Evidence-Based Practice for Nurses

When there is greater variation in data, a wider spread results. In graphic rep-
resentations of data (see Figure 13-5), highly uniform data have a high peak
and highly variable data have a low peak. Kurtosis is the term used to describe
the peakedness or flatness of a data set.

Mean

Scores on test

Number of students

Median

Mode

FIGURE 13-3 Example of a Negatively Skewed Distribution

Mean

Scores on test

Number of students

Median

Mode

FIGURE 13-4 Example of a Positively Skewed Distribution

KEY TERM

kurtosis: The

peakedness or

flatness of a

distribution of data

13.4 Distribution Patterns 343