Table 1 Databases searched

Databases

Medline, CINAHL, MIDIRS, DARE, EMBASE, OVID, PubMed, ProQuest, Informit Science Direct, Cochrane Library, NHSEED

Published between 1994 and 2018

English language publications only

Article contained key search words or combined search terms: midwifery, midwife-led units, nurse-midwifery, birth centers, cost, cost-effectiveness, economic evaluation, economic outcomes, pregnancy risk classification, maternal outcomes, neonatal outcomes, clinical outcomes, maternity services

Primary research article or Systematic Review/Meta-analysis or Integrative Review

Economic analysis secondary to RCT accepted

Peer-Reviewed Journals

Population sample of childbearing women and/or their babies where risk classification profile defined and/or includes woman with high risk or complex pregnancy

Measurement of at least one economic outcome measure combined with clinical and/or other outcome measures, in midwifery care units or integrated midwifery continuity models that included antenatal, birthing and postnatal services, compared to other maternity service models

Economic perspective is funder/health service