Evaluating Evidence for Practice

Introduction 
Week 4: Appraising the Research: Part II
When a claim is made, such as "coffee causes cancer," data to support that claim play a critical role in determining the authority of such statements. The same holds true when examining issues in nursing practice. When analyzing evidence that addresses a nursing practice issue, nurses need to be able to interpret the findings of the statistical analysis of the study. In addition, how the statistical analysis was conducted needed to be assessed. Because sample sizes are often small and results may be different from sample to sample, nurses need to understand the statistical analysis well enough to be able to reliably draw conclusions from the data. This allows nurses to determine which claims are valid and which are invalid because of flawed research design, poor data collection methods, or faulty conclusions.
Statistical analysis is not just about mathematical calculations. Statistics also provide a way of organizing data, detecting patterns, interpreting findings, and validating an intervention. Learning to read and interpret the tables presenting the statistical analysis in a research study provides nurses with critical information.
This week you will investigate how to decipher statistical conclusions, analyze data, and interpret data tables. Following a brief review of basic statistics, this week will cover some commonly used statistical tests used in nursing research, as well as the difference between statistical significance and clinical significance.