Implementation of the REFLECT Communication Curriculum for Clinical Oncology Graduate Medical Education.

Background: Communication and interpersonal skills are essential medical components of oncology patient care. Patients and families rely on physicians for treatment, expertise, guidance, hope, meaning, and compassion throughout a life-threatening illness. A provider's inability to empathize with patients is linked to physician-related fatigue and burnout. Because oncology training programs focus on teaching evidence-based medicine and clinical acumen, little time may be dedicated to professional development and acquisition of interactive skills. Traditional communication courses typically include two components: formal, knowledge-based learning skills, which are gained from didactic lectures, and role-playing, which usually occurs in small groups. We report the implementation of a novel longitudinal communication curriculum for trainees in Oncology. Materials and Methods: At a single-center institution, an innovative communication curriculum titled "REFLECT" (Respect, Empathy, Facilitate Effective Communication, Listen, Elicit Information, Compassion, and Teach Others) was implemented for radiation oncology residents and medical oncology fellows to improve and refine physician/patient interactions. All oncology specialty residents and fellows were eligible to participate in this communication curriculum. The curriculum emphasized a reflective process to guide trainees through challenging scenarios. Results: Since October 2018, this comprehensive course consisted of quarterly (four hour) workshops comprising assigned reading, knowledge assessments, didactic lectures, expert guest lecturers, standardized patient simulations, role-playing, patient/expert panels, coaching, reflective writing, and debriefing/feedback sessions. The curriculum provided longitudinal communication training integrated with the learners' daily physician/patient encounters rather than occasional isolated experiences. Fifteen workshops have been completed. Each focused on navigating challenging situations with patients, loved ones, or colleagues. Conclusions: Future directions of the curriculum will entail improving the communication skills of oncology trainees and gathering communication improvement data to assess the program's success formally.

Deep parasternal intercostal plane nerve block: an anatomical study.

INTRODUCTION: The superficial and deep parasternal intercostal plane (DPIP) blocks are two new blocks for thoracic pain. There are limited cadaveric studies evaluating the dye spread with these blocks. In this study, we examined the dye spread of an ultrasound-guided DPIP block in a human cadaveric model. METHODS: Five ultrasound-guided DPIP blocks were performed in four unembalmed human cadavers using an in-plane approach with a linear transducer oriented in a transverse plane adjacent to the sternum. Twenty milliliters of 0.1% methylene blue were injected between ribs 3 and 4 into the plane deep to the internal intercostal muscles and superficial to the transversus thoracis muscle layer. The chest muscles were dissected, and the extent of dye spread was documented in both cephalocaudal and mediolateral directions. RESULTS: The transversus thoracis muscle slips were stained in all cadavers from 4 to 6 levels. Intercostal nerves were dyed in all specimens. Four levels of intercostal nerves were dyed in each specimen with variability in number of levels stained above and below the level of the injection. CONCLUSIONS: The DPIP block spreads along the tissue plane above the transversus thoracis muscles to multiple levels to dye the intercostal nerves in this cadaver study. This block may be of clinical value for analgesia in anterior thoracic surgical procedures.

Attitudes and Perception of the REFLECT Communication Curriculum for Clinical Oncology Graduate Medical Education.

Communication and interpersonal skills are essential components of oncology patient care. The REFLECT (Respect, Empathy, Facilitate Effective Communication, Listen, Elicit Information, Compassion, and Teach Others) curriculum is a novel framework to improve and refine physician/patient interactions for oncology graduate medical trainees. We seek to evaluate the attitudes and perceptions of the REFLECT communication curriculum among oncology trainees. Seven-question and 8-question Likert scale surveys (1 = not beneficial and 5 = beneficial) were distributed to resident/fellow participants and faculty mentors, respectively. Questions asked trainees and faculty about their perceptions of improvement in communication, handling of stressful situations, the value of the curriculum, and overall impression of the curriculum. Descriptive statistics determined the survey's baseline characteristics and response rates. Kruskal-Wallis rank sum tests were used to compare the distribution of continuous variables. Thirteen resident/fellow participants completed the participant survey. Six (43.6%) Radiation Oncology trainees and 7 (58.3%) Hematology/Oncology fellows completed the trainee survey. Eight (88.9%) Radiation Oncologists and 1 (11.1%) Medical Oncologist completed the observer survey. Faculty and trainees generally felt that the curriculum increased communication skills. Faculty responded more favorably to the program's impact on communication skills (median 5.0 vs. 4.0, p = 0.008). Faculty were more assertive about the curriculum's capabilities to improve a learner's ability to handle stressful situations (median 5.0 vs. 4.0, p = 0.003). Additionally, faculty had a more favorable overall impression of the REFLECT curriculum than the residents/fellows (median 5.0 vs. 4.0, p < 0.001). Radiation Oncology residents felt more strongly that the curriculum enhanced their ability to handle stressful topics, compared to Heme/Onc fellows (median 4.5 vs. 3.0, range 1-5, p = 0.379). Radiation Oncology trainees felt more consistently that the workshops improved their communication skills, compared to Heme/Onc fellows (median 4.5 vs. 3.5, range 1-5, p = 0.410). The overall impression between Rad Onc resident and Heme/Onc fellows was similar (median 4.0, p = 0.586). Conclusions: Overall, the REFLECT curriculum enhanced communication skills of trainees. Oncology trainees and faculty physicians feel that the curriculum was beneficial. As interactive skills and communication is critical to build positive interactions, further work is needed to improve the REFLECT curriculum.

Gender bias in medical education: A scoping review.

PURPOSE: This scoping review summarises five decades of research on gender bias in subjective performance evaluations of medical trainees. METHOD: A medical librarian searched PubMed, Ovid Embase, Scopus, Web of Science and Cochrane DBSR in June 2020. Two researchers independently reviewed each abstract to determine if it met inclusion criteria (original research article investigating gender bias in subjective medical trainee evaluations by staff). References from selected articles were also reviewed for inclusion. Data were extracted from the articles, and summary statistics were performed. RESULTS: A total of 212 abstracts were reviewed, and 32 met criteria. Twenty (62.5%) evaluated residents, and 12 (37.5%) studied medical students. The majority of studies on residents were Internal Medicine (n = 8, 40.0%) and Surgery (n = 7, 35.0%). All studies were performed in North America and were either retrospective or observational. Nine (28.0%) were qualitative, and 24 (75.0%) were quantitative. The majority of studies were published in the last decade (n = 21, 65.6%). Twenty (62.5%) studies documented gender bias, of which 11 (55%) found that males received higher quantitative performance evaluations and 5 (25%) found that females received higher evaluation scores. The remaining 4 (20%) reported gender differences in qualitative evaluations. CONCLUSIONS: Most studies detected gender bias in subjective performance evaluations of medical trainees, with a majority favouring males. There is a paucity of studies on bias in medical education with a lack of standardised approach to investigating bias.

Do bone elasticity and postmortem interval affect forensic fractographic analyses?

Forensic fractographic features of bone reliably establish crack propagation in perimortem injuries. We investigated if similar fracture surface features characterize postmortem fractures. Experimentally induced peri- and postmortem fractures were used to assess if fractographic features vary as bone elasticity decreases during the postmortem interval (PMI). Thirty-seven unembalmed, defleshed human femoral shafts from males and females aged 33-81 years were fractured at varying PMIs with a drop test frame using a three-point bending setup and recorded with a high-speed camera. Vital statistics, cause of death, PMI length, temperature, humidity, collagen percentage, water loss, fracture energy, and fractography scores were recorded for each sample. Results showed that fractographic features associated with perimortem fractures were expressed in PMIs up to 40,600 accumulated degree hours (ADH), or 60 warm weather days. Hackle was the most consistently expressed feature, occurring in all fractures regardless of ADH. The most variable characteristics were wake features (78.4%) and arrest ridges (70.3%). Collagen percentage did not correlate strongly with ADH (r = -0.04, p = 0.81); however, there was a strong significant correlation between ADH and water loss (r = 0.74, p < 0.001). Multinomial logistic regression showed no association between fractographic feature expression and ADH or collagen percentage. In conclusion, forensic fractographic features reliably determine initiation and directionality of crack propagation in experimentally induced PMIs up to 40,600 ADH, demonstrating the utility of this method into the recent postmortem interval. This expression of reliable fractographic features throughout the early PMI intimates these characteristics may not be useful standalone features for discerning peri- versus postmortem fractures.

Evaluating expertise in forensic anthropology.

The medicolegal system relies on the ability of experts and non-experts alike to make judgments about expertise and use those judgments to reach consequential decisions. Given the lack of standard criteria, mandatory certification, or licensure for establishing expertise required to practice forensic anthropology and testify as an expert witness, we sought to understand how individuals assess and identify expertise in forensic anthropology by using a social science tool called the Imitation Game. This tool assesses immersion in a specific area of study via discourse, with the premise that some individuals lacking expertise themselves imitate or attempt to pass as experts. For this project we recruited volunteers with varying expertise in forensic anthropology to participate in interviews which asked questions about the practice and structure of the discipline. Those interviews were transcribed, anonymized, and evaluated by other recruited individuals with varying expertise in forensic anthropology. Results found that judges who were experts in forensic anthropology performed better than non-expert judges in determining who was not an expert in forensic anthropology based on their anonymized responses; however, nearly half of the non-experts were still able to pass as experts in forensic anthropology. The difficulties in assessing expertise based on discourse interactions demonstrates the value and need for well-defined credentials and mandatory certification to practice forensic anthropology. This study demonstrates that accurately identifying expertise in forensic anthropology may be challenging for both experts and non-experts, especially when relying solely on interactional expertise rather than formal assessments of competency which directly elucidate contributory expertise.

Evaluating two approaches to the erector spinae plane block: an anatomical study.

BACKGROUND AND OBJECTIVES: Studies show variable spread with thoracic erector spinae plane (ESP) injections. Injection sites vary from lateral end of the transverse process (TP) to 3 cm from the spinous process, with many not describing the precise site of injection. This human cadaveric study examined dye spread of ultrasound-guided thoracic ESP block at two needle locations. METHODS: Ultrasound-guided ESP blocks were performed on unembalmed cadavers. Methylene blue (20 mL, 0.1%) was injected in the ESP at the medial TP at level T5 (medial transverse process injection (MED), n=7) and the lateral end of the TP between T4 and T5 (injection between transverse processes (BTWN), n=7). The back muscles were dissected, and the cephalocaudal and medial-lateral dye spread documented. RESULTS: Dye spread cephalocaudally from C4-T12 in the MED group and C5-T11 in the BTWN group, and laterally to the iliocostalis muscle in five MED injections and all BTWN injections. One MED injection reached serratus anterior. Dorsal rami were dyed in five MED and all BTWN injections. Dye spread to the dorsal root ganglion and dorsal root in most injections, though more extensively in the BTWN group. The ventral root was dyed in 4 MED and 6 BTWN injections. Epidural spread in BTWN injections ranged from 3 to 12 levels (median: 5 levels), with contralateral spread in two cases and intrathecal spread in five injections. Epidural spread in MED injections was less extensive (median (range): 1 (0-3) levels); two MED injections did not enter the epidural space. CONCLUSION: An ESP injection administered between TPs exhibits more extensive spread than a medial TP injection in a human cadaveric model.

Evaluating the Anatomic Spread of Selective Nerve Scalp Blocks Using Methylene Blue: A Cadaveric Analysis.

BACKGROUND: The modern scalp block consists of local anesthesia injections that target the supraorbital, supratrochlear, zygomaticotemporal, auriculotemporal, and greater and lesser occipital nerves. Limited data exist on the local anesthetic spread that occurs with this technique. This study examines the extent of the spread of a scalp block using methylene blue in a cadaveric model. METHODS: A traditional landmark-based scalp block was performed on 6 unembalmed human cadavers using 25-G, 1.5-inch needles to inject 1 to 2 mL of methylene blue 0.1% at each nerve bilaterally; a total volume of 20 mL was injected. The cadavers were then dissected, and the spread of injectate was measured and recorded. RESULTS: All the nerves required for analgesic coverage were appropriately stained by the injections, except for in 2 specimens where the lesser occipital nerve could not be identified. The zygomatic (stained in 2 of 8 specimens) and temporal (stained in 5 of 8 specimens) branches of the facial nerve were stained as a result of the zygomaticotemporal and/or auriculotemporal injections. Tracking from the zygomatic injection site was noted as far inferior as the temporalis muscle attachments on the mandible. CONCLUSIONS: This cadaveric study confirms that the landmark-based technique for scalp blocks consistently stained all 6 nerves involved in scalp innervation. There was significant unintentional spread to the branches of the facial nerve when using the landmark technique.

Evaluating the spread of costoclavicular brachial plexus block: an anatomical study.

BACKGROUND AND OBJECTIVES: The costoclavicular brachial plexus block is performed deep and posterior to the midpoint of the clavicle. There are limited data evaluating the spread of the costoclavicular brachial plexus block. We performed a cadaveric study to evaluate the spread of injectate after a costoclavicular brachial plexus block. METHODS: Five ultrasound-guided costoclavicular block injections were performed with 20 mL of 0.1% methylene blue. The brachial plexus and its branches were dissected from the level of C4 to the lower axilla. The extent of dye spread was recorded including spread to the phrenic nerve, suprascapular nerve, roots, trunks, divisions, cords and terminal branches of the brachial plexus. RESULTS: The dye extended cephalad to the level of the cricoid cartilage in two of the five injections; three injections had dye extending 0.75 cm, 1.5 cm and 2 cm caudad to the level of the cricoid cartilage, respectively. The C7, C8 and T1 nerve roots were stained in all injections. The dye did not extend cephalad to the C5 and C6 nerve roots. All trunks, cords and divisions of the brachial plexus were stained, as was the suprascapular nerve. There was no spread of dye to the phrenic nerve in any of the specimens. CONCLUSIONS: This cadaveric study demonstrates that ultrasound-guided injection in the costoclavicular space spreads cephalad to the brachial plexus in the supraclavicular space, consistently reaching the suprascapular nerve and all trunks and cords of the brachial plexus, while sparing the phrenic nerve.

STEM crisis teaching: Curriculum design with e-learning tools.

The COVID-19 pandemic and subsequent social distancing protocols have accelerated the shift to online teaching across the globe. In Science, Technology, Engineering, and Mathematics (STEM) programs this means a shift from face-to-face laboratory instruction to self-directed learning with e-learning tools. Unfortunately, selecting and integrating an e-learning tool into a curriculum can be daunting. This article highlights key questions and practical suggestions instructors should consider in choosing the most effective option for their course and learners.

Evaluating the extent of lumbar erector spinae plane block: an anatomical study.

BACKGROUND AND OBJECTIVES: The erector spinae plane (ESP) block is a relatively new interfascial block technique. Previous cadaveric studies have shown extensive cephalocaudal spread with a single ESP injection at the thoracic level. However, little data exist for lumbar ESP block. The objective of this study was to examine the anatomical spread of dye following an ultrasound-guided lumbar ESP block in a human cadaveric model. METHODS: An ultrasound-guided ESP block was performed in unembalmed human cadavers using an in-plane approach with a curvilinear transducer oriented longitudinally. 20 mL of 0.166% methylene blue was injected into the plane between the distal end of the L4 transverse process and erector spinae muscle bilaterally in four specimens and unilaterally in one specimen (nine ESP blocks in total). The superficial and deep back muscles were dissected, and the extent of dye spread was documented in both cephalocaudal and medial-lateral directions. RESULTS: There was cephalocaudal spread from L3 to L5 in all specimens with extension to L2 in four specimens. Medial-lateral spread was documented from the multifidus muscle to the lateral edge of the thoracolumbar fascia. There was extensive dye in and around the erector spinae musculature and spread to the dorsal rami in all specimens. There was no dye spread anteriorly into the dorsal root ganglion, ventral rami, or paravertebral space. CONCLUSIONS: A lumbar ESP injection has limited craniocaudal spread compared with injection in the thoracic region. It has consistent spread to dorsal rami, but no anterior spread to ventral rami or paravertebral space.

Anatomical Sciences Education Among Biological Anthropology Graduates: a Solution to the Dearth of Anatomy Educators?

The need for anatomical knowledge is increasingly in demand as new medical and allied-health professions programs continue to open, but there is a growing dearth of educators with formal training in the anatomical sciences. Several sources for anatomy faculty have been suggested, including surgeons, but few have considered a more obvious, alternative approach to this shortage: hiring qualified faculty from other PhD departments/programs whose graduates receive formal training in anatomy, including biological anthropologists. This study surveyed 305 biological anthropology graduates to assimilate information about the nature and extent of training among biological anthropology graduates in the core anatomy disciplines (anatomy, histology, embryology, histology, neuroanatomy), and to determine whether biological anthropology graduates value and apply anatomy training. Only 36% of PhDs reported that anatomy was a required course, but 72% of PhD graduates took an anatomy course (usually gross anatomy with a human cadaveric dissection laboratory). Histology, embryology, and neuroanatomy also were not required to obtain a PhD, though some of this material was covered during the anatomy course, and some students opted to take these courses as electives. Forty-five percent of PhD students reported teaching experience in gross anatomy courses with cadaveric dissection. Ninety-four percent of biological anthropology PhD graduates are prepared to teach human osteology, and 48% are comfortable teaching gross anatomy. Biological anthropology graduates bring unique expertise, training, and research experience to medical education programs, and many are well-suited to fill the growing number of anatomy faculty positions.

Data for validation of osteometric methods in forensic anthropology.

Many techniques in forensic anthropology employ osteometric data, although little work has been done to investigate the intrinsic error in these measurements. These data were collected to quantify the reliability of osteometric data used in forensic anthropology research and case analyses. Osteometric data (n = 99 measurements) were collected on a random sample of William M. Bass Donated Collection skeletons (n = 50 skeletons). Four observers measured the left elements of 50 skeletons. After the complete dataset of 99 measurements was collected on each of the 50 skeletons, each observer repeated the process for a total of four rounds. The raw data is available on Mendeley Data ( DCP Osteometric Data, Version 1. DOI: 10.17632/6xwhzs2w38.1). An example of the data analyses performed to evaluate and quantify observer error is provided for the variable GOL (maximum cranial length); these analyses were performed on each of the 99 measurements. Two-way mixed ANOVAs and repeated measures ANOVAs with pairwise comparisons were run to examine intraobserver and interobserver error, and relative and absolute technical error of measurement (TEM) was calculated to quantify the observer variation. This data analysis supported the dissemination of a free laboratory manual of revised osteometric definitions (Data Collection Procedures 2.0[1], pdf available at https://fac.utk.edu/wp-content/uploads/2016/03/DCP20_webversion.pdf) and an accompanying instructional video (https://www.youtube.com/watch?v=BtkLFl3vim4). This manual is versioned and updatable as new information becomes available. Similar validations of scientific data used in forensic methods would support the ongoing effort to establish valid and reliable methods and protocols for proficiency testing, training, and certification.

Error quantification of osteometric data in forensic anthropology.

This study evaluates the reliability of osteometric data commonly used in forensic case analyses, with specific reference to the measurements in Data Collection Procedures 2.0 (DCP 2.0). Four observers took a set of 99 measurements four times on a sample of 50 skeletons (each measurement was taken 200 times by each observer). Two-way mixed ANOVAs and repeated measures ANOVAs with pairwise comparisons were used to examine interobserver (between-subjects) and intraobserver (within-subjects) variability. Relative technical error of measurement (TEM) was calculated for measurements with significant ANOVA results to examine the error among a single observer repeating a measurement multiple times (e.g. repeatability or intraobserver error), as well as the variability between multiple observers (interobserver error). Two general trends emerged from these analyses: (1) maximum lengths and breadths have the lowest error across the board (TEM<0.5), and (2) maximum and minimum diameters at midshaft are more reliable than their positionally-dependent counterparts (i.e. sagittal, vertical, transverse, dorso-volar). Therefore, maxima and minima are specified for all midshaft measurements in DCP 2.0. Twenty-two measurements were flagged for excessive variability (either interobserver, intraobserver, or both); 15 of these measurements were part of the standard set of measurements in Data Collection Procedures for Forensic Skeletal Material, 3rd edition. Each measurement was examined carefully to determine the likely source of the error (e.g. data input, instrumentation, observer's method, or measurement definition). For several measurements (e.g. anterior sacral breadth, distal epiphyseal breadth of the tibia) only one observer differed significantly from the remaining observers, indicating a likely problem with the measurement definition as interpreted by that observer; these definitions were clarified in DCP 2.0 to eliminate this confusion. Other measurements were taken from landmarks that are difficult to locate consistently (e.g. pubis length, ischium length); these measurements were omitted from DCP 2.0. This manual is available for free download online (https://fac.utk.edu/wp-content/uploads/2016/03/DCP20_webversion.pdf), along with an accompanying instructional video (https://www.youtube.com/watch?v=BtkLFl3vim4).

A Decision Tree for Nonmetric Sex Assessment from the Skull.

This study uses five well-documented cranial nonmetric traits (glabella, mastoid process, mental eminence, supraorbital margin, and nuchal crest) and one additional trait (zygomatic extension) to develop a validated decision tree for sex assessment. The decision tree was built and cross-validated on a sample of 293 U.S. White individuals from the William M. Bass Donated Skeletal Collection. Ordinal scores from the six traits were analyzed using the partition modeling option in JMP Pro 12. A holdout sample of 50 skulls was used to test the model. The most accurate decision tree includes three variables: glabella, zygomatic extension, and mastoid process. This decision tree yielded 93.5% accuracy on the training sample, 94% on the cross-validated sample, and 96% on a holdout validation sample. Linear weighted kappa statistics indicate acceptable agreement among observers for these variables. Mental eminence should be avoided, and definitions and figures should be referenced carefully to score nonmetric traits.

Computerized reconstruction of fragmentary skeletal remains.

This research presents a new software, "Fragmento", for accurate analyses of fragmentary human skeletal remains and facilitation of three-dimensional (3D) fragmentary matching and full bone reconstruction. The framework utilizes the power of statistical bone atlases to create 3D templates for bone matching and to interpolate missing anatomy for full bone reconstruction. Developed tool has enhanced features allowing the user to visualize, review and scale all scanned skeletal remains within a 3D statistical template, merging accepted registered elements to provide a fully reconstructed bone. A three stage validation was performed on Fragmento: Stages I and II used simulated fragmentary data which was compared to full bones with an error less than 3mm; Stage III compared output from geographic information system (GIS) software with comparable results. This validation process demonstrates the robustness and utility of Fragmento as tool for 3D fragmentary bone matching and full bone reconstruction.

Impact of Anatomy Boot Camp on Students in a Medical Gross Anatomy Course.

Lincoln Memorial University-DeBusk College of Osteopathic Medicine (LMU-DCOM) offers an optional three-week summer Anatomy Boot Camp course (ABC) to facilitate students' transition into medical school and promote retention of anatomy subject matter. The pre-matriculation program is a supplemental instruction course that utilizes a small group learning format. Boot camp instruction is led by teaching assistants and two anatomy professors. Enrollees gain early exposure to Medical Gross Anatomy (MGA) course subject matter, which is taught in the fall semester, and learn study skills necessary to excel in medical school. No grade is assigned for the course, therefore participants can study without the fear of potentially affecting grades. This study evaluates the effectiveness of the LMU-DCOM ABC course using data from four consecutive summers. Independent two-sample t-tests were used to compare ABC to non-ABC students for the following variables: incoming grade point average (GPA) and Medical College Admission Test® (MCAT®) scores, MGA written and laboratory practical examination grades, and final MGA course grade. Additionally, a 26-question survey was administered to 2012-2014 boot camp participants. There were no significant differences in incoming GPA and MCAT scores. However, boot campers scored significantly higher on the first two lecture and laboratory examinations (P < 0.05) for each year of the study. Thereafter scores varied less, suggesting a faster head start for boot camp participants. Mean MGA final grade was on average 3% higher for the boot camp cohort. The survey feedback supports that the ABC course assists with the academic and social transition into medical school. Anat Sci Educ 10: 215-223. © 2016 American Association of Anatomists.

Changes in Clavicle Length and Maturation in Americans: 1840-1980.

Secular changes refer to short-term biological changes ostensibly due to environmental factors. Two well-documented secular trends in many populations are earlier age of menarche and increasing stature. This study synthesizes data on maximum clavicle length and fusion of the medial epiphysis in 1840-1980 American birth cohorts to provide a comprehensive assessment of developmental and morphological change in the clavicle. Clavicles from the Hamann-Todd Human Osteological Collection (n = 354), McKern and Stewart Korean War males (n = 341), Forensic Anthropology Data Bank (n = 1,239), and the McCormick Clavicle Collection (n = 1,137) were used in the analysis. Transition analysis was used to evaluate fusion of the medial epiphysis (scored as unfused, fusing, or fused). Several statistical treatments were used to assess fluctuations in maximum clavicle length. First, Durbin-Watson tests were used to evaluate autocorrelation, and a local regression (LOESS) was used to identify visual shifts in the regression slope. Next, piecewise regression was used to fit linear regression models before and after the estimated breakpoints. Multiple starting parameters were tested in the range determined to contain the breakpoint, and the model with the smallest mean squared error was chosen as the best fit. The parameters from the best-fit models were then used to derive the piecewise models, which were compared with the initial simple linear regression models to determine which model provided the best fit for the secular change data. The epiphyseal union data indicate a decline in the age at onset of fusion since the early twentieth century. Fusion commences approximately four years earlier in mid- to late twentieth-century birth cohorts than in late nineteenth- and early twentieth-century birth cohorts. However, fusion is completed at roughly the same age across cohorts. The most significant decline in age at onset of epiphyseal union appears to have occurred since the mid-twentieth century. LOESS plots show a breakpoint in the clavicle length data around the mid-twentieth century in both sexes, and piecewise regression models indicate a significant decrease in clavicle length in the American population after 1940. The piecewise model provides a slightly better fit than the simple linear model. Since the model standard error is not substantially different from the piecewise model, an argument could be made to select the less complex linear model. However, we chose the piecewise model to detect changes in clavicle length that are overfitted with a linear model. The decrease in maximum clavicle length is in line with a documented narrowing of the American skeletal form, as shown by analyses of cranial and facial breadth and bi-iliac breadth of the pelvis. Environmental influences on skeletal form include increases in body mass index, health improvements, improved socioeconomic status, and elimination of infectious diseases. Secular changes in bony dimensions and skeletal maturation stipulate that medical and forensic standards used to deduce information about growth, health, and biological traits must be derived from modern populations.

The lateral clavicular epiphysis: fusion timing and age estimation.

This study utilizes a forensic autopsy sample of twentieth century American Whites (the McCormick Clavicle Collection) to describe the morphology, variation, and fusion timing of the lateral clavicle epiphysis. Clavicles from individuals between 11 and 25 years at the time of death were used to document fusion of the lateral epiphysis (n= 133, 38 females and 95 males). The lateral epiphysis was scored as unfused, fusing, or fused. A linear weighted kappa indicates that this scoring method is highly replicable with almost perfect inter-rater agreement (kappa = 0.849), according to a widely used standard for assessing kappa values. Transition analysis, or probit regression, was employed to quantify fusion timing of the lateral epiphysis. The transition from "unfused" to "fusing" is most likely to occur at 16.5 years in females and 17.5 years in males. The transition from "fusing" to "fused" occurs at age 21 in females and age 20 in males. The earliest age at which fusion began was 15 years (n = 1), but the majority began fusing between 17 and 20 years. Most individuals (98.5 % of the sample) aged >24 years had fused lateral epiphyses. The epiphysis assumes one of two forms: (1) a separate bony flake fusing to the diaphysis or (2) a mound of bone glazing/smoothing over the diaphyseal surface. As socioeconomic status has been cited as the most influential variable on skeletal maturation rates, the fusion ages offered here should not be applied to populations with a socioeconomic status different from the greater US population.