3.1 Introduction and purpose of this guidance

Methodological development for quantitative systematic reviews of effects has broad scientific consensus, however the same cannot be said across the field qualitative synthesis. In qualitative synthesis, the normative features ascribed to systematic reviews of quantitative data have been challenged, adopted, rejected, or transposed to different extents into analogous concepts and methods more attune to the nuances of the critical and interpretive research paradigms.

The purpose of this chapter is to provide the rationale, methodology and methods for meta aggregation as an approach to qualitative synthesis. Its developmental history is grounded in philosophic perspectives with the needs and expectations of evidence to inform health care decision-making. Meta aggregation is a method that mirrors the accepted conventions for systematic review whilst holding to the traditions and requirements of qualitative research (it aggregates findings in to a combined whole that is more than the sum of the individual findings in a way that is analogous with meta analysis).