A guide to critical appraisal of evidence

www.nursingcriticalcare.com TA M IS C IA O / S H U T T E R S T O C K Critical care nurses can best explain the reasoning for their clinical actions when they understand the worth of the research supporting their practices. In critical appraisal, clinicians assess the worth of research studies to clinical practice. Given that achieving improved patient outcomes is the reason patients enter the healthcare system, nurses must be confident their care techniques will reliably achieve best outcomes. Nurses must verify that the information supporting their clinical care is valid, reliable, and applicable. Validity of research refers to the quality of research methods used, or how good of a job researchers did conducting a study. Reliability of research means similar outcomes can be achieved when the care techniques of a study are replicated by clinicians. Applicability of research means it was conducted in a similar sample to the patients for whom the findings will be applied. These three criteria determine a study’s worth in clinical practice. Appraising the worth of research requires a standardized approach. This approach applies to both quantitative research (research that deals with counting things and comparing those counts) and qualitative research (research that describes experiences and perceptions). The word critique has a negative connotation. In the past, some clinicians were taught that studies with flaws should be discarded. Today, it is important to consider all valid and reliable research informative to what we understand as best practice. Therefore, the author developed the critical appraisal methodology that enables clinicians to determine quickly which evidence is worth Abstract: Critical appraisal is the assessment of research studies’ worth to clinical practice. Critical appraisal— the heart of evidence-based practice—involves four phases: rapid critical appraisal, evaluation, synthesis, and recommendation. This article reviews each phase and provides examples, tips, and caveats to help evidence appraisers successfully determine what is known about a clinical issue. Patient outcomes are improved when clinicians apply a body of evidence to daily practice.