choice of program components, in turn, must depend to a certain extent on the cost of inputs. For example, the relative abundance of labor in most developing countries may imply that decentralization of many health programs, and reliance on a large cadre of community-level health workers rather than a smaller cadre of more highly skilled health workers, is most cost-effective. Where labor is relatively expensive, it may be most cost-effective to centralize certain program components. Input prices are integral to the chuice of program content.

A major advantage of an economic model for Safe Motherhood is that it incorporates medical, biological, epidemiological, social and behavioral information, as well as cost data, into a methodology that is able to consider not only single interventions but an intervention package organiized into a unit of service. There are several possible model formulations, a few of which are discussed below.

The simplest and most often used approach consists of a single equation which relates inputs to a single output. This production function is combined with information about input costs to form a second relationship known as a cost function. The cost function provides the answer to the question: for any given level of output, what is the least cost way of producing it, and what will it cost?

The difficulty of relating inputs to outputs in the context of Safe Motherhood derives from the complexity of related programs. In particular, it is difficult to define a production function when more than one type of output is being produced. For this reason, several more complex approaches can be considered. Among the possibilities are linear programming, input-output models, and various non-linear approaches. All these approaches have in common the ability to find a cost-minimizing optimum use of resources, and are discussed in more detail in the appendix to this report.

One difficulty with the use of optimization models at this stage is our lack of knowledge of the effectiveness of interventions, as discussed above. That is, we do not have a clear measure of the relationship between program inputs and outcomes. As a result, workshop participants concluded that it was more feasible to set goals in terms of services delivered rather than health outcomes, defining relationship between services and health outcomes on the basis of expert opinion.

At this stage, therefore, it would make sense to consider a limited number of program models applied to comparable population bases, each of which would adopt a different combination of activities and approaches, and to assess costs and effectiveness in a standardized manner. This common approach has been used to compare alternative health sector strategies in a variety of areas -- alternative vaccination strategies, for example. These can include routine services, routine services supplemented by campaigns, static or mobile services, and other types of delivery. In the context of Safe Motherhood, one could compare varying degrees of emphasis on community-based and referral services, for example.

This sort of typology approach has already received considerable attention from the 17