How accurate are modelled birth and pregnancy estimates? Comparison of four models using high resolution maternal health census data in southern Mozambique

Abstract

Background: Existence of inequalities in quality and access to healthcare services at subnational levels has been identified despite a decline in maternal and perinatal mortality rates at national levels, leading to the need to investigate such conditions using geographical analysis. The need to assess the accuracy of global demographic distribution datasets at all subnational levels arises from the current emphasis on subnational monitoring of maternal and perinatal health progress, by the new targets stated in the Sustainable Development Goals.

Methods: The analysis involved comparison of four models generated using Worldpop methods, incorporating region-specific input data, as measured through the Community Level Intervention for Pre-eclampsia (CLIP) project. Normalised root mean square error was used to determine and compare the models' prediction errors at different administrative unit levels.

Results: The models' prediction errors are lower at higher administrative unit levels. All datasets showed the same pattern for both the live birth and pregnancy estimates. The effect of improving spatial resolution and accuracy of input data was more prominent at higher administrative unit levels.

Conclusion: The validation successfully highlighted the impact of spatial resolution and accuracy of maternal and perinatal health data in modelling estimates of pregnancies and live births. There is a need for more data collection techniques that conduct comprehensive censuses like the CLIP project. It is also imperative for such projects to take advantage of the power of mapping tools at their disposal to fill the gaps in the availability of datasets for populated areas.

Keywords: comparison; demographic distribution; health geography; live births and pregnancies; maternal health census.

Figure 1

Study sites, Maputo and Gaza provinces in Southern Mozambique.

Figure 2

Data generation process for model comparison. CLIP, Community Level Intervention for Pre-eclampsia.

Figure 3

Data preparation process for validation. CLIP, Community Level Intervention for Pre-eclampsia.

Figure 4

Aggregated live births at admin 3 level.

Figure 5

Aggregated live births at admin 4 level.

Figure 6

Admin 3 level maps showing the residuals obtained from difference in estimated births between model 1 (CLIP only) and the other models. CLIP, Community Level Intervention for Pre-eclampsia.

Figure 7

Admin 4 level maps showing the residuals obtained from difference in estimated births between model 1 (CLIP only) and the other models. CLIP, Community Level Intervention for Pre-eclampsia.