Alternative Indexes for Monitoring Customer Perceptions of Service Quality: A Comparative Evaluation in a Retail Context

In 2 independent studies, the relative validity of various indexes that can be used to summarize consumers' service quality ratings are examined. In Study I, using typical commercial survey data from a fast-food/convenience retail chain, both the mean and top-box percentiles are found to be the best indicators of service quality, based on their correlation with customer-driven business performance measures. In Study II, the results are further confirmed by an extensive simulation that varies factors such as the shape of the underlying distribution of customer ratings and the strength of the relationship between customer ratings and business performance measures.