Pharmacology

Question 1

Steps involved in a randomised controlled trial (RCT)

7

Answer 1

1. ID patients eligible for the trial
2. Invite patients to trial
3. Consent from patients
4. Allocate patients fairly - remove bias and confounding
5. Follow up with patients
6. Minimise losses to follow up
7. Maximise adherence

Question 2

Describe two ways you can minimise confounding and bias

Answer 2

Blinding

Random allocation (get minimised allocation bias and minimised confounding)

Question 3

Name 3 types of outcome measures used in a clinical trial

Give an example of each one

Answer 3

1. Pathophysiological (Tumour size)
2. Clinical based (death, disease, disability)
3. Patient focused (QOL)

Question 4

With non-randomised allocation trials, what bias do you have?

Answer 4

Allocation/Selection bias

Question 5

What forms of analysis is present in

A) Explanatory trials
B) Pragmatic trials

Answer 5

A) As-treated analysis

B) Intention-to-treat analysis

Question 6

Describe what the As-treated Analysis looks at

Answer 6

Only looks at the physiological effect of the treatment in patients that have completed follow up

Question 7

What is the disadvantage of As-treated Analysis?

Answer 7

Loses the effects of randomisation:

• allocation/selection bias
• confounding

Question 8

Describe what Intention-to-Treat analysis looks like

Answer 8

Analyses the effects of the trial when being used in clinical practice in all of the people in their original, allocation regardless of whether they fully complied or completed follow up

Question 9

List 4 limitations of early phase trials

Answer 9

1. Limited by age/sex
2. Small sample size
3. Contaminants in real life are not taken into account
4. Short duration

Question 10

How are ADRs reported?

Answer 10

Via the Yellow Card Scheme owned by MHRA

Question 11

Systematic reviews are the most credible sources of evidence.

What is the definition of a systematic review?

Answer 11

A review that uses primary resources that are explicit (so critically appraised) and reproducible - so it uses Analytical studies (Case controlled studies and Cohort studies) [filtered information]

Question 12

A meta-analysis is one of the most credible sources of unbiased and reproducible data.

What is the definition of meta-analysis.

Answer 12

A quantitative synthesis of THE RESULTS of two or more studies that have the same hypothesis and same method

Question 13

What calculations are needed in order to find the weighting in a meta-analysis study?

Answer 13

Odds ratio and 95% Confidence Interval

Question 14

Name 3 issues with meta-analysis studies

Answer 14

1. Heterogeneity between studies
2. Varying quality of studies
3. Publication bias when selecting studies that should be involved in the meta-analytic study

Question 15

What graph is used in meta-analysis studies to show case the data?

Answer 15

Forest plot

Question 16

Regarding the heterogeneity between studies, in a meta-analysis study, which models can be used, when deciding how the data is going to be analysed?

Explain what each model means.

Answer 16

Fixed effect model:
The TRUE EFFECT SIZE seen in each study is the SAME, only thing differing is the Random error

Random effect model:
The TRUE EFFECT SIZE seen in each study is similar