Evidence-Based Practice and Research Literacy
What evidence-based practice means
Evidence-based practice integrates the best available research evidence, practitioner expertise, and client values and preferences. It is not "using research only"; all three elements matter.
Core concepts
- Hierarchy of evidence: systematic reviews and randomised controlled trials generally sit above cohort, case-control, and expert opinion, though design must fit the question.
- Study designs: know the purpose of RCTs, quasi-experimental designs, cohort studies, case series, and qualitative research.
- Validity threats: selection bias, attrition, confounding, measurement bias, and publication bias.
- Effect size vs statistical significance: a small p-value does not mean a large or clinically meaningful effect.
- Sensitivity, specificity, and predictive values: predictive values depend on prevalence.
- Critical appraisal: check sample, comparison group, outcome measures, and whether conclusions follow from the data.
Common question traps
Questions often equate statistical significance with clinical importance, or assume a single study proves a causal claim. Another trap is treating expert opinion as equivalent to a systematic review, or ignoring base rates when interpreting a screening result.
Worked example / rule of thumb
A study reports a significant improvement (p < 0.01) with a small effect size in a small sample with 40% attrition. Rule of thumb: significance is not enough. Appraise the effect size, attrition, and sample before changing practice; consider whether the result would hold in your setting and with your client population.