Measures consumer perceptions of social media influencer credibility across four dimensions adapted from traditional source credibility research. Similarity is added as a fourth dimension because perceived similarity between the influencer and follower is a unique driver of parasocial relationships and persuasion in influencer marketing. Widely used in influencer marketing effectiveness research.
Likert (1–7, strongly disagree to strongly agree)
Trustworthiness — perceived honesty and sincerity of the influencer (Likert 1–7, strongly disagree to strongly agree)
Expertise — perceived knowledge and competence in the domain
Attractiveness — perceived physical and social appeal
Similarity — perceived similarity between influencer and follower
Full scale items shown. Always cite the original source when using this scale in research.
Four subscale scores. Trustworthiness and expertise are the strongest predictors of purchase intention via influencer endorsements. Similarity is particularly important for nano- and micro-influencers. Authenticity perceptions are increasingly important — consumers are sensitive to overly commercial influencer content.
Lou, C., & Yuan, S. (2019). Influencer marketing: How message value and credibility affect consumer trust of branded content on social media. Journal of Interactive Advertising, 19(1), 58–73.
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