cross-sectional study
longitudinal study
case control study
confounding variable
variable (not independent variable) that influences the dependent variable
related to research design
usually try to CONTROL for these variables
mediating variable
prove a MECHANISM to explain the relationship between the 2 variables
can help produce CAUSAL relationships
moderating variable
NOT a mechanism, but affects the STRENGTH of the relationship
affects how much the independent variable affects them
affects the already-established relation between IV and DV
placebo effect
effect produced by a placebo treatment that cannot be attributed to the properties of the placebo itself, so its due to person’s BELIEF about treatment working
FINER method
if a study is Feasible, Interesting, Novel, Ethical, Relevant
Hill’s criteria
help determine strength of a causal relationship
only temporality is necessary for causality!!!
SD distribution
selection bias
sample differs from the population
eg. not randomly selected
detection bias
educated professionals using their knowledge in an inconsistent way by searching for an outcome disproportionately in a certain population
hawthorne effect
behaviour of subjects is altered due to the fact they know they are being monitored
social desireability bias
type of response bias, tendency to answer in a way that would be favoured by others
positive control
negative control
validity
ACCURACY
ability to measure true value
reliability
PRECISION
read consistently / narrow range
4 ethics in medicine
3 ethics in research
internal validity
support for causality
when the dependent variable changed as a result of the independent variable
external validity
support for generalizability, higher with large samples or more representative samples of larger population
statistical significance
not the result of random chance
p values
clinical significance
is there a worthwhile change in health status as a result