Psychometric evaluation of the UTAUT scale using the graded response model

Abstract

This study examined the reliability and validity of the Unified Theory of Acceptance and Use of Technology (UTAUT) measurement instrument. The sample included 202 mathematics teachers randomly selected from national secondary schools in Malaysia. The dataset was analyzed using the MIRT (Multidimensional Item Response Theory) and LTM (Latent Trait Models) packages in R software. The psychometric properties of the UTAUT scale were assessed using the graded response model (GRM), a type of Item Response Theory (IRT) model. The findings indicate that the scale effectively differentiates between various levels of technological acceptance, with most items showing high discrimination values. The threshold parameters suggest that higher response categories correspond to greater levels of agreement. The scale provides the highest accuracy in the middle range of traits but is less precise at the lower and upper extremes. However, the UTAUT scale still demonstrates good model fit and reliability.