How many response categories are sufficient for Likert type scales? An empirical study based on the Item Response Theory

The current study investigates the optimum number of response categories for Likert type scales under item theory (IRT). data was collected from university students attend to mainly faculty medicine and education. A form “Social Gender Equity Scale” developed by Gozutok et al. (2017) prepared, which had 3, 5 7-point categories. graded model (GRM) used calibrations. results have revealed that using a 5-point option provides advantages over 3-point category in terms reliability test information perspective scale development process. The-5 point also easier responding process respondents while it does not pose major disadvantage compared reliability. Therefore, based on findings study, researchers are recommended use their