Summary & Self-Check

Descriptive studies are useful for:

Thinking man icon indicating questions for the student to answer


An article in the New York Times made the following observation: "Mississippi is first among states in percentage of children who are obese, according to the Kaiser Family Foundation. It is first in rates of heart disease, second in the number of adults with diabetes, second in adult obesity, near last in the percentage of adults who participate in physical activity, near last in fruit and vegetable consumption and dead last in life expectancy."

With regard to these observations about the relationship of heart disease and diabetes to diet and physical activity, which study type do these observations most resemble?



An ecological study of the relationship between per capita soft drink sales and annual mortality from diabetes in the 50 US states may produce misleading results because you cannot tell if individuals who died from diabetes drank more soft drinks than individuals who did not die from diabetes.



A cross-sectional study of the relationship between eye color and the risk of cataracts may produce misleading results because you cannot discern the correct temporal relationship between the exposure of interest (eye color) and the outcome (cataracts).