Adult-Gerontology Clinical Nurse Specialist (CNS) Practice Exam

In evidence-based practice, which type of evidence typically ranks lowest?

1. Systematic review of high-quality, single-centered studies

2. Systematic review of high-quality, multi-centered studies

3. Expert opinion

4. Control studies

The correct answer is: Expert opinion

In evidence-based practice, expert opinion ranks the lowest in the hierarchy of evidence. This is because expert opinion is based on the personal insights, experiences, and interpretations of knowledgeable individuals in a field but lacks the rigor of systematic research methods. While such opinions can be valuable, they do not provide the level of reliability or generalizability that comes from more structured research, such as systematic reviews or controlled studies. Higher levels of evidence, such as systematic reviews of multi-centered studies or control studies, involve comprehensive analyses of multiple studies or well-designed randomized trials, which can demonstrate clear relationships and effects that are generalizable across different populations. These types of evidence have undergone peer review and often adhere to strict methodological standards, making them more trustworthy and influential in clinical guidelines and practice. Therefore, expert opinion is regarded as a lesser form of evidence in the context of decision-making in healthcare.