title: Tracking immunization: new twist on old concept.
mesh_terms: D002648:Child; D003120:Colorado; D006801:Humans; D017589:Immunization Programs / Q000706:statistics & numerical data*; D008484:Medicaid; D017057:Medically Uninsured; D010044:Outpatient Clinics, Hospital; D014481:United States; D014505:Urban Population