What is a cross-sectional study?
A cross-sectional study is a descriptive study in which disease and exposure status are measured simultaneously in a given population. Cross-sectional studies can be thought of as providing a "snapshot" of the frequency and characteristics of a disease in a population at a particular point in time. This type of data can be used to assess the prevalence of acute or chronic conditions in a population. However, since exposure and disease status are measured at the same point in time, it may not be possible to distinguish whether the exposure preceeded or followed the disease, and thus cause and effect relationships are not certain.