Clinical Nurse Leader Practice Exam

Which type of evidence is preferred for evaluating an evidence-based intervention?

1. Meta-analysis

2. Quasi-experimental

3. Experimental

4. Qualitative

The correct answer is: Experimental

The preference for experimental evidence in evaluating an evidence-based intervention stems from its robust design that allows for stronger causal inferences. In experimental research, such as randomized controlled trials, participants are randomly assigned to either the intervention or control group. This randomization minimizes bias and confounding variables, ensuring that any observed effects can be more reliably attributed to the intervention itself rather than external factors. Experimental studies provide the highest level of evidence due to their systematic approach in measuring outcomes and controlling for variables. They typically yield more reliable data that can be generalized to a broader population, which is crucial for informing clinical practices. While meta-analysis, quasi-experimental, and qualitative research all provide valuable insights, they do not match the level of certainty regarding causation and direct effects that well-conducted experimental studies do. Meta-analysis aggregates findings from multiple studies but relies on the quality of those studies, which might include lower-tier evidence. Quasi-experimental designs lack random assignment, which can introduce bias. Qualitative studies are primarily exploratory and can provide rich context but do not measure the effectiveness of interventions in a quantifiable manner. Thus, experimental evidence is considered the gold standard for evaluating the efficacy of evidence-based interventions.