This FOA issued by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), the National Institute of Mental Health (NIMH), and the National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), encourages Research Project Grant (R01) applications from institutions/organizations that propose to develop, validate, and/or calibrate informative outcome measures for use in clinical trials for individuals with intellectual and developmental disabilities (IDD). This funding opportunity will address a significant need in the field, one that is especially apparent in efforts to develop pharmacological treatments for these populations. This solicitation will focus ongoing clinical and translational research on a neglected area essential for therapy and pharmacological treatment development. Potential applicants may be interested in FOA (PAR-11-038) “Preclinical Research on Model Organisms to Predict Treatment Outcomes for Disorders Associated with Intellectual and Developmental Disabilities (R01)” issued simultaneously with this FOA.