Can You Touch Your Toes?Using Tables of Evidence (TOES) to Organize Your Evidence Review

Abstract

When working with students or practicing nurses who want to engage in evidence-based practice (EBP), the usual first directive is to construct a problem, intervention, comparison, and outcome (PICO) question and then search the literature to find evidence to answer that question. Usually, what happens next is that students and clinicians alike amass a stack of research articles which may or may not be related to their topic. Despite the admonition of faculty and mentors to use a systematic search process, students fall back to old habits.Typically, much of the literature they accumulate does not relate directly to the PICO question. At this junction, it is imperative for the faculty member or mentor to help students differentiate the apples from the oranges (Levin, 2006). A successful teaching strategy to do this is to ask students to first provide you with abstracts of the studies they have retrieved before requesting the full text. That way, you are able to make sure that there are only apples in the literature basket.The next step in the EBP process is for the students or clinicians to read, appraise, and synthesize the evidence that they have gathered to determine if the extant evidence provides answers to their clinical question. Many students and clinicians alike initially are overwhelmed by the accumulated evidence: The reading is manageable, the appraisal is challenging, but the synthesis seems nearly impossible. They find that although they have read the articles and can discuss individual studies, they are unsure of how to integrate them in a way that answers their question. This is because a linear review of the evidence can lead to inefficiency in creating a clear picture of the available science on a particular topic. To help students and clinicians to streamline the literature review and synthesis process, the use of a table of evidence (TOE; also called a literature review matrix), which organizes the details of the research gathered in relation to a PICO question, is a helpful and necessary tool.WHAT IS A TABLE OF EVIDENCE?A TOE is essentially a table with rows and columns populated with focused aspects of each article included in the evidence review. The rows hold the specifics of the individual studies. The important elements to be taken from each article are identified by the headings of the columns. The cells of the table are filled in with the information listed at the top of the column (Worral, Levin, & Arsenault, 2010). The individual or individuals conducting the evidence review decide upon what the column headings should be, and then information from each article is pulled out and included in the table for the purposes of the review. This process is called abstracting (Garrard, 2011). An example of a TOE can be seen in Table 1. The TOE can be constructed any way the reviewers desire. It is a dynamic tool; columns may be added or changed at any time depending on the shifting focus of the PICO question or what is trending in the literature (Garrard, 2011). Although the TOE is most useful for research studies, it can include nonresearch articles as well.BENEFITS OF USING A TOEAt first, some believe that creating a TOE is cumbersome and creates more work. This is untrue. A benefit of using a TOE is that it is easy to set up in any word processing program and allows the user to get started immediately. …