Three items measure the degree to which a consumer believes a product or service is free from effort and easy to use. Referred to as 'complexity' (reverse) by Meuter et al.
Meuter, M. L., Bitner, M. J., Ostrom, A. L., & Brown, S. W. (2005). Choosing among alternative service delivery modes: An investigation of customer trial of self-service technologies. Journal of Marketing, 69(2), 61–83.
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