Promoting Research Literacy for Improved Patient Outcomes

Measures of central tendency in chaplaincy, health care, and related research

The three measures of central tendency are discussed in this article: the mode, the median, and the mean. These measures of central tendency describe data in different and important ways, in relation to the level of measurement (nominal, ordinal, interval, or ratio) used to obtain the data. The results of published research studies, thought experiments, and graphs of frequency and percentage distributions of data are used as examples to demonstrate and explain the similarities and differences among these summary measures of data. The examples include the application of nominal, ordinal, interval, and ratios scales to measure pain, anxiety, chaplaincy services, religious behaviors, and treatment-related preferences, and their respective measures of central tendency. Examples of unimodal and bimodal distributions, and differences in the relative locations of the median and mean in symmetrical and skewed distributions are also presented and discussed.