Levels of Evidence Instructions

One of the first steps in research of evidence-based practice in healthcare is to do a review of literature on a topic of interest, as you did in Module/Week 2 with your Literature Review of the Clinical Guideline you chose.

One of the next steps in research is to identify how reliable each of those four articles are. You will do this by identifying the level of evidence in each of the four articles you used in week 2.

  • Review the four articles you gathered for your Literature Review (Module/Week 2) and identify the hierarchy/level of evidence provided for each article chosen from Level I to Level VII.
  • In addition to the identification, explain the criteria that caused you to choose that level of evidence.
  • Include a biblical integration or Christian worldview for each (different than the ones used in the Literature Review, since this is a different assignment).
  • Make sure to follow current APA format for your references and in-text citations.
  • Use the template provided.

Levels of Evidence

Rating System for the Levels of Evidence (LOE): https://libguides.winona.edu/c.php?g=11614&p=61584

Here are the levels of evidence (from the highest, most reliable strength of evidence to the lowest) defined more thoroughly:

Level I:

  • Evidence from a systematic review (literature review of articles) of all relevant randomized controlled trials (RCTs) or at least three RCTs that have similar results
  • A meta-analysis study
  • An evidence-based clinical practice guideline based on systematic reviews (literature review of articles) of RCTs

Level II:

  • Evidence obtained from at least one well-designed Randomized Controlled Trial (RCT)

Level III:

  • Evidence obtained from well-designed controlled trials without randomization
  • A quasi-experimental design: Not true experiment designs. Descriptive research involves collecting data to test hypotheses or answer questions concerning the current status of the subjects of the study. Describes the variables. Lacks the element of random assignment. Usually assigned to 2 groups without randomization, or using a comparison group instead of a control group. Quasi-experimental research involves the manipulation of an independent variable without the random assignment of participants to conditions or orders of conditions. Among the important types are nonequivalent groups designs, pretest-posttest, and interrupted time-series designs.

Level IV:

  • Evidence from well-designed cross-sectional study
  • A case-control study (not the same as a case study) or retrospective studies in which people who have a specific condition or outcome are compared with people who do not. Researchers are retrospectively relying on patient recall or medical records for their data collection.
  • A cohort study, an observational study type that prospectively follows a large group of patients with a specific exposure or treatment and then compares outcomes with an unaffected group. Cohort studies are observational. Longitudinal designs fall here, too.

Level V:

  • Evidence from systematic reviews (literature review of articles) of descriptive studies and/or qualitative studies
  • A meta-synthesis study
  • Meta-aggregation is an approach that is increasing in popularity as a method of qualitative synthesis designed to model the Cochrane process of systematic reviews summarizing results of quantitative studies while being sensitive to the nature of qualitative research and its traditions

Level VI:

  • Evidence from a single descriptive study
  • Evidence from a single qualitative study: Like interviews without intervention or focus groups. They provide rich data on the views or experiences of one person or more. Can provide insights in unexplored contexts.

Level VII:

  • Evidence from the opinion of authorities and/or reports of expert committees

Here are some areas of the textbook to review for further explanation of the terms used above. The page numbers below refer to pages in chapters in the textbook, Evidence-based practice: An integrative approach to research, administration, and practice (2nd ed.) from Editors Heather R. Hall and Linda A. Roussel (2017). The terms are in alphabetical order:

Some Definitions from the textbook:

  • Case-Control Studies: pp. 30, 37-38
  • Cohort Studies: p. 291
  • Cross-Sectional Study: p. 25 Observing a population at one specific point in time
  • Descriptive Study: Observing and describing behavior without influencing it
  • Evidence-Based Clinical Practice Guidelines: pp. 312-313
  • Expert Committees: p. 291
  • Focus Groups: pp. 25, 28, 29, 68, 71, 71
  • Levels of Evidence: pp. 290-295
  • Longitudinal Design: p. 25 Observing something that happens to a population (the same people) at different points in time (falls under cohort study)
  • Meta-Analyses: pp. 20, 290-291, 296
  • Meta-Synthesis: p. 40
  • PICOT: pp. 249, 288-290
  • Quasi-Experimental: pp. 9, 12-13, 72
  • Randomized Control Trials (RCT): pp. 15, 70, 284, 290-291
  • Research Design: pp. 8-22
  • Single Descriptive or Qualitative Studies: p. 291
  • Systematic Review: pp. 19, 129-133, 290-291, 293-294, 296