The best source for finding a chart for interpreting laboratory values is the reference range chart printed on the individual patient's lab report, according to Lab Tests Online. Other options include the Merck Manual and Marshall University School of Medicine, notes the respective official websites.
Most laboratories have reference ranges that are slightly different from each other and are specific to the individual lab, states Lab Tests Online. This is because laboratories use different types of equipment and methods for performing the tests. A patient's lab report typically lists the lab's reference range next to each result so patients can determine whether their values fall within the normal range.