Table 1 Key definitions used in search strategy

The systematic review aimed to identify studies that report on the cost-effectiveness of strategies to improve the utilization and/or provision of maternal and newborn health care in low-income and lower-middle-income countries. We define the key terms here:

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Cost-effectiveness measure:

reports a measure of cost per effect. Articles were eligible if they reported on the cost per health care interaction, per biomedical intervention received, per health gain, per life-saved (or death averted), per life-year saved (or years of life lost averted), per quality adjusted life-year (QALY) gained, or per disability-adjusted life-year (DALY) averted. The cost per effect measure was defined broadly, though it did need to refer to the population benefiting from maternal and newborn care. For example, strategies to deliver mosquito nets were included only if the cost-effectiveness measure reported on the effect on pregnant women or their newborns.

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Strategies:

one or more innovations, initiatives, approaches, or activities that aim to either i) influence health practices of individuals or communities or ii) improve health care provision by enhancing front-line worker capability and performance. Strategies may target the individual, community, front-line worker, organization or another aspect of the health system. Articles on biomedical interventions (e.g. prevention of mother-to-child transmission of HIV or administering misoprotosol) were eligible only if they contained one more activities that sought to directly change its demand or supply. For instance, an article on a new syphilis test would be eligible only if there were also activities to support its introduction, such as training frontline workers in how to prevent and manage syphilis in pregnant women.

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Maternal and newborn health (MNH) care:

an interaction that takes place between a front-line worker (of any cadre) and a woman, newborn or other family member during pregnancy, childbirth or in the 28 days following birth.

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Low-income countries (LICs) and lower-middle-income countries (LMICs):

countries with a gross domestic product (GDP) per capita of less than US $4036, as categorised by the World Bank in 2012. LICs have GDP per capita less than US $1026, and LMICs have a GDP per capita between US $1026 and US $4035. A list of eligible countries is provided in Additional file 2.