Research Methods and Evidence-Based Practice
Core concepts
Evidence-based practice integrates the best available evidence, clinical expertise and patient values. Candidates must know study designs: randomised controlled trials, cohort studies, case-control studies, cross-sectional surveys, qualitative studies and systematic reviews. Understand hierarchy of evidence - systematic reviews and RCTs sit at the top for effectiveness questions. Learn key terms: reliability (consistency), validity (accuracy), bias, confounding, sampling methods, informed consent, anonymity and confidentiality. Know the difference between quantitative and qualitative data and the use of descriptive versus inferential statistics. Understand critical appraisal and the PICO framework for formulating questions.
Traps in questions
Do not confuse reliability with validity - a scale can be consistently wrong. Remember that randomisation reduces selection bias but does not eliminate all bias. Questions may confuse incidence with prevalence or correlation with causation. Beware of claims that a single study proves a causal link. Also note that anonymity means the researcher cannot identify the participant; confidentiality means the researcher knows but does not disclose.
Worked rule of thumb
Use PICO: Population, Intervention, Comparison, Outcome. Example: in older adults (P), does a falls-prevention exercise programme (I) compared with usual care (C) reduce falls (O)?
Applying it
Critical appraisal asks: is the study valid, what are the results, and are they applicable to my population?