RT Book, Section A1 Hoppe, Jordana E. A1 Snyder, Robert A1 Accurso, Frank J. A1 Siparsky, Georgette A2 Hay, Jr., William W. A2 Levin, Myron J. A2 Deterding, Robin R. A2 Abzug, Mark J. SR Print(0) ID 1153318608 T1 Chemistry & Hematology Reference Intervals T2 Current Diagnosis & Treatment: Pediatrics, 24e YR 2018 FD 2018 PB McGraw-Hill Education PP New York, NY SN 9781259862908 LK accessmedicine.mhmedical.com/content.aspx?aid=1153318608 RD 2022/05/24 AB Laboratory tests provide valuable information necessary to evaluate a patient’s condition and to monitor recommended treatment. Chemistry and hematology test results are compared with those of healthy individuals or those undergoing similar therapeutic treatment to determine clinical status and progress. In the past, the term normal ranges relayed some ambiguity because statistically, the term normal also implied a specific (Gaussian or normal) distribution and epidemiologically it implied the state of the majority, which is not necessarily the desirable or targeted population. This is most apparent in cholesterol levels, where values greater than 200 mg/dL are common, but not desirable. Use of the term reference range or reference interval is therefore recommended by the International Federation of Clinical Chemistry (IFCC) and the Clinical and Laboratory Standards Institute (CLSI) to indicate that the values relate to a reference population and clinical condition.