Table 3.

Vignette dimensions and levels used in this study: experimental variation of five drug characteristics and three characteristics of the social environment

Dimension	Levels
Peer prevalence	A student considers using a prescription drug to enhance her memorization skills for her exam preparation. From a medical point of view, this is not necessary. This student knows that
	▪ none
	▪ every second
	▪ every one
	of her friends or acquaintances uses such substances.
Social suggestions	She
	▪ never
	▪ sometimes
	▪ very often
	gets suggestions from others to try such means.
Magnitude of enhancement effect	By taking such drugs, she hopes to increase the amount of memorized information by
	▪ 5 percent
	▪ a factor of two
	▪ a factor of three
	compared to her normal state.
Probability of enhancement effect	From a recently published study, she knows that that the effect occurs with a
	▪ 5
	▪ 50
	▪ 100
	percent chance.
Probability of side effects	This study also reported that
	▪ one of 1,000,000 users
	▪ one of 1,000 users
	▪ every user
Severity of side effects	developed
	▪ very light
	▪ moderate
	▪ very strong
	depression. Further side effects are unknown.
Drug price	Someone can provide her with a package of 10 pills for
	▪ free.
	▪ 20 Euros.
	▪ 100 Euros.
	This is enough for 20 learning hours.
Social disapproval	The use of such drugs would cause
	▪ no
	▪ moderate
	▪ very strong
	criticism in her environment