Quiz 8, Module Causal
8. Which of the following alternative explanations could have possibly caused the authors to find that youth who watched >5 hours of television per day were 5.99 times more likely to initiate smoking behaviors, if watching TV did not truly cause smoking initiation?
- If a true cause of smoking initiation was poor parental monitoring, and youth who watch a lot of TV are less likely to be monitored by parents, then the association between TV watching and smoking initiation would really be due to their shared association with parental monitoring. This is an example of confounding .
- Youth who watch TV are more likely to under-report true smoking habits on a survey compared to youth who do not watch TV.
- Youth who watch a lot of TV are more likely to have participated in the follow-up survey since they have more free time.
Answer (a) —
correct:
If the true cause was being home alone after school, and youth who watch TV are more likely to be home alone after school, then the association between TV watching and smoking initiation would really be due to their shared association with being home alone after school. This is an example of
confounding
.
Answer (b) —
incorrect:
If that were the case, then it would appear that TV-watchers are LESS likely to initiate smoking.
Answer (c) —
incorrect:
For this type of phenomenon to explain the results, the youth who watched a lot of television AND started smoking early would have to be disproportionately followed-up, compared to children who watched a lot of television and did not initiate smoking early.
