11.3: Evaluating the Quality of the Evidence
By the end of this section, you should be able to:
- Demonstrate an understanding of the different levels of evidence.
- Describe how to evaluate a research study.
In the process of EBP and EBDM, nurses and other health care providers need to understand how to evaluate the quality of evidence. Furthermore, they need to understand why this evaluation should take place. Taking the necessary steps to evaluate the quality of each piece of evidence ensures that each adds value to the project and helps meet the user’s needs and expectations. This process may also help identify gaps in what has previously been researched and/or implemented.
Levels of Evidence
Once evidence has been collected from the literature, the information must then be organized and categorized. To help determine the best and most accurate information available, Johns Hopkins University created the Nursing Evidence-Based Practice (JHNEBP) Model, which utilizes a three-step process for a problem-solving approach to decision-making in clinical practice (Johns Hopkins Hospital, 2017; Johns Hopkins University & Medicine, 2020). Information regarding the JHNEBP Model can be reviewed at the Johns Hopkins website.
This video discusses the JHNEBP Model.
Watch the video, and then respond to the following questions.
- What are two goals of this model, and why are they important for implementation?
- Discuss the three-phase process used in this model.
(See Henry, 2022.)
Utah State University Library has created a video to help explain EBP and how it can be used in nursing and medical practice.
Watch the video, and then respond to the following questions.
- What are the three main elements of evidence-based practice?
- Why are a client’s values and preferences a component of evidence-based practice?
Evaluating the Evidence
After understanding the levels of evidence available during the literature review, the next step is to appraise the evidence. The three main steps in evidence appraisal are identifying the type of evidence, determining the evidence level and strength, and then evaluating the quality of the evidence.
Evidence appraisal entails reviewing acquired information and systematically assessing its intended audience, purpose, relevance, applicability, validity, and reliability. The intended audience is the demographic that the writer or writers expect to read and interact with the information. The purpose of an article, often presented in a purpose statement early in the article, identifies the reason for the project or study. An article’s statement of purpose can help a nurse to quickly identify whether the article will help answer the research question. Furthermore, the article should be reviewed for relevance , meaning how closely the source’s elements relate to the research question and whether the results can be applied to the intended population. Applicability , or how well the results and data pertain to a broad or specific population, is an important piece of appraisal. Validity refers to the degree to which the information within the article is factual. This is sometimes referred to as accuracy or credibility in research articles. Correspondingly, reliability is the extent to which results can be reproduced if research is completed under the same conditions. Figure 11.3 demonstrates the search pyramid tools researchers use to rank the evidence they gather. Each level of evidence pulls from the research obtained at lower levels, meaning the highest and most synthesized information is at the top of the pyramid. The highest quality, most reliable evidence from the highest level of the decision pyramid is most likely to support effective action and should be used first.
Read the scenario, and then answer the questions that follow based on all the case information provided in the chapter thus far. This case study is a follow-up to Case Study Part B.
Using research databases, Amari and Milo found four quantitative studies and three qualitative studies regarding exercise and mental health. Additionally, they surveyed the community to identify components of community exercise programs. This survey included physical locations, cost, and general attendance of these classes and programs. They also spoke with the local school systems to determine how physical education is incorporated into the high school curriculum. Amari and Milo must now appraise the evidence in order to select which data points to use and to what degree.
5. Which factor should Amari and Milo consider in their appraisal of the evidence they found?
- The reputation of the researcher
- The cost of the study
- The length of the study
- The trustworthiness of the study
6. During their appraisal of the evidence, which type of study would provide Amari and Milo with the highest quality of evidence?
- Randomized controlled studies
- Anecdotal reports
- Cross-sectional studies
- Summaries
This PBS video outlines gaps in representation of racial and ethnic groups in clinical trials and medical research. These gaps limit the amount of information available about diverse populations, which can skew perspectives on care. Nurses in public health must find ways to combat these gaps.
Watch the video, and then respond to the following questions.
- How can public health nurses help mitigate the discrepancies in representation currently seen in medical trials and research?
- Reverend Alvin Hathaway states, “That’s not really bias, that’s just accessibility” when discussing funding slanted toward a European data set. What does this mean? How can public health nurses help to broaden this data set?
Each article or source identified in the literature review of a project should be appraised considering the aspects discussed above. The Johns Hopkins Toolkit provides a guide to evidence level and quality, which can facilitate this process. Once this appraisal has been completed, the sources can be categorized and ranked to determine which ones may be helpful to use as a foundation for the research ahead. Nurses should use this process to identify strong research that can support the outcomes of their EBP intervention.
Read the scenario, and then respond to the questions that follow.
Throughout this chapter, Amari and Milo have applied the EBDM process to a concern in their community. This segment reveals the outcome of their process. Read the scenario, and then respond to the following questions.
After synthesizing the data, Amari and Milo note that consistent interventions discussed to support mental health in adolescents are regular exercise, appropriate sleep, and relaxation techniques. Specifically, the literature supports structured exercise classes and group movement as a successful method to reduce adolescent anxiety.
While the research supports specific interventions, as public health nurses, Amari and Milo know they need to also take into consideration the NCCMT Model for evidence-based decision-making as it incorporates research, community health issues in the local context, community and political preferences and actions, public health resources, and public health expertise. With that, their assessment notes the limited access to workout facilities such as public gyms for many of the adolescents in the community. Additionally, they note a high price for membership compared to the average family income. They are also aware that many adolescents in the community work to help support themselves and their families. This not only limits their time availability but also speaks to the additional monetary strain. After speaking with a representative of the public school system, they note that physical education classes are optional for high school juniors and seniors. They find many students opt out of this class as their other option is early release or study hall.
Due to all these factors, the nurses identify that although the literature is clear on a specific intervention for exercise, it may not be the best option for their current community. Instead, the two decide they can still implement interventions for daily exercise that consider these community factors.
This leads them to the adapt phase. They decide to implement the following interventions:
Offer free daily classes at the community health center lead by volunteers. These classes will be offered at two different times each day and will be available to all adolescents within the community.
Compile a list of free exercise resources on the health department website that adolescents can use directly by streaming them at home, if possible, or in the community center with free internet. Additionally, Amari and Milo have worked with the high school and obtained support for two computers to be used for this resource that will be available for students during their study hall.
Each participant who attends a class will sign in to track use of this resource. Those who access the electronic resources will have a unique log-in passcode. These will be used to track the amount of exercise over 3 months for each participant. This data will then be looked at in comparison to the level of anxiety reported by adolescents in the community.
After three months of implementation, Amari and Milo review the rates of exercise and rates of anxiety for adolescents in the community. They find a decrease in anxiety for those who participated in exercise at least 5 times a week. Due to these results, the nurses begin brainstorming how they can expand these interventions. They will support daily exercise but note that activity at least 5 days a week helps reduce anxiety. They plan to obtain data for three more months and then disseminate their results at that time.
- Identify and discuss the last step in the public health decision-making process. What takes place during this step, and why is it important?
- Do you agree with the implemented interventions? Why or why not?
- What other interventions would you propose? How would you ensure your recommendations are evidence-based? Provide at least two alternative interventions with resources cited for support.