An item response theory analysis of Rosenberg Self-Esteem among older Korean adults

The Korean population is aging rapidly. An accurate measure of older adults' self-esteem, a psychological factor used to diagnose behavior and mental health, is becoming increasingly relevant. Previous studies have used the Rosenberg Self-Esteem Scale (RSES) to measure self-esteem, but most have conducted factor analysis based on the classic test theory. This study, in contrast, applied the item response theory to accurately test the validity and reliability of this measure of self-esteem among Korean older adults. The data used for analysis came from the Korean Welfare Panel Survey conducted in 2018, including 5,061 people aged 65 years or older. The analysis showed that item eight was a misfit, and items three, nine, and ten were challenging to answer. It was found that, as the response range, a 4-point Likert scale was appropriate, and most of the items between the old and young adults functioned differently. As a result, RSES is not suitable for use for the older Korean adults because it did not satisfy the construct validity. This analysis provides an academic basis for revising items of the Rosenberg Self-Esteem Scale to measure self-esteem in older Korean adults accurately.