A comparison of software for the evaluation of complex DNA profiles. (May 2019)

• Record Type: Journal Article
• Authors: You, Yupei; Balding, David
• Is Part Of: Forensic science international. Volume 40(2019)
• Page Start: 114
• Page End: 119
• Publication Date: 2019-05
• Subjects: DNA profile -- Low template -- Weight of evidence -- Software validation; Forensic genetics -- Periodicals; Génétique légale -- Périodiques; Forensic genetics; Electronic journals; Periodicals; 614.1
• DOI: 10.1016/j.fsigen.2019.02.014
• Languages: English
• ISSNs: 1872-4973

Abstract

Highlights: We compared two software in computing LRs for complex DNA profiles. Overall results from likeTLD and EuroForMix were similar. LikeLTD returned slightly better result than EuroForMix but required longer runtime. Dropin models were necessary for likeLTD and EuroForMix. Double- and Over-Stutter models in likeLTD provided a small advantage. Abstract: We compare two open-source programs for the evaluation of evidential weight arising from complex DNA profiles recovered in a crime investigation. Here, "complex" means one or more of: low-template, degraded and mixed-source. Although software for complex DNA profile analysis has made great strides in recent years, the ability of courts to effectively scrutinise and challenge the reliability of the resulting evidence remains problematic. One key step is to compare different software on the same evidence, but there are currently few published comparisons in part because of the problems posed by restricted access to commercial software. We present here an extensive comparison between two open-source software, LikeLTD and EuroForMix. We find that despite different modelling assumptions the two programs generate similar results. The differences that we do identify can inform future improvements and can provide a benchmark for acceptable discrepancies between alternative programs.