A score method of constructing asymmetric confidence intervals for the mean of a rating scale item

This article presents a generalization of the Score method of constructing confidence intervals for the population proportion (E. B. Wilson, 1927) to the case of the population mean of a rating scale item. A simulation study was conducted to assess the properties of the Score confidence interval in relation to the traditional Wald (A. Wald, 1943) confidence interval under a variety of conditions, including sample size, number of response options, extremeness of the population mean, and kurtosis of the response distribution. The results of the simulation study indicated that the Score interval usually outperformed the Wald interval, suggesting that the Score interval is a viable method of constructing confidence intervals for the population mean of a rating scale item.