We hypothesize that local prediction models, suffering from small sample sizes, can benefit from integrating similar information from external sites. The project will provide methodology based on weighting of similar data from external sites in a prediction model for a target site. We will investigate different strategies for quantifying similarity, including 1) propensity score-based approaches, 2) similarity quantified parametrically as well as nonparametrically via the difference between the conditional empirical distribution of the outcome given the covariates per site, and 3) a deep learning approach. Besides empirical evaluation, we will provide comprehensive mathematical theory on the parameter estimates of corresponding regression models.
Institute of Medical Biometry and Statistics,
Faculty of Medicine and Medical Center –
University of Freiburg