Fictive Case Research Articles

Healthcare professionals' competencies and confidence in managing hospitalized patients with type 2 diabetes.

In hospitals, 15%-20% of patients have diabetes. Therefore, all healthcare professionals (HCPs) must have a basic knowledge of in-hospital diabetes management. This survey assessed the knowledge of diabetes among HCPs in Denmark. A 27-item questionnaire was developed and reviewed independently before the survey was distributed. The questionnaire contained seven baseline questions on the HCPs' current workplace, educational level, usual shift routines and years of experience, 18 multiple-choice questions and 2 cases. A total of 252 completed questionnaires were returned by 133 (52.8%) physicians, 101 (40.1%) nurses and 18 (7.1%) healthcare assistants. HCPs answered 50% of the questions correctly. Having experience from endocrinological departments increased the correct response score (0%-100%) by 6.2% points (95% CI 0.3-12.1) (p = 0.039) and 3.1% points (95% CI 1.5-4.7) for every increase in confidence level on a scale from 1 to 10 (p < 0.001). HCPs scored 8 out of 10 on a confidence level scale on average. In a fictive case, 50% of HCPs administered the correct bolus insulin dose. Hyperglycaemia (>10.0 mmol/L) and hypoglycaemia (<3.9 mmol/L) were correctly identified by around 40% of HCPs. Hypoglycaemia was rated more important than hyperglycaemia by most HCPs. Significant gaps in identifying hypo- and hyperglycaemia and correct administration of bolus insulin have been identified, which could be targeted in future education for HCPs. HCPs answered 50% of questions related to in-hospital diabetes management correctly. Experience from endocrinological departments and self-rated confidence levels are associated with HCPs' in-hospital diabetes competencies.

When Anti-CRT Becomes Anti-Care: Navigating Curricular Controversies Amid Voucher-Induced Changes to a Private Religious School Landscape

As access to private religious education expands through vouchers, public discourse has positioned these schools as politically neutral spaces. Teachers who seek to ethically care for students are thus placed in a predicament. In this article, we present the fictive case study of a middle school teacher in a suburban Catholic school that has accepted vouchers and consequently undergone significant demographic and political shifts. When the teacher makes a curricular decision that responds in caring and critical ways to their students, they face a wave of parental opinions that call their instruction and ethical aims into question.

A template Bayesian network for combining forensic evidence on an item with an uncertain relation to the disputed activities

Most of the forensic evidence evaluations given activity level propositions are centered around an item which is assumed to be linked to an alleged activity. However, the relation between an item of interest and an activity may be contested. This study presents a template Bayesian network (BN) for the evaluation of transfer evidence given activity level propositions considering a dispute about the relation of an item to one or more activities. The template BN includes a set of association propositions that enables the combined evaluation of evidence concerning alleged activities of the suspect and evidence concerning the use of an alleged item in those activities. Since the two types of evidence are often from different forensic disciplines, the BN is especially useful in interdisciplinary casework. Throughout the paper, we use a fictive case example that captures the essence of cases for which the template model can be used. The template BN provides a flexible starting point that can be adapted to specific case situations and supports structured probabilistic reasoning by a forensic scientist.

Depression in older adults. What are the differences in clinical practice?

Management of depression in the elderly is a growing public health issue in France. The objective of this study was to compare practitioners' perception of depression severity (i.e., intensity and suicidal risk) and clinical practice (i.e., clinical assessment and medication choice) in elderly versus younger adult patients with major depression. The method consisted of an online questionnaire completed by general practitioners and psychiatrists. Respondents'answers to a fictive case of a patient with major depression were randomized according to the patient's age, if the patient'age was either 40 or 70 years old. We assessed the perceived intensity of the depression, the perceived suicidal risk, the prescription of biological tests and cerebral imaging, and of antidepressive or other psychotropic medications. 102 completed forms were included. Data indicate that there were no significant differences in terms of perceived depression intensity and suicidal risk according to the patients'age. The prescription of biological tests was systematic in both groups, but a significant difference was observed in terms of prescription of brain imaging (71% of respondents for the 70-year-old patient versus 43% for the 40-year-old patient, p <0.005), use of tetracyclic antidepressant (33% if aged 70years versus 2% if aged 40 years, p <0.001) and other psychotropic non-antidepressant medications (69% if aged 70 years versus 85% if aged 40 years, p<0.05). This study did not show any significant difference in the perception of depression according to age. However, it highlights differences in terms of practical care according to age. These results suggest a partial gap between clinical practice and guidelines for the management of major depression in older adults, reflecting the need to favor the dissemination of guidelines and strengthen research for this population.

How Do Physiotherapists Explain Influencing Factors to Chronic Low Back Pain? A Qualitative Study Using a Fictive Case of Chronic Non-Specific Low Back Pain.

While pain is influenced by multiple factors including psychosocial factors, previous research has shown that physiotherapists still favour a biomedical approach. To evaluate: (1) how physiotherapists explain the patient's chronic non-specific low back pain (LBP); (2) whether physiotherapists use one or multiple influencing factors, and (3) whether these factors are framed in a biopsychosocial or biomedical approach. This exploratory qualitative study uses a vignette depicting chronic non-specific LBP and employs a flexible framework analysis. Physiotherapists were asked to mention contributing factors to the pain based on this vignette. Five themes were predefined ("Beliefs", "Previous experiences", "Emotions", "Patients behaviour", "Contextual factors") and explored. Physiotherapists use very brief explanations when reporting contributing factors to chronic pain (median 13 words). Out of 670 physiotherapists, only 40% mentioned more than two different themes and 2/3rds did not see any link between the patients' misbeliefs and pain. Only a quarter of the participants mentioned the patient's worries about pain and movement, which is considered to be an important influencing factor. The lack of a multifactorial approach and the persistent biomedical beliefs suggest that it remains a challenge for physiotherapists to fully integrate the biopsychosocial framework into their management of chronic LBP.

“It Enables Us to Reflect More on Nutrition”: A Mixed Methods Cross-Sectional Study on Preclinical Digital Training in Nurse Education

Adequate nutrition is a basic human right, yet older adults are at high risk of malnutrition. Nutrition is not a part of most nursing curricula. Limited research has been done on digital case-based learning (CBL) in breakout rooms (digital groups); therefore, the aim was to develop and evaluate a preclinical digital CBL unit (3-h synchronously and with an asynchronously flipped classrooms approach) for prevention and treatment of malnutrition and to explore nursing students’ experiences and learning outcomes. Different scenarios for two fictive cases were created in which malnutrition-related challenges were included (such as terminal care) and embedded on the ThingLink platform. In an explorative mixed methods cross-sectional study design, students (n = 78) completed an online evaluation. The results revealed that students wanted more synchronous interaction with educators and less time alone in breakout rooms due to their peers being unprepared, passive and unfamiliar and not turning on their cameras or logging on too late. The learning outcome from quizzes and word clouds were high, but the added pedagogical value of ThingLink seemed low. This explorative study sheds light on central issues related to the use of technology in nurse education, resistance against student active methods and digital pedagogy.

Professionals’ roles in the hospital discharge of older adults in 3 Nordic cities: a vignette study

Abstract Background The hospital discharge process of older adults in need of both medical and social care post hospitalisation requires extensive care coordination. Cooperation and continuity between involved care providers are essential, however, existing care systems including the Nordic care systems, are poorly designed to provide health and social care to patients with complex health and social care needs which increases the risk of certain groups not receiving optimal care. Aim and methods This study aims to examine and compare what roles, responsibility and actions nurses take in the hospital discharge process of older adults with complex care needs in three Nordic cities: Copenhagen (Denmark), Stockholm (Sweden) and Tampere (Finland). A vignette study consisting of three fictive cases was conducted face-to-face with nurses in Copenhagen (n = 11), Stockholm (n = 16) and Tampere (n = 8). Participants were identified through the researchers’ networks and snowball sampling. The vignettes represent older patients with age-related medical conditions of which one also has cognitive loss and one looks after their partner with dementia. The cases further include differences in the home help received by their children, physical obstacles in their homes and unwillingness of becoming a burden to the system. A thematic approach is used for the data analysis. Results and conclusions Preliminary results suggest that the informants’ roles and engagement in the coordination and collaboration may differ both within and between the systems studied, and that they take responsibility beyond their job roles particularly if the patient has no close relatives. The study is of public health importance as it identifies gaps in how the care is organised in the three welfare states targeted. It also sheds light on the complexities of providing universal care in ageing societies where a growing proportion of older adults have both medical and social care needs. Key messages

Talking, Listening and Emancipation:

This paper adds a phenomenological account to the discussion on what constitutes the favorable prospects of the peer-relation in the context of self-help. By drawing on Heidegger’s lectures on St Paul’s First Thessalonians, and engaging in dialogue with a fictive case, we show that more attention needs to be given to how meaning is enacted, rather than simply adopted, in the peer-relation; that is, away from experiential content towards the process of how experiential knowledge is transferred communicatively. This, we argue, may clarify the underpinnings of the peer-relation and its emancipatory potential. Our findings propose a reconsideration of the role played by communicative activities in self-help. And, whereas storytelling has often been propounded as a way to facilitate agency among self-helpers, also the act of listening should receive more attention. By considering listening as an expression of agency, attention is reversed from self-narration on behalf of the person expected to be helped from it, to participation in another person’s story. The enaction approach to the peer-relation elaborated on in this paper invites the reader to rethink the value of talking and listening in helping relationships.

Conflicts in Physical Education Classes - A Systems Theoretical Analysis of the Teacher’s Perspective

This article presents the results of a systems theoretical analysis of conflicts in physical education classes from the teacher’s perspective. Building on the state of current research, a theoretical model to analyse the development and management of sport related conflicts in the school setting is elaborated. This model is used to examine written assignments collected at university seminars on conflicts in a German sport institute. At these seminars, sport science students submitted 40 detailed descriptions of conflicts in physical education classes, which were either collected through an interview or experienced directly in their role as teachers. The empirical material is analysed using qualitative content analysis. Based on a fictive case that is developed for exemplification purposes, all collected cases are considered against the background of the developed model. It differentiates between trivial, stable, slightly, and highly escalated conflicts and examines suitable management strategies. The study concludes that trivial conflicts are common in physical education classes, that teachers use different strategies to manage them, and that this issue is dealt with differently at the organisational level. This preliminary model can be improved through further empirical research that compares different school forms and levels of education at the national and international level.

Big data analysis of ASM retention rates and expert ASM algorithm: A comparative study.

ObjectiveOnly 50% of patients with new‐onset epilepsy achieve seizure freedom with their first antiseizure medication (ASM). A growing body of data illustrates the complexity of predicting ASM response and tolerability, which is influenced by age, sex, and comorbidities. Randomized data with sufficient resolution for personalized medicine are unlikely to emerge. Two potential facilitators of ASM selection are big data using real‐world retention rates or algorithms based on expert opinion. We asked how these methods compare in adult‐onset focal epilepsy.MethodsASM retention rates were determined by cross‐referencing data from comprehensive Swedish registers for 37 643 individuals, with identified comorbidities. Eight fictive cases were created and expert advice was collected from the algorithm Epipick. We compared Epipick suggestions in representative patient subgroups, and determined whether ranking based on retention rate reflected expert advice.ResultsThe Epipick algorithm suggested six ASM alternatives for younger patients and three ASM alternatives for older patients. In the real‐world data, retention rates for the ASMs ranked as best options by Epipick were high; 65%–72% for young patients and 71%–84% for older patients. The lowest retention rate for Epipick suggestions was 42%–56% in younger cases, and 70%–80% in older cases. The ASM with the best retention rate was generally recommended by Epipick.SignificanceWe found a large overlap between expert advice and real‐world retention rates. Notably, Epipick did suggest some ASMs with more modest retention rates. Conversely, clearly inappropriate ASMs (not recommended by Epipick) had high retention rates in some cases, showing that decision systems should not rely indiscriminately on retention rates alone. In future clinical decision support systems, expert opinion and real‐world retention rates could work synergistically.

Community mental health literacy in Tshwane region 1: A quantitative study.

BackgroundAlthough mental health literacy is a major determining factor of mental health outcomes and functional capacity of individuals, there is dearth of research on the issue in South Africa.AimTo assess the literacy of three mental disorders, namely major depressive disorder (MDD), schizophrenia and generalised anxiety disorder (GAD) and to compare the resultant assumed literacy level between urban and townships participants.SettingFive clinics of region 1 in Tshwane, South Africa.MethodA cross-sectional descriptive study was performed between November 2019 and January 2020. A total of 385 questionnaires were distributed equally in all five clinics. By means of questions about three fictive cases with clinical pictures indicative of MDD, schizophrenia and GAD the following were assessed: recognising a mental disorder, identifying the cause and knowledge about what would help best.ResultsThe majority of participants (67.3%) recognised the clinical picture indicative of schizophrenia as a mental disorder, almost half of the participants (49.9%) recognised the clinical picture indicative of MDD as a mental disorder, whilst just more than one third (36.3%) of participants recognised the clinical picture GAD as a mental disorder. Concerning the causes for the clinical pictures, most participants indicated that stress was the cause for MDD and GAD (77.4% and 68.1%, respectively), whilst indicating that biological or psychological (59.5%) causes are relevant to the clinical picture indicative of schizophrenia symptoms. Fewer participants indicated supernatural causes for any of the clinical case (MDD: 2.6%; schizophrenia 15.3%; GAD 4.2%). Most participants chose professional help as the best option for all three cases (MDD 81.3%, schizophrenia 82.2%, GAD 66.1%). The indicators for health literacy in this study show that urban participants had better knowledge than township participants across all questions about the cases.ConclusionOverall, the study indicated a variable knowledge regarding the three mental disorders in region 1 of Tshwane and variable literacy levels in townships compared with urban settings. The results indicate that awareness campaigns should focus on the deficient areas.

A multicentre simulation study of planar whole-body bone scintigraphy in Sweden

BackgroundWhole-body bone scintigraphy is a clinically useful non-invasive and highly sensitive imaging method enabling detection of metabolic changes at an early stage of disease, often earlier than with conventional radiologic procedures. Bone scintigraphy is one of the most common nuclear medicine methods used worldwide. Therefore, it is important that the examination is implemented and performed in an optimal manner giving the patient added value in the subsequent care process. The aim of this national multicentre survey was to investigate Swedish nuclear medicine departments compliance with European practice guidelines for bone scintigraphy. In addition, the effect of image acquisition parameters on the ability to detect metabolic lesions was investigated.MethodsTwenty-five hospital sites participated in the study. The SIMIND Monte Carlo (MC) simulation and the XCAT phantom were used to simulate ten fictive patient cases with increased metabolic activity distributed at ten different locations in the skeleton. The intensity of the metabolic activity was set into six different levels. Individual simulations were performed for each site, corresponding to their specific camera system and acquisition parameters. Simulated image data sets were then sent to each site and were visually evaluated in terms of if there was one or several locations with increased metabolic activity relative to normal activity.ResultThere is a high compliance in Sweden with the EANM guidelines regarding image acquisition parameters for whole-body bone scintigraphy. However, up to 40% of the participating sites acquire lower count density in the images than recommended. Despite this, the image quality was adequate to maintain a stable detection level. None of the hospital sites or individual responders deviated according to the statistical analysis. There is a need for at least 2.5 times metabolic activity compared to normal for a lesion to be detected.ConclusionThe imaging process is well harmonized throughout the country and there is a high compliance with the EANM guidelines. There is a need for at least 2.5 times the normal metabolic activity for a lesion to be detected as abnormal.

Designing Pareto optimal electricity retail rates when utility customers are prosumers

Electric retail rate design is relevant to utilities, customers, and regulators as retail rates impact the utility's revenue as well as the customers' electricity bills. In California, regulators approve rate proposals by privately owned vertical integrated utilities. Approval, however, is subject to compliance with multiple, potentially conflicting objectives such as economic or environmental objectives. Additionally, retail rates are price signals that affect how customers use electricity services. When utility customers change their usage, they also impact the ratemaking objectives to which rates have been designed. This suggests a feedback loop, which is particularly pronounced with prosumers, as they can systematically optimize their interactions with the electricity system. Prevalent ratemaking methods may not deliver retail rates that are optimal for multiple objectives when customers are prosumers. We propose a novel ratemaking method that formalizes the problem of designing retail rates as a multi-criteria optimization problem and accounts for prosumer reactions through a simulation-based optimization approach. Through a fictive case study, we found that the resulting Pareto frontiers are useful in recognizing and balancing tradeoffs among conflicting ratemaking objectives. Additionally, our results indicate that prevailing retail rates in California are not Pareto optimal.

A clinical decision support system improves antibiotic therapy for upper urinary tract infection in a randomized single-blinded study

BackgroundDue to increasing bacterial resistance rates choosing a correct empiric antibiotic therapy is getting more and more complex. Often medical doctors use information tools to make the right treatment choice.MethodsOne hundred sixty six participants (77 medical doctors and 89 medical students) were asked to provide a diagnosis and antibiotic therapy in a simple fictive paper case of upper urinary tract infection (UTI) in a randomized single-blinded study. Participants were randomized to one of four information tools they were allowed to use in the study or control: 1. free internet access, 2. pharmaceutical pocket guide, 3. pocket guide antibiotic therapy, 4. clinical decision support system (CDSS), and control (no information tool). The CDSS was designed for the study. The adherence to the national German UTI guideline was evaluated.ResultsOnly 27.1% (n = 45/166) provided a correct diagnosis of upper UTI and 19.4% (n = 32/166) an antibiotic treatment recommended by national German treatment guidelines indicating their need for information tools. This result was not significantly different between medical doctors and medical students, residents and medical specialists or level of working experience. Using CDSS improved results significantly compared to conventional tools (diagnosis 57.1%; treatment recommendation 40.5%; p < 0,01). Processing time was not different between the use of CDSS and conventional information tools. CDSS users based their decision making on their assigned information tool more than users of conventional tools (73.8% vs. 48.0%; p < 0.01). Using CDSS improved the confidence of participants in their recommendation significantly compared to conventional tools (p < 0.01).ConclusionsOur study suggests that medical professionals require information tools in diagnosing and treating a simple case of upper UTI correctly. CDSS appears to be superior to conventional tools as an information source.

Archéologues et Autochtones : quelle réconciliation possible quand l’éthique et la perspective des uns et des autres divergent?

La décolonisation de la science et la réconciliation avec les communautés autochtones mènent les archéologues vers de nouvelles pratiques archéologiques plus collaboratives et respectueuses des enjeux, des considérations et des perspectives autochtones concernées. Malgré les conséquences généralement positives émanant de ce type de projet, des tensions peuvent surgir entre les différentes parties prenantes lorsque leurs besoins et objectifs ne concordent pas. L’étude de cas fictive présentée ici illustre la complexité de telles situations et les dilemmes éthiques qui peuvent en découler.

Accessing and sharing health information for post-discharge stroke care through a national health information exchange platform - a case study

BackgroundPatients and citizens need access to their health information to get a retrospective as well as a prospective view on their care and rehabilitation processes. However, patients’ health information is stored in several health information systems and interoperability problems often hamper accessibility. In Sweden a national health information exchange (HIE) platform has been developed that enables information exchange between different health information systems. The aim of this study is to explore the opportunities and limitations of accessing and interacting with important health information through the Swedish national HIE platform.MethodsA single case study approach was used for this study as an in-depth understanding of the subject was needed. A fictive patient case with a pseudo-name was created based on an interview with a stroke coordinator in Stockholm County. Information access through the national health information exchange platform and available service contracts and application programming interfaces were studied using different scenarios.ResultsBased on the scenarios created in this study, patients would be able to access some health related information from their electronic health records using the national health information exchange platform. However, there is necessary information which is not retrievable as it is either stored in electronic health records and eHealth services which are not connected to the national health information exchange platform or there is no service contract developed for these types of information. In addition, patients are not able to share information with healthcare professionals.ConclusionThe national Swedish HIE platform provides the building blocks needed to allow patients online access to their health information in a fragmented and distributed health system. However, more complex interaction scenarios allowing patients to communicate with their health care providers or to update their health related information are not yet supported. Therefore it is of great importance to involve patients throughout the design and evaluation of eHealth services on both national and local levels to ensure that their needs for interoperability and information exchange are met.

Effect of Living Wills on End-of-Life Care: A Systematic Review.

To comprehensively assess the effect of a living will on end-of-life care. Systematic review with narrative analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. All interventional and observational studies were included, excepting those with fictive cases. Included studies were conducted in adults with and without living wills, excluding individuals with specific psychiatric living wills. Two authors independently extracted study and participant characteristics and outcomes related to end-of-life care (place of death, hospitalization and intensive care unit management, life-sustaining treatments, restricted care). Risk of bias was assessed using the Risk Of Bias In Non-randomized Studies of Interventions tool. From 7,596 records identified, 28 observational studies were included, 19 conducted in the United States, 7 in Europe, and 1 each in Canada and Australia. Place of death was assessed in 14 studies, life-sustaining treatments in 13, decision for restricted care in 12, and hospitalization in 8. Risk of bias was serious for 26 studies and moderate for 2. Twenty-one studies reported significantly less medical management for individuals with a living will, 3 reported more medical management, and the difference was not significant in 37. Methodological quality of included studies was insufficient to offer reliable results. The effect of living wills appears limited in view of the importance and direction of potential biases. Further studies including larger populations, considering main confounding factors, and documenting the real presence of a living will in medical records are necessary to reach stronger conclusions on the effect of living wills on end-of-life care. J Am Geriatr Soc 67:164-171, 2019.

Evaluation of three machine learning models for self-referral decision support on low back pain in primary care

BackgroundMost people experience low back pain (LBP) at least once in their life and for some patients this evolves into a chronic condition. One way to prevent acute LBP from transiting into chronic LBP, is to ensure that patients receive the right interventions at the right moment. We started research in the design of a clinical decision support system (CDSS) to support patients with LBP in their self-referral to primary care. For this, we explored the possibilities of using supervised machine learning. We compared the performances of the three classification models − i.e. 1. decision tree, 2. random forest, and 3. boosted tree − to get insight in which model performs best and whether it is already acceptable to use this model in real practice. MethodsThe three models were generated by means of supervised machine learning with 70% of a training dataset (1288 cases with 65% GP, 33% physio, 2% self-care cases). The cases in the training dataset were fictive cases on low back pain collected during a vignette study with primary healthcare professionals. We also wanted to know the performance of the models on real-life low back pain cases that were not used to train the models. Therefore we also collected real-life cases on low back pain as test dataset. These cases were collected with the help of patients and healthcare professionals in primary care. For each model, the performance was measured during model validation − with 30% of the training dataset −as well as during model testing − with the test dataset containing real-life cases. The total observed accuracy as well as the kappa, and the sensitivity, specificity, and precision were used as performance measures to compare the models. ResultsFor the training dataset, the total observed accuracies of the decision tree, the random forest and boosted tree model were 70%, 69%, and 72% respectively. For the test dataset, the total observed accuracies were 71%, 53%, and 71% respectively. The boosted tree appeared to be the best for predicting a referral advice with a fair accuracy (Kappa between 0.2 and 0.4). Next to this, the measured evaluation measures show that all models provided a referral advice better than just a random guess. This means that all models learned some implicit knowledge of the provided referral advices in the training dataset. ConclusionsThe study showed promising results on the possibility of using machine learning in the design of our CDSS. The boosted tree model performed best on the classification of low back pain cases, but still has to be improved. Therefore, new cases have to be collected, especially cases that are classified as self-care cases. This to be sure that also the self-care advice can be predicted well by the model.

Freud's Fictions: Fixation, Femininity, Photography

This article takes off from Freud's literary use of the term ‘fixation’ to explore how female sexuality both establishes the universal foundations of Freud's metapsychology and is excluded from it via a reading of one Freud's strangest and most provocative case presentations. Like a primal word, fixation operates in contradictory fashion: it is associated both with regression and futurity, petrified immobility and contingency. Fixation is Freud's name both for the primal origin of sexuality and the very word for what shuts sexuality down. In ‘A Case of Paranoia Running Counter to the Disease’, the first case history devoted to a woman after Dora, Freud recounts his brief encounter with a woman who is brought to Freud because she is suffering from a (presumably) paranoid delusion that her would-be lover has arranged to have her photographed during their sexual engagements. On the basis of his fictionalized account of this fictive case (the woman never actually enters into treatment with him), Freud establishes a curiously suggestive link between fixation, femininity and photography, and introduces, for the first time, the notion of ‘primal phantasies’. By looking how femininity, fixation and photography come together, this article explores how and why Freud attributes quasi-photographic powers to female sexuality as a means of trying to produce a figure for unseen and un-seeable images that come from a primal and unrecoverable past.

The implications of shedder status and background DNA on direct and secondary transfer in an attack scenario

In court questions are often raised related to how trace DNA was deposited, directly during the crime or innocently for instance by secondary transfer. It is therefore of interest to have knowledge of the probability of transfer or secondary transfer in different situations. Factors that could influence transfer probabilities are background DNA and the shedder status of the involved persons. In this study, we have classified participants as high or low DNA shedders. We observed DNA transfer in a simulated attack scenario, and demonstrated that shedder status has a significant influence of transfer rates. We have examined the background DNA in samples from T-shirts worn in an area with frequent human traffic and detected multiple contributors. We further demonstrated that DNA from co-workers of a T-shirt wearer can be secondarily transferred from the environment and detected in samples, and that the composition of background DNA is correlated with the shedder status of the wearer. Finally, we have illustrated the inference with the results of transfer probabilities and a fictive case with the use of a Bayesian network.