hematuria incidence/prevalence measurement percentage of study population with hydronephrosis developing hematuria during a period of time 2012-11-15T16:47:46Z CMO:0001205 The number of new cases of hematuria, that is blood in the urine, appearing in a study population with preexisting hydronephrosis, that is, dilation of the pelvis and calices of one or both kidneys because of the accumulation of urine resulting from obstruction to urine outflow, during a specified period compared to the total number of individuals in that study population, expressed as a percentage. clinical_measurement_ontology hematuria incidence in hydronephrosis jsmith