Randomized Control Trials Flashcards
What are the stages of drug development?
Preclinical, Volunteer studies (phase I), treatment studies (phase II), clinical trials (phase III) and post market surveillance.
What are the advantages of randomly allocating a trial?
Minimal allocation bias, minimal confounding (as randomisation should lead to similar groups) and people are allocated fairy without selection bias.
What are the types pf outcome that can be measured in a clinical trial?
Clinical outcomes: death, disease, disability
Pathophysiological outcomes: tumour size, thyroxine level, ECG changes.
Patient focused: quality of life, satisfaction, psychological wellbeing, social wellbeing
What are the two different types of outcome that can be measured?
Primary outcome (preferably only one, can be used in the sample size calculation) and secondary outcomes such as the indicindence of side affects.
Define efficacy
Ability to improve the health of a defined group under specific conditions
Define safety (in the context)
Ability of am intervention to not harm a defined group under specific conditions.
What are the two methods of allocation?
Open label and blinding or masking
What are the disadvantages of using an open label approach?
Patient may alter their behaviours, use another treatment or alter their expectations of outcome, the clinician may alter their interest in the patient, and the care given to the patient. Investigator may alter their approach when assessing outcomes.
Define the placebo affect
Patients attitude to illness and illness itself may improve due to the feeling that something is being done about it.
What are the main reaSons for losses to follow up?
Clinical condition may nessicate removal from the trial or the patient may choose to withdraw .
What are some of the reasons for patient non compliance?
The patient may not like taking the treatment, may not think the treatment is working, may have misunderstood the instructions.
What are the features of an as treated the analysis?
Analysis only of those who completed follow up and treatments , it tend to gives larger effect sizes, but looses effects of randomisation, as people who stop the treatment tend to be different to those who continue on the treatment.
What are the features on a intention to treat Anaylsis?
Analysis based on original groups whether people completed the treatment or not, it tends to be more repersentive of actual clinical practice and helps to persevere the effects of randomisation.
What to parts should the ethics of a clinical trial be split into?
For the patient and for society as a whole.
What is a clinical trial?
An experiment that involves patients and is designed to elucidate the most appropriate treatment for future use.
