Searching for the best evidence. Part 2: searching CINAHL and Medline
- Health Information Research Unit McMaster University Hamilton, Ontario, Canada
The first part of this editorial (July issue) described the information resources that nurses need to support their practices and other activities. This editorial will focus on 1 type of information resource—large bibliographic databases—and will describe how to harness the full potential of 2 databases (CINAHL and Medline) to identify studies that report high quality research that is ready for clinical application.
Proverbially speaking, looking for studies that are ready for clinical application is like looking for a needle in a haystack. The healthcare literature contains an abundance of research reports and studies that are in the early stages of development but few studies that are appropriate for clinical application. One estimate is that for every 5000 ideas that are initially postulated as improvements in health care, only 1 is fully evaluated and proved to be effective for changing healthcare practice.1 This makes effective and efficient searching of the literature even more critical.
Fortunately, articles reporting findings that are ready for clinical application can be retrieved using search strategies based on the principle of searching for studies which use the right method to answer their research question. We will briefly describe the research methodologies used in high quality studies on treatment (interventions), diagnosis (screening and assessment), prognosis, causation, as well as systematic reviews and qualitative studies as described in the purpose and procedure section, and relate these to terms and phrases that can be applied for searching CINAHL and Medline. The methodologies described in articles that are ready for clinical application are unique and separate these articles from news reports, idea papers, laboratory and animal studies, early human research, and clinical research that does not use the most appropriate methodology for the question. The table summarises search terms that can be used to retrieve primary (ie, original) studies and …