[2] Class 15: General Methodological Concepts Of Research Flashcards
What does the research evidence pyramid tell us?
The increasing strength of evidence based on design of research
What is the most useful and appropriate study design?
It depends
Study design uses numbers to represent data
Quantitative
Study design uses words to represent data
Qualitative
2 forms of quantitative study design
Interventional
Observational
Study design forced allocation to study groups
Interventional
Study design that does not force allocation to study groups
Observational
Study design selection can depend on:
Hypothesis Force group allocation (randomization?) Ethics Efficiency and practicality Costs! Validity of acquired info.-internal Generalizability=external validity
Helps frame study intent and can direct researcher to more effective study design to answer question
“I wonder if..”
A research perspective which states there will be no difference between the groups being compared
Null hypothesis
Statistical perspective that one Tx/exposure is better
Superiority
Statistical perspective that tries to prove a Tx/exposure is atleast as good as the other
Noninferiority
statistical perspective that one Tx/exposure is equivalent
Equivalency
Rejecting the null when you shouldn’t have
Type I error
False positive
Not rejecting the null when you should have
Type II error
false negative
If there is randomization, what type of study design is being looked at ?
Interventional
Study design considered “natural”- subject selected elements
Useful for unethical study designs
No researcher forced group allocation
Observational
Can observational study designs prove causation?
Most of the time=NO
Interventional study steps increasing evidence:
Pre-clinical [phase 0] Phase 1 2 3 4
Observation study steps increasing evidence:
Case reports/series Cross-sectional Ecological Case-control Cohort
All individuals making up a common group, from which a sample can be obtained
Population