Key Questions in Appraising the Scientific Literature

The purpose of the third step in the evidence-based decision making (EBDM) process is to determine the validity and usefulness of the study, keeping in mind that scientific evidence is the product of well-designed and well-controlled research investigations and the hierarchy of evidence is based on the notion of causation and the need to control bias.⁹  Although each level of the hierarchy may contribute to the total body of knowledge, “ …not all levels are equally useful for making patient care decisions."¹⁰  As you progress up the pyramid, the number of studies and correspondingly, the amount of available literature decreases, while at the same time their relevance to answering clinical questions increases.

Conceptually there are three key questions that need to be asked:^4,5,11
(http://www.cche.net/usersguides; http://www.cebm.utoronto.ca/teach/materials/caworksheets.htm)

1. Are the results of the study valid?
2. What are the results?
3. Will the results help in caring for my patient?

A subset of more detailed questions exists for each of the three key questions.  These questions further help determine the validity, results, and applicability of the evidence.  In addition to the subset of questions, most of the checklists include helpful hints as to what the questions mean.  Table 1 provides an example of a Critical Appraisal Form and illustrates how it can be used to analyze a research article.

Click Here To Navigate Within Article >> Abstract Introduction Key Questions in Appraising the Scientific Literature Case Example Common Ways of Presenting Data Practice Tips Conclusions Appendix A: Glossary of Evidence-Based Terms References About the Authors
	Page 3 of 11
Citation Number: Vol. 4, No. 1, Page 044