What is a retrospective study?
Looks backwards and examines exposure to risk factors in relation to outcome that are established at the start of the study
What can different studies involve comparisions with?
Cross over design
What is a cross over design?
Patient is given additional treatment which is being tested
What is a randomised control study?
One where patients are assigned to one of the groups at random
What are some disadvantages of randomised control?
Generalised (subjects may not represent patient population)
Recruitment (twice as many new patients needed for the study)
Acceptability (some physicians or patients will refuse)
Administrative complexity (randomisation methods etc)
What does superiority design show?
New treatment is better than the control or standard treatment
What does non-inferiority design show?
Not worse than standard treatment by more than some margin
Would have beaten placebo if it had been included
What should the end points of a design be?
Simple, such as:
Number of hospital admissions
Lowering of blood pressure
What do you need to consider when designing a study?
Choice of subjects (enough to be able to detect or reject differences between groups)
Choice of control drug (placebo or another drug)
Choice of patients (age, race, sex, diseases and drugs)
Exclusion and selection criteria (pregnant woman, children, seriously ill patients, elderly)
What are challenges with trials that involve the elderly?
They usually have multiple conditions
What do you need to consider when analysing and interpreting data?
Are differences due to chance
O<0.05 usually taken as significance
What are some ethics that must be considered?
How long can overall development of the drug from initial research to its first launch take?
Up to 20 years
What is post marketting surveillance done by?
Medicines and Healthcare devices Regulatory Authority (MHRA)
Yellow card system