title: A series of recommended tests when validating probabilistic DNA profile interpretation software.
abstract: There has been a recent push from many jurisdictions for the standardisation of forensic DNA interpretation methods. Current research is moving from threshold-based interpretation strategies towards continuous interpretation strategies. However laboratory uptake of software employing probabilistic models is slow. Some of this reluctance could be due to the perceived intimidating calculations to replicate the software answers and the lack of formal internal validation requirements for interpretation software. In this paper we describe a set of experiments which may be used to internally validate in part probabilistic interpretation software. These experiments included both single source and mixed profiles calculated with and without dropout and drop-in and studies to determine the reproducibility of the software with replicate analyses. We do this by way of example using three software packages: STRmix™, LRmix, and Lab Retriever. We outline and demonstrate the profile examples where the expected answer may be calculated and provide all calculations.
authors.affiliation: ESR, Private Bag 92021, Auckland 1142, New Zealand; University of Auckland, Department of Statistics, Private Bag 92019, Auckland 1142, New Zealand. Electronic address: Jo.bright@esr.cri.nz.
authors.forename: Jo-Anne
authors.initials: JA
authors.lastname: Bright
authors.affiliation: Principal Forensic Services Ltd, United Kingdom.
authors.forename: Ian W
authors.initials: IW
authors.lastname: Evett
authors.affiliation: Forensic Science South Australia, 21 Divett Place, SA 5000, Australia; School of Biological Sciences, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia.
authors.forename: Duncan
authors.initials: D
authors.lastname: Taylor
authors.affiliation: University of Auckland, Department of Statistics, Private Bag 92019, Auckland 1142, New Zealand.
authors.forename: James M
authors.initials: JM
authors.lastname: Curran
authors.affiliation: ESR, Private Bag 92021, Auckland 1142, New Zealand.
authors.forename: John
authors.initials: J
authors.lastname: Buckleton
mesh_terms: D004247:DNA / Q000235:genetics*; D053803:Forensic Genetics; D006801:Humans; D011336:Probability; D012984:Software
chemical_list: D004247:DNA
keywords: Continuous models; DNA interpretation; Forensic DNA; LRmix; Lab Retriever; STRmix™