Nelson RG, Grams ME, Ballew SH, et al. - Researchers sought to develop assessment tools to distinguish individuals at increased risk of chronic kidney disease (CKD), characterized by reduced estimated glomerular filtration rate (eGFR). They performed individual-level data analysis of 34 multinational cohorts from the CKD Prognosis Consortium including 5,222,711 individuals from 28 countries. During a mean follow-up of 4.2 years, 660,856 incident cases (14.9%) of reduced eGFR occurred among 4,441,084 participants without diabetes (mean age, 54 years, 38% women). During a mean follow-up of 3.9 years, 313,646 incident cases (40%) occurred among 781 627 participants with diabetes (mean age, 62 years, 13% women). Age, sex, race/ethnicity, eGFR, history of cardiovascular disease, ever smoker, hypertension, body mass index, and albuminuria concentration were included in the equations for the 5-year risk of reduced eGFR. These equations demonstrated high discrimination and variable calibration in diverse populations. In 9 external cohorts consisting of 2,253,540 individuals, similar discrimination and calibration were identified.