General Methodological Concepts of Research Flashcards
Name the 2 types of Quantitative Studies
Interventional and Observational
Describe Interventional Study Design characteristics
aka. “experimental” have forced allocation study groups and have the potential to be less ethical
Describe Observational Study Design characteristics
observe subject elements occurring naturally or elements that subjects choose to be a part of
there is no researcher-forced group allocation
Describe the relationship observational studies have with proving causation
observational studies cannot prove causation
List Interventional study designs in increasing level of evidence
phase 0, phase 1, phase 2, etc
List Observational study designs in increasing level of evidence
Case reports
Ecological
Cross-sectional
case-control
cohort
Define the null hypothesis in a study
a research perspective which states there will be no (true) difference between the groups being studied
researchers either reject or dont reject this perspective based on the results obtained via data analysis
What are the 3 various statistical-perspectives that can be taken by the researcher for the null hypothesis?
Superiority
Noninferiority
Equivalency
Explain the Superiority null hypothesis perspective. What is a common comparison it is used for?
the null hypothesis is “im not superior”
asks the question “I wonder if im better”
usually used when comparing to placebo
Explain the Noninferiority null hypothesis perspective. What is a common comparison it is used for?
The null hypothesis is “im not worse”
asks the question “I wonder if im not worse”
Usually used to compare a new treatment to something that is already accepted to be effective
Explain the Equivalency null hypothesis perspective. What is a common comparison it is used for?
The null hypothesis is “Im not equivalent”
asks the question “I wonder if im equivalent”
True or False: Studies that yield a rejected null hypothesis of superiority are said to be less effective than what they were being compared to.
False
After a superiority null hypthesis is rejected, the relationship could still be either “noninferiority” and “equivalency”
Compare probability and non probability samples
probability sample: every element in the population has a known probability of being included in the sample
Nonprobability sample: every element in the population does NOT have a known probability of being included in the sample
In terms of probability sampling schemes, define Simple Random Sampling
assigning random numbers, then taking randomly selected numbers to acquire the desired sample size
(or assign random #’s and then take a sequential order of the randomly given numbers)
In terms of probability sampling schemes, define Systematic Random sampling
assigning random numbers, sort these numbers, and then select subjects via a predetermined sampling interval (take every Nth numbers) to get the desired sample size
In terms of probability sampling schemes, define multi-stage random sampling
uses simple random sampling at “multiple stages” towards patient selection
Ex. Take simple random samples out of one country, then out of one zip code, then out of one household, then out of one person
In terms of probability sampling schemes, define clustered multi-stage random sampling
basically multi stage random sampling, however ALL elements at each stage are included in the study
Ex. ALL clinics in a zip code and then ALL households in a community
In terms of probability sampling schemes, define Convenience (Quasi-systematic) sampling
aren’t really completely random. The researcher decides what fraction of the population is to be sampled and how they will be sampled.
Ex. All persons with last names C-D, all members that work for the same business, all MWF visitors of a clinic
In terms of probability sampling schemes, define stratified random sampling
collecting subjects in different strata based on a desired characteristic (may be a known confounder) and then using simple random sampling to get the desired sample size
In terms of probability sampling schemes, define stratified disproportionate random sampling
Collecting subjects in a stratified manner that helps achieve a desired proportional representation of a underrepresented portion of the population.
over sampling is an example of this, however over sampling requires a “weighted” return sample population back to the baseline population
Describe the difference between patient-oriented outcomes and disease-oriented outcomes.
pt-oriented outcomes: avoiding a MI (things that most patients care about)
Disease-oriented outcomes: cholesterol number (most patients dont care about their cholesterol number if it isnt actively affecting them)
Describe internal validity as it applies to methodology of study
methods inside of the study affect the internal validity of the study.
high internal validity means that the study is scientifically rigorous/standardized and the results are accurate/reproducible.
True or False
3 of the 4 principles of bioethics must be met by a study in order to be ethical.
False
all 4 principles must be met
List and describe the 4 principles of bioethics.
Autonomy: participants fully understand all of the risks/benefits that could occur in the study, and willingly volunteer for it
Beneficence: the researchers must have good reason to believe that the treatment will benefit the patient NOT society
Justice: equal and fair treatment of all patients must occur
Nonmaleficence: researchers must do no harm to subjects (no lying/witholding to subjects)
