Hi everyone, and welcome to Module 5 of Epidemiology 2.
Now that we've reviewed epi study designs,
measures of disease frequency and association,
and some of the inferential statistics,
we're going to turn our attention
to threats to internal validity.
This is what we'll be spending pretty much
the rest of this course talking about.
If you remember back to Epidemiology 1,
threats to internal validity include bias,
confounding, effect modification or interaction,
and also random chance.
We're going to start here in Module 5
by talking about bias.
Bias is inherent to our study designs.
It's not something that we can control for
or adjust for in our analysis after the study is complete.
So we have to be really careful in our study design
to minimize bias as much as we possibly can.
If you have questions, please reach out.
I'll see you in the next module.
Take care.