The SCS-CE is the most widely used instrument for measuring consumer perceptions of celebrity endorser source credibility in advertising research. Ohanian (1990) operationalised Hovland, Janis, and Kelly's (1953) source credibility model for celebrity endorsement contexts, extending it to include physical attractiveness as a third credibility dimension beyond the original expertise-trustworthiness dyad. The Expertise dimension captures the perceived knowledge, experience, and competence of the celebrity in the product domain being endorsed — the degree to which the endorser is seen as a qualified, skilled, and expert source. Trustworthiness captures the perceived honesty, integrity, and believability of the endorser — the degree to which the celebrity is seen as credible, sincere, and dependable. Attractiveness captures the perceived physical appeal, style, and overall attractiveness of the celebrity — the degree to which the endorser is seen as physically and aesthetically appealing. All three dimensions are theoretically and empirically predictive of consumer attitude toward the advertisement, attitude toward the endorsed brand, and purchase intention, but through different mechanisms: expertise operates via argument quality and knowledge transfer; trustworthiness operates via source reliability and reduced scepticism; attractiveness operates via identification, liking, and aspirational association. Ohanian validated the scale across multiple celebrity endorsers and product categories using confirmatory factor analysis.
5-point semantic differential scale; 15 bipolar adjective pairs, 5 per dimension; dimensions averaged separately
Expertise (5 items): perceived knowledge, competence, and specialised experience of the celebrity in the endorsed product domain. 5-point semantic differential (1 = low-expertise pole, 5 = high-expertise pole). Items averaged.
Trustworthiness (5 items): perceived honesty, integrity, sincerity, and dependability of the celebrity as an information source. 5-point semantic differential. Items averaged.
Attractiveness (5 items): perceived physical appeal, style, and aesthetic attractiveness of the celebrity. 5-point semantic differential. Items averaged.
Full scale items shown. Always cite the original source when using this scale in research.
The three SCS-CE dimensions should be reported and tested separately; do not sum into a total source credibility score without theoretical justification. Expertise is the strongest predictor of purchase intention across most product categories (Ohanian, 1991, JA); trustworthiness is most important for reducing counter-argumentation; attractiveness is most important for image-based products and self-congruence effects. The scale is designed for evaluation of a specific celebrity-product pairing — different celebrity-product combinations will produce very different profiles. The scale is also applicable to non-celebrity spokespersons (expert endorsers, typical consumers, company executives) with minor wording adaptations.
Ohanian, R. (1990). Construction and validation of a scale to measure celebrity endorsers' perceived expertise, trustworthiness, and attractiveness. Journal of Advertising, 19(3), 39–52.
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