Fixed Mindset Items

"The extent to which a person is addicted is something basic about them and it can’t be changed very much."

"A person can learn new ways to break a habit, but they can’t really change their basic addiction."

"Whether a person is addicted or not is deeply ingrained in that person. It cannot be changed very much"

"Even with great effort, some people are not able to change their addiction."

"Once you get addicted, the addiction is always a part of you that won’t ever change even if you manage to stop using the substance."

"People who are addicted will always be addicted to some extent, and they can’t really do much to change it."

"Once an addict, always an addict"

"You can’t really change how addicted you are."

"A person’s addiction can never fully leave them"

"Some people will always be addicted, and there’s not much they can do about it."

"Addiction is something you either have or don’t have.”

Growth Mindset items

"Addiction is a series of choices, and people can end their addiction by making different choices."

"With effort, people can get over their addiction."

"No matter how addicted you are, you can always change quite a bit."

"People can always substantially change how addicted they are."

"People do get addicted, but they can recover from the addiction with effort."

"If an addicted person gets help, they will be able to change."

"You can be addicted a little or a lot, and that can change."

"People who learn from their addiction can overcome it."

"People can learn to control their addictions."

"Anyone can always overcome an addiction."

"If they keep trying despite setbacks, people can get over their addiction."

Note. Bolded items indicate the items that were included in the final scale. Note that although one item (“you can’t really change how addicted you are”) uses a pronoun that may be perceived self-referent, it is intended to refer to people in general. Given that this item did not stand out for non-smokers vs. smokers in qualitative or quantitative responses, it is very likely that the “you” was interpreted as “people in general” as intended.