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The first 25 slides, exactly as they appear. The full deck has 145 content slides.
Orthopaedics
Foundations of Research Methodology, Evidence Hierarchies, and Trial Quality
Built from Orthopedic Trauma Essentials
What’s inside
13 sections · 145 slides
Why research methods matter in trauma
High-stakes decisions, made fast, on mixed evidence
- The decisions that come first
- Why the evidence is often mixed
- What evidence-based medicine really means
- Two extra skills a trauma reader needs
- Three questions to ask of any study
- The three questions, spelled out
Framing the question
From PICO to estimand, and where the clock starts
- Start with a question you can answer
- PICO with a trauma example
- What an estimand adds
- Intercurrent events are normal in trauma
- Time zero: where the clock starts
- How a fuzzy clock fakes a benefit
- How a mis-set clock invents a benefit
Evidence hierarchies
A useful shortcut with two important cautions
- What an evidence hierarchy is for
- The classic pyramid, top to bottom
- The evidence pyramid, from case series to systematic reviews
- Two cautions before you trust the ranking
- The level depends on the question
- Four question types, four ladders
Systematic reviews and meta-analysis
Comprehensive by design, and fragile in specific ways
- What a systematic review is
- What a meta-analysis adds
- Why syntheses sit at the top
- A review inherits the level of its studies
- What makes a review credible
- Extra checks when the numbers are pooled
- Reading the study-selection flow chart
- Tracking studies from database search to final inclusion
- Pooling study results into one summary estimate
- Checking whether studies are missing
- How a systematic review goes wrong
- Biases that keep coming back in trauma research
- Common sources of bias in orthopaedic trauma research: what each one means
- Common sources of bias in orthopaedic trauma research: setting, effect and mitigation
- The two biases to spot first
Randomized controlled trials
What randomisation buys, and what it cannot protect
- What a randomized trial is
- Why randomisation is so powerful
- The label is not the proof
- Sequence generation and allocation concealment
- Blinding when the operation is visible
- What to do when the surgeon cannot be blinded
- How participants flow through a parallel randomized trial
- Five ways a randomized trial still goes wrong
- Trial variants: cluster and stepped-wedge
- Trial variants: factorial and adaptive
Quasi-experimental designs
Causal questions when randomisation is off the table
- When you cannot randomize
- What quasi-experiments buy you
- What a credible quasi-experiment needs
- Where quasi-experiments go wrong
- Three ways to build the comparison
Observational analytical designs
The workhorse of trauma literature, and its blind spots
- Why observational studies dominate trauma
- Four observational designs
- Cohort studies start with the exposure
- Why retrospective cohorts are common - and risky
- What a credible cohort needs
- How cohort studies go wrong
- Missing data in trauma registries
- Controlling confounding after the fact
- What propensity scores cannot do
- Case-control studies start with the outcome
- What a good case-control study looks like
- How case-control studies go wrong
- Cross-sectional studies: a single snapshot
- Getting a snapshot right, and what spoils it
- Case series: description without a comparator
- What a good case series still requires
- How case series mislead
- Telling the three designs apart
Diagnostic, prognostic and registry research
Three question types the therapy pyramid does not fit
- Diagnostic accuracy studies
- What a good diagnostic study needs
- Five biases that flatter a test
- Prognostic studies and prediction models
- What a prediction model must report
- How prognostic studies go wrong
- Registries and routine data
- Reporting standards for routine data
- The registry-based randomized trial
- What registry research must specify
- How registry studies go wrong
What makes any study strong
Power, endpoints, missing data and consent
- Sample size and power
- Multiplicity: the more you test, the more you find
- Surrogate versus patient-centred endpoints
- Measuring what matters to patients
- Missing data and loss to follow-up
- Intention to treat, and testing robustness
- Consent when the patient cannot give it
- Recognised routes around standard consent
- The current ethics and practice standards
Certainty of evidence
GRADE, and what to do when the evidence is thin
- GRADE separates two judgements
- The five things that lower certainty
- Four levels of certainty
- Why GRADE suits trauma
- Acting on high versus low certainty
- Strength of recommendation is more than evidence
Appraising quality and risk of bias
Which tool for which design, and what each one outputs
- What trial quality actually means
- The recurring weak points in trauma work
- What to look for without any tool
- Tools follow the design
- Risk-of-bias and methodological appraisal tools by study design
- The appraisal toolkit at a glance
- RoB 2: the standard for randomized trials
- How a RoB 2 judgement is reached
- A risk-of-bias grid across trials and domains
- Other checklists for randomized trials
- ROBINS-I: bias in non-randomized studies
- What ROBINS-I produces
- MINORS: a score for surgical studies
- ROBINS-I or MINORS?
- The Newcastle-Ottawa Scale
- Checklists for case reports and case series
- AMSTAR 2: judging the review itself
- What AMSTAR 2 tells you, and its neighbours
- Tools for diagnostic accuracy studies
- TRIPOD and its extensions
- PROBAST for prediction model bias
- Reporting guidelines, one per design
- Reporting guidelines relevant to orthopaedic trauma research
Using the evidence at the bedside
A five-step workflow, and three worked examples
- A reproducible way to read a paper
- Step 1: clarify the decision
- Steps 2 and 3: is it true, and how big?
- Steps 4 and 5: does it fit, and what now?
- Aspirin or injectable heparin after fracture surgery?
- Reading the thromboprophylaxis trial
- Which irrigation for an open tibia fracture?
- Reading the wound irrigation trial
- Reamed or unreamed nail?
- Reading a composite endpoint carefully
Take-home points
What to carry into the next paper you read
- Design and question first
- Judge credibility, then relevance
- Then decide, and stay ready to change
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- Orthopedic Trauma Essentials 2026