Clinical Inquiry and Evidence-Based Practice
6
Evidence Levels
Systematic reviews down to expert opinion
4
PDSA Steps
Plan Do Study Act
1
Top Level
Systematic reviews and meta-analyses
Levels of Evidence
not all evidence is created equalSystematic reviews and meta-analyses of RCTs
Randomized controlled trials (RCTs)
Controlled trials without randomization
Cohort and case-control studies
Descriptive and qualitative studies
Expert opinion and committee reports
Systematic reviews and meta-analyses sit at the top of the evidence pyramid. Expert opinion sits at the bottom.
Quality Improvement Methodologies
PDSA (Plan-Do-Study-Act) is the most commonly tested QI cycle
Lean methodology eliminates waste in processes
Six Sigma reduces variation and defects
Root cause analysis (RCA) for sentinel events
Nurse's role includes identifying practice questions and participating in EBP projects
AACN practice alerts provide evidence-based recommendations for bedside care
Key Values to Memorize
Level I = systematic review
Level VI = expert opinion
PDSA = iterative cycle
EBP = evidence + expertise
AACN practice alerts
RCA for sentinel events
EBP questions are free points when you know the pyramid
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Practice CCRN QuestionsExam Traps
Systematic reviews outrank expert opinion
The evidence pyramid places systematic reviews and meta-analyses at the top and expert opinion at the bottom. A single expert saying "this is how we have always done it" carries far less weight than a systematic review of multiple randomized controlled trials. The exam tests this hierarchy.
PDSA cycle is iterative
Plan-Do-Study-Act is not a one-time process. You plan a change, implement it on a small scale, study the results, and act on what you learned. Then you repeat. Each cycle refines the intervention. The exam may present scenarios where the PDSA cycle needs to be repeated.
EBP is not just reading research, it is applying it
Evidence-based practice means integrating the best available evidence with clinical expertise and patient preferences. Reading a study is not EBP. Changing your bedside practice based on appraised evidence is EBP. The exam distinguishes between knowledge and application.
AACN practice alerts are evidence summaries
AACN practice alerts synthesize the best available evidence into actionable recommendations for critical care nurses. They cover topics like alarm management, oral care, progressive mobility, and family presence. Know that these exist as a resource.
Evidence Hierarchy
Systematic review > RCT > cohort > case study > expert opinion. "We have always done it this way" is the weakest possible evidence.
PDSA Is Iterative
Plan a small change. Do it. Study the outcome. Act on what you learned. Repeat. Each cycle improves the intervention. Never just one pass.
You notice your grandma's soup recipe calls for a step that seems unnecessary. Is it really needed? That question, "does this step actually make a difference," is clinical inquiry. In nursing, it sounds like "is this intervention actually improving outcomes for our patients?"
Instead of just asking grandma (expert opinion), you search for taste tests (research studies) that compared soup with and without that step. A single taste test is a case study. Multiple taste tests compiled together is a systematic review. The more rigorous the testing, the more you trust the result.
PDSA is your own kitchen test. You make a small batch without the step (Plan + Do), taste the result (Study), and decide whether to keep the change (Act). If the soup is better, you make it the new recipe. If not, you try a different modification. Each cycle gets you closer to the best soup.
When the evidence is strong enough to change practice, the new approach becomes the standard. AACN practice alerts are like updated cookbook entries that reflect the latest kitchen science. Evidence over tradition, always.
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