Introduction
Students often choose online courses for flexibility and freedom. Research shows that team-based learning (TBL) effectively promotes active learning and long-term retention. Asynchronous TBL is a teaching and learning method that allows students to complete the three phases of TBL while accessing course materials, interacting with instructors, and interacting with peers all at different times and locations. This study aimed to compare asynchronous versus synchronous TBL in an online course, assessing effectiveness through student performance on readiness assessment tests and course evaluations. We also used a modified TBL Student Assessment Instrument (TBL-SAI) to measure accountability, TBL method preference, satisfaction, and group work.

Methods
Pharmacy students enrolled in the "Global Health for Pharmacists" course were invited to participate in the study. With informed consent, their readiness test scores and evaluations were collected anonymously. Asynchronous TBL was implemented in Fall 2021 and 2022, allowing students to complete TBL phases independently via Canvas® and InteDashboard®. The synchronous TBL, following a traditional model, was conducted in Spring 2022 and 2023 using Canvas® and Moodle® Learning Managements Systems. Surveys and course evaluations measured student responses, with a target of 30-45 participants per group of second- and third-year pharmacy students. Non-participation did not affect students' grades.

Results
Of 63 participants, 52% were in the asynchronous and 48% in the synchronous cohort, with similar demographics across both groups. Most students had not previously participated in online TBL, but those who had rated it positively. Interest in the topic was the main reason for course enrollment. No significant differences were found in student performance between TBL formats: asynchronous IRAT#1 averaged 83 and synchronous 80 (p=0.224); IRAT#2 averaged 83 (asynchronous) and 88 (synchronous) (p=0.070). TRAT scores were also similar between cohorts.

Conclusion
Student performance, experience, and feedback indicated no significant difference between asynchronous and synchronous TBL in an online course.