Question 3 "In the scenario described in the above case-control study adolescents with mental illness were identified from five adolescent clinics in South Western Sydney (Question 2) and the control were matched by gender and age from the same neighbourhoods of the cases. Is this study prone to selection bias? Please justify your answer if yes, or if no".

Question 4 a) "Is the scenario described in the above case-control study ( Question 2) prone to measurement bias? Explain why." "b) "Would it affect the OR and if yes how"?