ately for infants (AAP et al., 2004). Physiologic differences also play a role; children have higher heart rates, and this may reflect itself in more rapid calcification of prosthetic valves, which affect the materials used in these products. Children also have different inspiratory flow rates and different abilities to coordinate manual tasks. For example, devices for inhaled administration of drugs need to accommodate timing the activation of an inhaler with the child’s intake of air. Lifestyle differences also play an important role for designing devices for children. For example, cochlear implants have been known to deprogram in response to contact with plastic playground slides (see Appendix F). Since children’s life spans are longer, devices that are left in place for long periods of time, such as cranio-facial prostheses, may show increased rates of polymer plate absorption. On the other hand, devices may need to be replaced more frequently as they wear out; growing children may require larger devices as they age (AAP et al., 2004).
A third reason to study this topic is that the evaluation of pediatric devices offers unique challenges. Similar to devices for use in adults, devices for use with children are subject to U.S. Food and Drug Administration (FDA) regulatory requirements. When FDA clearance or approval of a device requires clinical data, trials may provide important information on safety and efficacy. However, even the most rigorous trials have inherent limitations in terms of measuring long-term outcomes (especially in younger patients) and the ultimate generalizability of their findings. Given the small patient populations for many pediatric devices, premarket studies are often single-arm studies or registries as part of a Humanitarian Device Exemption (HDE) approval process, which may lead to increased uncertainty in terms of the knowledge gained. The incremental nature of the device innovation process and the inherent limitations of premarket studies argue for ongoing monitoring and evaluation of the outcomes in widespread clinical use. Ongoing evaluation is costly, however, and of particular concern in the realm of pediatric medical devices, where the markets are small and the economic incentives to innovate weak.
This paper explores these issues in pediatric devices, and, among the broad spectrum of devices that range from tongue blades to imaging machines, focuses specifically on the more technologically sophisticated end of the spectrum. It first reviews the main players in device innovation and the policy environment in which they operate. It then analyzes the dynamics of pediatric device innovation and evaluation, and the challenges inherent in designing and conducting premarket and postmarket clinical trials. The paper concludes with some observations about possible analytical, institutional, and economic solutions to improving the knowledge base about devices, while at the same time, fostering much needed innovation in this area.