Table 1.

Scale items related to measuring perceived persuasiveness, the measurement scale used for each item, and the number of measurement points.

References	Number	Scale items	Scale measurement	Points
Anagnostopoulou et al. (2017)		The [System] would	Strongly disagree to strongly agree	7
	1	Influence me
	2	be convincing
	3	be personally relevant for me
	4	make me [target behavior]
Thomas et al. (2017)	5	Motivational	Not very motivating to very motivating	5
	6	Appropriateness	Very inappropriate to very appropriate
	7	Effectiveness	Very ineffective to very effective
	8	Convincing	Very unconvincing to very convincing
Busch et al. (2016)	9	I find this feature useful	Strongly disagree to strongly agree	7
	10	I enjoy using this feature
		This feature would
	11	make me more aware of [policy]
	12	have a positive influence on my attitude toward [policy]
	13	lead me to comply with [policy].
Oduor and Oinas-Kukkonen (2017)		The system provides	Strongly disagree to strongly agree	7
	14	trustworthy content
	15	believable content
	16	accurate content
	17	professional information
Chang et al. (2018)		On average, [communications] are	Strongly disagree to strongly agree	5
	18	persuasive
	19	compelling
	20	logical
	21	plausible
Zhao et al. (2011)		[Communication] that is	Strongly disagree to strongly agree	5
	22	believable
	23	convincing
	24	important to me
Orji (2014); Orji et al. (2014)		The system would	Strongly disagree to strongly agree	7
	25	influence me
	26	be convincing
	27	be personally relevant for me
	28	make me reconsider my [behavior]
Zhang et al. (2014)		[Communications] were	Strongly disagree to strongly agree	7
	29	convincing
	30	persuasive
	31	strong
	32	good
	33	trustworthy
	34	reliable
Kaptein et al. (2009)a		Susceptibility authority:	Totally disagree to Totally agree	7
	35	I always follow advice from my general practitioner.
	36	When a professor tells me something I tend to believe it is true.
		Susceptibility consensus:
	37	If someone from my social network notifies me about a good book, I tend to read it.
	38	When I am in a new situation I look at others to see what I should do.
		Susceptibility liking:
	39	I accept advice from my social network.
	40	When I like someone, I am more inclined to believe him or her.
Busch et al. (2013)	41	Before I do something, I want to know how other people have done it, so I can feel more safe.	Fully agree to Fully disagree	9
	42	It is important to me to know what other people are doing.
	43	I trust information better where the source is specified.
	44	It is important for me to be precisely informed about things that I need to do, before I do them.
Hammer et al. (2016)	45	[Communications were]	Not polite to Very polite Not persuasive at all to Very persuasive	7
Hossain and Saini (2014)	46	The [communication] is	Truthful to Not truthful Unbelievable to Believable Not deceptive to Deceptive	8
	47	The [communicator] is	Sincere to Insincere Honest to Dishonest Not manipulative to Manipulative Not pushy to Pushy
Meschtscherjakov et al. (2016)		This system	Completely disagree to completely agree	7
	48	makes people change their behavior
	49	has the potential to influence people
	50	gives the behavior of its users a new direction
	51	is exactly what I need to change my attitude
	52	does not cause a change in behavior with me
	53	causes me to do some things differently
	54	Thanks to the system I reach my goals.
	55	I will use this system as often as possible.
	56	With the help of the system, I will behave differently in the future.
Koch and Zerbac (2013)	57	I had the feeling that [communicator] wanted to convince the reader of [communicator]'s standpoint	I do not agree at all to I fully agree	5
	58	[Communicator] wanted to convince me of [communicator]'s views
MacKenzie and Lutz (1989)	59	Attitude: The [communicator/communication] is	Good to bad Pleasant to Unpleasant Favorable to Unfavorable	7
	60	Credibility: The [communicator/communication] is	Convincing to Unconvincing Believable to Unbelievable Biased to Unbiased

^aThis is a sample. They also present items related to the susceptibility to the other Cialdini principles.