Abstract:AIM: To evaluate the flipped classroom model for teaching horizontal strabismus didactics in an ophthalmology residency program in China as part of a visiting professorship from the United States. METHODS: Residents from an ophthalmology residency program in China were invited to participate in flipped classroom sessions taught by an experienced American ophthalmology faculty in 2018. Residents were instructed to watch a pre-class video lecture prior to the in-class-case-based activity. Content tests (5 Ophthalmic Knowledge Assessment Program style questions) and surveys were administered before and after the classroom sessions (100% response rate). These results were compared to that of an American cohort who were taught the same content. RESULTS: The Chinese cohort of 12 residents preferred the flipped classroom to the traditional classroom at higher rates than the American cohort of 40 residents (92% vs 55%, P=0.04) and felt that all ophthalmology topics would be appropriate for the flipped classroom teaching style (P-values between 0.008 and <0.001). In both Chinese and American cohorts, we found that the exotropia curriculum saw a small but significant improvement in performance following the flipped classroom session (P=0.025 for Chinese residents; P=0.001 for US residents), whereas scores in both groups for the esotropia course did not significantly improve. CONCLUSION: This is the first study to evaluate the flipped classroom model implemented by a visiting ophthalmology professor in a global outreach setting. The flipped classroom sessions are viewed favorably by the Chinese residents relative to the US cohort with a modest impact on knowledge. Decreased in-person interpreter requirement and increased student engagement make this model valuable in cross-cultural visiting professorship settings. Finally, the flipped classroom may lend itself well to a virtual format to prevent the transmission of COVID-19, although such a format requires further study.