Investigating the combined effects of role assignment and discussion timing in a blended learning environment

Asynchronous online discussion (AOD) is an essential component of blended learning, and role assignment and timing are two important discussion design considerations. With the purpose of improving blended learning through effective AOD design, this study conducted a two-level factorial experiment to explore the main effects and interaction effects of role assignment and timing on blended learning outcome and experiences. In addition, this experiment examined the influence of role assignment and timing on participants' social communication in AOD and the effects of timing on individual role performance in role-based discussion. A total of 114 participants in a blended course were randomly assigned to four experimental conditions: role-based pre-class discussion (n = 29), role-free pre-class discussion (n = 29), role-based post-class discussion (n = 28), and role-free post-class discussion (n = 28). The results showed that the role assignment strategy featured by initiator, supporter, and arguer has led to improved learning experiences in terms of affection, sense of community, and forum experiences, as well as enhanced social communication in AOD; while timing affected the enactment, contribution, and participation of assigned roles in role-based discussions. However, there was no significant interaction between the two AOD strategies. In general, role-based post-class AOD is recommended after face-to-face lesson because of the better learning experience and role performance.