In reviewing all protocols but especially protocols involving children, IRBs should be particularly attentive to potential problems in achieving adequate numbers and classes of study participants and to the appropriate strategies for managing such problems. Such strategies may include modifications of classic clinical trial designs and innovative approaches to recruiting children and then retaining them throughout the course of the study. At the same time, reviewers of research protocol should be alert to the appropriateness of strategies for recruiting children, including payments to children or parents. This topic is discussed further in Chapter 6.
As mentioned earlier in this chapter, long-term studies are a particular challenge and a particular need for many serious pediatric medical conditions. Assessing the possible developmental effects of medical treatments or interventions may require extremely lengthy follow-up, well beyond what the immediate study outcomes appear to mandate. For example, the adverse sequelae associated with the use of cranial radiation to prevent central nervous system spread of leukemia in children did not become evident until many years following the introduction of this therapeutic approach (Cousens et al., 1988; Roman and Sperduto, 1995). Despite the success of radiation in the short term, the eventual recognition of late effects, including impaired intellectual function, profound neuroendocrine abnormalities, and second central nervous system malignancies, ultimately resulted in efforts to eliminate cranial radiation from among the options for the treatment of leukemia.
Many other conditions may require long-term follow-up in order to understand the physical, psychosocial, or economic consequences of the condition and its treatment. For example, very-low-birth-weight infants must be monitored at least until they reach school age to assess in detail the sequelae of prematurity and its treatment (Fazzi et al., 1997). Likewise, if one wants to test certain kinds of preventive interventions, then the study must follow study participants for at least as long as it is expected to take the target condition to develop naturally without treatment.
Studies of the effects of certain drugs in children may also require long-term follow-up that is not necessary for adults. Because of developmental changes in hepatic and renal function, children may experience positive or negative changes in response as they receive certain drugs over a long period. For children receiving drug therapy for a chronic condition, the need for long-term follow-up for both safety and efficacy is therefore obvious.