Inclusion Criteria:  Patient entered in SCREAM between 2012 and 2018 With two consecutive plasma-creatinine test(s) indicating an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m^2 With at least one eligible Hb after eGFR < 60 mL/min/1.73 m^2. The date of the first eligible Hb test is the study entry point/index date of the study.  Exclusion Criteria:  Patient who has had a recent pregnancy or childbirth (issued diagnosis within 2 years prior to index date). Patient with ongoing/recent cancer (diagnosed within the previous 3 years), haematological diseases or leukaemia. Patient with chronic infections (hepatitis, tuberculosis, or human immunodeficiency virus [HIV]); note by definition chronic infections are chronic and look back period will be to 1997. Patients with anemia at baseline (index date), defined by an anemia diagnosis in the year prior, a baseline Hb value within the anemia range according to the WHO definition, or the presence of a recent dispensation of ESA or iron (up to six months prior). Patient referred to nephrologist within the previous 2 years from cohort entry/ index date.