Evidence-Based Practice for Nurses

reported in the workplace among adult males. In 2012, the number of

rubella cases sharply increased to 2,392, with the rise in cases continuing

into 2013. From January 1 to May 1, 2013, a total of 5,442 rubella cases

were reported. (CDC, 2013b)

These data demonstrated short-term trends in the number of reported cases

of the rubella virus in Japan that were in excess of normal expectancy. As a

result, health officials deemed that Japan was experiencing a nationwide ru-

bella epidemic (CDC, 2013b). As a result of these findings, Japan initiated a

country-wide education and immunization campaign focused on households

with pregnant women to further protect this population from contracting

rubella because of the risks to the unborn child (CDC, 2013b).

KEY TERM

pandemic:

Epidemic that has

spread worldwide

1. Diseases that occur over long periods of time are known as:
   a. cyclical changes.
   b. intermittent trends.
   c. secular trends.
   d. short-term trends.


2. Diseases that spread around the world are known as:
   a. endemic.
   b. epidemic.
   c. international outbreak.
   d. pandemic.

TEST YOUR KNOWLEDGE 8-4

How did you do? 1. c; 2. d

8.5 Descriptive Study Designs

By the end of this section, you will be able to:

‹ Describe descriptive study designs, including case reports and series, ecologic studies,

and cross-sectional studies

‹ Construct a 2 × 2 data table

‹ Calculate a prevalence ratio for a cross-sectional study design

Descriptive study designs are hypothesis-generating and are used to examine

different types of phenomena. These studies include case reports or series,

ecologic studies, and cross-sectional studies.

204 CHAPTER 8 Epidemiologic Designs: Using Data to Understand Populations