## 4 Discussion and Conclusions
While secondary identification techniques are those that allow candidates to be discarded, i.e., they do not \"tell\" if the AM and PM materials correspond to the same person, but rather if they are not compatible and, therefore, do not correspond to the same person.). In practical terms, this massive validation would proceed under the hypothesis that the skull is like a fingerprint, which, in case this hypothesis is empirically validated, would serve to give more validity to CFS as evidence in a court of justice. * CR already is a primary identification technique. The main task to be carried out would be the automation and integration of all stages of the CR process:
* Automatic analysis and segmentation of any type of skeletal structure in any type of image, radiographs or CT scans. * Automatic location and classification of morphological patterns on radiographs and CT scans that can help with identification. * Automatic superimposition of AM and PM materials, regardless of whether they are radiographs, 3D surface models and/or CT scans. * Lastly, the development of a decision support system able to aggregate as much information as possible to help the forensic expert in the decision-making process. * In relation to BP, there is also a real need (and urgent need in many cases (For instance, the age estimation of living individuals, that could be related to cases of pedophilia in pictures or videos, or the determination of the legal age in cases unaccompanied minor migrants.)) to incorporate tools that facilitate BP estimation. * The usual methodology in FA is generally limited in effectiveness. Many of these methods use very subjective criteria and, in many cases, have not been properly validated [223]. Some of the most commonly used BP methods were developed 50-100 years ago, as [PERSON]'s ten-phase method to analyze the public symphysis to estimate age [235], the Greulich and Pyle method based on the atlas [26] from the late fifties, and that of [PERSON] [79], developed in 1975. These were elaborated with a limited number of examples (a few hundred), normally biased by a common ancestry, and a limited age range compared to modern populations. In addition, the phases/patterns were observed and documented by one or a few researchers (based on their experience, knowledge and ability to recognize patterns), and a large group of methods is based on a series of linear measurements directly taken from the bone with the caliber or on radiographic images. From this point of view, it is necessary to develop identification methods with a higher degree of certainty and
discriminant capability, which ensure compliance with scientific standards and, consequently, their admissibility as expert evidence. * Despite the publication of new and more sophisticated methods for BP estimation, these are not integrated into the usual practice of FA. Such daily practice is almost exclusively based on the use of manual measurement tools and spreadsheets, and thus practitioners usually perceive these new methods as more complex than traditional approaches. The use of specific software is thus limited to a small number of practitioners. The lack of tools and computer platforms that facilitate and integrate the use of more complex and effective methods causes anthropologists to continue using methods that are already obsolete, though easy to use. * In order to face the two former limitations, it is also essential to address the difficulty of obtaining appropriate data/case studies for the development and validation of BP methods. On the one hand, as already mentioned before, study samples are very scarce or difficult to achieve. We refer, for example, to skeletal human remains, access to corpses available for research, invasive clinical studies, etc. On the other hand, such samples must meet important requirements: absence of pathological conditions or trauma (main limitation in clinical studies), both sexes, age groups and different ancestries well represented, complete and reliable AM information from official records, etc.