Stats Flashcards
what is a theory
an organized set of beliefs about a phenomenon
what is internal validity
list the three criteria required:
the extent to which the association between x and y is causal in nature
- statistical association between variables
- temporal precedence
- nonspuriousness
what is statistical conclusion validity
examines whether there is a statistical association between x and y, and what the magnitude of the relationship is.
some issues can include statistical significance, effect size, and statistical power
what is construct validity
the extent to which conclusions can be made from a test regarding the higher order construct.
e.g. did you capture all aspects of the construct?
what does random assignment to groups do in the context of a group-based randomized experiment?
it precludes systematic pre-test group differences because the groups are probabilistically equated on all measured and unmeasured constructs
what is an efficacy trial
conducted in ideal circumstances to see fi an intervention has an effet
what is an effectiveness trial
conducted in real-life setting to see if an intervention can actually lead to changes as it might be implemented in the community
what is the purpose of intent-to-treat analyses?
to provide a conservative (and real-world) estimate of the treatment effect, which includes cases exposed to varying levels of treatment
what is an ABAB design?
a type of single-case experiment that examines:
baseline (A)
intervention (B)
baseline (A
intervention (B)
what is a multiple-baseline design
capture baseline data of several behaviors, then monitors how these behaviors change after implementation of some intervention
what are things you look at when evaluating a single-case experiment?
mean changes
level shifts
slope (or function) changes
what is a quasi-experimental study and what are two common examples of these?
when you can’t do random assignment
- when patients self-select to an intervention
- when intact groups (e.g. patients at different community health centers) are differentially exposed to treatment conditions
researcher has to figure out how to rule out these threats to internal validity
what is an interrupted time series design?
you collect data consistently before and after an intervention
what is a regression discontinuity design?
you compare groups who are just above vs. those just below a cutoff score
e.g., you look at people who score 79 and dont get a scholarship with those who score 80 and do
what is a case-control design?
comparing a group of participants with a certain characteristic (e.g., those with ADHD) to a group without that characteristic
what is a cohort design?
you follow an intact cohort over time to examine emergence or changes in the variable of interest.
this is a LONGITUDINAL design.
you can use multiple cohorts of different ages to get a cross-sequential design (AKA accelerated longitudinal design) (and shorten the time you have to gather data)
how are multiple cohort designs different from case-control designs?
multiple cohort: groups differ on exposure to something (e.g., poverty)
case control: groups differ on central characteristic (e.g., ADHD)
how to evaluate the potential impact of internal validity threats to your study
in single group studies: threat to validity has to be capable of producing the pattern of results observed
in multiple-group studies: threat needs to be capable and vary systematically by group
what is external validity?
how well the results can generalize, or under what conditions the intervention can work.
threats include:
what are interactions/limits of the intervention? (e.g., does this work for different genders, SES, race/ethnicity)
list the three basic principles of the Belmont report
beneficence
respect for individual’s autonomy
justice (equitable distribution of potential risks/benefits)
