Factorize international mobility on academic performance: A time-varying DID method examining over 7million Chinese scholars

Objective International academic mobility of researchers provides them with access to global knowledge and innovation and shaping their research activities. This study seeks to examine the impact of international mobility on academic performance of researchers. Method We first visualized changes in researchers' academic performance before and after mobility. Then, we employed the Time-varying Difference-in-Differences (DID) model and Propensity Score Matching (PSM) methodology to uncover the impact of international mobility on researchers. Finally, we delved deeper into the relationship between international mobility patterns and academic performance. Results The visualized analysis results highlight substantial academic advancement in disciplines such as Biomedical and Life Sciences. Notably, researchers returning to China after mobility exhibit the most significant impact on academic performance, followed by those engaged in multiple movements ('circulation') across countries. In contrast, the 'emigration' group, not returning to China after mobility, exhibits the lowest impact on academic performance. Conclusions These results emphasize how international academic mobility significantly boosts researchers' academic performance. Particularly, researchers returning to China after mobility demonstrate the most substantial impact on academic performance. However, the noticeable surge in researchers leaving China presents a challenge in retaining their expertise. Therefore, it's crucial to promote active participation in international mobility while developing strategies to retain expertise post-mobility, which is vital for the scientific development of China.