The concept of life satisfaction across cultures: An IRT analysis

The present study examined measurement equivalence of the Satisfaction with Life Scale between American and Chinese samples using multigroup Structural Equation Modeling (SEM), Multiple indicator multiple cause model (MIMIC), and Item Response Theory (IRT). Whereas SEM and MIMIC identified only one biased item across cultures, the IRT analysis revealed that four of the five items had differential item functioning. According to IRT, Chinese whose latent life satisfaction scores were quite high did not endorse items such as “So far I have gotten the important things I want in life” and “If I could live my life over, I would change almost nothing.” The IRT analysis also showed that even when the unbiased items were weighted more heavily than the biased items, the latent mean life satisfaction score of Chinese was substantially lower than that of Americans. The differences among SEM, MIMIC, and IRT are discussed.