Purposive program placement and the estimation of family planning program effects in Tanzania

Most studies evaluating the impact of family planning on fertility treat the presence of family planning clinics as being "randomly" assigned among the areas included in the study. They tend to ignore the possibility that the distribution of services may be related to the fertility level observed ina particular area. In some cases the distribution of services may respond to a conscious effort by public authorities or funding agencies to target areas with observed higher fertility. Even in absence of program planning, the factors determining service placement might be related to the determinants of high, or low,fertility in a particular area. If that is the case, and one fails to account for the endogeneity of family planning services, then the estimated impact of family planning programs will be biased. This article presents a modeling approach to address this issue. The model extends the simultaneous equation framework by integrating an individual-level model of timing and spacing of children with the dynamic process of program placement. Individual-level data from the 1991/1992 Tanzania Demographic and Health Survey are augmented with data on the timing or and factors influencing, family planning service placement to demonstrate the approach. The empirical results show that standard methods yield misleading results on the impact of different components of the family planning program on fertility. In particular, the effect of access to family planning hospitals on births is overstated, and the impact of access to health centers that offer family planning is understated significantly. We quantify the size of these effects through simulations.