Interventional Studies Flashcards
Pre-Clinical
Non-human subjects (tissue/animals)
Phase 0
“Exploratory or Investigational”
Healthy and/or diseased
Very small sample
Short duration (single dose or few days)
Phase 1
Assess safety/tolerance and Pharmacokinetics
Healthy or diseased patients
20-80 subjects
Few weeks duration
Phase 2
Assess effectiveness
Diseased Only
100-300
Few weeks to months duration
Phase 3
Final Pre-FDA stage Disease Volunteers 100-3000 participants Time Frame: few months to years Introduction of statistical perspectives
Phase 4
Diseased Volunteers
Assess long term safety, effectiveness and optimal use
Duration: Few weeks, several years. “Ongoing”
What are the advantages of Interventional trials?
Demonstrates causation
Only design used for FDA approval
What are the disadvantages of Interventional trials?
Cost
Complexity/time
Ethical considerations
Generalizability or external validity
Explain the difference between exploratory and explanatory studies?
Exploratory is the default, pre-set and non-clinical study design looking at effectiveness, safety and toxicity.
Pragmatic studies are more flexible and lifelike that explains qualities but can allow confounders and loss of precision of control.
All studies can be _____ or _____ .
Simple or factorial
Further, all studies are ____ or ____.
cross-over and parallel
Unlike Pragmatic trials, Simple tries use a ____ hypothesis at a time.
Single
What are the effects of using a factorial study design? (5)
Improves efficiency for answering clinical questions Increases study population sample size Increases complexity Increases risk of drop outs May restrict generalizability of results
After randomization, ____ does no allow switching vs _____ does allow switching.
parallel
cross-over
What key words can help us determine if a study is interventional? Use of ____ and _____ when describing tiers of study
Randomization and Phases
What is the difference between wash-out and lead-in?
Wash-out is a period of time when no treatment is given so that the treatment before cross over can clean the system to remove chance of effect contamination. Lead-in is the same situation but occurs before a study.
What is the benefit of lead-in?
Test patient’s compliance by practicing study protocol with study subjects
Also removes drugs that could interact with drug treatment in clinical trial.
Can be accomplished by given placebo for “standardization”
What are the disadvantages of cross-over design?
Only for LT conditions that are not curable or for ST relief
Duration of study is longer including washout
Data analysis complexity
What are the three forms of randomization?
Simple, Blocked and Stratified
What is blocked randomization?
A type of modern randomization that guarantees relative equality. When using blocks, towards the end of the block we as researchers will analyze the groups and move around remaining #s in the group that have not been assigned in groups to allow balance.
____ is used to assess adequacy of blinding.
Post-hoc survey’s
What are ways that placebo therapy is used to look similar?
In terms of dosage form, frequency, therapy requirements and monitoring
Double Dummy is when ____
More than 1 placebo is used
