The aim of our work is to describe the level of evidence supporting therapeutic recommendations in United States pancreatic adenocarcinoma guidelines, and its evolution over time. We recorded the level of evidence for each therapeutic recommendation extracted from the American Society of Clinical Oncology and National Comprehensive Cancer Network guidelines. In both United States guidelines, less than 9% of therapeutic recommendations are supported by a high level of evidence. In the National Comprehensive Cancer Network guidelines, there was no significant increase in high level of evidence recommendations over time. However, guidelines authors can only deal with the available evidence to develop recommendations while highlighting the strengths and weaknesses of included studies. There is a need for a more collaborative effort in pancreatic adenocarcinoma treatment to tackle important therapeutic questions and challenge the current framework of evidence. Cancer guidelines are ideally based on high levels of evidence (LOE). We aim to evaluate the LOE supporting recommendations in United States (US) guidelines on pancreatic adenocarcinoma (PDAC) treatment and its evolution over time. We searched for current guidelines from the American Society of Clinical Oncology (ASCO) and National Comprehensive Cancer Network (NCCN) and their prior publicly available versions on societies’ websites and/or MEDLINE. We recorded the LOE and class of recommendation (opinion of the writing panel) for each recommendation. We defined high LOE as: a “high” quality of evidence from the GRADE methodology (ASCO) and “Category 1” (NCCN). Our main outcome was the proportion of PDAC recommendations supported by high LOE. Proportions of high LOE recommendations were 5% (2/40) and 8% (12/153) in current ASCO and NCCN guidelines, respectively. Less than 10% of class I recommendations were based on high LOE. For NCCN guidelines, the proportion of high LOE recommendations did not improve over time and only three recommendations increased their LOE. We identified a small percentage of high LOE recommendations for PDAC treatment in US guidelines. However, guidelines authors can only deal with the available evidence. The current framework of evidence should be challenged with consideration of observational evidence. It shComprehensive guidelines are important tools on which any clinician or health care decision maker can rely to make daily treatment decisions . EvidencOur aim is to assess the LOE supporting recommendations in ASCO and NCCN guidelines in PDAC treatment, and its evolution over the years.We performed a systematic review to identify current US guidelines by the ASCO and the NCCN. Current guidelines were identified as the latest available version posted on each society’s website as of 10 October 2021 . Only publicly available (open access on society’s website) comprehensive guideline documents were included in this systematic review. Only guideline documents that included recommendations, including key points, organized by a type of classification of evidence clearly highlighted and separated from the rest of the text were included. Current guidelines were also reviewed to identify if there were any references to a previous iteration of the same guideline. We excluded expert consensus documents and provisional clinical opinions. Similarly, focused updates were not included because they were not representative of the evidence for the entire topic.We searched for (1) prior guideline documents archived and publicly available on societies’ websites , and if Guideline documents were downloaded, and all recommendations with a classification of evidence (level of evidence and class of recommendation) were abstracted by a single reviewer. Abstraction involved simple reporting and did not require judgment on the part of the abstractor. Recommendations were extracted from the main text and/or summary tables and/or algorithms if present. We used a standardized extraction form for extraction . TherapeThe classification of evidence is defined by a level of evidence and a class of recommendation. In the ASCO guidelines, the classification of evidence is defined by the level of evidence based on the GRADE methodology and a strength of recommendations  7,8,9,1,14,15,16− “high” quality of evidence from the GRADE methodology used in the ASCO guidelines (confidence that the true effect lies close to that of the estimate), and− “Category 1” from the NCCN guidelines (high-level evidence).Since both guidelines did not use the same classification of evidence, we defined high LOE as the following: For more details, see Each recommendation was also attributed a class of recommendation which synthetizes the opinion of the guideline writing panel regarding the risks and benefit based on the evidence and other factors. Based on the classification from the American College of Cardiology/American Heart Association Task force , we assiThe proportion of recommendations supported by high LOE in PDAC treatment for each current guideline.The proportion of current guideline recommendations supported by high LOE for each category of disease stage and treatment.The proportion of each class of recommendation supported by high LOE in current guidelines.The evolution of LOE over time for guidelines available with prior versions.Current ASCO and NCCN guidelines were published in 2016/2020 and 2021, respectively. Of note, the ASCO had published three documents for different disease stages, two in 2016 and one in 2020, that we considered as one comprehensive guideline in our work. A total of 51 and 189 recommendations were identified for ASCO and NCCN current guidelines, respectively . Proportions of therapeutic recommendations were 78% (40/51) and 81% (153/189) in the ASCO and NCCN guidelines, respectively . Other rThere were two and twelve therapeutic recommendations based on high LOE in the ASCO and NCCN guidelines, respectively . ProportRegarding disease stage, proportions of recommendations based on high LOE for “potentially curable disease” ranged from 10% (1/10) to 15% (4/27) between both guidelines A,C. PropRegarding treatment category, proportions of recommendations for “chemotherapy” based on high LOE ranged from 10% (1/10) to 16% (12/76) B,D. OnlyIn the ASCO guidelines, 27 and 13 therapeutic recommendations were classified as class I and II, respectively. A total of 7% (2/27) of class I therapeutic recommendations was based on high LOE. In the NCCN guidelines, 127 and 26 therapeutic recommendations were classified as class I and II, respectively. A total of 9% (12/127) of class I therapeutic recommendations was based on high LOE. There were no class III recommendations in neither ASCO nor NCCN guidelines.Only NCCN guidelines had prior publicly available versions of the whole comprehensive guideline, published in 2010 and 2017. There were 59 and 102 therapeutic recommendations in the 2010 and 2017 versions, respectively. The proportion of therapeutic recommendations based on high LOE went from 5% (3/59) in 2010 to 10% (10/102) in 2017 to 8% (12/153) in 2021.Regarding the evolution of evidence at the recommendation level, only three recommendations evolved from a lower LOE to a high LOE between the 2010 and 2017 guidelines, and none between the 2017 and 2021 guidelines . BetweenIn the two current US guidelines on PDAC treatment, the proportion of recommendations supported by high LOE is small, and the distribution of high LOE recommendations is not homogeneous across different disease stages and types of treatment. When comparing prior and current NCCN guidelines, the proportion of therapeutic recommendations with high LOE did not meaningfully improve over time.Our work is the first to study the LOE supporting US therapeutic guidelines in PDAC management. In 2016, a panel of expert pancreatologists found that, out of thirty-six clinical questions on pancreatic cancer management, only four had sufficient evidence in available guidelines for agreement . Other wWe also found great heterogeneity for evidence between PDAC categories. Indeed, most recommendations with high LOE were found for “potentially curable disease” and “chemotherapy”. These results underline the lack of evidence in PDAC for some types of interventions or some stages of the disease where RCTs are probably harder to conduct. Regarding classes of recommendation, only 7% (2/27) and 9% (12/127) of class I recommendations were based on high LOE. In other words, most of strongly recommended interventions are not currently supported by high LOE. When comparing prior and current versions of NCCN guidelines, there was no meaningful improvement of the proportion of high LOE recommendations between 2010 and 2021. One recent study focusing on the evolution of evidence underlying NCCN recommendations for a selection of solid cancers between 2010 and 2019 also reported an absence of change in proportions of Category 1 recommendations over time [Our work has several limits. First, there is heterogeneity between the two current guidelines regarding the total number of therapeutic recommendations. Indeed, in the NCCN guidelines, “resectable” and “borderline” diseases are separately described with dedicated recommendations. Additionally, the NCCN guidelines are constructed as a set of available options that are intended to help the physician choose the optimal treatment in a personalized manner for each patient. These reasons probably explain why there is a higher number of recommendations in the NCCN guidelines. Second, both guidelines use two different classifications of evidence based on different development methodologies. The definition of “high-level evidence” used by the NCCN for their Category 1 is not explicit in their guideline development manual. Therefore, even if our work was purely descriptive, we had to assume that what authors considered as high-level evidence was comparable for both guidelines. Third, the evidence supporting major society guideline recommendations is a surrogate for the totality of the evidence rather than a direct measurement with an inherent risk of subjectivity from each panel of experts involved in their development. Our results show a need for improvement in the evidence supporting PDAC therapeutic guidelines, not only for future treatments, but also for the ones that are currently used. Indeed, guidelines authors can only deal with the available evidence to develop recommendations, while highlighting the strengths and weaknesses of included studies. Previous works already pointed out the flaws in the current research system, including fragmentation with a lack of common goal or collaboration, heterogeneity of financial investment, and more reliance on industry funding, often resulting in narrowly focused trials with highly selected patients designed for drug approval, rather than to provide evidence for patients and decision makers ,23,24,25In conclusion, among current PDAC therapeutic recommendations in major US society guidelines, only a small percentage are supported by high LOE. Comparison with prior versions of comprehensive NCCN guidelines showed no meaningful increase of evidence over time. We need more collaborative effort to identify important clinical questions, but also to challenge the current framework of evidence in the context of an increasing number of diverse sources of data.


Tobacco control program leaders and their partners, who often present evidence to policymakers, can increase the use of evidence in program and policy development. However, up-to-date evidence from the scientific community about what works is slow to reach leaders. We describe efforts to understand and utilize tobacco control leaders’ preferences for receiving evidence and report on resulting dissemination strategies, translational products, and outcomes.N = 39). During meetings in February 2019 and October 2020, all CAB members were invited to participate in live polls consisting of six survey questions each. Questions addressed preferences for receiving scientific evidence and their anticipated use of ASPiRE translational products. Responses were analyzed descriptively and informed translational product development and communications with ASPiRE contact list members (N = 125). ASPiRE email and website interactions were tracked from March 2019 to May 2021 as a complementary indication of content use.This work is part of the Advancing Science and Practice in the Retail Environment (ASPiRE) Center, an interdisciplinary research center focused on understanding and evaluating tobacco retail policy. Participants were members of the ASPiRE Community Advisory Board (CAB), comprised of tobacco control leaders from 30 metropolitan areas representing all regions of the US plus nine representatives from leading national tobacco control organizations (n = 26) and 59% (n = 23), respectively. CAB members indicated preferences for email communication (33%) and webinars (31%), communications once per month (46%), and short-format documents (28%). In response, the team developed translational short-format products including case studies, fact sheets, and research briefs. On average, 52% (SD = 14%) of recipients opened the newsletter and 17% (SD = 9%) clicked a link within the newsletter. Overall, 95% of responding CAB members found the products useful and all responding CAB members reported using them to communicate evidence to policymakers, staff, and coalition members.Response rates for 2019 and 2020 CAB meetings were 66% (Our successful dissemination approach to making evidence more accessible and useable for tobacco control leaders could be adapted by researchers working with community partners to assess and respond to stakeholders’ preferences for receiving evidence in other areas of health policy. Tobacco use has declined significantly in the last two decades, by approximately 60 million people globally . Much ofYet even with these notable successes, tobacco use remains a leading cause of preventable death in the U.S. and globally , 4. As oIn the U.S., evidence-informed policies have traditionally proliferated from the ground up, with municipalities serving as test beds for innovative policies , 10. ThiHowever, the effective adoption and implementation of evidence-informed health policies is often a complex and painstaking process, even at the local level . DiffereThe needs and characteristics of the intended audience, for example, limited available capacity and time to digest and synthesize the body of scientific literature on a particular health issue among policy makers .The presentation of evidence in a format and dissemination channel that is accessible and desirable. Some policy audiences prefer short documents while others prefer full-length scientific articles. Some prefer electronic documents while others prefer paper documents. For instance, in a previous survey of 12 state health departments and affiliated partner organizations, participants preferred receiving research evidence through webinars and workshops and most frequently used research findings for assessment and evaluation, funding, and intervention selection .The content of the evidence and its relevance to the public health issue. For instance, presentation of a story-like narrative rather than lengthy statistical presentations, data visualizations over tables, and cost-effectiveness evidence. Information that is clear and actionable with recommendations .Organizational and community factors like community opinion about a particular public health issue .Active approaches, which push evidence towards end users, can facilitate the successful integration of evidence into health policy by tobacco control leaders , 17, 18.However, there are few practical and feasible examples of how to use community stakeholder preferences to guide dissemination efforts among tobacco control leaders and tobacco control policy audiences more generally.We report our efforts to translate and disseminate scientific evidence about tobacco control policy through the Advancing Science and Practice in the Retail Environment (ASPiRE) Center, a National Cancer Institute–funded interdisciplinary tobacco retail policy research center consisting of three major research projects and additional supportive cores. ASPiRE aims to build a strong scientific evidence base for effective retail policies to help reduce tobacco use, tobacco-related disparities, and the public health burden of tobacco use . As partCentral to this effort is partnership with a community advisory board (CAB) of tobacco control leaders, directors, and advocates. The ASPiRE Center researchers engage with the CAB formally on a bi-annual basis and informally so the CAB can provide guidance to ASPiRE research teams about retail policy activity and research needs, provide feedback on data collection instruments, identify sources of data concerning licensed tobacco retailers in participating cities and counties, and help disseminate research findings and policy tools to the field. As part of these meetings, the D&I Core team provides updates about new tobacco control science and materials available to CAB members and gathers information from CAB members about evidence needs.With the goal of enhancing the translational pipeline to increase use of scientific evidence in tobacco control policy and providing a model of how this might be accomplished, we describe our efforts to understand CAB members’ preferences for receiving evidence. We then provide examples of how we used reported preferences to develop translational materials and shape dissemination efforts. Finally, we describe CAB members’ reported engagement and use of disseminated materials.The work for the current study was carried out in three phases. First, we conducted a survey eliciting information from CAB members regarding their preferences for scientific evidence. We then developed a variety of translational products to disseminate scientific evidence in response to the outcomes of CAB members’ reported preferences. We conducted a follow up survey with CAB members to understand whether and how they used the disseminated products. We also tracked usage on two of our developed products the ASPiRE website and a bi-monthly newsletter. This project was determined to be non-human subjects research by the Institutional Review Board at Washington University in St. Louis.Recruited participants were members of the ASPiRE Community Advisory Board (CAB). The CAB is comprised of tobacco control leaders from 30 large metropolitan areas representing all regions of the United States and several representatives from leading national tobacco control organizations  and consists of approximately 45 members in total. Metropolitan areas represented on the CAB are illustrated in Fig. We used existing networks and past experience to identify an individual from each city who would be best suited to participate. If an individual was not easily identified, we relied on advice from the state health department or health advocacy organizations . All invited city representatives are engaged in tobacco control policy work. Most serve in local public health departments, with a few employed by the state health department or a non-governmental organization. Most have leadership roles in either chronic disease, community engagement, or tobacco control policy work within their organizations, though some are highly engaged staff-level personnel. In the instance of turnover, some members recommended their own replacements; in other cases, the CAB lead found a replacement who has deep knowledge and concern for tobacco control policy.Data were collected during our first and second CAB meetings in February 2019 and October 2020, respectively. All CAB members in attendance were invited to participate in a live poll using Poll Everywhere online software . At eachResults from the questionnaires were managed and analyzed using R statistical programming language version 4.0.3 . At eachFollowing a short description of CAB meetings and participants, we report findings from surveying CAB members on their dissemination preferences. We then describe the translational activities and products developed in response to those preferences. We also provide CAB member self-reported use of the evidence and results from an evaluation of CAB member satisfaction with the tailored dissemination efforts.n = 26) and 59% (n = 23), respectively. Most individuals served at the manager or director level in their organizations.Thirty-three of 39 CAB members attended the February 2019 in-person meeting. Twenty-three of 39 CAB members attended the October 2020 meeting held remotely via Zoom. Response rates for 2019 and 2020 CAB meetings were 66% (Respondents indicated a preference for receiving information primarily by email (33%), followed closely by webinars (31%) over other channels to hear about new retail policy resources. There was also interest in receiving information through websites, blogs, and conferences. Participants indicated very little to no interest in receiving information through social media or mail. Many (46%) preferred an update once per month.Participants desired a number of different formats for receiving scientific evidence. Fact sheets summarizing the current scientific evidence for an issue were the primary request  was launched in April 2020 as a communication and dissemination channel for sharing not only ASPiRE research findings, but also other retail policy resources, news, and updates from partner organizations. The website serves as an example of how our D&I Core has been responsive to CAB member feedback on several counts. First, ‘Internet’ was one of the top three channels identified in CAB member responses to the communication channel polling question. Second, the website houses a resource library that includes all types of materials requested by CAB members  and was designed for a broad audience of individuals working in tobacco retail policy and research, including those identified by CAB members . And third, the website is an ideal platform for responsive sharing of timely, relevant, and tailored ‘News & Updates’ identified by ASPiRE team members, CAB members, and partners across the life of the ASPiRE project. In response to CAB preferences for evidence dissemination modes, all materials to date have been shared with the CAB through multiple channels, including by email to CAB members, via virtual CAB meetings, and by posting on the ASPiRE website. The ASPiRE website  Tobacco Swamps Maps, and 3) Tobacco Sales Fact Sheets, which provide detailed information about tobacco retail density and proximity to key locales, areas of heavy retailer concentration, and tobacco sales [Tobacco Sales Fact Sheets, in keeping with active dissemination approaches of tailoring products for specific audiences, the D&I Core developed a one-page digest as a ‘cover’ to the 2 pages of detailed sales data. The CAB members who provided feedback shared their intention to use the detailed data sheets in their own internal planning and the one-page digest when speaking with policy makers. The D&I Core also worked with another ASPiRE research project to disseminate the Tobacco Swamps Dashboard, a city-specific, interactive dashboard which allows the user to project potential impacts of retailer policies for each locale (https://aspirecenter.org/tobacco-swamps/). All aforementioned products featured summary ‘fast facts’ about the data, data visualizations , plain language interpretations of the findings, and ASPiRE branding.While the website serves as both a channel for dissemination and a product, the D&I Core also developed a number of static products. As an example, the D&I Core collaborated with one of the ASPiRE’s research projects to develop three sets of city-specific products: 1)co sales . For theOn average, 61% (SD 7%) of CAB members opened the newsletter per month and 21% (SD 9%) clicked on a resource link within the newsletter. In our Fall 2020 CAB meeting, almost all (95%) CAB participants felt the newsletter was useful or very useful and was delivered at the right frequency, and 95% visited aspirecenter.org at least once in the first six months. Website analytics also suggest wider dissemination outside of CAB members. From April 2020 through July 2020 there were over 5,000 users and over 18,000 individual page views. Through the website, 46 additional (non-CAB) individuals signed up to receive communications from ASPiRE including ASPiRE eNews.In addition to the website, a follow-up poll of CAB members in October of 2020 showed that 70% had used these products to inform their work. CAB members reported using a variety of additional ASPiRE products Fig. , left. TAdditionally, our dissemination efforts were increased through the Campaign for Tobacco-Free Kids (a CAB member organization) in a joint multi-city media campaign to focus attention on the proximity of tobacco retailers to schools and the high retail density in low-income neighborhoods. The reach of and audience engagement with the two-week campaign was substantial: over 3 million broadcast viewers, radio listeners, and on-line readers in more than two dozen of the nation’s largest media markets viewed or heard the information. After the campaign, we observed a four-fold increase in traffic to the ASPiRE website.Similar to other areas of public health and social policy, the implementation of evidence-informed tobacco control policies remains the most effective and sustainable type of public health intervention to reduce tobacco use, tobacco-related disparities, and the public health burden of tobacco use. Policy evidence translation and dissemination are crucial for the development and promotion of evidence-informed policies yet remain understudied areas of research . This stSuccessful tobacco control interventions have long relied upon appropriate and broad dissemination strategies , 32. OurAs funders and governments encourage attention to leveraging scientific evidence for better policy impact , there aFor investigators who may be new to the field of dissemination for policymaking, there are several training opportunities to help become familiar with common dissemination frameworks, concepts, and approaches (like Designing for Dissemination) to help integrate their research into policy. Additionally, given the importance of community-based work to advancing health equity, it is important for researchers to know how to present and share information that will be used by—and shared by—community members –38. We aAs a tenet of implementation science, context should be taken into consideration when planning dissemination and implementation efforts, and a one-size-fits-all approach is likely to only be minimally effective , 41.  ThAs global momentum for retail-based tobacco control policy interventions continues to grow, considering stakeholder preferences for how evidence is translated to those who can take policy action is increasingly important. Policy researchers in academic environments can enhance the value and impact of their work by promoting awareness, uptake, and integration of research findings in the generation of evidence-informed health policies. The approach taken here for surveying intended audiences and responding to feedback by tailoring dissemination products and efforts could serve as an exemplar for health policy researchers engaged in intersectoral partnerships for improved evidence translation and use in policy development.


Forensic anthropologists perform specialised analysis, mainly involving skeletonised human remains, cadavers in advanced stages of decomposition, disassociated elements from the human body, and human remains in extreme carbonisation. The main objectives of the forensic anthropology expertise are human identification and assisting in determining the cause and manner of death. Estimating the time since death is also a priority for some cases, especially ones involving missing persons. This science works on individual cases, violent deaths, missing persons, mass disasters, suspected violations of human rights, and crimes against humanity. Forensic anthropological evidence is, in general, very sensitive. Thus, it is important to detail aspects relevant to the maintenance of the chain of custody at all phases of the investigation, as well as standardise the actions of the individuals involved. This aims to preserve the evidence integrity and sameness  is exactly and integrally the same one which was collected, corresponding, therefore, to “the same” , safeguarding its value. Brazil Law No. 13.964 of 14 December 2019 establishes and lists 10 phases related to the evidence chain of custody that must be followed. These newly introduced requirements resulted in the need for adaptation of the forensic, investigative, and legal actors involved in an investigation, and in the detailed description of the procedures for the different areas related to criminalistics, including forensic anthropology. The information provided in this article should be interpreted as recommendations, even though their non-compliance may weaken the investigative and forensic analysis processes in whole or in part. In the USA, the first concerns with the chain of custody emerged in the mid-1900s. However, there was no understanding regarding its use and obligation. Countless judges dismissed its need in favour of testimonial evidence or positive identification of real evidence historically related to the case [The establishment of the term Later, the theme gained more prominence with the book and episode: “The People Against OJ Simpson”, a case involving a famous former American football player, Orenthal James Simpson, accused as the main suspect in the murder of his ex-wife (Nicole Brown) and his friend  in 1994 . In the process by which inputs and outputs and associated information are transferred, monitored and controlled as they move through each step in the relevant supply chain” [chronological record of the handling and storage of an item from its point of collection to its final return or disposal” [Consequently, numerous and varied chain of custody concepts emerged. The International Organization for Standardization (ISO), through its standard 22095:2020, defined the chain of custody as “y chain” . In anotisposal” . Both ISThe involvement of Brazil in the discussions regarding chain of custody started in the first decade of the 19th century , 7. But corpus delicti” as soon as the fact is known is as old as the period of the Brazilian Empire. In the Code of Criminal Procedure of 1832, it is observed that the legislator was already concerned regarding the safeguarding of the element and its provable characteristics.In a way, the concern with “forming the Since then, other texts have also addressed the subject, and this is evidently reflected in the current doctrine. One of the forensic texts that summarises the question appears in reference , under tBy “defense of the material” we must understand its protection, so that nothing in it is lost, nothing in it is altered, allowing a perfect expert examination.This defense begins when the ‘scene’ is isolated. Isolation must be carried out by the policeman, in order to preserve the scene as he/she/they found it when he/she/they arrived”The relationship between what the author defined and what we understand today as an evidence chain of custody is clear. More than that, in line with Dias Filho , Porto  pointed The coherence between the forensic recommendations of Porto  and the The National Secretariat for Public Security (SENASP), bound to the Ministry of Justice and Public Security (MJSP), published Ordinance No. 82 on 16 July 2014, which established the guidelines for the procedures to be observed regarding the evidence chain of custody . The regcorpus delicti examination.An important contemporary Brazilian legal scholar on the subject, Prado , stated Notwithstanding Prado’s arguments, part of the legal doctrine understands, however, that the breach of the evidence’s chain of custody should be dimensioned in the valuation stage. The seriousness of the breach and the degree of effective contamination of its reliability should be assessed, so that there is the possibility of its admissibility to a greater or lesser extent .Anti-Crime Package [orpus delicti, the chain of custody and forensics in general”. In fact, practically the entire content of the SENASP ordinance was reproduced in the legal amendments implemented in 2019.Bill No. 6.341 of 2019 proposed an improvement in forensic and criminal procedural legislation , culmina Package . Among oWhen discussing the new Law No. 13.964/2019 that first addressed the phases and their descriptions on the evidence chain of custody in the Brazilian legal system, it may seem that the chain of custody theme is innovative in Brazil. However, as mentioned, the implementation of procedures related to the chain of custody in an avowed way in the law is just another advance in the modernisation of the Brazilian criminal procedural legislation regarding the preservation and reliability of evidence.chain of custody was legally defined as:The term …the set of all procedures used to maintain and document the chronological history of the trace collected in places or victims of crimes, to track its possession and handling from its recognition to the disposal.(Article 158-A of Law No. 13.964 of 2019)The term, in practice, aims to provide credibility and authenticity to the material provided as evidence, with specified characteristics to dispel doubts in its origin and movement. Therefore, currently, the chain of custody is the most critical process in the documentation of evidence and its importance can be evaluated by the quantity and quality of national and international publications and guidelines about its practice.Chain of Custody Technical Group Project: discussion, diagnosis, and recommendations after Law No. 13.964/2019” was developed, instituted through SENASP/MJSP Ordinance No. 282 on 21 May 2021, in the scope of the Working Group on the same topic, established through SENASP Ordinance No. 176 on 29 September 2020 [In this context, the “ber 2020 . The objComposed of nearly 150 professionals from multiple National Public Security institutions organised into 13 Technical Groups (TGs), the project’s team had the challenging mission of discussing procedures and mapping processes in the chain of custody in a national approach and multi-agency manner. It had to consider the operational, tactical, and strategic levels, with the goal of issuing recommendations and producing workflows that adapt the plurality and heterogeneity of National Public Security institutions to the minimally acceptable criteria of chain of custody.Given the above, this article aims to expose the discussions, diagnoses, and recommendations that encompass the work of the TG entitled Forensic Medicine, Toxicology, Forensic Anthropology, and Legal Odontology (TG MLTAFOL) and the General Coordination and Integration Group (CGI), based on extensive technical references on the subject. Such data and information presented here come from the integrated and multidisciplinary work of the members of the group. This work and the one in which this article is based, is the first to develop recommendations for establishing parameters for the chain of custody at a national level.Although the authors recognise that the discussions happened in a broader sense encompassing different forensic specialties, our goal here is to stress these recommendations in the practice of forensic anthropology in Brazil. The authors understand that some of the information exposed here can be extended to other forensic-related areas that deal with human remains, but we also know that there is variation across disciplines and their scope. Therefore, because of the depth of the discussions, we advise that any extrapolations outside the scope of forensic anthropology are made with their area-specific adjustments.Forensic anthropology analyses in Brazil are normally performed within the Medico-Legal Institutes (IMLs) in conjunction with the Institutes of Criminalistics (IC), inserted as part of the attributions of the official forensic experts. The forensic medicine experts and legal odontology experts are typically the ones responsible for the forensic anthropological examinations. The Federal Law No. 12.030/2009 addresses those who are the official forensic experts of criminal nature, namely: criminal experts, forensic medicine experts, and legal odontology experts . As a ruThe discussions regarding the chain of custody in forensic anthropology were first addressed in the TG MLTAFOL because these areas are all included in the IMLs in Brazil. The purpose of the established document was to ensure the effectiveness of the chain of custody of traces of Legal Medicine, Legal Odontology, Forensic Anthropology, and Forensic Toxicology interest in the phases of identification, security, documentation, collection, packaging, transportation, reception, processing, storing, and disposal of evidence. It also aimed to standardise the actions of the personnel involved to preserve the inviolability and suitability of the traces, safeguarding their evidential value.In this sense, the Trace Tracking Form   is at thThe examinations and data collection in a crime scene involving human remains are used to reconstruct and interpret the past events that led to the presence of a deceased individual. The information available on the scene, along with the human remains, are then referred for the examination at the IMLs in Brazil. The presence of professionals specialised in forensic anthropology at crime scenes is of great value for acting directly in the survey, mapping, and excavation processes (when needed) and the recovery of physical evidence . HoweverBecause the maintenance of the chain of custody goes beyond the mere traceability of a piece of evidence and applying proper methods and techniques by specialised personnel to guarantee the sameness and evidential value of the trace, proper personal protective equipment (PPE) must be always used. Proper PPE depends on the stage of decomposition of the identified, collected, and analysed remains, but should ideally minimally include gloves, cap, surgical mask, apron or protective overalls, and shoe protectors.General Evidence Custody Unit: for receiving, processing, and storing evidence associated with human remains ;Cold Chamber Custody Unit (Morgue): intended for receiving, processing, and storing cadavers;Ossuary Custody Unit: for receiving, processing, and storing skeletonised remains, bone elements, dental elements, and bone fragments.One objective of the IMLs is to establish the cause and manner of death and human identification. They should preferably allocate a physical space aiming at the custody and control of evidence that has forensic anthropological significance. These should comprise sections exclusively dedicated to the reception, processing, and storage of human body elements, human remains, dental elements, and bone fragments. The IML Custody UnitIn the internal structure of the IML focused on forensic anthropology, it is desirable that there is a specific Custody Centre for bones, herein called “Ossuary Custody Centre”. This should consist of a dry and airy room for the storage of urns, boxes, or bags with identified/numbered shelves to enable the efficient classification and searching of evidence, including isolated dental elements and bone fragments. Thus, when the forensic anthropological examination is completed, the bone elements or skeletonised human remains should be sent to the Ossuary Custody Centre for temporary or permanent custody. In the absence of expert and criminal interest, the recommended disposal rite for the release of the remains will be followed (described in more detail later in this article).The following discussions were based on the compilation of references mentioned previously in this article. Therefore, as we list the 10 phases that make up the chain of custody processes with their legal definitions, as referenced in Law No. 13.964 of 2019, the applications to forensic anthropology are exposed :The chain of custody begins with police or expert procedures in which the existence of a trace is detected. The first public security agent must be able to recognise that a crime was committed and identify the elements of potential interest.The ability to identify evidence of forensic anthropological interest is one of the crucial points for the investigation to follow the procedures in accordance with expert jurisprudence. It is therefore an essential condition for the other steps in the processing of a crime scene to be fully successful.in situ. In other words, a forensic anthropology expert can assure that any physical evidence not detected by unknowledgeable persons is identified and protected for posterior collection.It is recommended that an expert who works or has knowledge in forensic anthropology is present at the crime scene, so that the anthropological evidence is identified correctly, and the scene security is adequately modified to ensure the integrity and legitimacy of the traces Investigating a crime scene with proper identification of forensic anthropological evidence is crucial for the protection, recovery, and collection of such materials of interest. Evidence identification, as a first step, allows for the accurate collection and sorting of evidence that paves the way for an overall successful investigation. Ideally, forensic anthropologists should always take part in the crime scene investigation, using their experience to analyse the scene and recognise its associated materials as possible matters of investigative interest. The value of a forensic anthropologist at the scene can be exemplified when there is a need for excavation, identification of human or non-human remains, recognition of bone elements and fragments, interpretation of the scene and its context, and assurance that complete and thorough recovery of evidence is accomplished.The main risk during the evidence identification phase is the biological risks regarding the state of decomposition of the cadaver. In addition, there is the risk associated with the lack of knowledge when identifying materials, such as bone elements or fragments, and the inability to recognise a site as being of secondary deposition of human remains.The complex nature of sites, such as possible fires, landslides, mixed graves, and disasters, is the main vulnerability of the process. The search, location, and identification of traces can be hampered by the presence of other materials, by the fragile state of the traces of interest, and by the extent of the area to be surveyed.The public security agent who recognises an element as being of potential interest to experts is directly responsible for its preservation. The chain of custody processes then follows with the preservation of the crime scene.corpus delicti and any other analysis is carried out. For the purpose of examining the location where the offense was committed, the authority will immediately ensure that the situation does not change until the arrival of the official experts who will subsequently illustrate their reports with photographs, drawings, or clarifying schemes. The experts will record in the report the changes in the situation and will discuss the consequences of these changes in the dynamics of the facts.As soon as a public security institution becomes aware that a criminal offense has occurred, the police authority must go to the location and ensure that the scene is properly preserved until the arrival of the official criminal experts. They must also determine, if applicable, that an examination of the Entry of unauthorized persons into secured places is prohibited, as is the removal of any traces of crime scenes before release by the responsible official expert. The alteration of a crime scene is typified as procedural fraudComplementing the evidence identification phase, scene security has the important function of preventing access to materials of anthropological interest by people who may intend to subtract or alter them. Therefore, the scene must contain physical means to limit access, such as cones or striped tapes, and the perimeter must be monitored by public security professionals.One of the most important aspects of protecting the crime scene is to preserve it with minimal contamination and disturbance of the traces present. The first responder(s) must promptly remain alert to any people, vehicles, events, potential traces, and environmental conditions. The safety and physical well-being of officers and other individuals in and around the crime scene are the priorities of the initial responding officer(s).With the arrival of the crime scene official criminal expert and sometimes the official expert in the areas of forensic medicine or legal odontology, it is possible that the original scene protection method will be changed after a wide sweep. It may aim to cover a more extensive area or other areas that were recognised as related to the event.The main risk and vulnerability of non-existent or inadequate scene security is the removal of disassociated bone elements or other evidence associated with the event  or the contamination of existing traces.The human remains should always be photographed in the position in which they were found, as well as all external injuries and traces left at the scene of the crime. To represent the lesions found on the human remains, the official experts, when possible and considering their knowledge and limitations, should add photographic evidence, diagrams, or drawings to the examination report.As part of the procedures carried out when human remains are found, steps involving the survey of the environmental conditions of the location should be described. The vegetation, humidity, and type of soil in the region should be observed, with attention given to searching for traces that indicate the occurrence of any anthropogenic changes in the examined environment. There must be a detailed search for bones and their fragments, in addition to teeth that may have detached from the body after skeletonisation. The topography of the searched region should be considered. The surface layer of the soil can be sifted to search for bones and teeth and other traces that may possibly be associated with elements of interest found in the bones, such as projectiles expelled by firearms. Furthermore, it is essential that photographs are taken of the scene and any traces or evidence found. The positions of any traces should be associated with the location in accordance with the methodology that the official expert deems most pertinent.After completing the peri-necroscopicin situ, collected, and packaged individually in an envelope that must be sealed following the general procedures, keeping the related specificities according to the nature of the evidence. Associated traces that the official expert believes do not run the risk of detachment from the cadaver or human remains should also be marked as an observation in the TTF.Any trace associated with the human remains that may come off from its body surface or body cavities must be photographed Incorrect or inadequate documentation may generate inconsistent information or lack of information necessary for the report and its context, especially if it is going to be collected and processed, after which such information cannot be supplied. This inadequacy could possibly be brought up in court to render the evidence inadmissible of evidence or lessen its value and impact.There is great vulnerability when teams process the scene without the basic knowledge necessary to identify traces as of forensic anthropological interest, compromising their documentation and posterior collection.The collection of traces should preferably be carried out by an official expert, who will provide the necessary referral to the Custody Centre even when additional complementary analyses are required. All traces collected during the investigation must be treated as described in the legal and criminal procedures, with the central body of official criminal expertise being responsible for detailing the manner of compliance.The cadaver/human remains may still have clothing or other materials, such as wrappings, associated materials, or covers, that can be partially or completely removed from the scene at the discretion of the official expert. They will assess the indispensability of such action for the examination of the body and the limitations related to the context, such as improper exposure of the body. Items will be removed after being packed and deposited in a mortuary bag or paper bag, then will be duly registered in the TTF. If the official expert believes traces could possibly be lost, they will be packed in a proper envelope or bag to be sealed. The proper TTF will then be completed, where the reason for its removal from the scene will be recorded and the type of trace collected will be specified, such as a blood stain or semen sample.The step described above is subject to careful documentation. Two concerns of forensic anthropological analysis are the registration of evidence origin and its context. Provenance refers to the exact location of an item in three-dimensional space, reflecting the latitude, longitude, and vertical positioning. Context is the exact time and space of an object considering its association and relationship to other items. Undoubtedly, this information is lost the moment objects are collected, as the investigation and collection process impact a scene from the moment they begin. Official experts have only one chance to extract traces completely and correctly, occasionally referred to as “controlled deconstruction”.in situ, emphasising that all these data must be consulted later during the writing of the report. Although there is no strict order for the process of collecting traces, some types of materials must take precedence. For example, traces that are transient, fragile, or can be easily lost have priority. When dealing with disassociated human remains or fragments of bodies, each element must be treated as unique. In situations of graves with multiple bodies, experts without proper forensic anthropological knowledge must avoid reassociating disassociated bone elements. Emphasis must be given to the documentation phase, so that information can be retrieved later for more specialised analysis.The effective collection of the trace is dependent on its documentation The risks and vulnerabilities during the collection of traces of forensic anthropological interest at the scene arise from the very nature of this evidence. They are often fragile and associated with other potential traces. Compromising the integrity of the traces during collection can also result in contamination of other traces and expose the expert team to biological risks.The receptacleThe cadaver (or human remains in different stages of decomposition) will be placed in an impermeable mortuary bag with adequate resistance to loading the body. The bag should preferably have at least four handles for safe collective loading of its contents, ensuring its integrity and greater ergonomics for those responsible for carrying it, have two zippers or a zipper and associated device at the end that makes it possible to seal the bag to guarantee its inviolability and suitability. This zipper, together with the seal, will have a copy of the label/tag that was attached to the body.It is recommended that skeletonised remains, disassociated elements, bones, fragile materials, and clothing be packed in paper bags to prevent any moisture that can result in fungi or mold formation, which would hinder the further processing and analysis of these elements. Each element/trace collected must be immediately placed in an appropriate primary container and then into a secondary container, which must be completely sealed with tape.The official expert responsible for the scene processing must at least supervise the disposition of the cadaver/human remains in the mortuary bag, personally close the bag, fasten the seal to the zippers or zipper/closure device, and place the corresponding label. Once the mortuary bag is sealed, the official expert must take at least two photographs of the installed seal and the label attached to it, which must clearly show the printing on the label, the specific numbering of the seal, and the immediate surrounding context. After placing the mortuary bag in the tray of the transport vehicle and verifying the documents, the person responsible for transport must fill out and sign the item related to the transport information contained in the TTF. The official expert must then proceed to photograph the completed FAV.All receptacles must be sealed with individual numbering to guarantee the inviolability and suitability of the trace during transport.The removal of human remains from the crime scene will only take place after the completion of the criminal investigation activities and the subsequent authorisation of the person responsible for the judicial police work. The crime scene expert must supervise the collection of all materials and ensure that the human remains have been deposited in the transport compartment tray to preserve its integrity. The vehicles of the IML fleet, funeral homes, or other companies contracted for this purpose must have an adapted cargo transport compartment with appropriate individualised trays and adequate refrigeration to ensure the integrity of the human remains.Professionals responsible for transport should check the information on the FAV and its consistency with the material to be transported. They must also observe the specific conditions for transport, which will be described in the TTF, as well as instructions for filling out specific data in the TTF related to transport. Any non-conformity must be reported to the official expert at the scene and, if the non-conformity(ies) persists, they must be recorded, specified, and reported to the official expert at the scene in the respective TTF.The IML, whenever possible, should promptly respond to requests for the collection of cadavers/human remains. When it is not possible to quickly respond, the responsible unit must immediately inform the police authority of this circumstance, stating the reasons for impediment.The vehicle used for transport, after collecting the cadaver, human remains, and/or associated evidence of a crime scene, must go immediately and directly to the destination IML without unnecessary stops or detours. When this does not occur due to force majeure (e.g. weather or traffic), the reason(s) or complications must be reported in the TTF. Likewise, any intercurrences that may change the conditions of transport or prevent the guidelines given by the responsible official expert from being followed will be reported and justified by the carrier at the FAV.When transporting bone elements, fragile, fractured, or charred bones, the possibility of using additional cushioning systems during packaging and transport should be considered to preserve the integrity of this evidence. The guidelines will be included in the FAV of the evidence and will be passed on to the person responsible for the transport.The person responsible for receiving the evidence must check the TTF, paying special attention to any recommendation regarding transport/storage, such as special care given to fragile bones or loose teeth. After verification, the person responsible should register the receipt with the TTF, note the time at which it occurred and point out any inconsistencies between the information and the mortuary bag and/or containers with other traces. Such non-conformities must be registered in the TTF by the professional and immediately communicated to the police authority.Ideally, the cadaver, human remains, and/or associated evidence should be received properly packaged in sealed bags and accompanied by the respective TTFs. The absence of the recommended recipients or bags, while weakening the chain of custody, is not a sufficient reason for its total breakage or for the inadmissibility in processing the evidence being received. Unless such packaging poses a risk to the integrity of the traces or especially to personnel or infrastructure, it is recommended that traces be accepted and received in containers other than the standardised ones, especially if minimally adequate and with justification. Care should be taken to register any such non-conformity in the necessary documents.For the entry of human remains into the IML through its Custody Centre, it must be formally registered in an “electronic medical record”  with the IML internal tracking number, which can be used as a tracking code. If a new number is given, it is essential that the document refers to the original case number and the number of the TTF that accompanied the traces from the original scene to the IML.Location TTF number—unique numbering;Case number and related judicial police unit;Place of origin;Person responsible for transporting the human remains;Tracking code/protocol number—internal to IML;Nature of the exam requested;Identification and signature of the person responsible for receiving the body.The registration of the cadaver in a computerised system  must include the following information:Upon receiving the request order for the examination, the IML Custody Unit must verify the agreement with the information contained on the plastic seal and label of the mortuary bag, in the “electronic medical record” (or proper book), and in the TTF of the human remains.In situations where the IML does not have an infrastructure or human resources capable of performing the specialised examination, it must receive the cadaver/human remains and arrange transport to another IML, recording this in the TTF and informing the requesting authority.Upon receipt by the Custody Centre (morgue), the mortuary bag can only have its seal broken and the human remains exposed by the official expert(s) of the forensic medicine or Legal Odontology area designated for the examination.The sealed recipient can only be opened by the official expert who is going to conduct the requested analysis and, with good reason, by an authorised person. After each time the seal is broken, the name and registration of the person responsible, date, place, purpose, and information regarding the new seal used must be included in the TTF. The broken seal must be packed inside the new container.The peri-necroscopic examination  will be carried out by the official expert at the scene and is part of the processes related to the crime scene itself. The limitations related to the context, their professional ethics, previous experience, and professional background should be considered.When evidence processing takes place at the IML, other chain of custody phases also occur concomitantly, such as the identification and documentation phases. The official expert makes the selection and determines if any evidence received is of interest to Forensic Anthropology. In addition to the types of evidence previously described as having forensic anthropological interest, cases of cadavers/human remains where it is not possible to perform a conventional autopsy must be referred for anthropological examination. This can occur at either the same institute or a separate location that has a specialised Forensic Anthropology service.The official expert responsible for the forensic anthropological analyses should start the necroscopic examination by verifying the bag/seal and note any nonconformities in the respective FAV. The official forensic expert in the medical/odontology area will also be responsible for collecting, storing, and forwarding the associated evidence . Care must be taken to allow for the discovery of additional traces, such as entomological or ballistic evidence, during processing. Any additional traces must be treated in accordance with the procedures applicable for their nature and any necessary referrals to other laboratories must be made by filling out the appropriate documentation.postmortem data. Preferably, this standard documentation should be received directly by the Forensic Anthropology service at the IML, where interviews with family members are also carried out. This documentation must, whenever possible, be digitised and stored in the institution’s system and/or in the Custody Unit . It must also contain the human remains data, TTF number, and internal IML tracking code.If identification of the cadaver/human remains is possible, information regarding missing persons should be requested to compare with If the human remains require reconstruction for better examination during analysis, the process and materials used must be properly documented. Any methods of reconstruction or materials used must be reversible with non-destructive ways to aid documentation. That means that the methods for assembling fragmented bones should be reversible by using an adequate solvent, as in the case of inadequate gluing, or of a necessary modification when an additional bone fragment is found.Adequate laboratory lighting is crucial for traces to be analysed effectively and efficiently. Lighting also assists in the documentation of evidence, providing that the images produced are trustworthy to the analysed physical trace.The parallel documentation phase that occurs with the evidence processing within the IML  consists of photographic records of the trauma, pathology, and elements used for the biological profile evaluation, individualising characteristics, or any alterations present in the human remains. Photography is the simplest and most effective way to perform this step. More than any hand-written representation, photography can provide important details for elucidating the individual’s identity and cause and manner of death. It is difficult to determine the ideal number of photos that should be taken. However, all records should be made together with the internal record number of the remains. In general, photos should preferably be orthogonal, in small, medium, and large scale, where the character or feature of interest is clearly depicted.Another effective form of documentation is an imaging exam. Radiographs make it possible to identify bone fractures and locate firearm projectiles or other objects foreign to the human body. Computed tomography (CT) and magnetic resonance imaging (MRI), which are still not widely used in forensic sciences, make it possible to perform re-examinations through image reconstruction without the need for exhumation of the body in some situations. All images or videos generated must include the human remains data, TTF number, and internal IML tracking code. This documentation should, whenever possible, be digitised and stored in the institution’s system and/or in the Custody Unit.The description and documentation of the analysed material is of paramount importance because some processing methods are destructive, such as the removal of soft tissue. All procedures, equipment, techniques, and methodologies relevant to the processing of anthropological evidence and present in the anthropological report must be described and include any appropriate scientific references.For bodies at different stages of decomposition and not completely skeletonised, it is recommended that caution be used during the maceration process. Because of differences in the laboratory infrastructure, it is understood that total body maceration and cleaning often become infeasible. Therefore, it is recommended that only the essential elements for specific analyses and estimates of the biological profile are macerated and cleaned. These elements can include the pelvis (pubis), skull, long bone , and any element that is of interest for analysis of trauma or pathology.After the procedures have been finished or any technical issues have been identified, the official expert who performed the analysis/breaking of the seal must supervise the repackaging of the human remains in a mortuary bag  and reseal it. The cadaver/human remains will only return to the Custody Centre in a duly sealed mortuary bag  with a new number registered in the FAV by the official criminal expert.All Criminalistics Institutes must have a Custody Centre for the custody and control of traces, and its management must be directly linked to the central body of official criminal expertise.Every Custody Centre must have protocol services with a place for conference, reception, and return of materials and documents, enable the selection, classification, and distribution of materials, and be a safe space with environmental conditions that do not interfere with the characteristics of the evidence. At the Custody Centre, the entry and exit of traces must be filed and all information pertinent to the investigation, including the case number, must be recorded. All persons who have access to the stored trace must be identified and the date and time of access must be noted. When processing the stored trace, all actions must be registered, including the identification of the person responsible for processing, as well as the destination, date, and time of the action.After the specialised analysis has been conducted, the material must be returned to the Custody Centre and must remain there. If the Custody Centre does not have space or conditions to store certain materials, the police or judicial authority shall determine the conditions for storing said material in a different location upon request of the director of the central institution of official criminal expertise.In laboratory settings, experts will keep enough material for the possibility of a new analysis request. If there is potential evidential value, the skeleton, bone elements, or associated evidence must be safely kept at the Ossuary. A plastic burial box, archival skeletal remains box, or similar container should preferably be used for storage, provided they have perforations in each end of the lid that allow them to be properly sealed. It is recommended that two seals with unique numbers are provided to preserve the inviolability of the box. The box containing the evidence must be accompanied by the respective TTF.In cases of violent death, clothes and other belongings with evidential value that have been removed from the human remains at the time of the necropsy will be packaged, registered in their own TTFs, and stored at the Custody Centre of general traces until they are processed. After processing/analysis, the responsible official expert will return the post-processed/remaining material to the Custody Centre, which will be communicated to the responsible Police Authority. Clothes and belongings removed from the cadaver at the time of necropsy that have no recognised forensic interest will be packaged, identified, and sent to the Custody Centre for general traces. They will remain at that location and be available for withdrawal by the family/representative(s) for a period of 15 days, after which they will be properly discarded.antemortem data, the skeleton/bone elements may be kept in custody at the Ossuary for any time that is justified by its current or potential evidential value. If the Custody Centre of the IML does not have space or conditions to store the bones or other traces, the police or judicial authority must be informed to determine the conditions for storing them in a different location, upon request of the IML Director.After the forensic analysis of the traces, their respective TTFs will be stored at the Custody Centre in an area where employees can exclusively access them. An efficient cataloguing and searching system will be maintained. If there is interest from the expert institute and/or the Public Administration, for example, if they are awaiting complementary examinations or In this proposed model, the traces must be transported to the Custody Centre for final storage until their disposal. There is an exception in some special situations, such as specific evidence like cadavers and bones, where the disposal management will be coordinated by the Custody Centre and carried out directly by the Ossuary.The person responsible for releasing the cadaver/human remains must check the documentation that accompanies the body/bone elements and consult in the reporting system and with the previous responsible official expert, if there are any pending issues. The release of the cadaver/human remains must be included in the respective item/sub-item in the TTF. The document must also contain the status of the cadaver/human remains Disposal of human remains refers to the procedures for releasing, donating, cremating, or burying them. The procedures should follow the laws and regulations of the country, as well as state decrees that vary throughout Brazil. Identified cadavers/remains can be delivered to either the first-degree family members or their legal representatives or to other relatives who legally request the cadavers/remains, pending judicial authorisation. Unclaimed cadavers/remains can be buried or donated to other institutions (academia or research) after the specific number of wait days legally established by the State. Human remains can only be cremated if they have been positively identified and the deceased individual has specified their cremation intention in legal documents in cases of natural death or with a judicial police authorisation in cases of violent death. In cases of unidentified bodies, the importance of controlling the burial site and subsequent storage in the cemetery’s ossuary is highlighted, following the same recommendations as the Ossuary in the IML. This allows for easy location of them if a future identification becomes necessary. Furthermore, the State allows for the donation of unidentified cadavers/remains. However, the authors do not recommend the donation of unidentified human remains for ethical and social reasons.peri-mortem trauma, or that may assist in establishing an identity in a case where future positive identification is likely or that a previous identification can be contested, may be retained after the rest of the remains are discarded. This can only be done, however, with the express permission of the Chief Medical Examiner and with the knowledge of the investigators. The chain of custody must then reflect which bones were returned and which were retained.Skeletal material is often kept by the forensic anthropologist in secure storage facilities until the responsible investigative authority has made the final determination for their disposal. Bones that show evidence of specific Evidence of forensic anthropological interest can involve human remains or bodies in conditions of a complex nature, including bodies that can be burned, fragmented and in advanced stages of decomposition. This evidence can be located both on the surface or buried in graves and is generally very sensitive. Forensic anthropological evidence can be associated with crime scenes involving violent deaths, accidents, fires, disasters, and situations of a political or humanitarian context as in human rights violations.Therefore, it is important to detail aspects relevant to the implementation and maintenance of the chain of custody of forensic anthropological evidence. The actions of the professionals involved in the movement or manipulation of the evidence in question must also be standardised. It is noteworthy that the multidisciplinary work involving the interactions between different agencies and actors of Public Security and other institutions and their specific responsibilities need to be coordinated and well defined to avoid interference. This can prevent the investigation from being compromised.This article presents the first recommendations for the evidence chain of custody in forensic anthropology in Brazil, which will help the development of the field. The importance of following the recommendations proposed here is highlighted, based on minimum standardised practices, to avoid compromising the evidence. Furthermore, this document can generally guide institutes and agencies with varied technical capacities and resources with publications of protocols, decrees, ordinances, circulars, and other internal legal norms that are well defined and publicised. This complements and helps apply these and other recommended practices and procedures.It is suggested that all phases of the chain of custody process described here are strictly followed, and that it is understood that phases can sometimes occur simultaneously, such as evidence identification, documentation, and processing. If it is impossible to comply with any of the recommendations, the noncompliance must be registered and documented as part of the chain of custody.Daubert.The authors understand that the chain of custody goes beyond the insurance of documental registration and traceability. The weakening of the chain of custody, even when there is no break in the traceability of the evidence, impacts the analysis of the sameness and appropriateness of the evidence. This precariousness and instability, in turn, impact the conditions of the evidence during its processing and, concomitantly, may alter its natural state. Hence, to maintain the robustness and admissibility of the evidence, we must ensure that adequate methodologies and techniques are being applied by proper specialised professionals following the considerations also established by Furthermore, it is recommended that the actions of the personnel involved are ideally standardised to preserve the inviolability and suitability of traces related to forensic anthropology, safeguarding their evidential value. Therefore, adapting the procedures correctly is essential to strengthen the expert evidence, which must be reputable and lawful, and to mitigate possible legal questions regarding the evidence and methodological and technical procedures applied throughout the investigation.


Uncertainty is ubiquitous in science, but scientific knowledge is often represented to the public and in educational contexts as certain and immutable. This contrast can foster distrust when scientific knowledge develops in a way that people perceive as a reversals, as we have observed during the ongoing COVID-19 pandemic. Drawing on research in statistics, child development, and several studies in science education, we argue that a Bayesian approach can support science learners to make sense of uncertainty. We provide a brief primer on Bayes’ theorem and then describe three ways to make Bayesian reasoning practical in K-12 science education contexts. There are a) using principles informed by Bayes’ theorem that relate to the nature of knowing and knowledge, b) interacting with a web-based application (or widget—Confidence Updater) that makes the calculations needed to apply Bayes’ theorem more practical, and c) adopting strategies for supporting even young learners to engage in Bayesian reasoning. We conclude with directions for future research and sum up how viewing science and scientific knowledge from a Bayesian perspective can build trust in science.The online version contains supplementary material available at 10.1007/s11191-022-00341-3. Uncertainty is ubiquitous in science. Consider, for instance, uncertainty because instruments cannot measure the thing they purport to measure with perfect precision or the uncertainty due to differences in observations made at different points in time Fuller, . AnotherPast research indicates that scientists, historians, and philosophers are aware of the uncertainty and limitations associated with reasoning from scientific evidence under conditions of uncertainty  psychologists using Bayesian models of cognition Gopnik, , (b) staprobabilistically, as probabilities can provide a language for expressing the degree of uncertainty in our knowledge in a wide range of domains  but areAnother example of how probability and uncertainty are central to scientific concepts and respective learning activities is evolution  have been criticized for fostering black or white thinking: either accept or reject the null hypothesis, leaving little room for uncertainty even when there is  that are used to make inferences from scientific data  Bayesian manner, Gigerenzer and colleagues provided essential insights into the underlying mechanisms for the occurrence of these biases. Their research suggests that the biases are at least partly the result of information about probability and uncertainty being provided in a way incompatible with the heuristics that people develop from their everyday experiences , recent work using Bayesian models considers the differences in the reasoning ability of children and adults to be a matter of degree, rather than one of a kind. From contemporary views of development, children hold initial ideas and understandings that they change (or update) in ways concordant with how Bayes’ theorem represents the updating of an initial belief in light of data , or our posterior, is the confidence we can have in the hypothesis H after updating our initial confidence, or our prior, p(H) based on consideration of the new evidence, expressed in the updating factor R where:R is equivalent to the predictive updating factor in our earlier example. Thus, R > 1 represents confirmatory evidence, while R = 1 represents inconclusive evidence, and R < 1 represents disconfirmatory evidence. Guidelines for choosing an adequate R exist , the initial confidence in the hypothesis, ranges from 0 to 1, with p(H) = 0.5 representing maximum uncertainty, i.e., having no ideas about the validity of the hypothesis.Note that mathematical. Still, Bayes’ theorem also includes an epistemological component—a component related to what is known about the world. What counts as prior information should be construed very broadly—it encompasses subjective judgments of how likely an event is and knowledge of empirical data from other related events.Bayes’ theorem is a mathematical procedure to understand new evidence in light of prior information. In this way, updating what is already known is normative to the extent that it is the derivation of the laws of conditional probability.The usefulness of Bayes’ theorem lies in how it presents a flexible yet principled way to update what is known in light of the evidence. Bayes’ theorem is not a cure-all; it is, instead, a formalization of something scientists and people alike already do: interpret evidence in light of what is already known. Moreover, it is epistemologically As an example of the application of Bayes’ theorem, consider the following. The Hemlock Wooly Adelgid is an invasive insect that feeds on Eastern Hemlock trees, a tall-growing pine tree found in the Eastern USA. Because infestations can kill Eastern Hemlocks rapidly, in many affected areas, people take steps to protect Eastern Hemlocks that are affected by the Hemlock Wooly Adelgid; some systemic treatments can be effective  may be interested in the proportion of Eastern Hemlock trees within a specific area that exhibit signs of infection: diseased trees with visible white “cotton ball” clumps at the base of the needles of affected trees. Let us consider that in the location we are examining, each Eastern Hemlock tree grows about the same distance apart from every other tree . Before beginning an analysis, we need to establish what prior information we have: the relative plausibility of the different values for the proportion of affected Eastern Hemlock trees. Given what they learned in class and what they noticed walking into their school, the student’s best guess may be that about half of the Eastern Hemlock trees on their school playground are infected. They would not be surprised if the proportion of affected trees was between 30 and 70%, but—based on what they learned and observed—they would be somewhat surprised to find either no affected trees or that all the trees were affected. We can capture this background knowledge in the dome-shaped distribution shown as the dashed line in Fig. Y representing infected and N representing not infected) are {Y, Y, N, Y, N, Y, Y, N, Y, N}: six infected trees and four not infected trees. The question is how we can use this data to inform our knowledge about the proportion of trees that are probably infected. Here, Bayes’ theorem comes in. It states that at any point in time, our knowledge about the world after observing new evidence, the posterior, can be obtained by multiplying our prior information, the prior, with something called a predictive updating factor . p(θ), the prior, represents our prior uncertainty about that knowledge  is the likelihood, that is, the extent to which the observed data were expected under θ, i.e., our prior knowledge of the world. Second, p(data) is the extent to which the observed data were expected across all possible values of θ. If p(data | θ) > p(data), the predictive updating factor will be larger than 1, meaning that our knowledge about the world θ predicts the data better compared to the average across all possible values of θ. Consequently, when we multiply the predictive updating factor with our prior, the value of our posterior p(θ|data) increases, representing reduced uncertainty of our knowledge about θ. Conversely, if p(data | θ) < p(data) our understanding of the world does not help to explain the data, the predictive updating factor will be smaller than 1, and the uncertainty of our knowledge about θ will increase.θ, i.e., that the proportion of infected trees is somewhere between 30 and 70% and probably neither very low (below 10%) nor very high (above 90%), then when we average across all possible values of θ, i.e., those that include very low and very high probabilities, p(data | θ) > p(data) and the predictive updating factor is larger than 1. The value of our posterior p(θ|data) increases. Specifically, this results in the posterior distribution shown as the solid line in Fig. θ. In addition, the posterior distribution is higher than the prior distribution for values of θ between approximately 0.4 and 0.75 values of θ predicted the data relatively well and have therefore gained credibility. In contrast, values of θ lower than 0.4 and higher than 0.75 predicted the data relatively poorly, which is why they have lost credibility compared to the prior.What happens when we take our data and plug it into this equation? As the string of observations—six infected trees and four not infected trees—is more likely given our prior knowledge of ow below 0% nor veY, and in light of the prior, this makes the proportion of infected trees a bit higher. This slight change in knowledge is reflected in the difference between the distributions on the top two lines in Fig. Y has nudged the distribution a little to the right.Although we have demonstrated this updating process in a single step, it could also be executed sequentially, one tree at a time. For instance, the first observation we make is a Y, and line “2” shows that the resulting posterior distribution is nudged to the right once more. At every stage in the sequential updating process, the posterior distribution based on the observations seen so far becomes the prior distribution for incorporating the information from the following observation. Specifically, the changing distributions in Fig. Crucially, the “nudged” posterior distribution after the first observation now takes the role of the prior distribution ready to be updated by our second observation. The second observation is again a qualitatively—our assumption for most K-12 science classrooms—the features of Bayesian reasoning can help bring a sense of coherence to the many ways in which uncertainty is manifest when students engage in scientific practices  prevent scientific progress. This principle expresses the Bayesian degree of belief epistemology, exemplifying that scientific knowledge is tentative and that scientists should not make absolute or certain claims. Lindley popularized this idea in statistics and coined it “Cromwell’s rule” . The descriptions of the science practices in the Framework . The widget is shown in Fig. https://kubsch.shinyapps.io/Confidence_Updater/. This widget allows students to choose values for the strength of the new evidence—R—based on their interpretation of the evidence and p(H) based on their initial confidence. After performing the needed calculations, the widget returns a textual statement about updated confidence, p(H|E), in the hypothesis after considering the evidence and an optional numeric value for the confidence level.To support students’ focus on the conceptual elements of updating their confidence in a hypothesis, we build on Warren’s , 2020 wop(H), as well as the predictive updating power of the new evidence, R. One can see the example output in Fig. Using the widget, one can obtain an estimate—based on Bayes’ theorem—for the confidence one can have in a hypothesis based upon the degree of one’s belief in the initial hypothesis—one’s prior—be open to new evidence, is emphasized as a natural consequence of Bayes’ theorem and the options absolutely certain that it is correct and absolutely certain that it is incorrect in the “How sure are you about your hypothesis?” section of the app. When students select from among these options, p(H) is set to 1 (certain that it is correct) or 0 (certain that it is incorrect), respectively. In such cases, neither the tentative (or changeable) nature of scientific knowledge nor the empirical basis of science is manifest. However, both are key elements of science  and considering the new evidence becomes pointless. In other words, no amount of data may change one’s belief in such cases. From this perspective, a question could be not scientific, as empirical evidence has no bearing on the answer to the question. If students selected any of the options that are equivalent to p(H) = 1 and then they observe strong contrary evidence and wonder how this does not affect the updated confidence are observing the evidence, a teacher could refer to the first principle—be open to new evidence—and point out to students how this degree of belief can inhibit any changes in beliefs even when confronted with strong evidence.Consequently, whatever updating factor As Warren  points oaccount for what is already known, appears in the wording of the prompt for selecting p(H) and becomes visible to students as it effectively moderates the power of the evidence. When prior beliefs and evidence align, the updated confidence is larger in comparison to either having no idea before or having prior beliefs that do not align. Students could notice this if they compare the updated confidence p(H|E) for students that had the same prior belief but evaluated the evidence differently or had different prior beliefs but evaluated the evidence in the same way. Again, as Warren , inverse, or quadratic relationship for this relationship—when resistance is held constant. Based upon their initial ideas—that the relationship is proportional, inverse, or quadratic, they may test their hypotheses using the widget. Specifically, following the second principle, students can now specify their prior confidence in their group’s hypothesis. Again, students may choose different priors based on their individual experiences. They may record several current measurements for different voltages and then graph the data. Figure How does using the confidence updater change a typical science class activity? Here, we sketch how using the confidence updater can provide rich opportunities to discuss and reflect on epistemic attitudes. A standard activity at the middle grades’ levels is to understand the relations between amperage, R, they are primed to consider to what extent the evidence is consistent with their hypothesis relative to an alternative hypothesis, reflecting the third principle. Looking at the graph, one could see evidence for a proportional relationship as well as a higher-order positive relationship )—in their hypothesis and the evaluation of the data, which will be different across groups. If students compare their results within groups, they should see how their initial confidence influences the effect of the evidence. However, if they repeat the activity, they should see how consensus is approached over a few iterations unless anyone chooses p(H) = 0 or p(H) = 1, which points, again, to the importance of the first principle  articulated whether the game was fair and (b) their confidence in their beliefs about the game’s fairness. Three of the four games were designed to make determining their fairness challenging. For playing the games—and using a statistical software tool for learners, TinkerPlots  by prompting students to consider both their beliefs and confidence throughout an activity, which can help students to begin to understand the three principles that characterize Bayesian reasoning.We have covered a lot of ground to this point, starting with prior research on uncertainty and Bayesian perspectives on science teaching and learning through a primer on Bayes’ theorem and three practical ways to introduce Bayesian reasoning to K-12 students. As we argued in the Introduction, the position for which we are advocating builds on and is intended to extend past research that makes a case for a Bayesian approach to argumentation . In this way, we argue for the use of a Bayesian perspective that could influence research about (and teaching to support) learners’ epistemic considerations and how learners’ ideas change over time—factors that may have a bearing on how they understand science outside of school, or later as adults . However, when people—across educational backgrounds—refuse to take the COVID vaccines because they judge them as unsafe , it becomes painstakingly clear that science education often does not enable learners to analyze and interpret data in practical and meaningful ways. In line with researchers emphasizing the epistemic aspects of science teaching and learning  informed by a Bayesian perspective could be helpful to create. As we have noted, analyzing and interpreting data is a core scientific practice. In line with this goal, the National Research Council’s  Framewor. Specifically, a Bayesian perspective can support learners to understand key concepts about the nature of science—such as the tentative (or uncertain) nature of scientific knowledge  but also as a type of cross-cutting concept Below is the link to the electronic supplementary material.