The institution-based prospective inception cohort study: design, implementation, and quality assurance in pediatric thrombosis and stroke research.

The development of well-designed cohort studies in rare diseases can lead to the discovery of new risk factors and prognostic markers, enhance understanding of natural history and outcomes, and provide preliminary data for randomized controlled trials of treatment strategies. Designing a robust cohort requires substantial upfront design and planning. Ideally, a cohort study of diseased individuals follows patients prospectively from the time of diagnosis (i.e., from the disease's inception). The objective of this article is to discuss the design and implementation of an institution-based prospective inception cohort study, with applied examples in pediatric stroke and thrombosis. Furthermore, we will discuss the ongoing management and quality assurance mechanisms necessary to optimize such a study. Although the resources necessary to implement a prospective inception cohort study are large, this approach can provide critical observational evidence on natural history and prognostic factors. Following multicenter validation, its findings can inform the design and execution of much-needed randomized controlled clinical trials. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.