Determination of reference ranges for elements in human scalp hair

Expected values, reference ranges, or reference limits are necessary to enable clinicians to apply analytical chemical data in the delivery of health care. Determination of references ranges is not straightforward in terms of either selecting a reference population or performing statistical analysis. In light of logistical, scientific, and economic obstacles, it is understandable that clinical laboratories often combine approaches in developing health associated reference values. A laboratory may choose to:Validate either reference ranges of other laboratories or published data from clinical research or both, through comparison of patients test data.Base the laboratory’s reference values on statistical analysis of results from specimens assayed by the clinical reference laboratory itself.Adopt standards or recommendations of regulatory agencies and governmental bodies.Initiate population studies to validate transferred reference ranges or to determine them anew.