Bradley University's graduate nursing programs use the Johns Hopkins Evidence-Based Practice for Nurses and Healthcare Professionals Model. This model includes tools for determining the level of evidence of a source.
Critical appraisal is the process of careful & systematic examination of research to judge its trustworthiness, validity, reliability, value, & relevance to a particular context. Use the Johns Hopkins EBP Evidence Appraisal Tool for Research [Appendix E] or Nonresearch [Appendix F]) to determine quality ratings.
The level of evidence, often depicted as an EBP pyramid, is determined by the methodology of the study. Level I evidence is the highest level of evidence. Use the Johns Hopkins EBP Hierarchy of Evidence Guide [Appendix D] to determine the level of evidence for a study.
Johns Hopkins Evidence-Based Practice for Nurses and Healthcare Professionals Model information and the tools for appraisal and level of evidence can be found in the guide and files linked below.
You may need to create an Evidence Evaluation Table (EET) as part of your research project. The EET table is a way to organize the sources you will include in your project/assignment and also critically evaluate them.
Research studies tend to follow the same IMRaD format (Introduction, Methods, Results, Discussion, Conclusion) so you can locate the elements you need for the EET table in the same section in each source.
| Element from EET | What it means | Where to find this information in the source |
| Study/Source | APA Reference (for use in reference lists) |
-first page -record in the database |
| Purpose of Study | Why study was done (as stated by authors) |
-Introduction -look for "We + verb", for example, we studied, we investigated, we applied... |
| Design/Method | How was study carried out? | -Methods |
| Sample Setting | Number & characteristics of participants; attrition rate & why | -Methods |
| Measurement Tools | Name & author of scale(s) used to measure outcome variables (If another's tool is used) | -Methods |
| Data Analysis | Statistics (that were used to answer clinical question) | -Results |
| Findings | What were the results? (Statistical or qualitative findings) | -Results |
| Major Variables | List the independent & dependent variables(IV & DV) |
-Methods -possibly Results/Discussion |
| Level of Evidence | Study’s type and level of evidence *refer to LOE pyramid | -Methods |
| Appraisal: Impact on Practice Conclusion(s) | Strengths, weaknesses, limitations; feasibility of use in practice. | -Discussion/Conclusion |
| Usefulness to answering the PICO | Supportive, Nonsupportive, Inconclusive |
You will need to be familiar with research terms in able to complete the EET.
You will need to know research terms like
You will also need to know study designs, such as
The Centre for Evidence-Based Medicine's Study Design webpage is very helpful for determining the study design.
Grimes and Schulz (2002) created a decision tree diagram to help with determining the study design. This article is accessible through the library's database subscriptions. Use the link in the citation below to access it.
Grimes, & Schulz, K. F. (2002). An overview of clinical research: the lay of the land. The Lancet., 359(9300), 57–61.
You can also use the glossaries below to (re)familiarize yourself with research terms and concepts.
Tip: The independent variable is the intervention. The dependent variable is the outcome.