... cause, which we observe, is just along for the ride. e example of caeine, cigarettes, andcancer was given in Chapter 1. Another key example is the case of hormone replacementtherapy (HRT). ... researchers decided to check on their patientsa decade later to examine mortality as a post-hoc outcome (an outcome they decided toexamine long after the study was over). Next one sees that the ... think about theillness.Recall classic examples from medical epidemiology, repeated here from Chapter 4 so thatthis distinction is clear. Here is an example of eect modication: cigarette...