Data sources
In order to limit the review to current and highly relevant material inclusion criteria were established. Only full papers available in English relating to public health systems in developed countries were included, with OECD countries used to benchmark this criterion. A timeframe for inclusion of papers published in or after 2011 was established, as this aligns with significant national health reform within the country of residence of the research team (Australia). Papers not available in English were excluded from the study, as were title matches for which full papers were not available. Papers based in developing countries were excluded in order to align with the focus of this work on OECD countries. Papers reviewed in full which held no clear content relating to efficiency improvement in public health systems were also excluded. A range of text words, synonyms and subject headings were developed for the major concepts of health system, efficiency and improvement. These search terms were used to undertake searches of two electronic databases (PUBMED, MEDLINE) in February 2019. Search results were merged with duplicates removed, and screening was managed using Covidence.