Does explicit teaching of critical thinking improve critical thinking skills of English language learners in higher education? A critical review of causal evidence

This paper presents the results of a systematic review of international studies to establish whether explicit teaching of critical thinking is effective in enhancing the critical thinking skills of English language learners in higher education and to identify the most promising approaches. A search of 12 electronic databases supplemented by other sources yielded more than 1794 studies. Only 36 met the pre-defined inclusion and exclusion criteria. A range of approaches were tested and almost all claimed to be effective, but only explicit instruction in general critical thinking skills was found to have the best evidence of effectiveness. However, because most of the studies were small-scale and/or methodologically flawed, the evidence is not strong enough to be conclusive. Evidence for the other approaches was even weaker. These findings suggest that research in this field is still rather immature and more large-scale, replicable robust studies are needed to advance the field.