Table 1 Evidence-based experimental approaches on LA intervention

Randomized control trial

Ideal experimental design providing the most reliable evidence

Requires huge amount of effort

Risk of inflicting ethical issues

A/B testing

Useful to compare impact of different types of interventions on the same objective

Requires certain effort in designing and implementation

May raise concerns on ethical issue

Comparison with previous implementation

A natural way to compare impact of interventions as most courses tend to repeat with similar instructional settings. This approach has minimal ethical concern

Delayed result

Test subjects (students) are different

Difficult to preserve the same setting and environment between implementations

Quasi-experiment

Easy to implement and evaluate by comparing pre and post intervention. No ethical concern

The result is not as reliable as RCT

Switching replications design

An adaptation of Quasi-experiment. Compare results of 2 groups applying the same intervention switching role of experimental and control group

Students’ attitude may already have changed by the time of switching the intervention