The main objective of this study is to explore birth nursing home data using treestructured regression. A nonparametrica pproacho f tree-structuredr egression method is implementedin to this data. This approachi s slightly differentf i'om widely used CART methodologyo f Breiman et al. (19E4,C lassificationa nd RegressioTn rees,C hapmana nd Hall, New York). Thed ffirencesb etweenth em are thosei n splilting rules and pruning strategy.C onventionasl plitting rules are replacedh y rules basedo n log-rank statisticsfo r two sarnplcd ata. Whereasn ew pruning strategiesa re also devised.F inal resulto f thiss tudyi s to developg roups af babiesb asedo n covariates. This studyr evealst hat birth wcighl existenceo f physiologicaml alfunctiond uring nursingh omea nd levelo f cducationo f molher determineg roups development,