You  should take the following quizzes after you finish the corresponding lecture.  For example, take quiz #1 after you complete reviewing the lecture notes and video for lecture 1.

Quiz 1 on Lecture 1: Epidemiology and Study Designs

Quiz 2 on Lecture 2: Systematic Reviews and Meta Analysis

Quiz 3 on Lecture 3: Guides to Medical Literature Appraisal 1

Quiz 4 on Lecture 4: Guides to Medical Literature Appraisal 2

Quiz 5 on Lecture 5: Health Surveillance: Risk Factors, Disease Burden & Indicators

Quiz 6 on Lecture 6: Applied Statistics 1

Quiz 7 on Lecture 7: Applied Statistics 2