evidence based medicine

Question 1

examples of experimental studies

Answer 1

systematic reviews (combining RCTs)

randomised control trials (RCTs)

Question 2

examples of observational analytical

Answer 2

cohort - prospective, retrospective

case-control

cross-sectional study

Question 3

examples of observational descriptive studies

Answer 3

case reports + case series

-> a report on a series of patients with an outcome of interest, no control group is used

Question 4

what are the 2 types of randomised control trials?

Answer 4

intention to treat RTCs - analysed in randomised group

per-protocol RTCs -analysed in treatment group

Question 5

difference between prospective + retrospective cohort studies?

Answer 5

prospective - cohort followed forward in time from present

retrospective - cohort formed in the past + followed up to the present

Question 6

case-control study

Answer 6

begin with the outcomes and do not follow people over time; researchers choose people with a particular result (the cases) and interview the groups or check their records to ascertain what different experiences they had

(observational analytical)

Question 7

presentation of results of critical appraisal

Answer 7

• Results are assessed using statistical inference testing
• Test used depends on type of data; compare means with t-test, compare proportions with Chi-squared test
• Results declared as a difference between groups with a 95%
  confidence interval - accept or reject the null hypothesis

Question 7

cross-sectional study

Answer 7

the observation of a defined population at a single point in time or time interval; exposure and outcome are determined simultaneously
- Interview a fresh sample of people each time they are carried out
- Vs a longuitudinal study - same sample of people over time

(observational analytical)