The development of conceptually sound and reliable health measures for children and adolescents is of critical importance for policy makers, researchers, clinicians, and families, as well as community leaders and the general public. Child and adolescent health measures can be used to assess the effects of disease or injury on health; to identify vulnerable children in clinical practices and vulnerable population subgroups in health plans or geographic regions; to measure the effects of medical care, policy, and social programs; and to set targets for improving health care (Szilagyi and Schor, 1998). Health measures also can identify general health trends over time to highlight areas of progress as well as emerging areas of concern.
Until the middle of the 20th century, data on infant and child mortality provided a reasonable assessment of child health (Guyer et al., 2000). The neonatal segment of infant mortality (number of infant deaths at less than 28 days per 1,000 live births) provided a window on conditions related to fetal development, complications of pregnancy and delivery, and the newborn period; the postneonatal segment helped in understanding conditions influencing child health through the preschool years (Black et al., 2003; Heron et al., 2010).
The middle of the 20th century saw a decrease in the influence of infectious diseases on child health. A different pattern of morbidity emerged, termed the “new morbidity” (Haggerty et al., 1993; Palfrey, 2006). The conditions dominating child health today often reflect behavioral and de-