We previously developed a high-fidelity sequencing method that utilizes molecular barcodes called the non-overlapping integrated read sequencing system (NOIR-SS) . NOIR-SS is distinct from other methods that utilize molecular barcodes owing to its ability for absolute quantitation of cancer mutations. Since a substantial fraction (or majority) of barcode tags include PCR/sequencing errors, removal of erroneous barcode tags is crucial for absolute quantitation of cancer mutations. NOIR-SS removes erroneous barcode tags during data analysis.