Understanding Statistics
18 Introduction to Statistics
Lesson
Learning Outcomes
By the end of this chapter, learners will be able to:
- describe how statistics can inform nursing practice,
- differentiate between descriptive and inferential statistics,
- define population and sample, and
- appreciate factors which contribute to data quality.
Statistics In Nursing
There are vast amounts of information available about health and health care. How do we make sense of it? The field of statistics is one tool we can use to help us in collecting, displaying, analyzing and interpreting this information. The use of statistics can be applied to the work of nurses in a variety of ways, in work related to all fields of nursing, such as clinical practice, education, research and management. In all of these areas of nursing, effective use of statistics can support clinical decision making.
It’s likely you have encountered statistics already in your life, but have you understood the meaning of the statistics you were presented with? Would you be able to identify if the way statistics were presented was misleading? The aim of this section of this workbook is to help you begin to understand what statistics represent when you encounter them in your studies. You will be introduced to some basic terms and you will be presented with examples to help you learn about them. As you progress through your nursing program, you may take a course in statistics to learn how to calculate statistics from data sets or learn about more complex statistical methods. Regardless of how you learn about statistics in your program, it is important to build an understand of what statistics represent, in order to use information available to you in an effective manner.
Branches of Statistics
There are two main branches of statistics, descriptive statistics and inferential statistics. Descriptive statistics helps us describe data and can be used to summarize it. This helps turn data sets into useful information which can then inform our nursing work. Inferential statistics helps us to interpret this data by analyzing for relationships between variables. It can help us test hypotheses, make conclusions and make decisions in uncertain situations. In Table 18.1: Ways to Use Descriptive and Inferential Statistics, an example is given to illustrate how these branches work in real life situations.
| Branch of Statistics | Example of Use |
|---|---|
| Descriptive Statistics | To describe the number of primary care physicians and nurse practitioners in each town or city in British Columbia. This could be done by counting the number of primary care physicians and nurse practitioners in each town or city and displaying the numbers for each town or city in a graph. |
| Inferential Statistics | To predict if people without a primary care provider were more likely to be hospitalized after visiting the emergency room. |
Sample Exercise 18.1
Identify if the following situation uses descriptive or inferenti