This document discusses outlier detection and modeling approaches for estimating maternal mortality rates. It outlines detecting and removing outliers by examining residuals from regression models, relationships between outcomes and covariates, and summary maternal mortality measures. It then discusses using spatial-temporal regression to capture systematic variation not explained by linear models, by running local regressions on residuals from the first stage weighted by geographic, time, and age proximity. This allows smoothing residual differences over countries and time to improve predictions.