Clinical Trials, Placebo Effects, Complementary Medicine Flashcards
The placebo effect is particularly profound in clinical trials of which type of drug?
Anti-depressants
What were the conclusions of the House of Commons Science and Technology Committee report on homeopathy in 2010?
That it is ‘scientifically implausible’
What were the advantages in the randomised controlled trial with acupuncture vs. Usual care in treatment for chronic headaches?
In those who had received acupuncture:
- there was greater reduction in headache severity at 12 months
- fewer headache days per year
- improved quality of life
- less medication, fewer GP visits, fewer days off
- cost effective; less expensive than Sumatriptan
What needs to be clearly defined in a clinical trial?
The objective needs to be clearly defined
Questions can be prioritised into primary & secondary objectives
What is the possible issue with complementary / alternative medicine?
Much of it is not evidence-based and doesn’t stand up to scrutiny
What is the placebo effect
Effect of a treatment arising from a patient’s expectations and response to the treatments, excluding the actual action of the treatment
*in medicine - the response observed after inert / inactive treatments
What is the nocebo effect?
People reporting adverse side effects after taking a placebo
What is the difference between ‘Superiority’ and ‘Non-inferiority’ in clinical trials?
Superiority - designed to show that one treatment is better than the other
Non-inferiority - designed to show that a new treatment is ‘not unacceptably worse’ than the current standard treatment
What is the % of complementary medicine that is provided privately?
90%
What is ‘Superiority’ in treatment comparison?
Used to demonstrate that one treatment is better than another
(Needed in placebo trials)
What is ‘Non-inferiority’ (in treatment comparison)?
The non-inferior margin is the pre-determined margin of difference between new and standard treatments.
It represents how much worse the new treatment can be compared with standard treatment, and yet still be considered ‘similar’ or ‘not worse’ than standard treatment.
Used to evaluate other factors (i.e. cost / side effects)
What is homeopathy?
Applied the principle of ‘like cures like’
‘a form of complementary medicine in which ailments are treated by minute doses of natural substances that in larger amounts would produce symptoms of the ailment’
So a substance is highly diluted, effectively a sort of placebo
What is ‘Equivalence’ (in treatment comparison) ?
Used to demonstrate that a treatment is the same - no better or worse, than an existing treatment
Also used to evaluate other factors (i.e. is it better in terms of side effects / cost?)
What is considered the ‘gold standard’ for clinical trials?
Randomised clinical trials
I.e. randomly allocating treatment to different people / randomly allocating people to different treatment
What is an open label clinical trial?
Both the clinical / patient know which arm / intervention they are receiving
What is a single blind clinical trial?
Patient is unaware of their treatment assignment
What is a randomised clinical trial?
Patients are randomly allocated to different arms / treatments in the trial
What is a placebo controlled clinical trial?
Some patients get the ‘active’ therapy and some get a placebo
This has to be at least single-blinded as the patient cannot know whether they are receiving the active or placebo treatment
What is a parallel arm clinical trial?
Standard A vs. B
People are randomised
Comparison of 2 interventions / treatments
What is a multi-arm, multi-stage clinical trial?
Enables an undergoing trial to stop or add arms as it continues recruitment, and to evaluate the efficacy of certain arms of the trial
(An arm of a clinical trial is a group of patients receiving a specific treatment, or no treatment)
What is a factorial clinical trial?
Tests all combinations of 2 or more treatment regimens
E.g.
Testing A vs. B
then A with placebo / B with placebo
This can be done with fewer people
What is a double blind clinical trial?
Neither the clinician / patient know whether they are receiving the active / placebo treatment
What is a cross-over clinical trial?
Every patient has both treatments (i.e. A then B or B then A)
What is a cluster randomised clinical trial?
Participants are randomised by unit (e.g. GP surgery, family, community)
