Mostad Petter, Tamsen Fredrik
Mathematical Sciences, Chalmers University of Technology, Gothenborg, Sweden.
Mathematical Sciences, Gothenburg University, Gothenburg, Sweden.
Int J Legal Med. 2019 Mar;133(2):613-623. doi: 10.1007/s00414-018-1916-3. Epub 2018 Sep 15.
During 2014-2015, Sweden received asylum applications from more than 240,000 people, of which more than 40,000 were termed unaccompanied minors. In a large number of cases, claims by asylum seekers of being below 18 years were not trusted by Swedish authorities. To handle the situation, the Swedish national board of forensic medicine (Rättsmedicinalverket, RMV) was assigned by the government to create a centralized system for medical age assessments. RMV introduced a procedure including two biological age indicators; x-ray of the third molars and magnetic resonance imaging of the distal femoral epiphysis. In 2017, a total of 9617 males and 337 females were subjected to this procedure. No validation study for the procedure was however published, and the observed number of cases with different maturity combinations in teeth and femur were unexpected given the claims originally made by RMV. We present a general stochastic model enabling us to study which combinations of age indicator model parameters and age population profiles are consistent with the observed 2017 data for males. We find that, contrary to some RMV claims, maturity of the femur, as observed by RMV, appears on average well before maturity of teeth. According to our estimates, approximately 15% of the tested males were children. These children had an approximate 33% risk of being classified as adults. The corresponding risk for an adult to be misclassified as a child was approximately 7%. We determine uncertainties and ranges of estimates under reasonable perturbations of the prior.
2014年至2015年期间，瑞典收到了超过24万份庇护申请，其中超过4万份来自无人陪伴的未成年人。在大量案例中，瑞典当局并不相信寻求庇护者声称自己未满18岁的说法。为应对这种情况，瑞典政府指定国家法医学委员会（Rättsmedicinalverket，RMV）创建一个集中的医学年龄评估系统。RMV引入了一个程序，包括两个生物年龄指标：第三磨牙的x光检查和股骨远端骨骺的磁共振成像。2017年，共有9617名男性和337名女性接受了该程序。然而，尚未发表对该程序的验证研究，而且考虑到RMV最初提出的说法，牙齿和股骨中不同成熟度组合的观察病例数出人意料。我们提出了一个通用的随机模型，使我们能够研究年龄指标模型参数和年龄人口概况的哪些组合与2017年男性的观察数据一致。我们发现，与RMV的一些说法相反，RMV观察到的股骨成熟度平均出现在牙齿成熟度之前。根据我们的估计，大约15%的受试男性是儿童。这些儿童被归类为成年人的风险约为33%。成年人被误分类为儿童的相应风险约为7%。我们确定了在先验合理扰动下估计的不确定性和范围。
