Evidence in the context of medical literature provides proof. It is created by experts or scholars in their area of research. The evidence produced in this research is transparent and reproducible.
"Evidence-based research is the use of prior research in a systematic and transparent way to inform a new study so that it is answering questions that matter in a valid, efficient, and accessible manner."
Robinson, K. A., Brunnhuber, K., Ciliska, D., Juhl, C. B., Christensen, R., & Lund, H. (2021). Evidence-Based Research Series-Paper 1: What Evidence-Based Research is and why is it important? Journal of Clinical Epidemiology, 129, 151–157. https://doi.org/10.1016/j.jclinepi.2020.07.020
Below is an edited version of the "Evidence Level & Quality Guide" of evidence-based medicine hierarchy from the Johns Hopkins Nursing Evidence Based Practice Model:
Level I | Experimental studies, systematic reviews of randomized controlled trials |
Level II | Quasi-experimental studies, mixed methods, systematic reviews of randomized controlled trials and quasi-experimental studies |
Level III |
Non-experimental studies, systematic reviews of randomized, quasi-, and non-experimental studies, mixed methods, qualitative meta-analysis |
Level IV | Expert opinions, clinical practice guidelines, position statements |
Level V | Traditional narrative literature reviews, quality improvement, case reports, opinions based on anecdotal evidence |
The steps of the ABCDE Framework (Price, 2020) will assist in the search for evidence.
A: Assess Topic, Scope & Goals
B: Brainstorm Keywords
C: Choose Databases & Resources to Search
D: Document the Search
E: Evaluate the Evidence
Price, C., Kudchadkar, S. R., Basyal, P. S., Nelliot, A., Smith, M., Friedman, M., & Needham, D. M. (2020). Librarian integration into health care conferences: a case report. Journal of the Medical Library Association : JMLA, 108(2), 278–285. https://doi.org/10.5195/jmla.2020.803
In this step, you will essentially be performing background research. The more you know about a topic, the easier it is frame your research question and perform the research.
1. Perform a general search. Still OneSearch on the library homepage provides access to a variety of databases which can assist with finding background information. (Still OneSearch video tutorial)
2. Gather search terms throughout your background research. What terms are other authors using to describe your topic?
3. Formulate a research question. PICO is the most common format (PICO tutorial).
4. Consult with your library liaison for assistance.
Generating a list of keywords or search terms helps to ensure that the vocabulary you will use in your search matches the vocabulary used by various authors and the controlled vocabularies of the databases used.
1. Keep a running list of synonyms or versions of how terms are spelled for each of your topic/PICO terms.
2. Review the list of "topic terms" or "keywords" listed in articles relevant to your topic.
3. Review the MeSH terms or controlled database vocabularies to locate synonyms or related terms.
4. Consult with your library liaison for assistance.
We have thus far defined evidence, formulated a research question, and developed a list of search terms.
Now to determine what type of evidence is needed, where to find the evidence and which databases to search.
1. Level 1 Evidence: Experimental studies, systematic reviews of randomized controlled trials will provide the strongest evidence.
2. PubMed is the best database to begin this search.
3. CINAHL Plus, Trip, and The Cochrane Library databases also provide Level I Evidence.
4. Consult with your library liaison for additional assistance
*Remember to access these databases through the ATSU library homepage for full access to their resources.
Quality of evidence is defined by it's ability to be transparent and reproducible. Documentation of your search strategies will ensure that the evidence you are providing in your research is transparent and reproducible and therefore give it strength. This process will also assist in the organization of your research processes.
1. Use a spreadsheet, Excel or Google Forms, to document databases searched, keywords/search terms, controlled vocabulary and limiters applied (date, article types, etc.)
2. Citation managers can also assist to organize your research findings.
3. Contact the library liaison for additional assistance
1. The first step in examining the evidence, once you have found the literature relevant to your topic of research, is learning how to read a research paper.
2. Critical Appraisal of the Evidence
3. Consult with your library liaison for additional assistance.