields like public health or Social Sciences. These studies are also beneficial when randomization isn't possible, such as studying the effects of lifestyle factors on health outcomes. However, they may be limited by confounding variables and cannot establish causation definitively.