Which of the following is a limitation of cross-sectional studies?

Cross-sectional studies are designed to assess a population at a single point in time, which means they capture a snapshot of data, including health outcomes and exposures. However, this design inherently limits the ability to determine the sequence of events, known as time-order.

Time-order confusion arises because, in a cross-sectional study, researchers do not know whether the exposure to a risk factor occurred before or after the development of the disease or outcome. For example, if a study finds that individuals with higher levels of a certain behavior (like smoking) are also more likely to have a specific health condition (like lung disease), it remains unclear whether the smoking led to the lung disease or if the outcome influenced the behavior.

Due to this limitation, while cross-sectional studies can help identify associations, they cannot establish causality. Understanding this helps explain why time-order confusion is a critical limitation of such studies, underscoring the gap between correlation and causation in research findings.