Imagine you are an intern at your state health department, which has just launched a new initiative to reduce risk-seeking behaviors among adolescents. The Commissioner asks you if you think that internet use among adolescents is "a cause" of risk-seeking behavior (e.g., smoking, drinking, skipped meals, irregular sleep habits, and sexual activity). You think back to your Introduction to Epidemiology class and recall that epidemiologists have a fairly distinct definition of "cause".

Which of the following statements best describes the hypothesized causal link between internet use and risk-seeking behaviors, and why? For the other 2 statements, why do they not describe the causal link?

All individuals with long hours of Internet use during childhood will go on to risk-seeking behaviors in adolescence.

All individuals who initiate risk-seeking behaviors in adolescence would have been exposed to substantial internet use during childhood.

Individuals who spend a substantial amount of time on the internet in childhood are more likely to initiate risk-seeking behaviors in adolescence, compared with those individuals who use spend little or no time on the internet during childhood.