


We assessed feasibility, test-retest reliability, and convergent validity of the NIHTB-CB (measuring executive function, processing speed, memory, and language) by assessing 242 individuals with fragile X syndrome (FXS), Down syndrome (DS), and other ID, ages 6 through 25 years, with retesting completed after 1 month. advance the science of cognitive outcome measurement for individuals with intellectual disability (ID), we established administration guidelines and evaluated the psychometric properties of the NIH-Toolbox Cognitive Battery (NIHTB-CB) for use in clinical research. 2 From the University of California Davis Medical Center (R.H.S.) Human Development Graduate Group (R.H.S.), University of California Davis, Sacramento Feinberg School of Medicine (A.J.K., R.C.G.), Northwestern University, Chicago, IL MIND Institute and Department of Psychiatry and Behavioral Sciences (F.J.M., A.D., S.M.S., D.H.), University of California Davis Medical Center, Sacramento Morgridge College of Education (J.C., K.R.), University of Denver, CO Departments of Pediatrics (C.M., E.B.-K.) Neurological Sciences (E.B.-K.), and Biochemistry (E.B.-K.), Rush University Medical Center, Chicago, IL and Graduate School of Education (K.F.W.), University of California, Riverside.

1 From the University of California Davis Medical Center (R.H.S.) Human Development Graduate Group (R.H.S.), University of California Davis, Sacramento Feinberg School of Medicine (A.J.K., R.C.G.), Northwestern University, Chicago, IL MIND Institute and Department of Psychiatry and Behavioral Sciences (F.J.M., A.D., S.M.S., D.H.), University of California Davis Medical Center, Sacramento Morgridge College of Education (J.C., K.R.), University of Denver, CO Departments of Pediatrics (C.M., E.B.-K.) Neurological Sciences (E.B.-K.), and Biochemistry (E.B.-K.), Rush University Medical Center, Chicago, IL and Graduate School of Education (K.F.W.), University of California, Riverside.
