DSP2 Dotaz Zobrazit nápovědu
Sex estimation methods based on skeletal remains vary on the selection of skeletal element, data acquisition and statistical approach resulting in variable classification accuracies that are highly dependent on the sample population. The only exception of this rule seems to be the os coxa, that appears to differ consistently between males and females across the globe. Currently sex estimation based on the os coxa can be easily estimated by taking ten measurements, inputting these in the DPS2 software and getting a sex estimate and the probability of correct group assessment. The performance of the software is highly reliable as confirmed by a validation study by Brůžek et al. (2017). Yet, there are still many populations not represented in the reference sample used to develop the software. The current study aimed to validate DPS2 using a sample from Crete, Greece. A total of 133 os coxae were measured following instructions on DSP2. Data were used to estimate sex with the software and to create population specific formulae for Greeks. DSP2 classified 117/133 (85.7%) of the sample with over 95% posterior probability (PP) of correct classification. Of the individuals classified with over 95% PP, only 3 were misclassified (2.6%).The best population specific formula only improved this percentage by 2.1% which indicates that DSP2 is a reliable tool for sex estimation in the Greek sample and it is recommended as method of choice in sex estimation of remains of unknown ancestry. If Greek ancestry is confirmed, population-specific formulae can be used in conjunction with DSP2 for a more reliable sex estimation.
- MeSH
- diskriminační analýza MeSH
- lidé MeSH
- pánevní kosti anatomie a histologie MeSH
- software * MeSH
- určení pohlaví podle kostry * MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
- Geografické názvy
- Řecko MeSH
Thanks to technical progress and the availability of virtual data, sex estimation methods as part of a biological profile are undergoing an inevitable evolution. Further reductions in subjectivity, but potentially also in measurement errors, can be brought by approaches that automate the extraction of variables. Such automatization also significantly accelerates and facilitates the specialist's work. The aim of this study is (1) to apply a previously proposed algorithm (Kuchař et al. 2021) to automatically extract 10 variables used for the DSP2 sex estimation method, and (2) to test the robustness of the new automatic approach in a current heterogeneous population. For the first aim, we used a sample of 240 3D scans of pelvic bones from the same individuals, which were measured manually for the DSP database. For the second aim a sample of 108 pelvic bones from the New Mexico Decedent Image Database was used. The results showed high agreement between automatic and manual measurements with rTEM below 5% for all dimensions except two. The accuracy of final sex estimates based on all 10 variables was excellent (error rate 0.3%). However, we observed a higher number of undetermined individuals in the Portuguese sample (25% of males) and the New Mexican sample (36.5% of females). In conclusion, the procedure for automatic dimension extraction was successfully applied both to a different type of data and to a heterogeneous population.
- MeSH
- algoritmy * MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- pánevní kosti * diagnostické zobrazování MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- soudní antropologie * metody MeSH
- určení pohlaví podle kostry * metody MeSH
- zobrazování trojrozměrné * MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Portugalsko MeSH
OBJECTIVES: A new tool for skeletal sex estimation based on measurements of the human os coxae is presented using skeletons from a metapopulation of identified adult individuals from twelve independent population samples. For reliable sex estimation, a posterior probability greater than 0.95 was considered to be the classification threshold: below this value, estimates are considered indeterminate. By providing free software, we aim to develop an even more disseminated method for sex estimation. MATERIALS AND METHODS: Ten metric variables collected from 2,040 ossa coxa of adult subjects of known sex were recorded between 1986 and 2002 (reference sample). To test both the validity and reliability, a target sample consisting of two series of adult ossa coxa of known sex (n = 623) was used. The DSP2 software (Diagnose Sexuelle Probabiliste v2) is based on Linear Discriminant Analysis, and the posterior probabilities are calculated using an R script. RESULTS: For the reference sample, any combination of four dimensions provides a correct sex estimate in at least 99% of cases. The percentage of individuals for whom sex can be estimated depends on the number of dimensions; for all ten variables it is higher than 90%. Those results are confirmed in the target sample. DISCUSSION: Our posterior probability threshold of 0.95 for sex estimate corresponds to the traditional sectioning point used in osteological studies. DSP2 software is replacing the former version that should not be used anymore. DSP2 is a robust and reliable technique for sexing adult os coxae, and is also user friendly.
