Meta-ethnography and policy effectiveness: an Evidential Pluralism perspective

Abstract Evidence-based policy is typically grounded in a narrow conception of evidence, one that prioritises comparative studies and quantitative meta-analyses as the preferred base for establishing causal claims. However, this prevailing theory of evidence—often implicitly adopted in policy contexts—faces serious limitations when it comes to capturing the complexity of social interventions, particularly in fields such as education. We argue that this narrow conception ignores the extensive volume of causal evidence that is generated in qualitative research fields such as meta-ethnography. Far from being epistemically inferior, we contend that meta-ethnographies could make an essential contribution to the evidential base for policy. By analysing meta-ethnography using the Evidential Pluralism framework (which scrutinises evidence of mechanisms alongside evidence of correlation), we show that meta-ethnographic studies can be fruitfully reinterpreted as providing evidence of a mechanism complex. This evidence can play a crucial role, as meta-ethnography can show how mechanisms enable, reinforce, or counteract a policy of interest. We illustrate this potential use of meta-ethnography with two examples, one from educational research (viz., a study of adolescent experiences of school belonging) and one from nursing studies (viz., a study of why some women continue smoking during pregnancy). While the article thus discusses these two fields in particular, we conclude by laying out the circumstances under which our results may generalise to other fields that make use of meta-ethnographies.