EM · Research, EBM and biostatistics

Research, evidence-based medicine and biostatistics — appraising and applying evidence at the bedside

Also known as Evidence-based medicine · EBM · Critical appraisal · PICO · Number needed to treat · NNT · Likelihood ratio · Sensitivity and specificity · Confidence interval · Type I error · Type II error · Statistical power · Forest plot · GRADE · CONSORT · PRISMA

Research, evidence-based medicine and biostatistics — Sackett's definition of evidence-based medicine as the integration of best research evidence, clinical expertise and patient values; the hierarchy of evidence from meta-analysis and systematic review through randomised controlled trial, cohort, case-control, cross-sectional and ecological designs down to case series and expert opinion; formulating the focused clinical question with PICO (Population, Intervention, Comparator, Outcome); the three-question critical appraisal of validity, results and applicability; the measures of treatment effect — absolute and relative risk reduction, number needed to treat and to harm (NNT and NNH, Laupacis); the measures of diagnostic test performance — sensitivity, specificity, predictive values and likelihood ratios (Jaeschke); statistical inference — confidence intervals, p-values, type I and type II errors and power; synthesis of evidence in meta-analysis with heterogeneity (I-squared, Higgins), forest and funnel plots and publication bias; grading the body of evidence with GRADE and the risk-of-bias tools (Cochrane RoB 2, ROBINS-I) and the reporting guidelines (CONSORT, PRISMA, STROBE, QUADAS-2); and the differential of good versus poor quality evidence. ACEM-primary, globally tagged.