Advancements in technology have brought far-reaching impacts to educational delivery. The use of technologies has become essential in a broad range of pedagogical activities and promoted the development of new modes of education. Hybrid learning and teaching is a mode of education which has benefited from the advancement of information and communications technologies. It refers to an instructional approach combining face-to-face and online instruction ^[1][2][1,2]. As reviewed by Wong et al. [3], there has been an increasing trend in the amount of work on hybrid learning and teaching over the past decade. Particularly, during the worldwide COVID-19 pandemic, the lockdowns and social distancing imposed by governments to control the epidemic resulted in the suspension of traditional face-to-face classes in educational institutions. In response to this tremendous impact, hybrid learning and teaching have been widely adopted as a substitution for the face-to-face approach. Such a sudden shift in the mode of educational delivery has also contributed to the rapid development of this emerging learning and teaching mode.

There has also been a range of work investigating hybrid learning and teaching. For example, Mourtzis et al. [4] developed a hybrid teaching model and examined its effectiveness in facilitating the launch of collaborative projects in a university. Elkhatat and Al-Muhtaseb [5] implemented a hybrid, flipped learning model and analysed how it affected the learning outcomes of students in a chemical engineering programme. Li et al. [6] also created a hybrid learning model and examined its use to address the challenges resulting from the pandemic. Al-Ataby [7] examined the effectiveness of using the learning management system ‘Canvas’ to support hybrid learning in a group of university students. Alsharif et al. [8] explored the effectiveness of using WhatsApp to support hybrid learning among a group of undergraduate medical students. Other examples include Makhachashvili and Semenist [9], Pham and Pham [10], Gamage et al. [11], and Lorenzo-Lledo et al. [12], whose research foci have been primarily upon students’ perceptions of, experience in, and satisfaction with hybrid teaching.

Hybrid learning and teaching feature the utilisation of technologies to engage students in a variety of learning environments in order to respond to their diverse learning preferences and enhance their learning experiences [1]. This approach, according to Gao ^[13][17], is often characterised by a combination of “online + offline” and “in-class + extra-curricular” activities. Linder [1] discussed different features of hybrid instruction, which include its similarities to different instruction modes that provide custom-made learning activities for different student groups, increased active learning in class through the flipped model and student engagement, and improved self-regulated and self-directed learning skills. Marchisio et al. ^[14][18] described hybrid learning and teaching in a higher education context as having “its simplicity, high flexibility, facilitation of students’ time management, fulfilment of learning needs, and giving additional value to face-to-face attendance” (p. 16). Miller et al. ^[15][19] further describe hybrid learning and teaching as encompassing such features as allowing students to choose how they want to attend a class session, providing equivalent class activities in all modes of delivery, using the same learning materials for all students, helping students master technological skills to take part in class activities with different delivery modes, and administering authentic assessments.

Various benefits to student learning have been reported for a class using the hybrid mode. They include, for example, catering to learner diversity, increasing student engagement, persistence, and retention, fostering student autonomy and independence, improving student learning performance, increasing students’ access to courses and resources, increasing learning flexibility, and maximising students’ social presence ^[16][17][13,20].

Hybrid learning and teaching over the years have been implemented in different disciplines such as nursing education, business education, science education, second language learning, and medicine education ^{[17][18][19][20][21][22]}[20,21,22,23,24,25]. The existing body of work on hybrid instruction has focused on several major areas.

One of the focuses concerns the development and implementation of hybrid learning and teaching models, methods, and activities ^{[4][5][6][7][8][23][24][25][26]}[4,5,6,7,8,26,27,28,29]. Ochia ^[23][26] developed and applied a hybrid teaching method in an undergraduate biomechanics course and reflected that its application can reduce human contact, maintain course goals, enrich students’ learning experiences, and increase their engagement with the course. Rodriguez-Paz et al. ^[24][27] designed and carried out a hybrid teaching model in an engineering course and found that the model is effective in motivating students and improving their performance based on a high passing rate of students taking the course.

Another focus is on students’ perceptions of, experience in, and satisfaction with hybrid learning and teaching ^[9][10][11][9,10,11]. Pham and Pham [10] investigated students’ perceptions of hybrid learning and teaching implementation in a Vietnamese college. They reported that a majority of students were well prepared for the use of technology for hybrid learning and teaching, while some encountered technical and communication issues. Gamage et al. [11] analysed students’ experience in hybrid learning and teaching and noted that even though the students were exposed to a synchronous and asynchronous learning environment and felt comfortable receiving education in this setting, they were still reluctant to engage themselves in learning.

One focus of the studies lies in the identification of challenges that students have in hybrid learning and teaching ^[12][27][12,30]. Lorenzo-Lledo et al. [12] examined the difficulties that university students faced during their transition period from traditional face-to-face teaching to hybrid instruction and identified challenges such as decreasing students’ learning motivation, increasing their feeling of loneliness, experiencing technical problems, and limiting engagement with teachers and peers. Tian ^[27][30] reported a case study of teaching a hybrid computer programming course and observed that staying focused during a lecture, balancing personal wants and personal needs, and keeping pace with live lectures are the major challenges.

The issue of sustainability in relation to hybrid learning and teaching has also been examined ^[28][29][30][31,32,33]. In their study, Compton et al. ^[28][31] found that a majority of students preferred the continuation of hybrid learning and teaching as an option after the COVID-19 pandemic. They raised that the flexibility of having this option connects closely with UNESCO’s sustainable development goal of inclusive and equitable quality education. Pucciarelli and Kaplan ^[29][32] analysed the challenges and opportunities of the hybrid teaching approach and illustrated the transition to this approach as a way towards more sustainable and responsible education. Griffin et al. ^[30][33] described the design and implementation of hybrid teaching environments and highlighted how sustainability was addressed in such an initiative, in aspects such as relevant technology solutions and inter-institutional co-operations. These studies show the potential and benefits of sustainable hybrid learning and teaching practices.

Evaluating hybrid learning and teaching is important for assisting education practitioners in making informed decisions on its planning and implementation in terms, for example, of types of students to be provided for hybrid instruction, course components, course material design, and assessments. The existing literature in relation to this research area has focused primarily on investigating factors influencing the effectiveness of hybrid learning and teaching ^[31][32][34,35]. For instance, Liu ^[31][34] identified factors affecting the effectiveness of hybrid classes, such as course objectives, students’ learning motivation, pedagogies, and technological resources, hardware, and software. Raes et al. ^[16][13], in their meta-analysis of 47 studies on hybrid learning and teaching, found that most of the literature is exploratory and qualitative in nature and has focused mainly on technological design, organisational implementation, and student experiences. They emphasised the need for more empirical investigations into diverse groups of participants. Similarly, Howell ^[33][36] also identified gaps in hybrid learning and teaching research that more evaluation studies are needed based on the results of its implementation, in particular, on the need for academic staff for professional development and additional support. In this regard, despite there being plenty of work done for the sake of student learning, scant attention has been paid to how academic staff evaluate the effectiveness of their hybrid teaching practices ^[34][14].

The evaluation of hybrid learning and teaching needs to address the contextual factors of implementation. For example, as a pedagogical approach involving the extensive use of technology, the technological development of a region and an educational institution has been identified by Rodriguez ^[35][15] as a factor influencing the effectiveness of implementation. In the Hong Kong context, which features a well-developed technological infrastructure, Li and Wong ^[36][16] showed that members of the academic community possess an overall high level of digital literacy. However, studies related to hybrid learning and teaching in Hong Kong have addressed only the student perspective of learning in specific subject disciplines, such as law [37], leadership education [38], and business [39]. There is a need to have a more comprehensive study of the feedback of academic staff on this instruction mode.