Study flow chart. TABLE, Target Blood pressure LEvels in CKD Study; NEPHRO-SUN, Nephrology of Second University of Naples Study; RECORD-IT, REport of COmorbidities in non-Dialysis Renal Disease Population in Italy; SIR-SIN, Studio Italiano indicatori di Risultato multipli – epidemiologia dell'insufficienza renale cronica in Italia della Società Italiana di Nefrologia; ABP-CKD, Ambulatory Blood Pressure Study in Chronic Kidney Disease; NEPHRO-FEDERICO II, Nephrology of Federico II University of Naples Study.