Evidence-Based Nursing is, “an ongoing process by which evidence, nursing theory and the practitioners’ clinical expertise are critically evaluated and considered, in conjunction with patient involvement, to provide delivery of optimum nursing care for the individual” .
EBN is an approach to practice that is intended to improve the safety and effectiveness of nursing care and practices.
Evidence-based practice consists of five steps:
ASSESS the patient
ASK a searchable clinical question
ACQUIRE the best evidence to answer the question
APPRAISE the evidence
APPLY to the patient
Also consider the type of question you are asking and determine what study type might be most relevant.
Most Clinical Questions: Meta-Analyses, systematic reviews
Therapy: Randomized Controlled Trial
Diagnosis: Prospective, blind controlled trial compared to gold standard
Prognosis: Cohort study, case control, case series/case report
Recommended list of Nursing Journals to support nursing students in developing the knowledge and skills they need to implement EBP consistently, one step at a time.
American Journal of Nursing
American Nurse Today
Nursing Made Incredibly Easy
Some other U.S. Nursing Journals which often have articles written by nurses in the field of medicine:
Journal for Nurse Practitioners
Critical Care Nursing Clinics of North America
Nursing Clinics of North America
The most important step in Evidence-Based Nursing (EBN) is to correctly identify a problem through patient assessment or practice assessment, processes that require reflection by the nurse on clinical practice, in conjunction with a knowledge of the patient's present circumstances. The information below describes how to frame the question once the patient or practice assessment and the resulting problem identification have occurred.
Background questions ask for general knowledge and do not normally arise from the need to make a clinical decision.
Foreground questions ask for specific knowledge to inform clinical decisions or actions.
Clinical questions typically fall into one of four main categories:
* Knowing the type of clinical question is important later in the EBN process--once the nurse goes to look for studies that will answer his/her question.
Nursing Practice Questions
In nursing, many other questions about practice will also arise, with some of the questions resulting from the nursing principle of working with rather than on the patient. These questions can be quantitative or qualitative in nature. Examples include:
Clinical and nursing practice questions can be broken down into the PICO(T) format, which breaks a question apart into searchable parts:
P – Patient, population, problem
I – Intervention or Exposure
C – Comparison
O – Outcome
T – Time (optional)
Example: A small, rural hospital's primary population has become elderly patients and the nurses are working together to update patient safety procedures. When they look at hospital records, they realize that falls are their number one risk factor among their patients. The question might be: what is the effectiveness of restraints in reducing the occurrence of falls in patients 65 and over? , which can be broken apart into descriptors, written in noun forms, such as:
A worksheet to assist you in breaking your question apart using PICO can be found here:
The following examples may help you put PICO into practice. Suggestions in the brackets are just extra ideas for what you might want to consider.
1) Isobel is a 45 year old woman who asks you for advice on natural ways of resolving her depression. She's particularly interested in whether she'd gain any benefits to her mental health from exercising.
P - 40 plus year old woman with depression (but also ask whether you need to know the severity of her depression, and whether she has any other health conditions that may suffer or benefit from exercise)
I - Exercise (but what type and how strenuous?)
C - Antidepressants (what strength and for how long?)
O - Reduced or eradicated depression.
So your question might be:
2) Fred is 72, and is undertaking therapy for recovery from a stroke which affected his mobility. His daughter is a strong advocate of acupuncture, and has suggested he ask about it at his next appointment with you.
P - Men in their 70s who have suffered from stroke
I - Acupuncture (but duration, frequency etc?)
C - Fred's current therapy
O - Higher recovery rate (in terms of time of recovery and level of improvement to mobility)
So your question could be:
Your questions might not match these exactly, but they should contain all the elements from your PICO answers, and your choice of comparison and outcome will modify your question somewhat. For example, you might modify your question to include specific brands/types of therapy such as light jogging versus a specific drug in the depression scenario.
Once you've attributed each element of your scenario to PICO, you can then start to look at formulating a list of synonyms to use in searching.
Using the depression and exercise example above, we could look at it like this (we are sure you can think of many more alternative terms though!):
|PICO answer||Synonym 1||Synonym 2|
|40 year old woman||middle aged woman||middle aged female|
|Exercise||physical therapy||physical exertion|
|Antidepressants||[name of antidepressant]||medication|
|Reduced depression||treatment of depression||management of depression|
Levels of evidence are assigned to studies based on the methodological quality of their design, validity, and applicability to patient care. The combination of these attributes gives the level of evidence for a study. In nursing, the system for assigning levels of evidence is often from Melnyk & Fineout-Overholt's 2011 book, Evidence-based Practice in Nursing and Healthcare: A Guide to Best Practice. The Levels of Evidence below are adapted from Melnyk & Fineout-Overholt's (2011) model.
About Levels of Evidence and the Hierarchy of Evidence: While Levels of Evidence correlate roughly with the hierarchy of evidence (discussed elsewhere on this page), levels of evidence don't always match the categories from the Hierarchy of Evidence, reflecting the fact that study design alone doesn't guarantee good evidence.
About Levels of Evidence and Strength of Recommendation: The fact that a study is located lower on the Hierarchy of Evidence does not necessarily mean that the strength of recommendation made from that and other studies is low--if evidence is consistent across studies on a topic and/or very compelling, strong recommendations can be made from evidence found in studies with lower levels of evidence, and study types located at the bottom of the Hierarchy of Evidence. In other words, strong recommendations can be made from lower levels of evidence.
For example: a case series observed in 1961 in which two physicians who noted a high incidence (approximately 20%) of children born with birth defects to mothers taking thalidomide resulted in very strong recommendations against the prescription and eventually, manufacture and marketing of thalidomide. In other words, as a result of the case series, a strong recommendation was made from a study that was in one of the lowest positions on the hierarchy of evidence.
Quantitative Evidence Pyramid
Qualitative Evidence Pyramid
It is common to confuse systematic and literature reviews as both are used to provide a summary of the existent literature or research on a specific topic. Even with this common ground, both types vary significantly. Please review the following chart (and its corresponding poster linked below) for the detailed explanation of each as well as the differences between each type of review.
|Systematic Review||Literature Review|
|Definition||High-level overview of primary research on a focused question that identifies, selects, synthesizes, and appraises all high quality research evidence relevant to that question||Qualitatively summarizes evidence on a topic using informal or subjective methods to collect and interpret studies|
|Goals||Answers a focused clinical question
|Provide summary or overview of topic|
|Question||Clearly defined and answerable clinical question
Recommend using PICO as a guide
|Can be a general topic or a specific question|
|Components||Pre-specified eligibility criteria
Systematic search strategy
Assessment of the validity of findings
Interpretation and presentation of results
|Number of Authors||Three or more||One or more|
|Timeline||Months to years
Average eighteen months
|Weeks to months|
|Requirement||Thorough knowledge of topic
Perform searches of all relevant databases
Statistical analysis resources (for meta-analysis)
Understanding of topic
|Value||Connects practicing clinicians to high quality evidence
Supports evidence-based practice
|Provides summary of literature on the topic|
Why Do I Need Journals and Databases?
As professionals you will want to use bibliographic databases such as CINAHL and PubMed (MEDLINE) to keep current with the research literature. In addition, full text databases such as the Cochrane Library (a database of systematic reviews), textbook resources such as STAT!Ref, and electronic journals such as Evidence Based Nursing can provide needed information, quickly and easily.
How the Library Can Help
While some web-based resources are free, many quality resources, such as the indexes, databases, journals, and textbooks that you need to do your job have a cost associated with them. Libraries provide access to many online resources, by paying subscription fees to publishers and vendors with the understanding that their library users can access this information from within the library, on campus, and sometimes from off-campus computers as well through proxy access.
A bibliographic database leads the user to sources of information, usually in journals, providing a citation that includes the article's author, title and source information; journal name, volume, issue and page numbers, and often an abstract of the article. As opposed to the Cochrane systematic review databases, the searcher must analyze the quality and relevance of the studies themselves when using PubMed and CINAHL.
Here are the two of the most utilized databases by nurses:
The CINAHL database (Cumulative Index to Nursing and Allied Health) covers nursing, allied health, biomedical and consumer health journals, publications of the American Nursing Association, and the National League for Nursing. Over 350,000 records and 900 journals are included. It also includes healthcare books, nursing dissertations, standards of professional practice, nurse practice acts, and educational software.
PubMed (MEDLINE) is a free resource provided by the National Library of Medicine. Anyone can access this database, which is widely recognized as the premier source for bibliographic and abstract coverage of biomedical literature.
PubMed includes citation and abstract information from Index Medicus, Index to Dental Literature, and International Nursing Index, as well as other sources in the areas of allied health, physical therapy, health education, biological and physical sciences, humanities and information science as they relate to medicine and health care, communication disorders, population biology, and reproductive biology.