This article is presented as a guide to results and diagnostics within a STRmix report.
Until recently, forensic DNA profile interpretation was predominantly a manual, time-consuming process undertaken by analysts using heuristics to determine those genotype combinations that could reasonably explain a recovered profile. Probabilistic genotyping (PG) has now become commonplace in the interpretation of DNA profiling evidence. As the complexity of PG necessitates the use of algorithms and modern computing power, it has been dubbed by some critics as a “black box” approach. The current article discusses the wealth of information that is provided within the output of STRmix, one example of a continuous PG system. The authors discuss how this information can be evaluated by analysts either to give confidence in the results or to indicate that further interpretation may be warranted. Specifically, the authors discuss the “primary” and “secondary” diagnostic output by STRmix and give some context to the values that may be observed.