Epidemiological Practice Research Articles

Is the Measurement of Blood Pressure by Automatic Monitor in the South American Pediatric Population Accurate? SAYCARE Study.

This study aimed to test the validity of an automatic oscillometric device to measure the blood pressure (BP) in children (n = 191) and adolescents (n = 127) aged 3 to 18 years. Systolic BP (SBP) and diastolic BP (DBP) levels were measured simultaneous by automatic device and mercury column with Y-connection. To verify the validity, Bland-Altman plots and limits of agreement of 95% (95% LOA), specificity and sensitivity of the device, and the grade of British Hypertension Society (BHS) criteria were used. The monitor measurements demonstrated lower measurement bias (mean difference [95% LOA]): 1.4 (-9.9 to 12.8) mmHg in children and 4.3 (-7.8 to 16.5) mmHg in adolescents for SBP. For DBP, it was 2.2 (-7.4 to 11.7) mmHg in children and 1.4 (-8.4 to 11.1) mmHg in adolescents. The sensitivity in children was 21.4 (95% CI = 16.3-26.6), and in adolescents, it was 20.0 (95% CI = 13.2-26.8); the specificity was 95.9 (95% CI = 93.4-98.4) in children and 100.0 (95% CI = 100.0-100.0) in adolescents. The monitor-tested ratings are Grade B for SBP in children and SBP and DBP in adolescents and Grade C for DBP in children. The automatic monitor presented high values of specificity and lower values of sensitivity to the diagnosis of HBP; however, it can be considered accurate (lower measurement bias) and valid for epidemiological and clinical practice in accordance with BHS criteria.

Responsible Epidemiologic Research Practice: a guideline developed by a working group of the Netherlands Epidemiological Society

ObjectivesTo develop a guideline on Responsible Epidemiologic Research Practice that will increase value and transparency, increase the accountability of the epidemiologists, and reduce research waste. SettingA working group of the Netherland Epidemiological Society was given the task of developing a guideline that would meet these objectives. Several publications about the need to prevent Detrimental Research Practices triggered this work. Among these were a series in the Lancet on research waste and a subsequent series on transparency in the Journal of Clinical Epidemiology. The reputation and trust in epidemiologic research is still high, and the Netherlands Epidemiological Society wishes to keep it that way. The guideline deals with how epidemiologic research should be conducted, archived, and disclosed. It does not deal with the more technical aspects, such as required sample size, choice of study design, and so forth. The guideline describes each step in the process of conducting an epidemiologic study, from the first idea to the ultimate publication and beyond. MethodsThe working group reviewed the literature on responsible research conduct, including the various existing codes of conduct. It applied the general principles from these codes to the elements of an epidemiologic study and formulated specific recommendations for each of these. Next step was to draft the guideline. Preceding the 2016 annual national epidemiology conference in Wageningen, a preconference was organized to discuss the draft guideline and to assess support. Support was clearly present, and the provided recommendations were incorporated into the draft guideline. In March 2017, a draft version of the guideline was sent to all 1,100 members of the society with the request to review and provide comments. All received responses were positive, and some minor additions were made. The Responsible Epidemiologic Research Practice guideline has now been approved by the board of the Netherlands Epidemiological Society. ConclusionWith the Responsible Epidemiologic Research Practice guideline, we hope to contribute to better research practices in epidemiology but perhaps also in adjacent disciplines.

Ethnicity and HIV vulnerabilities among men who have sex with men in China

ABSTRACTEthnic affiliation can define sociocultural boundaries and contribute to the HIV vulnerabilities faced by men who have sex with men (MSM). This study investigated the influence of ethnic affiliation on HIV vulnerabilities among MSM in North China. Our study analyzed a cross-sectional survey of MSM (n = 398) in two major North China cities. We examined associations between ethnic affiliation and (a) HIV status, (b) sexual behaviors and experiences, and (c) substance use. Compared to ethnic majority Han MSM: MSM belonging to ethnic minority groups of South China had significantly greater odds of HIV infection (AOR: 7.40; 95% CI: 2.33–23.47) and experience of forced sex (AOR: 3.27; 95% CI: 1.12–9.52). Compared to ethnic majority Han MSM, Ethnic Hui MSM had significantly lower odds of condomless anal sex (AOR: 0.41; 95% CI: 0.21–0.82) and significantly greater odds of circumcision (AOR: 2.62; 95% CI: 1.24–5.51). HIV prevalence and riskier sexual behaviors among MSM in China appear to vary significantly by ethnic affiliation. Current epidemiological practices of aggregating all ethnic minority groups in China into a single category may be masking important interethnic differences in HIV risk, and precluding opportunities for more culturally appropriate interventions.

Evaluating patient epidemiology and clinical practice on the outcome of patients admitted with skull fractures secondary to assault

Objectives: Patients whom incur skull fractures secondary to assault are a common referral to the Department of Neurosurgery at Dr. George Mukhari Academic Hospital in Pretoria, South Africa. Our study aimed to statistically evaluate patient epidemiology and our clinical practice in relation to patient outcome. Methods: A retrospective chart review of 246 consecutively admitted patients with skull fractures secondary to assault from January 2015-December 2016 was performed. Medical records were analyzed for patient demographics and key aspects of our clinical practice which included patient age, gender, employment status, type of referral, days from injury until admission, mechanism of injury, severity of head injury, CT scan findings, days from admission until operative intervention, type of surgery performed, in-patient sepsis rate, length of hospital stay and Glasgow Outcome Score. Results: On univariate analysis the variables that demonstrated an increased chance of a patient having a favorable outcome were having a mean age of 30 years (p=0.01), being referred from a local clinic (p<0.001), being assaulted with a brick (p=0.02), having a mild head injury (p<0.001), having an extradural haematoma (p<0.001), having a craniectomy with/without a dural repair performed (p<0.001), and having a mean length of hospital stay of 9 days (p<0.05). The variables associated with a patient having an unfavorable outcome were being above the age of 40 years (p=0.003), being referred from the scene of the assault (p<0.001), being assaulted by the community (p=0.02), having a severe head injury (p<0.001), having an acute subdural haematoma or contusion (p<0.001), having a decompressive craniectomy performed (p<0.001) and having a mean length of hospital stay of 13-18 days (p<0.05). Conclusion: Our study demonstrated that the majority of the significant prognostic variables were determined in the pre-hospital setting. Our study highlights the importance of primary prevention as the major consideration that should be targeted to prevent the morbidity and mortality associated with this social problem

Identifying the source of food-borne disease outbreaks: An application of Bayesian variable selection.

Early identification of contaminated food products is crucial in reducing health burdens of food-borne disease outbreaks. Analytic case-control studies are primarily used in this identification stage by comparing exposures in cases and controls using logistic regression. Standard epidemiological analysis practice is not formally defined and the combination of currently applied methods is subject to issues such as response misclassification, missing values, multiple testing problems and small sample estimation problems resulting in biased and possibly misleading results. In this paper, we develop a formal Bayesian variable selection method to account for misclassified responses and missing covariates, which are common complications in food-borne outbreak investigations. We illustrate the implementation and performance of our method on a Salmonella Thompson outbreak in the Netherlands in 2012. Our method is shown to perform better than the standard logistic regression approach with respect to earlier identification of contaminated food products. It also allows relatively easy implementation of otherwise complex methodological issues.

Epidemiology and Clinical Management of Traumatic Spine Injuries at a Major Government Hospital in Cambodia.

Study DesignCross sectional study.PurposeTo characterize the pattern of injury, describe the current clinical management, and determine the outcomes in traumatic spine injury (TSI) patients presenting to a major government hospital in Phnom Penh, Cambodia.Overview of LiteratureThere is a paucity of literature on epidemiology or current clinical practices for TSIs in Cambodia. The findings from this study can thus serve as a valuable resource for future progress in treating TSIs in low-income countries.MethodsThis study was a cross-sectional study of TSI patients admitted to Preah Kossamak Hospital in Phnom Penh, Cambodia. Demographics, cause of spinal injury, spinal level of injury, surgical procedures and techniques, complications, and American Spinal Injury Association (ASIA) grades were recorded and analyzed.ResultsEighty patients were admitted with TSI between October 2013 and June 2014. Falls from heights were the most common cause of TSI, followed by road traffic accidents. 78% of the admitted patients underwent at least one surgical procedure. Without intraoperative imaging, 4 patients (6%) had wrong level surgery, and 1 patient (2%) had misplacement of pedicle screws. Sacral decubitus ulcers were the most common non-surgically related complication. Antibiotics were administered to >90% of patients. There were no in-hospital mortalities. Of the 60 spinal cord injury (SCI) patients, 32% (19/60) showed improvement in their ASIA grade at the time of discharge, and 52% (31/60) showed no change. At follow-up, 32% (19/60) of SCI patients reported improvement, and 8% (5/60) reported no change. However, 36 SCI patients (60%) were lost to follow-up.ConclusionsDespite technological limitations, outcomes of TSI patients in Cambodia appear favorable with evidence of clinical improvement and low mortality.

Epidemiology, associated burden, and current clinical practice for the diagnosis and management of Alzheimer's disease in Japan.

The burden of dementia in Japan is large and growing. With the world’s fastest aging population, it is estimated that one in five elderly people will be living with dementia in Japan by 2025. The most common form of dementia is Alzheimer’s disease (AD), accounting for around two-thirds of dementia cases. A systematic review was conducted to examine the epidemiology and associated burden of AD in Japan and to identify how AD is diagnosed and managed in Japan. English and Japanese language databases were searched for articles published between January 2000 and November 2015. Relevant Japanese sources, clinical practice guideline registers, and reference lists were also searched. Systematic reviews and cohort and case–control studies were eligible for inclusion, with a total of 60 studies included. The most recent national survey conducted in six regions of Japan reported the mean prevalence of dementia in people aged ≥65 years to be 15.75% (95% CI: 12.4, 22.2%), which is much higher than the previous estimated rate of 10% in 2010. AD was confirmed as the predominant type of dementia, accounting for 65.8% of all cases. Advancing age and low education were the most consistently reported risk factors for AD dementia. Japanese guidelines for the management of dementia were released in 2010 providing specific guidance for AD about clinical signs, image findings, biochemical markers, and treatment approaches. Pharmacotherapies and non-pharmacotherapies to relieve cognitive symptoms were introduced, as were recommendations to achieve better patient care. No studies reporting treatment patterns were identified. Due to population aging and growing awareness of AD in Japan, health care expenditure and associated burden are expected to soar. This review highlights the importance of early detection, diagnosis, and treatment of AD as strategies to minimize the impact of AD on society in Japan.

A review of the impact of shift-work on cancer: summary of the evidence for practitioners

AbstractShift work that involves disruption to the body’s circadian rhythm is classified as probably carcinogenic to humans based on limited evidence in humans and sufficient evidence in experimental animals. This article draws together the available information from the epidemiological, mechanistic and health and safety practice research to provide advice for practitioners. There is evidence that the increase in breast cancer risk amongst women who have worked night shifts is relatively modest and we cannot exclude the possibility that there is no cancer risk. If a causal association exists, the most likely mechanism is night time suppression of the production of the hormone melatonin. However, the observed increased risk of breast cancer amongst night shift workers may be due to higher prevalence of obesity and other lifestyle risks in this group of women. Current health and safety policies for shift work generally do not address cancer risks. Employers should develop a workplace policy for night work t...

VAPING KNOWLEDGE, ATTITUDE AND PRACTICE AMONGST GENERAL PUBLIC IN MALAYSIA

RespirologyVolume 22, Issue S3 p. 50-50 Environmental and Occupational Health / Epidemiology VAPING KNOWLEDGE, ATTITUDE AND PRACTICE AMONGST GENERAL PUBLIC IN MALAYSIA First published: 23 November 2017 https://doi.org/10.1111/resp.13206_121Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume22, IssueS3Supplement: 22nd Congress of the Asian Pacific Society of Respirology, International Convention Centre, Sydney, Australia, 23–26 November 2017November 2017Pages 50-50 RelatedInformation

The Ethics of Biomedical Big Data

The availability of diverse sources of data related to health and illness from various types of modern communication technology presents the possibility of augmenting medical knowledge, clinical care, and the patient experience. New forms of data collection and analysis will undoubtedly transform epidemiology, public health, and clinical practice, but what ethical considerations come in to play? With a view to analysing the ethical and regulatory dimensions of burgeoning forms of biomedical big data, Brent Daniel Mittelstadt and Luciano Floridi have brought together thirty scholars in an edited volume that forms part of Springer’s Law, Governance and Technology book series in a collection titled The Ethics of Biomedical Big Data. With eighteen chapters partitioned into six carefully devised sections, this volume engages with core theoretical, ethical, and regulatory challenges posed by biomedical big data.

Bridging the Gap in Implementation Science: Evaluating a Capacity-Building Program in Data Management, Analysis, Utilization, and Dissemination in Low- and Middle-Income Countries

Building capacity in implementation science within health programs is dependent on training in theory and practice of epidemiology, statistics, and research in addition to high self-efficacy toward application of training. This article describes a training program providing technical assistance to more than 300 health facilities in Kenya and Tanzania, its evaluation results, and its ability to improve participants' knowledge, competencies, and self-efficacy on data management, analysis, and dissemination among health care professionals. Two months prior to the training, participants (n = 98) were emailed a pre-course survey including 19 questions using a Likert-type response for planning the content of the workshop. Six to 12 weeks after the training, a post-course survey was emailed to all participants. Five different trainings were conducted indicating 5 participant cohorts. The questions posed involved course satisfaction, course impact on knowledge and skills, and self-efficacy in data analysis and utilization. Post-course survey results revealed that the participants had confidence in data analysis, which was significantly different from the pre-test results (0.05 α). Qualitative commentary complemented the findings of the impact of the workshop. Four manuscripts and 13 abstracts have been submitted post training. Results suggest that a short-term training program can achieve immediate gains in data and research self-efficacy among health care professionals. Although increasing self-efficacy is a necessary first step in developing skills, educators should engage in continuing education for sustainable dissemination practices. There is an urgent need to determine the current infrastructure to promote scientific dissemination. This will assist countries to produce better evidence to support their programs, policies, and overall health programs.

Novel Methods in Disease Biogeography: A Case Study with Heterosporosis.

Disease biogeography is currently a promising field to complement epidemiology, and ecological niche modeling theory and methods are a key component. Therefore, applying the concepts and tools from ecological niche modeling to disease biogeography and epidemiology will provide biologically sound and analytically robust descriptive and predictive analyses of disease distributions. As a case study, we explored the ecologically important fish disease Heterosporosis, a relatively poorly understood disease caused by the intracellular microsporidian parasite Heterosporis sutherlandae. We explored two novel ecological niche modeling methods, the minimum-volume ellipsoid (MVE) and the Marble algorithm, which were used to reconstruct the fundamental and the realized ecological niche of H. sutherlandae, respectively. Additionally, we assessed how the management of occurrence reports can impact the output of the models. Ecological niche models were able to reconstruct a proxy of the fundamental and realized niche for this aquatic parasite, identifying specific areas suitable for Heterosporosis. We found that the conceptual and methodological advances in ecological niche modeling provide accessible tools to update the current practices of spatial epidemiology. However, careful data curation and a detailed understanding of the algorithm employed are critical for a clear definition of the assumptions implicit in the modeling process and to ensure biologically sound forecasts. In this paper, we show how sensitive MVE is to the input data, while Marble algorithm may provide detailed forecasts with a minimum of parameters. We showed that exploring algorithms of different natures such as environmental clusters, climatic envelopes, and logistic regressions (e.g., Marble, MVE, and Maxent) provide different scenarios of potential distribution. Thus, no single algorithm should be used for disease mapping. Instead, different algorithms should be employed for a more informed and complete understanding of the pathogen or parasite in question.

Selecting Shrinkage Parameters for Effect Estimation: The Multi-Ethnic Study of Atherosclerosis.

We present a method for improving estimation in linear regression models in samples of moderate size, using shrinkage techniques. Our work connects the theory of causal inference, which describes how variable adjustment should be performed with large samples, with shrinkage estimators such as ridge regression and the least absolute shrinkage and selection operator (LASSO), which can perform better in sample sizes seen in epidemiologic practice. Shrinkage methods reduce mean squared error by trading off some amount of bias for a reduction in variance. However, when inference is the goal, there are no standard methods for choosing the penalty "tuning" parameters that govern these tradeoffs. We propose selecting the penalty parameters for these shrinkage estimators by minimizing bias and variance in future similar data sets drawn from the posterior predictive distribution. Our method provides both the point estimate of interest and corresponding standard error estimates. Through simulations, we demonstrate that it can achieve better mean squared error than using cross-validation for penalty parameter selection. We apply our method to a cross-sectional analysis of the association between smoking and carotid intima-media thickness in the Multi-Ethnic Study of Atherosclerosis (multiple US locations, 2000-2002) and compare it with similar analyses of these data.

Clinical practice of acute respiratory distress syndrome in Japan: A nationwide survey and scientific evidences

There has been limited information about epidemiology and clinical practice of acute respiratory distress syndrome (ARDS) in Japan. An invitation letter to the web-based survey was mailed to all 871 board certified hospitals of the Japanese Respiratory Society. The questionnaires were designed to collect data on epidemiology and clinical practice of ARDS, including diagnostic measures and therapeutics. Within 4 months of the survey period, valid responses were obtained from 296 (34%) hospitals. The incidence of ARDS was estimated to be 3.13 cases/100 hospital beds or 1.91 cases/ICU bed per year. The most frequent underlying disease was pneumonia (34%), followed by sepsis (29%). In hospitals with fewer ICU beds, pulmonologists tended to be in charge of management of ARDS patients. Routine diagnostic measures included computed tomography of the chest (69.6% of the hospitals) and Swan-Ganz catheterization was rarely performed for diagnosis. In 87.4% of the hospitals, non-invasive ventilation was applied to management of ARDS patients, especially those with mild disease. Prone positioning and extracorporeal membrane oxygenation (ECMO) for ARDS patients was more widely adopted in hospitals with larger numbers of ICU beds and intensivists. In 58.2% of the responding hospitals, corticosteroid was considered as a treatment option for ARDS, among which pulse therapy was routinely introduced to ARDS patients in 35.4%. The incidence of ARDS in Japan was estimated to be lower than that in the recent international study. The scale and equipment of hospitals and the number of intensivists might influence clinical practice of ARDS.

Social determination of the health-disease process: a critical look from the epidemiology of the 21st century

The so-called social determination is a key concept for Latin American Social Medicine (LASM). LASM criticizes epidemiology frequently, mainly because of its reductionist vision and its distance from social reality. This paper makes an opposite analysis, in other words, 21st century epidemiology criticizes LASM, using the disciplinary development in Colombia as an example. The history of Colombian epidemiology is reviewed, noting that it has not had sufficient development and that LASM tends to reject quantitative methods based on the epidemiological practices used four decades ago. Additionally, some developments of the quantitative methods used in epidemiology are reviewed, explaining that many of the limitations indicated by LASM have been overcome. In conclusion, LASM uses social determination as part of its leftist political platform; however, current quantitative methods and the 21st century theoretical developments in epidemiology show a pragmatic superiority, useful for solving current public health issues.

Lost in translation?

This rather unorthodox essay is a dialogue between an anthropologist and an epidemiologist, both of whom were involved with a large-scale collaborative ethnographic project exploring medical field studies, or ‘trial communities’, in western Kenya. Reflecting on their involvement with this project, the authors consider the pragmatics of what ‘collaboration’ represents in different disciplines and how it is enacted. The dialogue, which included a follow-up interview after the research was completed, highlights the expectations and tensions in such collaborative projects and offers the epidemiologist an opportunity to highlight the ideas, methods, and possibilities that he perceived as being ‘lost in translation’ between sociocultural anthropology and experimental medicine. We raise critical issues regarding the disjuncture between epidemiological and anthropological practices in research design, methods, epistemology, and collaboration, with the hopes of provoking more discussions regarding best practices in collaborative research projects.

CAPACIDADE DE INFERÊNCIA DIAGNÓSTICA DE ENFERMEIROS ESPECIALISTAS

Objective: To assess the capacity for diagnostic inference among specialist nurses. Method: Descriptive study, performed in July 2013, with five specialist nurses of the research group entitled Care and Epidemiology Practices in Health and Nursing. The diagnostic inference capacity was assessed through efficiency tests, false positive rate, false negative rate and trend analysis. The research was approved by the research ethics committee of the sponsoring institution, through the Protocol N°148.428. Results: Among the specialists evaluated for their diagnostic inference capacity, only two reached the desirable scores out of the four attributes evaluated. Conclusion: It is concluded that few specialist nurses obtained satisfactory results. Thus, it is necessary to develop learning strategies in their undergraduate studies and their continuing education for practitioners.

Building capacity in Clinical Epidemiology in Africa: experiences from Masters programmes

BackgroundTo describe and contrast programmatic offering of Clinical Epidemiology Masters programmes in Africa, to evaluate experiences of graduates and faculty, and assess if graduates are playing roles in research, practice and teaching of Clinical Epidemiology.MethodsWe searched and identified relevant programmes, reviewed programmatic documentation, interviewed convenors and surveyed graduates. Participants provided informed consent, interviews with faculty were recorded and transcribed for analysis purposes, and graduates participated in an online survey.ResultsFive structured Masters programmes requiring health science professionals to complete modules and research projects were assessed. Demand for programmes was high. Graduates enjoyed the variety of modules, preferred blended teaching, and regarded assessments as fair. Graduates felt that career paths were not obvious after graduating. Despite this, some have gone on to promote and teach evidence-based health care, and conduct and disseminate research. Areas of concern raised by faculty were quality assurance; research project initiation, implementation and supervisory capacity; staff availability; funding to support implementation and lack of experiential learning.ConclusionAlthough faced with challenges, these programmes build capacity of health professionals to practice in an evidence-informed way, and conduct rigorous research, which are central to advancing the practice of Clinical Epidemiology in Africa.

Global toxocariasis research trends from 1932 to 2015: a bibliometric analysis

BackgroundToxocariasis is a highly prevalent parasitic disease in the tropical regions of the world, with its impact on public health being typically underestimated. To better recognise the trends and characteristics of toxocariasis research, this study is a bibliometric analysis of the global toxocariasis research.MethodsSearches were completed on April 5, 2016, using the Scopus database. A search without any language restriction was performed to extract publications dealing with toxocariasis. Terms related to toxocariasis were used to perform a title keyword search.ResultsA total of 2765 publications comprising 11 document types and published between 1932 and 2015 were included in the analysis. Articles were the most popular document form, accounting for 83.62% of all publications, followed by letters (3.80%) and reviews (3.4%). The annual number of research publications increased from 30 in 1980 to 111 in 2015, indicating that the number of publications on toxocariasis has increased slowly over the past 35 years. The United States of America and Japan are the predominant countries of origin, with 303 articles and 207 articles, respectively, followed by Brazil and the United Kingdom, with 180 (6.5%) each. The h-index for all the publications was 60. The highest h-index were for publications from the United Kingdom (h-index value = 43) and the United States (h-index value = 39); these two countries were also involved with the highest number of international collaborations, with 27 and 28 countries, respectively.ConclusionsDeveloped countries, including the United States, Japan, the United Kingdom, France, Germany and Italy, are the world’s leaders in toxocariasis research, contributing to more than 34% of the total published literature. In addition, developing countries, such as Brazil, Poland, Argentina and India, showed a noticeable increase in published papers on toxocariasis research in recent years. A push for more collaboration is needed to achieve a superior research strategy related to toxocariasis at the global level from the viewpoint of epidemiological data, clinical aspects, medical ecology, molecular aspects and treatment practices associated with toxocariasis.

Fibrinogen and Fibrin in Hemostasis and Thrombosis.

Despite its recognition as a key component of blood clots, the roles of fibrinogen and fibrin (collectively fibrin[ogen]) in hemostasis and thrombosis are insufficiently understood. Consequently, fibrin(ogen) remains an active focus of investigation at all levels of the research spectrum, including fundamental basic/discovery science, epidemiology, and clinical practice and applications. This article briefly reviews basic biology and biochemistry of fibrinogen and fibrin formation, structure, and stability and highlights recent studies published in Arteriosclerosis, Thrombosis, and Vascular Biology and elsewhere. These have enhanced our understanding of fibrin(ogen) and revealed new potential applications for fibrin detection in thrombosis. The fibrinogen molecule is a 340-kDa homodimeric glycoprotein consisting of 2Aα, 2Bβ, and 2γ polypeptide chains linked by 29 disulfide bridges. Fibrinogen synthesis occurs primarily in hepatocytes (Figure 1). Assembly of the 6 chains takes place in a stepwise manner in which single chains assemble first into Aα-γ and Bβ-γ complexes, then into Aα/Bβ/γ half-molecules, and finally into hexameric complexes (Aα/Bβ/γ)2.1 All 6 fibrinogen chains are assembled with their N termini located in a central E nodule and extend outward in a coiled-coil arrangement. The Bβ and γ chains terminate in globular regions known as βC and γC modules, respectively. These regions collectively comprise the so-called D nodule. The Aα chains are the longest; at the end of the coiled-coil region, each chain extends into a highly flexible series of repeats followed by a globular αC region. Using high-resolution atomic force microscopy, Protopopova et al2 obtained striking images of fibrinogen that visualize each of these structural components. Figure 1. Fibrinogen synthesis and expression. Fibrinogen synthesis is regulated by both transcriptional and translational mechanisms. After individual fibrinogen chains are translated, fibrinogen assembly occurs stepwise. Single chains assemble first into Aα-γ and Bβ-γ precursors, then into Aα/Bβ/γ half-molecules, and finally into hexameric complexes (Aα/Bβ/γ) …