evidence based medicine & practice

Question 1

what is evidence based medicine

Answer 1

the conscientious, explicit and judicious use of the best evidence in making decisions about the care of individual patients

Question 2

what does the practice of evidence based medicine mean

Answer 2

integrating individual clinical expertise with the best available external clinical evidence from systematic research

Question 3

when was the EBM movement

Answer 3

1990s

Question 4

what was the EBM movement against

Answer 4

• paternalistic decision making (doctor knows best)
• hierarchies of medical authority (specialist knows best and does best)
• knowledge limited to the few
• subjective self assessment of practice

Question 5

what did the EBM movement move towards

Answer 5

• shared decision making (doctor and patient know complementary things )
• science (clinical evidence) above authority
• development and dissemination of skills to use clinical evidence
• evaluating whether practice is in keeping with evidence

Question 6

what are the five key elements of EBM

Answer 6

1) finding evidence (asking the right questions )
2) assessing the evidence (critical appraisal)
3) synthesising the evidence (bringing it all together )
4) making good decisions
5) evaluating performance against the evidence

Question 7

define evidence

Answer 7

information to inform clinical practice that is obtained by scientific methods

Question 8

what are the 4 major study designs as sources of evidence

Answer 8

1) cross sectional survey
2) case control
3) cohort
4) randomised controlled trial (RCT)

Question 9

what is an observational study

Answer 9

studying what is happening to people

Question 10

what is an experimental/intervention study

Answer 10

studying the effect of an intervention or treatment

Question 11

define sample

Answer 11

the people on whom the study is conducted

Question 12

define exposure

Answer 12

whether/ how much the individual is exposed to the things that are hypothesised to influence the outcome

Question 13

define outcome

Answer 13

the thing you are interested in happening (or not happening)

Question 14

how do you carry out cros sectional study design

Answer 14

start with population
see how many have the dato variables

Question 15

how do you carry out case control study design

Answer 15

take sample of people with one problem and a sample of people with the other
compre the prevalence and match who have both

Question 16

how do you carry out cohort study design

Answer 16

take a sample of unaffected people and measure exposure to the risk factor
after a period of time record how many people in the exposed / unexposed group develop the outcome
but differences may still be due to other factors

Question 17

how do you carry out randomised controlled trial (RCT)

Answer 17

take a sample of patients with condition or risk of interest
randomly allocate one group to intervention or control
follow them for a period of time and measure outcome
randomisation reduces risk that any difference is due to unknown or unmeasured factors

Question 18

what is the hierarchy of evidence ( best method to worst)

Answer 18

1) RCT
2) cohort
3) case control
4) cross section
5) case series

Question 19

how do you structure a question to look for evidence

Answer 19

PICO

patient or population (under study)

intervention(exposure, treatment or procedure)

comparator/control (that which is compared against the intervention)

outcome ( endpoint of interest)

Question 20

what are some sources of evidence

Answer 20

• high quality guidelines (eg NICE, international speciality organisations)
• systematic reviews eg Cochran reviews and structured evidence summaries
  -databases eg MEDLINE, EMBASE, CINAHL, Pubmed)
• grey literature - published but not peer reviewed eg project repostas
• medical journals, reference books

Question 21

how to assess evidence (critical appraisal)

Answer 21

• did it use an appropriate design
• is it at low risk of bias
• was it well conducted
• has it been well reported
• is it making claims justified by its scope and findings

Question 22

what are the tools for critical appraisal

Answer 22

• critical appraisal skills programme ( CASP)
• NICE guidelines manual checklists
• Cochrane handbook for systematic reviews for intervention - cochranes collaborations tool for assessing risk of bias

Question 23

how do you synthesise evidence

Answer 23

narrrative synthesis - describing the results and telling their story

meta analysis - statistical technique for combining the results of multiple studies

qualitative synthesis

Question 24

how do you make good decisions

Answer 24

1) is the evidence good enough that I should use it in my clinical decision

2) does it apply to the patient in front of me

3) how should we make the clinical decision
- doctor led
-patient led
- shared decision

Question 25

how do you evaluate performance

Answer 25

• EBM isn’t a single once off step but a process of ongoing reappraisal
• is the evidence I used before still robust
• am I actually doing what the evidence tells me is the best thing
• am I confident in the evidence, am I simply imposing it on people or am I using it to make shared decisions with patients