samples by the eligibility for the study and the number of losses in the cohort, the failure to provide sufficient information with which the representativeness of the sample can be assessed, and the failure to use appropriate controls (McCormick, 1997). In addition, the outcomes being assessed may be too limited. Finally, even for the outcomes selected, many studies fail to incorporate a specific underlying pathogenic or conceptual model to identify potential factors influencing the relationship between the initial state (i.e., prematurity or low birth weight) and the outcomes observed (McCormick, 1997).

There is a wide range of health and neurodevelopmental outcomes for infants born preterm, and many resources are required to provide the necessary medical, neurodevelopmental and educational support for the children and support for their families. More outcomes data are reported by birth weight categories than by gestational age categories, but until better measures of organ maturation are available, information regarding gestational age is necessary for medical decision making and parent counseling when a preterm delivery is anticipated. Because of their long-term impact, health care providers should focus not on preterm birth but on degree of organ maturity at birth and on short and long-term neurodevelopmental, functional, and health outcomes. Just as the etiologies of preterm birth are multifactorial, the neurodevelopmental, functional, and health outcomes of infants born preterm are determined by interactions among the genome, intrauterine environment, high-risk obstetric and neonatal intensive care provided, the home environment, and available community resources. Future research to develop better predictors of outcomes should focus on the relationships between brain structural and functional development, areas of the brain typically affected by brain insult and corresponding neurodevelopmental and behavioral deficits, and how organ recovery and plasticity occur. Better predictors of outcomes will allow for improved parent counseling, enhance safety of trials of maternal and infant interventions by providing more immediate feedback, and facilitate planning for use of comprehensive follow-up and early intervention resources. Until preterm birth can be prevented, much work also needs to be done to develop treatment strategies that prevent injury to the brain and other organs and support the infant’s ongoing development.