Clinical Trails

Question 1

What is efficacy

Answer 1

The ability of an intervention to improve health care of a defined group under certain conditions

Question 2

What is safety

Answer 2

The ability of a health care intervention not to harm a defined group under specific conditions

Question 3

What is a clinical trial ?

Answer 3

Any form of planned experiment which involves patients and is designed to elucidate the most appropriate method of treatment for future patients with a given medical condition

Question 4

What are outcome measures in a RCT ?

Answer 4

Reasons for pre- defining outcomes
Primary + secondary outcomes 
Types of outcomes 
Features of ideal outcome 
Timing of measurements

Question 5

Why do you pre define outcomes ?

Answer 5

protocol for data collection
prevent data dredging and repeated analysis
agreed criteria for measurement and assessment of outcomes

Question 6

what is the difference between primary outcome and secondary ?

Answer 6

primary = is the 1 outcome you measure to prove your hypothesis 
secondary = other outcomes of interest e.g side effects

Question 7

name an example of pathophysiological , clinicially defined and patient focused outcomes

Answer 7

pathophysiological = biomarkers , tumour size
Clinically defined = death , morbidity
patient focused = QoL , social well-being

Question 8

what are the features of an ideal outcome ?

Answer 8

Appropriate and relevant 
valid and attributable 
sensitive / specific 
reproducible and simple
cheap and timely

Question 9

how can we show comparability ?

Answer 9

collect data on characteristics on both the condition and the outcomes we are investigating

Question 10

what makes a trial ethical ?

Answer 10

clinical equipoise - dont know the best treatments for patients
the participants must understand what participation involves

Question 11

what phase is a clinical trial ?

Answer 11

3 , comparison with standard treatment . <10,000 patients

Question 12

What is a phase 1 trial ?

Answer 12

volunteer to see pharmacodynamics , pharmokinetics and side effects . <100 patients

Question 13

What is a phase 2 trail ?

Answer 13

see any effects and dosages and other side-effects. <1,000

Question 14

what does non random allocation lead to ?

Answer 14

allocation bias and confounders

Question 15

what are the problems with historical controls?

Answer 15

selection often less well defined , treated differently form new treatment group. unable to control cofounders

Question 16

what effects and bias arise from open label ?

Answer 16

behaviour effect - patient alters behaviour to treatment given
non-treatment effect = clinician behaviour
Measurement bias = clinician alter approach to measurements

Question 17

what is bias ?

Answer 17

systematic distortion in allocation / measurement

Question 18

what is wrong comparing “treatment “ to “no treatment” ?

Answer 18

the act of treatment may have an affect on the outcomes

Question 19

when should a placebo be used ?

Answer 19

when there is no standard treatment

Question 20

what is “As treated” analysis ?

Answer 20

only look at those who complied with treatment

= loses effect of randomisation as non compliers are different to compliers = selection bias and confounders

Question 21

what is intention to treat analysis ?

Answer 21

analyses both compliers and non-compliers = preserves effects of randomisation . they give smaller and realistic sizes of effect compared to “As treated “