Effectively engaging the private sector through vouchers and contracting - A case for analysing health governance and context.

Health systems of low and middle income countries in the Asia Pacific have been described as mixed, where public and private sector operate in parallel. Gaps in the provision of primary health care (PHC) services have been picked up by the private sector and led to its growth; as can an enabling regulatory environment. The question whether governments should purchase services from the private sector to address gaps in service provision has been fiercely debated. This purposive review draws evidence from systematic reviews, and additional published and grey literature, for input into a policy brief on purchasing PHC-services from the private sector for underserved areas in the Asia Pacific region. Additional published and grey literature on vouchers and contracting as mechanisms to engage the private sector was used to supplement the conclusions from systematic reviews. We analysed the literature through a policy lens, or alternatively, a 'bottom-up' approach which incorporates components of a realist review. Evidence indicates that both vouchers and contracting can improve health service outcomes in underserved areas. These outcomes however are strongly influenced by (1) contextual factors, such as roles and functions attributable to a shared set of key actors (2) the type of delivered services and community demand (3) design of the intervention, notably provider autonomy and trust (4) governance capacity and provision of stewardship. Examining the experience of vouchers and contracting to expand health services through engagement with private sector providers in the Asia Pacific found positive effects with regards to access and utilisation of health services, but more importantly, highlighted the significance of contextual factors, appropriate selection of mechanism for services provided, and governance arrangements and stewardship capacity. In fact, for governments seeking to engage the private sector, analysis of context and capacities are potentially a more useful frame than generalizable outcomes of effectiveness.