Ask Dr. Austin: Within normal limits (WNL)

The term “within normal limits” is often used by medical professionals when discussing findings for specific patients. It is a very useful expression and is often underused in medical writing. “Within normal limits” can describe physical exam findings, laboratory results, and medical images. The abbreviation “WNL” can reduce the word count when describing laboratory results in the Results section of an academic paper or in a case report form. For example; “All CBC, CMP, and LFT results were within normal limits (WNL) except the Hgb, which was 40. Chest X-ray and CT were also WNL.” As a medical writer, you want to make your writing clear and concise so that the reader can focus on the important points. The term “within normal limits” can help you accomplish this.