Table 1 Instrument description of the concepts measured, scales, alternatives, and items examples

Private car habit

“Below, some activities are listed. Which travel mode are you most likely to use to reach these activities?”.

Going out for dinner

Car sharing, public transport, motorcycle, taxi, cycling, walking, other

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Transport for daily trips

“If you think about your daily travels (to work, to study, for grocery shopping, etc.), how often do you use the following transport modes, on average?”

Private car as a driver, private car as a passenger, car sharing, public transport, motorcycle, taxi, cycling and walking.

(5) Daily;

(4) 4–6 days/week;

(3) 1–3 days/week;

(2) Once/a few times a month;

(1) More seldom;

(0) Never

Attitudes

“My support for implementation of car sharing in society is …”

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1 = Very weak to 7 = Very strong

Environmental concern

“I believe that using the car causes many environmental problems”

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1 = Strongly agree to 7 = Strongly disagree

Personal norms

“I would feel good if I traveled more sustainably”

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1 = Strongly agree to 7 = Strongly disagree

Political orientation

“Political views are sometimes referred to as ‘left’ and ‘right’. Generally, where would you place your views on this scale?”

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1 = On the far left to 7 = On the far right

Green political scale

“Political issues are sometimes referred to in a green environmental scale. Where would you place yourself in such a green scale?”

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1 = Not green at all to 7 = Very green

Motives

“In your opinion, which of the following motives are incentives for you to use car sharing?”

M1 (the accessibility of car sharing parking lots near my place/workplace); M2 (to reduce expenses);

M3 (to travel more sustainably);

M4 (for more comfort when traveling);

M5 (the convenience of having a car only when I need it);

M6 (to avoid responsibilities with maintenance and repair of my own car);

M7 (to avoid looking for parking spots or other motives);

M8 (other)

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