Government Social Research
Last Updated: 16/9/2008
REA methods for answering non-impact questions are less developed than for impact questions. This is largely because systematic reviews have focused on synthesising evidence from experimental and quasi-experimental research, and because there is a greater consensus on the hierarchy of available evidence on “what works?” (i.e. Randomised controlled trials at the top and simple before and after studies at the bottom).
REAs, however, are still suited to answering a range of other questions, which can be grouped as:
A useful tool to help formulate your question is the PICO acronym to think through the different areas you want to address in the REA. The acronym is used more commonly in impact questions but used flexibly can also help with other types of question. The acronym covers:
When using this for non-impact questions it is unlikely that all four areas will be relevant to the evidence that you want to collect. For example, if you were interested in finding out how an intervention worked your question may not need to include a comparison or control group. Instead, the ‘C’ in PICO directs the review towards contextual details.
Formulating the REA question index