How can study design contribute to misleading conclusions?

The design of an epidemiological study is crucial in determining the validity of its conclusions. Cross-sectional studies, for example, can only provide a snapshot in time and cannot establish causality. Case-control studies may be prone to recall bias, where participants with a particular outcome may remember their exposures differently than those without the outcome. Even randomized controlled trials (RCTs), considered the gold standard, can yield misleading conclusions if there is poor randomization or lack of blinding.