Table 2.

Phenotyping and biomarker development

Key Messages	Current Challenges
• Simultaneous innovations in physiological, imaging-based, molecular, and genetic biomarker discovery have greatly improved patient care and facilitated the design of clinical trials using surrogate endpoints.	• Health disparities in the overall population related to age, race, sex, socioeconomic class, or geographical location complicate effective patient care and the recruitment of fully representative cohorts. Health disparities research might shed light on mechanisms to account for phenotypic and genetic variation in these populations.
• A common infrastructure for pediatric and adult RRDs could support bidirectional preclinical and clinical investigations, as well as mechanisms to screen for early markers of disease in otherwise asymptomatic patients.	• Despite the establishment of clinical networks, subcontracting and institutional review board agreements represent significant hurdles in conducting interinstitutional research. The formulation of widely adopted standard operating protocols, in addition to the use of centralized, multicenter processes, represents a promising approach.
• Detailed phenotypic analysis of common disease cohorts might reveal otherwise unknown rare diseases that provide translatable genetic and molecular insights.

Definition of abbreviation: RRD = rare respiratory disease.