Minimum Age Concept: Full of Pitfalls

The authors deserve recognition for describing the minimum age concept in the forensic age estimation of young refugees (1), because many experts ignore it. Many physicians infer majority only from the completed maturation of the bones of the hand (possible at 16.1 years, according to Schmeling) or wisdom tooth mineralization (possible at 17.3 years). Some even think that refugees themselves should prove that they are underage, which is wrong. The onus, instead, is on physicians and administrative bodies to prove that someone is over 18; if this cannot be done beyond a shadow of a doubt, the person should legally be considered a minor. But the minimum age concept itself has its pitfalls. It is based on the idea that the reference studies’ youngest participant represents the lower limit for a particular characteristic. The sample size in the relevant age range is often small. Schmeling’s example posits ossification stage 3a of the medial clavicular epiphysis. It uses a reference study by Wittschieber with only 24 male subjects (2). Fortunately for the young Somali being assessed, two of the subjects happened to be minors. Similarly, the oft-cited reference study by Kellinghaus is statistically deficient, given its small sample size in the critical age range (3). By contrast, a large study by Bassed (4) documented 17 year olds as having stage 5 ossification, the highest ossification stage—a finding that illustrates the absurdity of the research method if the intention is to use the minimum age concept. These results confirm a long-known fact: there is enormous variation in the chronological course of puberty as well as of bone and dental development. Physical maturity cannot be used to prove legal majority. For this reason, and also because of medico-ethical and legal considerations, genital and X-ray exams should not be performed without clear medical indication.