In the second full paragraph in the left column on page 1476 in the 26 June 2018 issue, the descriptions of 2 assays as monoclonal or polyclonal were reversed. “Freelite (the Binding Site Group Ltd.) a monoclonal-based antisera vs N Latex FLC assay (Siemens Healthcare) a polyclonal-based antisera” should read “Freelite (The Binding Site Group Ltd.; a polyclonal antiserum–based assay) vs N Latex FLC assay (Siemens Healthcare; a monoclonal antiserum–based assay).” The error has been corrected in the published article.