Changing definitions of long-term follow-up: Should "long term" be even longer?

There have been amazing changes in outcomes of preterm (PT) infants in the past decades. Whereas early studies reported only survival rates, Dr. Julius Hess published the first outcome study of PT infants in Chicago in 1953. Dr. Lubchenco then published the 10-year follow-up of premature infants born in 1947-1953 and identified a 68% handicap rate. As a result of these early studies, the importance of evaluating NICU graduates both for surveillance and as an outcome of trials was recognized. During the 1970s, there was a gradual expansion in the number of follow-up programs in the United States (US) with an increasing number of follow-up studies published. In the 1980s, the importance of multicenter clinical research networks was recognized and the NICHD Neonatal Research Network (NRN) was initiated in 1986. Follow-up protocols, definitions, and outcomes have evolved over the last 30 years and will be reviewed with a focus on NICHD NRN studies.