CMB2000/L06 Clinical Trials II Flashcards
Define ethics.
Moral principles that govern a person’s behaviour or the conducting of an activity
What is informed consent?
An intent that human participants enter research voluntarily with full information about what it means for them to take part and that they give consent before they enter the research
What is bias?
Systematic errors that encourage one outcome over others
Investigators may come to the wrong conclusions about beneficial and harmful effects of interventions
Define a control group.
The standard to which comparisons are made in an experiment
A group of participants who do not receive experimental treatment
How are control groups allocated?
Clinician choice
Patient choice
Different consultants
Different hospitals
Consenting and non-consenting groups
ALL can lead to bias
Define randomisation.
The process by which treatments are assigned to participants by chance rather than choice
To avoid bias
Give 3 types of randomisation.
Simple
Block
Stratified randomisation
What is simple randomisation?
Based on a single sequence of random assignments
Give an advantage and a disadvantage to simple randomisation.
+ simple
+ easy to implement
- could result in unequal number amongst groups
What is block randomisation?
Designed to randomise subjects into groups that result in equal sample sizes
Give an advantage and a disadvantage of block randomisation.
+ balance in sample size
- can predict blocks
- groups may not be comparable in terms of covariates
What is stratified randomisation?
Addresses the need to control and balance under influence of covariates
Achieved by generating a separate block for each combination of covariates
Give an advantage and a disadvantage of stratified randomisation.
+ simple for small trials
+ takes covariates into consideration
- complicated if many covariates
- subjects have to identified before assignment
Give 2 practical considerations of randomisation.
Central telephone or web randomisation is ideal
Sealed opaque envelopes
What is blinding?
Studies designed to prevent members of research teams and study participants from influencing results
Who knows which treatment is assigned in single-blinded studies?
Only the researcher
Who knows which treatment is assigned in double-blinded studies?
No-one until the trial is over
What is the process of hypothesis testing?
Test if the alternative hypothesis (H1) is more probable than the null hypothesis (H0) using statistics
Give 3 considerations when setting up and running a clinical trial.
Blinding
Consent
Controls
Randomisation
Sample size
What is the true endpoint of a clinical trial?
A clinically meaningful endpoint that directly measures patients
What is a surrogate endpoint of a clinical trial?
A measurement of a specific outcome used in place of another as a predictor to tell if a treatment works
Usually occurs before a true endpoint and yields conclusions about effect of treatment on true endpoint
What is dissemination of results?
Getting the findings of your research to the people who can make use of them to maximise benefit of the research
Give 3 principles of good dissemination.
Stakeholder engagement
Format
Utilise opportunities
Context
Timing
Give 3 things to consider when disseminating results.
Objective
Audience
Timeline
Resources
Strategy
