Three items measure how responsive a website's customer service is — including willingness to address customer needs, genuine interest in solving problems, and prompt handling of inquiries. One of four eTailQ subscales.
Wolfinbarger, M., & Gilly, M. C. (2003). eTailQ: Dimensionalizing, measuring and predicting eTail quality. Journal of Retailing, 79(3), 183–198.
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