Twenty-one nine-point items measure overall website service quality by adapting the five SERVQUAL dimensions—reliability, responsiveness, assurance, empathy, and tangibles—for an online retail context. The scale is based on the performance component of the SERVQUAL instrument, rephrased to apply to websites, and treats all items as a single summated scale rather than five separate subscales. Given its multidimensional content, its unidimensionality has been noted as a limitation.
Harris, L. C., & Goode, M. M. H. (2004). The four levels of loyalty and the pivotal role of trust: A study of online service dynamics. Journal of Retailing, 80(2), 139–158.
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