Excellent. Bias, Confounding and Effect modifier are important issues to consider in a research. I indicate for all professionals to learn because is crucial to select scientific studies with confidence grade and as well do researchers more accurate.

The course simple and clear provides efficient training for some aspects of statistics (esp confounding). Only what was little cons - I waited several days for peers' homework uploading, to review them. Overall - I recommend the course.

Excellent concise course on the fundamental aspects of epidemiology related to validity, bias, confounding and effect modification.

This course my favourite out of the 3 within the Epidemiology Specialisation.

Cobrehesive, Illustrated in an easy not complicated approach, I enjoyed it

very helpful courses, presented in a very simplified and concise way

Thank you a lot for providing the greatest opportunity.

It is a good course about validity and bias

Excellent course, very complete.

GOOD