This article continues the Journal's series on implementing the Evidence-Based Dentistry (EBD) process into clinical practice. The abundance of scientific literature can make finding the best evidence to answer a clinical question challenging. This article presents strategies for critically appraising literature to ensure the validity and reliability of its conclusions.Implementing evidence-based dentistry requires the adept integration of current evidence into clinical practice. A robust evidence-based approach hinges on the provider's competence in identifying and effectively applying evidence to practice. This entails addressing three key questions: 1) Are the results valid? 2) What are the results? and 3) Can the evidence be applied to my patient? This article guides the reader through addressing the first question: Are the results valid? Determining how evidence can be applied to clinical decision-making presents challenges in understanding a study's strengths and weaknesses. This initial, often overlooked step is critical as a study's quality must be comprehended before assessing its results—an essential practice due to the adage "garbage in, garbage out." Assessing the validity of evidence involves evaluating potential biases, most commonly selection bias, performance bias, detection bias, attrition bias, reporting bias, and confounding. Critical appraisal, a key component of evidence evaluation, involves evaluating the strengths and weaknesses of a study to determine if the evidence is reliable enough to guide practice. Various biases inherent in scientific studies underscore the importance of critical appraisal. A systematic understanding of study designs—observational (cohort, case-control, cross-sectional) and experimental (randomized controlled trial)—is essential for accurately assessing evidence. Types of biases inherent in scientific studies necessitate understanding their impact on evidence quality. These include selection bias, performance bias, detection bias, attrition bias, reporting bias, and confounding. Each bias distorts the interpretation of results, underscoring the importance of critical appraisal. Understanding primary evidence from individual studies is crucial, but synthesizing evidence through secondary sources like systematic reviews enhances the process. Systematic reviews amalgamate findings from multiple studies to draw meaningful conclusions, typically followed by meta-analyses that quantify collective outcomes. To foster the acquisition of critical appraisal skills, practitioners can employ various tools as guides, each tailored to specific study designs. These tools elucidate critical questions to evaluate potential biases and methodological aspects of studies. As critical appraisal becomes habitual, clinicians delve into the often-overlooked methods section of scientific articles, leading to comprehensive assessments of study validity. Ultimately, engaging in critical appraisal empowers clinicians to discern reliable evidence, paving the way for effective evidence-based clinical decision-making.
Frantsve-Hawley, Julie PhD
"The Skill of Critical Appraisal: Determining if the Results Are Valid,"
The Journal of the Michigan Dental Association: Vol. 102:
4, Article 4.
Available at: https://commons.ada.org/journalmichigandentalassociation/vol102/iss4/4