Does the material always explain what the numbers mean?

Provide reasons why the numbers in the material are important to the main message and the audience’s understanding of the information. As with words, numbers can mean different things to different people. Some numbers may seem significant and worrisome to one group of people and insignificant to another group. Many people –even health professionals – have difficulty interpreting and extracting a meaningful “bottom line” from numbers.

To help people make sense of numbers, present them in context. Is the number high or low for this type of health issue or higher or lower than expected? Is the number important for an individual to know about and act on or a number describing a health outcome in a large group of people?

CDC often shares “case counts” for many different diseases. This epidemiologic information often shows the place and time for “cases,” meaning a person who got sick from a particular disease or met a particular definition of a disease or condition. There should always be a description of what these numbers mean to individual or population health.

  • MORE OR LESS: For example, one case of a rare infectious disease might be cause for alarm and immediate public health action while many cases of a common infectious disease may not be alarming.
  • EXPECTED OR NOT: For example, a disease appears in an unexpected place versus a place where the disease may be common. Sometimes, a disease can occur at a time of the year that is different than what has happened in the past, such as flu season starting early.

Avoid using qualitative descriptors, such as high and low or large and small, by themselves. When you use qualitative descriptors, you must also provide the number and explain the meaning.

Example 1:

The amount of meat recommended as part of a healthy meal is 3 to 4 ounces – it will look about the same size as a deck of cards.

Example 2:

Radon is a poisonous gas. Testing your home is the only way to know if you have a radon problem. If your home has a radon level of 4 or higher, you will need to make a plan to fix your home. This much radon is unhealthy for you and your family. If radon levels are between 2 and 4, you may want to fix your home. No level of radon is safe.

Example 3:

About 1 in 8 women in the United States will get breast cancer in her lifetime. That’s a very high number of women. In fact, after skin cancer, breast cancer is the most common type of cancer in women.

Page last reviewed: August 11, 2014