Imbalanced Sex Ratios in Sex Estimation Using Probabilistic Sex Diagnosis (Diagnose Sexuelle Probabiliste [DSP]): Implications for Paleodemographic Interpretations - 2026
Imbalanced Sex Ratios in Sex Estimation Using Probabilistic Sex Diagnosis (Diagnose Sexuelle Probabiliste [DSP]): Implications for Paleodemographic Interpretations
palaeodemography; population analysis; populational sexual dimorphism; sexing; Archeology (arts and humanities); Anthropology; Archeology
Abstract :
[en] This study investigates biases in sex estimation using the DSP (Diagnose Sexuelle Probabiliste—Probabilistic Sex Diagnosis) method in bioarchaeological contexts. The aim is to assess whether this method overperforms in estimating one of the sexes and to explore the implications for palaeodemographic interpretations. A meta-analysis was conducted using data from 32 archaeological and current populations (n = 2303), spanning prehistoric to modern times. DSP-based sex estimations were compared with results from medical analytical, genetic, and alternative osteological methods. In the DSP reference data, morphological variability was analyzed through principal component analysis of pelvic measurements, and classification methods were evaluated using both linear discriminant analysis and random forest modeling. Findings reveal a consistent overestimation of female representation in sex ratios when using DSP, particularly in prehistoric and contemporary populations. This bias is linked to population-level differences in sexual dimorphism, especially in the IIMT and SPU pelvic dimensions. The proportion of indeterminate individuals—most often male—varied by population, with European samples showing more male indeterminates and North American samples showing more female indeterminates. The study confirms a systematic sex classification bias within DSP applications, driven by both statistical and morphological factors. These distortions can mislead interpretations of population structures, funerary practices, and mortality patterns. Corrective approaches, such as redistributing indeterminate individuals or calculating confidence intervals for sex ratios, are proposed. Further research into population-specific dimorphism and complementary methods is recommended to improve reliability in sex estimation for population-based studies.
Disciplines :
Archaeology
Author, co-author :
Bédécarrats, Samuel ; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France
Santos, Frédéric; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France
Galovičová, Tereza; Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague, Czech Republic
Blaizot, Frédérique; UMR 8164 HALMA, CNRS, Université de Lille, Inrap, Lille, France
Chenal, Fanny; Inrap Grand Est, Paris, France, UMR 7044 Archimède, CNRS, Université de Strasbourg, Université de Haute Alsace, Mulhouse, France
Deguilloux, Marie-France; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France
Gleize, Yves; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France ; Inrap Nouvelle-Aquitaine et Outre-mer, Bègles, France
Kacki, Sacha; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France ; Department of Archaeology, Durham University, Durham, United Kingdom
Pruvost, Mélanie; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France
Réveillas, Hélène; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France ; Service Archéologie Bordeaux Métropole, Bordeaux, France
Rottier, Stéphane; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France
Thomann, Aminte; Inrap Grand Ouest, Cesson-Sévigné, France ; UMR 6273 CRAHAM, CNRS, Unicaen, Caen, France
Thomas, Aline; UMR 7206 Eco-Anthropologie (EA), Muséum National d'Histoire Naturelle, CNRS, Université de Paris, Paris, France
Thomson, Ivy; Inrap Auvergne Rhône-Alpes, Clermont-Ferrand, France ; UMR 7264 CEPAM, CNRS, Université Côte d'Azur, Nice, France
Villotte, Sébastien ; Université de Liège - ULiège > Département des sciences historiques ; UMR 7206 Eco-Anthropologie (EA), Muséum National d'Histoire Naturelle, CNRS, Université de Paris, Paris, France ; Quaternary Environments & Humans, OD Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
Brůžek, Jaroslav; UMR 5199 PACEA, Université de Bordeaux, Bordeaux, France ; Department of Anthropology and Human Genetics, Faculty of Science, Charles University, Prague, Czech Republic
Imbalanced Sex Ratios in Sex Estimation Using Probabilistic Sex Diagnosis (Diagnose Sexuelle Probabiliste [DSP]): Implications for Paleodemographic Interpretations
We thank the French Agence Nationale de la Recherche (ANR) that funded WomenSOFar (grant number ANR\u201021\u2010 CE 03\u20100008). We also thank the ANR and German Research Fundation (DFG), which funded the Ancestra (grant number ANR\u201015\u2010 CE 27\u20100001) and Interact projects (grant numbers ANR\u201017\u2010FRAL\u20100010 and DFG\u2010HA\u20105407/4\u20101), which generated part of the data reused in this study. We also thank all the colleagues who agreed to make their raw data available for this meta\u2010analysis and Alastair Millar for editing the English manuscript. We dedicate this study to the late Jaroslav Br\u016F\u017Eek. We thank him for his involvement in the design, interpretation, and writing of this work and cherish the memory of how working with him has always been a pleasure. The authors did not use any Generative AI or AI\u2010assisted technology in the preparation of this work.
Austad, S. N., and K. E. Fischer. 2016. “Sex Differences in Lifespan.” Cell Metabolism 23, no. 6: 1022–1033. https://doi.org/10.1016/j.cmet.2016.05.019.
Blaizot, F. 2005. “Etude de l'Occupation Funéraire du Brézet.” In Le Brézet rue Georges Besse, Puy-de-Dôme, Rapport de Fouille Archéologique, par Gérard Vernet. Inrap, Service Régional de l'Archéologie Auvergne.
Boldsen, J. L., G. R. Milner, and S. D. Ousley. 2022. “Paleodemography: From Archaeology and Skeletal Age Estimation to Life in the Past.” American Journal of Biological Anthropology 178, no. S74: S74. https://doi.org/10.1002/ajpa.24462.
Brauer, G. 1988. “Osteometrie.” In Anthropologie. Handbuch des Vergleichenden Biologie des Menschen, Band 1, Par R. Knussmann, vol. 1. Gustav Fischer Verlag.
Braun, S., N. Schwendener, F. Kanz, S. Lösch, and M. Milella. 2023. “What We See Is What We Touch? Sex Estimation on the Pelvis in Virtual Anthropology.” International Journal of Legal Medicine 137, no. 6: 1839–1852. https://doi.org/10.1007/s00414-023-03034-w.
Brůžek, J. 2002. “A Method for Visual Determination of Sex, Using the Human Hip Bone.” American Journal of Physical Anthropology 117, no. 2: 157–168. https://doi.org/10.1002/ajpa.10012.
Brůžek, J., F. Santos, B. Dutailly, P. Murail, and E. Cunha. 2017. “Validation and Reliability of the Sex Estimation of the Human Os Coxae Using Freely Available DSP2 Software for Bioarchaeology and Forensic Anthropology.” American Journal of Physical Anthropology 164, no. 2: 440–449. https://doi.org/10.1002/ajpa.23282.
Brůžek, J., A. Schmitt, and P. Murail. 2005. “Identification Biologique Individuelle en Paléoanthropologie. Détermination du Sexe et Estimation de l'Âge au Décès à Partir du Squelette.” In Origine et Evolution Humaine, 217–246. Comité des Travaux Historiques et Scientifiques.
Case, A., and C. Paxson. 2005. “Sex Differences in Morbidity and Mortality.” Demography 42, no. 2: 189–214. https://doi.org/10.1353/dem.2005.0011.
Curtis, D. R., and J. Roosen. 2017. “The Sex-Selective Impact of the Black Death and Recurring Plagues in the Southern Netherlands, 1349–1450.” American Journal of Physical Anthropology 164, no. 2: 246–259. https://doi.org/10.1002/ajpa.23266.
Darwin, C. 1874. The Descent of Man, and Selection in Relation to Sex. John Murray.
De Almeida, S. M., M. V. D. De Carvalho, M. C. T. De Lyra Menezes, G. G. P. Petraki, E. Cunha, and E. P. Soriano. 2020. “Validation of the DSP2 Tool in a Contemporary Identified Skeletal Collection From Northeastern Brazil.” Advances in Anthropology 10, no. 2: 169–180. https://doi.org/10.4236/aa.2020.102010.
Dunsworth, H. M. 2020. “Expanding the Evolutionary Explanations for Sex Differences in the Human Skeleton.” Evolutionary Anthropology: Issues, News, and Reviews 29, no. 3: 108–116. https://doi.org/10.1002/evan.21834.
Féliu, C., P. Adam, G. Alberti, et al. 2017. “Obernai (Bas-Rhin). Parc d'Activités Économiques Intercommunal: 6000 Ans d'Histoire au Pied du Mont Sainte-Odile.” Report. Inrap. https://shs.hal.science/halshs-01767175.
Fernández-Crespo, T., and C. de-la-Rúa. 2016. “Demographic Differences Between Funerary Caves and Megalithic Graves of Northern Spanish Late Neolithic/Early Chalcolithic.” American Journal of Physical Anthropology 160, no. 2: 284–297. https://doi.org/10.1002/ajpa.22963.
Franklin, D. 2012. “Human Skeletal Remains From a Multiple Burial Associated With the Mutiny of the VOC Retourschip Batavia, 1629.” International Journal of Osteoarchaeology 22, no. 6: 740–748. https://doi.org/10.1002/oa.1235.
Gaillard, J. 1960. “Détermination Sexuelle d'Un os Coxal Fragmentaire.” Bulletins et Mémoires de la Société d'Anthropologie de Paris 1, no. 2: 255–267. https://doi.org/10.3406/bmsap.1960.1145.
Galeta, P., and J. Brůžek. 2020. “Chapter 4.2 - Sex Estimation Using Continuous Variables: Problems and Principles of Sex Classification in the Zone of Uncertainty.” In Statistics and Probability in Forensic Anthropology, edited by P. Z. Obertová, A. Stewart, and C. Cattaneo. Academic Press. https://doi.org/10.1016/B978-0-12-815764-0.00016-2.translate.
Galovičová, T. 2024. “Poloautomatický Přístup k Sekundární Pohlavní Diagnóze Rdss (Santos, 2021): Použitelnost v Archeologickém Souboru.” PhD thesis, Faculty of Science, Univerzita Karlova. https://dspace.cuni.cz/handle/20.500.11956/190286.
Goude, G. 2023. “WomenSOFar.” Carnet Hypothèses. https://womensofar.hypotheses.org/.
Haas, J., J. E. Buikstra, D. H. Ubelaker, and D. Aftandilian. 1994. Standards for Data Collection From Human Skeletal Remains: Proceedings of a Seminar at the Field Museum of Natural History, Organized by Jonathan Haas. Arkansas Archeological Survey.
Hager, L. D. 1989. “The Evolution of Sex Differences in the Hominid Bony Pelvis.” University of California. https://search.proquest.com/openview/ddeae57ffe2072afbbb733f12b84e9ff/1?pq-origsite=gscholar&cbl=18750&diss=y.
Hesketh, T., and Z. W. Xing. 2006. “Abnormal Sex Ratios in Human Populations: Causes and Consequences.” Proceedings of the National Academy of Sciences 103, no. 36: 13271–13275. https://doi.org/10.1073/pnas.0602203103.
Hollingshaus, M., R. Utz, R. Schacht, and K. R. Smith. 2019. “Sex Ratios and Life Tables: Historical Demography of the Age at Which Women Outnumber Men in Seven Countries, 1850–2016.” Historical Methods: A Journal of Quantitative and Interdisciplinary History 52, no. 4: 244–253. https://doi.org/10.1080/01615440.2019.1605863.
Jerković, I., Ž. Bašić, I. Kružić, and Š. Anđelinović. 2018. “Creating Reference Data on Sex for Ancient Populations Using the Probabilistic Sex Diagnosis Method: A Validation Test Using the Results of aDNA Analysis.” Journal of Archaeological Science 94: 44–50. https://doi.org/10.1016/j.jas.2018.04.007.
Klales, A. R. 2020. Sex Estimation of the Human Skeleton: History, Methods, and Emerging Techniques. Academic Press.
Kuchař, M., A. P. Kotěrová, A. Morávek, et al. 2024. “Automatic Variable Extraction From 3D Coxal Bone Models for Sex Estimation Using the DSP2 Method.” International Journal of Legal Medicine 138, no. 6: 2647–2658. https://doi.org/10.1007/s00414-024-03301-4.
Le Roy, M. 2015. “Les Enfants au Néolithique: Du Contexte Funéraire à l'Interprétation Socioculturelle en France de 5700 à 2100 Avant J.-C.” Phd thesis, Université de Bordeaux. https://theses.hal.science/tel-01229878.
Lefranc, P., F. Bachellerie, F. Chenal, et al. 2018. “La Nécropole Néolithique Moyen d'Obernai “Neuen Brunnen” (Bas-Rhin): Rites Funéraires de la Première Moitié du 5e Millénaire Dans le sud de la Plaine du Rhin Supérieur (Grossgartach, Planig-Friedberg, Roessen).” Société Archéologique de l'Est/Université de Bourgogne 67: 5–57.
Lefranc, P., H. Réveillas, and Y. Thomas. 2015. “Les Pratiques Mortuaires du Néolithique Récent en Alsace (Nord-Est de la France): l'Exemple du Site de Gougenheim.” In Death as Archaeology of Transition: Thoughts and Materials: Papers From the 2nd International Conference of Transition Archaeology: Death Archaeology, Evora, Portugal, 29 April-1st May 2013, edited by L. Rocha, P. Bueno-Raminez, and G. Branco, vol. 2708. BAR International.
Lesciotto, K. M., and A. R. Klales. 2024. “Sex Estimation Using Metrics of the Innominate: A Test of the DSP2 Method.” Journal of Forensic Sciences 70, no. 1: 249–257. https://doi.org/10.1111/1556-4029.15645.
Li, H., J. Yi, and J. Zhang. 2011. “Estimating the Effect of the One-Child Policy on the Sex Ratio Imbalance in China: Identification Based on the Difference-in-Differences.” Demography 48, no. 4: 1535–1557. https://doi.org/10.1007/s13524-011-0055-y.
Lopes, A. R., E. de Oliveira, M. L. Silva, et al. 2024. “DSP2 for Sex Determination of Miscegenated Contemporary Hip Bones.” Anatomia, Histologia, Embryologia 53, no. 1: e12979. https://doi.org/10.1111/ahe.12979.
Machado, M. P., S. T. C. Salles, R. F. Alexandre, et al. 2018. “Application and Validation of Diagnose Sexuelle Probabiliste V2 Tool in a Miscegenated Population.” Forensic Science International 290, no. septembre: 351.e1–351.e5. https://doi.org/10.1016/j.forsciint.2018.06.043.
Marchal, F. 2003. “Le Dimorphisme Sexuel de Conformation de l'Os Coxal Humain. Bases Biologiques et Nouvelles Applications Possibles.” Bulletins et Mémoires de la Société d'Anthropologie de Paris 15, no. 1–2: 1–2. https://doi.org/10.4000/bmsap.552.
Mays, S. 1992. “Taphonomic Factors in a Human Skeletal Assemblage.” Circa 9, no. 2: 54–58.
Mestekova, S., J. Bruzek, J. Veleminska, and K. Chaumoitre. 2015. “A Test of the DSP Sexing Method on CT Images From a Modern French Sample.” Journal of Forensic Sciences 60, no. 5: 1295–1299. https://doi.org/10.1111/1556-4029.12817.
Murail, P., J. Brůžek, F. Houët, and E. Cunha. 2005. “DSP: A Tool for Probabilistic Sex Diagnosis Using Worldwide Variability in Hip-Bone Measurements.” Bulletins et Mémoires de la Société d'Anthropologie de Paris 17, no. 3–4: 167–176.
Orzack, S. H., J. W. Stubblefield, V. R. Akmaev, et al. 2015. “The Human Sex Ratio From Conception to Birth.” Proceedings of the National Academy of Sciences 112, no. 16: E2102–E2111. https://doi.org/10.1073/pnas.1416546112.
Parker, G. J., J. M. Yip, J. W. Eerkens, et al. 2019. “Sex Estimation Using Sexually Dimorphic Amelogenin Protein Fragments in Human Enamel.” Journal of Archaeological Science 101: 169–180. https://doi.org/10.1016/j.jas.2018.08.011.
Pedersen, F. A. 1991. “Secular Trends in Human Sex Ratios.” Human Nature 2, no. 3: 271–291. https://doi.org/10.1007/BF02692189.
Renkonen, K. O., O. Mäkelä, and R. Lehtovaara. 1962. “Factors Affecting the Human Sex Ratio.” Nature 194, no. 4825: 308–309. https://doi.org/10.1038/194308b0.
Rodriguez Paz, A., J. Banner, and C. Villa. 2019. “Validity of the Probabilistic Sex Diagnosis Method (DSP) on 3D CT-scans from Modern Danish Population.” La Revue de Médecine Légale 10, no. 2: 43–49. https://doi.org/10.1016/j.medleg.2018.08.002.
Ruff, C. 1998. “Evolution of the Hominid Hip.” In Primate Locomotion, edited by P. E. Strasser, J. G. Fleagle, A. L. Rosenberger, and H. M. McHenry. Springer US. https://doi.org/10.1007/978-1-4899-0092-0_23.
Saintot, S. 2015. Vertaizon, Puy-de-Dôme, Auvergne, La Roussille - Site Néolithique, Volume 1 - Texte, Annexes et Inventaires. Inrap.
Sánchez-Mejorada, G., J. Gómez-Valdés, P. Herrera, P. Veleminsky, and J. Bruzek. 2011. “Valoración del Método de Diagnóstico Sexual Probabilístico (DSP) en Una Colección Osteológica Mexicana.” Estudios de Antropología Biológica 15: 359–374. https://doi.org/10.22201/iia.14055066p.2011.42780.
San-Millán, M., V. Warrier, A. Carrera, and F. Reina. 2024. “Application of DSP2 for Biological Sex Estimation in a Spanish Sample: Analysis Based on Sex and Side.” International Journal of Legal Medicine 139: 847–862. https://doi.org/10.1007/s00414-024-03358-1.
Santos, F. 2021. “Rdss: An R Package to Facilitate the Use of Murail et al.'s (1999) Approach of Sex Estimation in Past Populations.” International Journal of Osteoarchaeology 31, no. 3: 382–392. https://doi.org/10.1002/oa.2957.
Schulter-Ellis, F. P., D. J. Schmidt, L. A. Hayek, and J. Craig. 1983. “Determination of Sex With a Discriminant Analysis of New Pelvic Bone Measurements: Part I.” Journal of Forensic Sciences 28, no. 1: 169–180.
Schultz, A. H. 1949. “Sex Differences in the Pelves of Primates.” American Journal of Physical Anthropology 7, no. 3: 401–423. https://doi.org/10.1002/ajpa.1330070307.
Sellier, P. 1996. “La Mise en Évidence d'Anomalies Démographiques et Leur Interprétation: Population, Recrutement et Pratiques Funéraires du Tumulus de Courtesoult.” In Nécropoles et Société au Premier Âge du Fer: Le Tumulus de Courtesoult (Haute-Saône), vol. 54, 136–142. Coll. Documents D'archéologie Française.
Skoglund, P., H. Malmström, M. Raghavan, et al. 2012. “Origins and Genetic Legacy of Neolithic Farmers and Hunter-Gatherers in Europe.” Science 336, no. 6080: 466–469. https://doi.org/10.1126/science.1216304.
Sorrentino, R., A. Pietrobelli, D. Mameli, T. Nicolosi, and M. G. Belcastro. 2025. “The Extent of the Hip Bone Sexual Dimorphism in Two Italian Coeval Modern Skeletal Samples.” Scientific Reports 15, no. 1: 2439. https://doi.org/10.1038/s41598-025-86197-3.
Stan, E., C.-O. Muresan, R. Dumache, et al. 2024. “Sex Estimation From Computed Tomography of Os Coxae—Validation of the Diagnose Sexuelle Probabiliste (DSP) Software in the Romanian Population.” Applied Sciences 14, no. 10: 4136. https://doi.org/10.3390/app14104136.
Thèves, C., E. Cabot, C. Bouakaze, P. Chevet, E. Crubézy, and P. Balaresque. 2016. “About 42% of 154 Remains From the “Battle of Le Mans”, France (1793) Belong to Women and Children: Morphological and Genetic Evidence.” Forensic Science International 262: 30–36. https://doi.org/10.1016/j.forsciint.2016.02.029.
Villotte, S., S. Kacki, and A. Thomas. 2024. “Sex Estimation of the Human Os Coxae in Archeological Contexts: An Advocacy of Using Both Diagnose Sexuelle Probabiliste and Brůžek's Morphoscopic Method.” International Journal of Osteoarchaeology 34, no. 5: e3334. https://doi.org/10.1002/oa.3334.
Vincenti, G., L. Molinaro, S. M. S. Sajjadi, H. Moradi, L. Pagani, and P. F. Fabbri. 2024. “Female Biased Adult Sex Ratio in the Bronze Age Cemetery of Shahr-i Sokhta (Iran) as an Indicator of Long Distance Trade and Matrilocality.” American Journal of Biological Anthropology 183, no. 4: e24911. https://doi.org/10.1002/ajpa.24911.
Waldron, T. 1987. “The Relative Survival of the Human Skeleton: Implications for Palaeopathology.” In Death, Decay and Reconstruction: Approaches to Archaeology and Forensic Science, edited by A. Boddington, A. N. Garland, and R. C. Janaway, 55–64. Manchester University Press.
Walker, P. L., J. R. Johnson, and P. M. Lambert. 1988. “Age and Sex Biases in the Preservation of Human Skeletal Remains.” American Journal of Physical Anthropology 76, no. 2: 183–188. https://doi.org/10.1002/ajpa.1330760206.
Wang, H., L. Dwyer-Lindgren, K. T. Lofgren, et al. 2012. “Age-Specific and Sex-Specific Mortality in 187 Countries, 1970–2010: A Systematic Analysis for the Global Burden of Disease Study 2010.” Lancet 380, no. 9859: 2071–2094. https://doi.org/10.1016/S0140-6736(12)61719-X.
Weiss, K. M. 1972. “On the Systematic Bias in Skeletal Sexing.” American Journal of Physical Anthropology 37, no. 2: 239–249. https://doi.org/10.1002/ajpa.1330370208.
Wood, B. A., and A. T. Chamberlain. 1986. “The Primate Pelvis: Allometry or Sexual Dimorphism?” Journal of Human Evolution 15, no. 4: 257–263. https://doi.org/10.1016/s0047-2484(86)80053-7.
