Deriving national and disaggregated estimates for the demand for family planning satisfied indicator from contraceptive prevalence using household health surveys.

BACKGROUND: Demand for family planning satisfied (DFPS) is one of the core indicators for monitoring reproductive health. However, it involves a series of questions that are not always available in national health surveys, hindering the international comparability and tracking progress in those settings. This study updates an alternative method for calculating DFPS based on contraceptive prevalence (CPR) when direct estimation is not feasible. METHODS: Based on survey data from 1,099 subnational regions across 103 countries, we fitted least-squares regression models that predicts DFPS for both any contraceptive methods and modern methods. A fractional polynomial approach was employed to account for non-linear relationships. Model performance was assessed using a 5-fold cross-validation strategy, evaluating bias, mean absolute error and correlation. RESULTS: The models, using CPR and the difference between total and modern CPR as predictors, were able to explain over 97% of the variability of DFPS by any and modern contraceptives. Bias and the magnitude of the errors were around 0.1 in the cross-validated sample. Validating the results for other inequality dimensions beyond subnational region yielded even better metrics. CONCLUSIONS: The predicted estimates proved to be a good approximation for DFPS in circumstances where direct estimation is not possible. This study confirms that modeling DFPS through contraceptive prevalence remains valid and extends its applicability to DFPS based on modern methods. Furthermore, the estimates were robust for varying inequality dimensions, allowing equity analyses to be performed when appropriate.