Assessment of Bioanalytical Method Validation Data Utilizing Heteroscedastic Seven-Point Linear Calibration Curves by...

Bioanalytical methods developed in accredited forensic toxicology laboratories need to be validated according to the ISO/IEC 17025 standards to demonstrate that a method is fit for the intended use. The evaluation of the validation data can be a time-consuming process without a streamlined procedure on a common platform or the aid of a specific software package. The objective of this work was to develop a Microsoft (MS) Excel (Redmond, WA, USA) template, which can rapidly generate all the required numerical and statistical validation results of a quantitative bioanalytical assay with minimal data entry and to provide documented traceability of the validation data directly to the instrument raw data. Evaluation of method validation data can be done easily by taking advantage of the power of statistical tools available within Excel. The three key features of the template were the development of six pertinent weighted linear calibration models, the variance in instrument response as a function of concentration and integrated one-way analysis-of-variance (ANOVA) tables. None of the ANOVA tables in this template need to be recreated whenever the source data changes, which is a major time savings when a method contains several dozen analytes. It takes ∼60 minutes per analyte to enter all the instrument raw data manually from the chromatograms. The final method validation results are summarized in a two-page validation summary report, whereas the associated data tables and graphs are presented in an additional 65 pages of digital information, which can be saved for electronic records using portable document format (PDF). This EZSTATSG1.xltm customized MS Excel method validation template and a completed PDF example are being provided as downloadable files in the Supplementary data link to offer an option to the scientific community for expediting the evaluation of validation data.