Despite the universality of this logic, systematic reviews (maps and syntheses) are much better known in health research and for answering questions of the effectiveness of interventions (what works). We should not really need to use the term ‘systematic’ as it should be assumed that researchers are using and reporting systematic methods in all of their research, whether primary or secondary. We use transparent rigorous approaches to undertake primary research, and so we should do the same in bringing together studies to describe what has been studied (a research map) or to integrate the findings of the different studies to answer a research question (a research synthesis). The logic of systematic reviews is very simple.
