Searching for the best evidence. Part 1: where to look
- Health Information Research Unit, McMaster University, Hamilton, Ontario, Canada
Clinicians are continually challenged to keep up with the rapidly growing and changing information base relevant to their areas of practice. They must not only locate relevant information but must also assess its quality, asking themselves do I, or should I, believe this information? Increasingly, they must deal with conflicting information. For example, 1 study may report that treatment A was better than treatment B, but another study may report just the opposite. This is the first of 2 editorials on searching for the best evidence. It will describe the 5 main types of information sources that can be used to meet the information needs of nurses, with examples of the types of sources that are best suited to addressing different kinds of questions. Part 2 of this editorial will focus on techniques for the efficient retrieval of high quality information from an important information source for nurses—that is, electronic bibliographic databases, specifically CINAHL and Medline.
For nurses, most information needs can be met using 5 types of sources: textbooks, journals, online bibliographic databases, products that distill or consolidate research, and the internet. Each will be discussed in turn below.
Textbooks provide information for 2 types of needs. Whether the texts are traditional or on CD ROM disks, books are invaluable for addressing specific “stable” information needs—that is, facts that do not often change such as gross anatomy, basic principles and mechanisms, and specific disease characteristics. If they are up to date, texts can also provide summaries of new or complex topics, or put an issue in the context of other related areas of knowledge. Examples of the type of questions that can be answered using textbooks are: what are the developmental milestones for 2 year old children? and what is the incubation period for chickenpox?
Many health professionals feel …