This proposal is to request continued participation of UT Southwestern in the Cooperative Neonatal Network. With an expansion from 2 to 3 hospitals, our population will include approximately 22,500 births per year and 365 infants < 1500 g. The addition of the third hospital provides a primarily middle class, caucasian population which has been underrepresented in Network studies. Major strengths of our center demonstrated in the first 5 years include the ability to enroll large numbers of infants in the Network trials (the second greatest enrollment of the participating centers), timely data collection (with submission of major data forms in a shorter interval than in all but one small center), and the contributions of the PI and Co-PI (who have separately chaired 3 committees and drafted the protocol for the next major clinical trial slated for the Network). The PI as director of the Perinatal Epidemiology Program at UT Southwestern is particularly committed to clinical trials and has participated effectively in such demanding multi-center trials as the Infant Health and Development Program. The obstetric consultant is Director of the Maternal Fetal Medicine training program in an eminent Department of Obstetrics. The quality of the follow-up program and our ability to design and conduct major clinical trials is reflected our trial to determine whether primary follow-up care reduces the mortality of indigent very low birth weight risk infants after discharge from the nursery by 50% and total days of pediatric intensive care by 33% (sample size - 762 infants; approximately 250 enrolled to date). Based on our experience in the Network and participation in the editorial board of the National Perinatal Epidemiology Unit (Oxford, England) which has been extraordinarily successful in conducting multi-center perinatal trials at relatively low cost, we suggest a number of methods to augment the cost effectiveness of the Network. These include 1) careful assessment of the amount of generic data to collect; 2) consideration of factorial designs to answer more questions with greater clarity with the same number of patients 3) consideration of modified consent procedures when treatment risk is not increased above that experienced clinically and when parental comprehension is compromised during labor or the early neonatal period, and 4) in relatively uncomplicated trials, involvement of patients in nonuniversity hospitals to increase sample size and generalizability of results.