National EMSC Data Analysis Resource Center
A descriptive study design is one in which your primary goal is to assess a sample at one specific point in time without trying to make inferences or causal statements. In general, there are three primary reasons to conduct descriptive studies:
Descriptive studies are helpful in revealing patterns and connections that might otherwise go unnoticed. We’ll discuss two types of descriptive studies:
A descriptive case report study is a detailed profile of a subject or set of subjects and their clinical or laboratory experience. The purpose of these studies is to identify potential areas of research and generate interest and hypothesis formulation.
One case report study led to the eventual discovery of HIV.Case reports are a first step for providing clues to identifying a new disease or adverse health effect from an exposure or clinical experience. A classic example is the case report study of 5 homosexual males who developed a rare pneumonia. This case report study led to the eventual discovery of HIV. Case reports are most likely to be useful when the disease or condition is uncommon and when the disease or condition is caused almost exclusively by a single kind of exposure.
A descriptive cross-sectional study is a study in which the disease or condition and potentially related factors are measured at a specific point in time for a defined population. Cross-sectional studies can be thought of as a "snapshot" of the frequency and characteristics of a condition in a population at a particular point in time.
This type of data can be used to assess the prevalence of conditions in a population. However, since exposure and disease status are measured at the same point in time, causal statements should not be made from this type of study. It is usually not possible to distinguish whether the exposure proceeded or followed the condition.