EIP FINAL QUESTIONS AND ANSWERS
What is the difference between a survey and an experiment? - Answers :-Survey-
provide a quantitative/numeric description of trends, attitudes, or opinions of a
population by studying a sample of that population; generalize/draw inferences to the
population
-Experiment-also study a sample and generalize to the population, but tests the impact
of a treatment (or intervention) on an outcome, controlling for all other factors that might
influence that outcome
What guides the study design? - Answers :the research question
when doing a survey design, what are the checklist criteria to look at? - Answers :-check
the purpose
-cross sectional vs longitudinal
-form of data collection
-random sample vs convenience sample
-stratification
-sample size
-instrumentation
what is the difference between cross sectional and longitudinal? - Answers :cross
sectional is data collected at one point in time.
longitudinal is data collected over time.
what is the difference between a random sample and a convenience sample? - Answers
:random-each individual in the population as equal probability of being selected.
convenience-respondents are chosen based on their convenience and availability.
what does stratification mean? - Answers :-Means that specific characteristics of an
individual (ex. gender) are represented in the sample and the sample reflects true
proportions in the population of individuals with certain characteristics
-Requires that characteristics of the population members be known so that the
population can be stratified first before selecting the sample
Sample size is usually based off what? - Answers :selected a fraction of the population
or margin of error they are willing to tolerate.
Study is only as good as the ___ and ___. - Answers :reliability and validity
the larger the sample size, the more you are able to gain meaningful information. T or
F? - Answers :true
, What is a power analysis? - Answers :method used to calculate how many participants
are in a study; based on prior studies on certain topic or run through by a calculator.
What is the difference between independent and dependent variables? - Answers :o
Independent variables-what you do (program)
o Dependent variables-outcomes/outcome measures; what's being measured
what is the difference between internal and external validity? - Answers :o Internal-the
certainty to which we can attribute the study outcome to the independent variable; less
generalizable
o External-relates to the patient population, clinical setting, treatment and measurement
variables that the study can be generalized to
threats to internal validity include... - Answers :history, maturation, testing, attrition,
regression to the mean, selection bias, instrumentation, sequence effects, and
contamination.
How can history threaten internal validity? - Answers :external even can influence study
outcome.
How can maturation affect internal validity? - Answers :time influences studyoutcome;
people change.
how can testing affect internal validity? - Answers :repeated testing of participants
influences study outcome, i.e. the learned effect.
what is the learned effect? - Answers :measuring dependent variables multiples times;
could get better or worse.
how does attrition affect internal validity - Answers :loss of subjects during experiement
influences study outcomes.
how does regression to the mean affect internal validity? - Answers :natural tendency
for people to change towards the average influences study outcome.
how does selection bias affect internal validity? - Answers :bias in selecting individuals
for different treatment groups influence study outcomes
What is a selection-attrition interaction threat? - Answers :when you know what the
selection bias is you name it with the concurrent interanl validity.
how can instrumentation affect internal validity? - Answers :changes to tests and
measurements can influence a study outcome.
how can sequence effects affect internal validity? - Answers :prior experiences in the
study influence current performance
What is the difference between a survey and an experiment? - Answers :-Survey-
provide a quantitative/numeric description of trends, attitudes, or opinions of a
population by studying a sample of that population; generalize/draw inferences to the
population
-Experiment-also study a sample and generalize to the population, but tests the impact
of a treatment (or intervention) on an outcome, controlling for all other factors that might
influence that outcome
What guides the study design? - Answers :the research question
when doing a survey design, what are the checklist criteria to look at? - Answers :-check
the purpose
-cross sectional vs longitudinal
-form of data collection
-random sample vs convenience sample
-stratification
-sample size
-instrumentation
what is the difference between cross sectional and longitudinal? - Answers :cross
sectional is data collected at one point in time.
longitudinal is data collected over time.
what is the difference between a random sample and a convenience sample? - Answers
:random-each individual in the population as equal probability of being selected.
convenience-respondents are chosen based on their convenience and availability.
what does stratification mean? - Answers :-Means that specific characteristics of an
individual (ex. gender) are represented in the sample and the sample reflects true
proportions in the population of individuals with certain characteristics
-Requires that characteristics of the population members be known so that the
population can be stratified first before selecting the sample
Sample size is usually based off what? - Answers :selected a fraction of the population
or margin of error they are willing to tolerate.
Study is only as good as the ___ and ___. - Answers :reliability and validity
the larger the sample size, the more you are able to gain meaningful information. T or
F? - Answers :true
, What is a power analysis? - Answers :method used to calculate how many participants
are in a study; based on prior studies on certain topic or run through by a calculator.
What is the difference between independent and dependent variables? - Answers :o
Independent variables-what you do (program)
o Dependent variables-outcomes/outcome measures; what's being measured
what is the difference between internal and external validity? - Answers :o Internal-the
certainty to which we can attribute the study outcome to the independent variable; less
generalizable
o External-relates to the patient population, clinical setting, treatment and measurement
variables that the study can be generalized to
threats to internal validity include... - Answers :history, maturation, testing, attrition,
regression to the mean, selection bias, instrumentation, sequence effects, and
contamination.
How can history threaten internal validity? - Answers :external even can influence study
outcome.
How can maturation affect internal validity? - Answers :time influences studyoutcome;
people change.
how can testing affect internal validity? - Answers :repeated testing of participants
influences study outcome, i.e. the learned effect.
what is the learned effect? - Answers :measuring dependent variables multiples times;
could get better or worse.
how does attrition affect internal validity - Answers :loss of subjects during experiement
influences study outcomes.
how does regression to the mean affect internal validity? - Answers :natural tendency
for people to change towards the average influences study outcome.
how does selection bias affect internal validity? - Answers :bias in selecting individuals
for different treatment groups influence study outcomes
What is a selection-attrition interaction threat? - Answers :when you know what the
selection bias is you name it with the concurrent interanl validity.
how can instrumentation affect internal validity? - Answers :changes to tests and
measurements can influence a study outcome.
how can sequence effects affect internal validity? - Answers :prior experiences in the
study influence current performance
