Accuracy of scoring of the epiphyses at the knee joint (SKJ) for assessing legal adult age of 18 years

Abstract

Important aspects of forensic practice are age estimation and discrimination of individuals of unknown age as adults and minors. The developing knee joint was recognized as a potential site for age examination in late adolescence. We analyzed a sample of anteroposterior x-rays of the knee joints from 446 living individuals from Umbria, Italy (234 males and 212 females), aged between 12 and 26 years. We evaluated the ossification of the distal femoral (DF), proximal tibial (PT), and proximal fibular (PF) epiphyses. We took into account possible persistence of the epiphyseal scars in the ossified epiphyses by the adopted stages of those previously introduced by Cameriere et al. (2012). We also used measurements from all three epiphyses to calculate the total score of maturation for the knee joint (SKJ). Cohen Kappa coefficients of intrarater agreement for staging the DF, PT, and PF epiphyses were 0.839, 0.894, and 0.907, while interrater agreement was 0.919, 0.791, and 0.907, respectively. The resulting receiver operating characteristic (ROC) curves of SKJ show better discriminatory power than those for DF, PT, and PF epiphyses in predicting that the participant, either male or female, was an adult or a minor. The areas under the curves for SKJ were 0.991 and 0.968 vs. 0.944, 0.962, 0.974 and 0.891, 0.910, 0.918 for males and females, respectively. The results of the 2 by 2 contingency tables showed that SKJ score of 4 in males and SKJ score of 5 in females were the most suitable cut-off value in discriminating between adults and minors. Principally, the sensitivity test for males was 0.94, with 95 % confidence interval (95 % CI) 0.90 to 0.97 and specificity was 0.96 (95 % CI 0.91 to 0.98). The proportion of correctly classified individuals was 0.95 (95 % CI 0.91 to 0.97). For females, the sensitivity test was 0.89 (95 % CI 0.84 to 0.92) and specificity was 0.92 (95 % CI 0.87 to 0.96), the proportion of correctly classified individuals was 0.90 (95 % CI 0.85 to 0.94). These results indicate that the SKJ method may give valuable supporting information in forensic procedures for discriminating individuals of legal adult age of 18 years. Further studies should address the usefulness of the SKJ method in different populations.

Validation of third molar maturity index (I 3M ) for discrimination of juvenile/adult status in South Indian population

“…Age estimation of individuals requires a multidisciplinary approach and predicting individual's attainment of the age of majority is of primary importance in many cases [1][2][3] . The age of majority is the age at which the law considers someone reached adulthood and proclaimed to be a full legal citizen who further doesn't require supervision of a parent or guardian in decision making 4,5 .…”

The Use of Roche, Wainer, and Thissen's Skeletal Maturity of the Knee

“…Skeletal maturation at the knee, whether scored radiographically or using MRI, has recently become a tool for assessing whether individuals are over or under a legal age threshold . Such assessments are important in determining whether asylum seekers are under an age threshold that entitles them to asylum.…”

“…KEYWORDS: forensic science, forensic anthropology, age estimation from skeleton, knee joint, Bayes theorem, radiography, age threshold Skeletal maturation at the knee, whether scored radiographically or using MRI, has recently become a tool for assessing whether individuals are over or under a legal age threshold (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11). Such assessments are important in determining whether asylum seekers are under an age threshold that entitles them to asylum.…”

“…This method was developed using the Fels longitudinal growth study . Of the eleven cited studies of the knee, only two mention the RWT study, and this is only in passing within the introduction or discussion sections. This general absence may be because the method is over 40 years old, and as such, there may have been considerable secular trend since the publication in 1975.…”

“…First, the sample's age range ends at age 18 years. This means that in dealing with the 18‐year legal threshold, which has been the focus for three of the knee studies , the RWT study requires extrapolation beyond the actual sample's age distribution. There is the additional problem that the RWT sample may not match the socioeconomic status, activity pattern, or population specificity of a particular forensic case.…”