Learn how to appraise the literature
(Evaluating the evidence)
APPRAISING Scientific Literature
After scouring the databases for studies that represent the highest level of evidence for your clinical question, it is time to evaluate the articles you have found. It is not enough to just read the articles on your given topic. You need to understand the strengths and weaknesses of each study before deciding whether to apply its recommendations to your clinical practice.
While reading any scientific study, these are the three question you will want to ask yourself:
How To Read A Research Article
Reading a research paper requires a different skill set than reading a novel or a newspaper article.
Research papers are organized into distinct sections, and knowing which sections will provide you with the information you need to determine the results, relevancy, and validity will save you time and energy.
Below are some short, simple videos that explain the how to efficiently read scientific articles.
Articles on Reading and understanding Research
Books on Appraising REsearch Studies
The library has access to several eBooks on evidence-based practice that have chapters on appraisal. To access these titles off-campus, please contact the librarian for login credentials.
Are the Results Valid?
Validity is a measure of how sound a research study is. Does the study do what the researchers claim it does? There are two types of validity that you should look at when appraising the validity of a study- internal and external.
Articles on Validity
Here are some articles that can further explain how to assess the internal and external validity of a research article.
Videos on Validity
Below are a number of videos that explain internal and external validity that may help with your understanding of these concepts.
What are the Results?
There are two main questions you will want to considering when evaluating what the results of a study are:
1. What are the overall results?
2. How precise are the results?
When trying to determine the overall results, you should be looking for the "Results" or "Findings" section of the article. The results may be presented in numerical format. When looking at this section, try to determine if the results are clear to you. Did the authors find a difference between the control group and the experimental group? And if the authors did find a difference, how large was the confidence interval? A smaller confidence interval indicates a more precise result.
Below are a number of resources that can help you understand the statistical terminology you will encounter while reading research papers.
Understanding the results Videos
Articles on understanding Statistics in nursing Research studies
Here are some journal articles that provide some guidance on understanding statistics in nursing research that will be helpful in your appraisal of the evidence:
Books on Statistics in Nursing Research
Here are several textbooks you can refer to if you'd like more in-depth information on statistics in research.
aRE THE RESULTS rELEVANT TO MY cLINICAL qUESTION?
After you understand the results of the study, and have determined that the study is valid, you must then determine whether the results are relevant to your clinical question and your local population.
The questions you will want to ask yourself are*:
*Adapted from the Critical Appraisal Skills Programme (CASP) Randomised Controlled Trials Checklist
CASP Critical Appraisal Checklists
The Critical Appraisal Skills Programme out of Oxford, UK has developed a number of easy-to-use checklists to promote the practice of evidence-based medicine by helping health care staff make sense of scientific literature. These are free to download and use under the Creative Commons License. You can use these to evaluate articles the articles you found in the ACQUIRE step.
Other Appraisal Resources
AJN's Critical Appraisal of the Evidence Series
In 2010, the American Journal of Nursing published a series of articles on EBP. Three of these articles focused on the critical appraisal of nursing literature. Below are full-text links for this series.
Curriculum Renewal for Evidence based medicine
Below are a series of videos produced by Monash University and funded by the Australian Government Office for Learning and Teaching which give a more in-depth look at appraising different types of medical studies.