1. Critical Appraisal of a RCT
Dr Donncha O’Gradaigh,
EBP Group South East

2. appraise
ask
assess
acquire
apply

3. Fair tests
Testing Treatments link

4. Clinical scenario…
After a sports event, two of your team-mates are debating whether there is any benefit from anti-inflammatory gel for an ankle sprain

5. Validity reliability significance

6. PICO - matching Patient / Population Intervention Control / comparison
Will the results be relevant to your patient? Is your patient in a sub-group?
Intervention
Control / comparison
Is the comparison relevant and fair (placebo versus active comparators)
Outcome
Clinically relevant? Patient preference?

7. Some definitions
offer glossary of terms

9. The METHODS section

10. Systematic approaches to appraisal of “reliability” in study design
RAMMbo and GATES

11. RAMMbo Recruitment representative sample – age, symptoms…
of the population?
of the way you will meet the next one (random, consecutive, exclusions)?

12. RAMMbo Allocation Equal chance of either intervention or control
Stratification in randomisation
Computer versus envelopes
“Blind” generally refers only to allocation – no use if subsequent process reveals allocation
“Double dummy”, marks, adverse effects; acupuncture studies

13. RAMMbo Maintenance in the study Protocol violations versus allowed
Consider all the possible differences
Maintain blinding
Record drop-outs
80:20 guide

14. RAMMbo Measurement (of outcome)
Is the measurement appropriate for the treatment
Is the measurement appropriate for your patient’s clinical query
carried out without bias
Blinded (b) assessor or objective (o) tool (both?)

15. R
Mbo M A P
I/C O

16. the Results section- or “is this any use?”

17. “I need a p”

18. Result = truth + bias + random error
DESIGN
Result = truth + bias + random error
MEASURE

19. Understanding bias and error

20. the result is an ESTIMATE from a SAMPLE

21. how do 95% CI and p relate? 95% CI
measured difference between the two arms
If there was no difference between treatment arms
95% CI
The range of values the difference might have

22. Spot the [deliberate] error
“Our results show a highly significant (p<0.001) effect of metwostatin on LDL cholesterol” “our study of 53 individual patients shows that there is no benefit from this intervention (p=0.051)” “While the effect of x-mab on pain did not reach significance (p>0.05), the significant reduction in radiographic progression (p=0.029) is an important benefit of treatment”

23. In the workshop A medication RCT
Methodolgy, RAMMbo
Results – two different types
Your own Clinical Query / group project
A two step intervention
More complex, maybe more real-life
More technical aspects of trial design