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OBJECTIVES: The quality control of serological assays remains controversial. The aim of this project was to describe the problems associated with a working model for controlling these assays and solutions, including using a source of well-defined targets and acceptable limits, a process to identify lot-to-lot reagent variation and an interpretation of the result that accounted for the clinical situation. False-negative results are problematic but can be reduced by identifying and comparing reagent lot variation with previous results. METHODS: The components of the Quality Assurance strategy are the following: Lot-to-lot reagent and calibrator variation assessment; dynamic, big-data approach to determine accurate targets and acceptable limits for manufacturer-provided QC material; negative QC monitoring process; use of commutable EQA with a sufficient method subgroup size to assess bias; clinical assessment of any statistically flagged error; and provision of support to the clinician for the interpretation of results. RESULTS: The model described has been used for twelve months, and acceptable variation has been maintained. CONCLUSIONS: The paper presents a solution that emphasizes the early detection of reagent lot variation and patient risk rather than instrument control. Reducing the risk of a false result to patients requires optimal assay quality control and an effective mechanism to support the clinician's use of these results in diagnosis and monitoring. The problems of serological assays are well-known, but there remain few integrated solutions in the literature.
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INTRODUCTION: In the end of life context, patients are often seen as somewhat passive recipients of care provided by health professionals and relatives, with little opportunity to be perceived as autonomous and active agents. Since studies show a very high prevalence of altruistic dispositions in palliative care patients, we strive to investigate the concept of patient altruism in a set of six interdisciplinary studies by considering three settings: (1) in the general palliative context-by studying to what extent patient altruism is associated with essential psychological outcomes of palliative care (subproject 1a), how altruism is understood by patients (subproject 1b) and how altruism expressed by patients is experienced by palliative care nurses (subproject 1c); (2) in two concrete decision-making contexts-advance care planning (subproject 2a) and assisted suicide (subproject 2b); and (3) through verbal and non-verbal patient communication in palliative care settings (subproject 3). METHODS AND ANALYSIS: Subproject 1a: a cross-sectional study using validated and standardised questionnaires. Subprojects 1b and 1c: a constructivist grounded theory method aiming at developing a novel theory from semistructured interviews in both patients and nurses. Subproject 2a: a thematic analysis based on (1) audio-recordings of advance care planning encounters and (2) follow-up semidirective interviews with patients and their relatives. Subproject 2b: a qualitative study based on thematic analysis of interviews with patients actively pursuing assisted suicide and one of their relatives.Subproject 3: a conversation analysis based on audio and video-recorded interactions in two settings: (1) palliative inpatient unit and (2) advance care planning discussions. ETHICS AND DISSEMINATION: The study project was approved by the Ethics Committees of the Canton of Vaud, Bern and Ticino (no: 2023-00088). In addition to participation in national and international conferences, each project will be the subject of two scientific publications in peer-reviewed journals. Additional publications will be realised according to result triangulation between projects. A symposium opened to professionals, patients and the public will be organised in Switzerland at the end of the project.
Subject(s)
Altruism , Death , Patients , Palliative Care , Cross-Sectional Studies , Patients/psychology , HumansABSTRACT
OBJECTIVES: The concept of altruism is evidenced in various disciplines but remains understudied in end-of-life (EOL) contexts. Patients at the EOL are often seen as passive recipients of care, whereas the altruism of professionals and families receives more research and clinical attention. Our aim was to summarize the state of the scientific literature concerning the concept of patient altruism in EOL contexts. METHODS: In May 2023, we searched 11 databases for scientific literature on patient altruism in EOL contexts in consultation with a health information specialist. The scoping review is reported using the PRISMA checklist for scoping reviews. We used a data charting form to deductively extract data from the selected articles and then mapped data into 4 themes related to our research questions: how authors describe and employ the concept of patient altruism; expressions of patient altruism; consequences of patients' altruistic acts; and possible interventions fostering patient altruism. RESULTS: Excluding duplicates, 2893 articles were retrieved; 33 were included in the final review. Altruism was generally considered as an act or intention oriented toward the benefit of a specific (known) or non-specific (generic) recipient. Patients expressed altruism through care and support, decisions to withhold treatment or actively hasten death, and engagement in advance care planning. Consequences of altruism were categorized in patient-centered (contribution to meaning in life and quality of life), non-patient-centered (leaving a positive impact and saving money), and negative consequences (generating feelings of guilt, exposing individuals with low self-esteem). Interventions to encourage altruism comprised specific interventions, providing opportunities to plan for future care, and recognizing and respecting the patients' altruistic motivations. SIGNIFICANCE OF RESULTS: We identified heterogeneous and limited research conceptualization of patient altruism and its operationalization in palliative care settings. A deeper conceptual, empirical, and theoretical exploration of patient altruism in EOL is necessary.
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BACKGROUND: Empirical studies suggest that gratitude positively influence the quality of life of palliative patients and relatives. However, the literature is marked by a lack of conceptual clarity about what gratitude is and whether it can bring about individual and social benefits. AIM: This paper explores how palliative care patients and relatives understand gratitude, how discursive representations of gratitude may affect their positions, perceptions and relations, and how to conceptualise gratitude in the palliative context. DESIGN: We examine 33 gratitude letters written by patients and relatives and 25 semi-structured interviews conducted as part of a pilot gratitude intervention study. We use a qualitative approach, thematic analysis, within a conceptual framework of discourse analysis. SETTINGS/PARTICIPANTS: Data were collected from 23 patients and 13 relatives recruited through three hospital palliative care services in French-speaking Switzerland. RESULTS: Participants articulate gratitude in five ways: (1) appreciating others; (2) love; (3) need to reciprocate; (4) appreciating the little things; (5) solace amid serious illness. While some of these representations are sources of positive emotions and outlook, wellbeing and hope, others may confirm self-perceptions of powerlessness and burden. These results support a tridimensional conceptualisation of gratitude in palliative care as source of individual benefits, valuing closest relationships and moral obligation. CONCLUSION: Our study suggests that gratitude is a key to a good (end of) life, whilst highlighting potential negative effects. It could help healthcare professionals to better understand what gratitude means to patients and relatives, which may facilitate awareness and fostering of gratitude in palliative care.
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Palliative Care , Quality of Life , Humans , Palliative Care/psychology , Quality of Life/psychology , Qualitative Research , Patients , Health PersonnelABSTRACT
OBJECTIVES: Monitoring quality control for a laboratory or network with multiple instruments measuring the same analyte is challenging. We present a retrospective assessment of a method to detect medically significant out-of-control error conditions across a group of instruments measuring the same analyte. The purpose of the model was to ensure that results from any of several instruments measuring the same analytes in a laboratory or a network of laboratories provide comparable results and reduce patient risk. Limited literature has described how to manage QC in these very common situations. METHODS: Single Levey-Jennings control charts were designed using peer group target mean and control limits for five common clinical chemistry analytes in a network of eight analyzers in two different geographical sites. The QC rules used were 13s/22s/R4s, with the mean being a peer group mean derived from a large population of the same instrument and the same QC batch mean and a group CV. The peer group data used to set the target means and limits were from a quality assurance program supplied by the instrument supplier. Both statistical and clinical assessments of significance were used to evaluate QC failure. Instrument bias was continually monitored. RESULTS: It was demonstrated that the biases of each instrument were not statistically or clinically different compared to the peer group's average over six months from February 2023 until July 2023. Over this period, the error rate determined by the QC model was consistent with statistical expectations for the 13s/22s/R4s rule. There were no external quality assurance failures, and no detected error exceeded the TEa (medical impact). Thus, the combined statistical/clinical assessment reduced unnecessary recalibrations and the need to amend results. CONCLUSIONS: This paper describes the successful implementation of a quality control model for monitoring a network of instruments, measuring the same analytes and using externally provided quality control targets. The model continually assesses individual instrument bias and imprecision while ensuring all instruments in the network meet clinical goals for quality. The focus of this approach is on detecting medically significant out-of-control error conditions.
Subject(s)
Chemistry, Clinical , Laboratories , Humans , Retrospective Studies , Quality Control , BiasABSTRACT
In the semiconducting perovskite materials family, the cesium-lead-chloride compound (CsPbCl3) supports robust excitons characterized by a blue-shifted transition and the largest binding energy, thus presenting a high potential to achieve demanding solid-state room-temperature photonic or quantum devices. Here we study the fundamental emission properties of cubic-shaped colloidal CsPbCl3 nanocrystals (NCs), examining in particular individual NC responses using micro-photoluminescence in order to unveil the exciton fine structure (EFS) features. Within this work, NCs with average dimensions ⟨Lα⟩ ≈ 8 nm (α = x, y, z) are studied with a level of dispersity in their dimensions that allows disentangling the effects of size and shape anisotropy in the analysis. We find that most of the NCs exhibit an optical response under the form of a doublet with crossed polarized peaks and an average inter-bright-state splitting, ΔBB ≈ 1.53 meV, but triplets are also observed though being a minority. The origin of the EFS patterns is discussed in the frame of the electron-hole exchange model by taking into account the dielectric mismatch at the NC interface. The different features (large dispersity in the ΔBB values and occasional occurrence of triplets) are reconciled by incorporating a moderate degree of shape anisotropy, observed in the structural characterization, by preserving the relatively high degree of the NC lattice symmetry. The energy distance between the optically inactive state and the bright manifold, ΔBD, is also extracted from time-resolved photoluminescence measurements (ΔBD ≈ 10.7 meV), in good agreement with our theoretical predictions.
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OBJECTIVES: We aimed to quantify how the vaccine efficacy of BNT162b2, messenger RNA-1273, AD26.COV2-S, and ChAdOx1 nCoV-19 against detected infection by the SARS-CoV-2 Delta and Omicron variants varied by time since the last dose, vaccine scheme, age, and geographic areas. METHODS: We analyzed 3,261,749 community polymerase chain reaction tests conducted by private laboratories in France from December 2021 to March 2022 with a test-negative design comparing vaccinated to unvaccinated individuals. RESULTS: Efficacy against detected infection by Delta was 89% (95% confidence interval, 86-91%) at 2 weeks, down to 59% (56-61%) at 26 weeks and more after the second dose. Efficacy against Omicron was 48% (45-51%) at 2 weeks, down to 4% (2-5%) at 16 weeks after the second dose. A third dose temporarily restored efficacy. Efficacy against Omicron was lower in children and the elderly. Geographical variability in efficacy may reflect variability in the ratio of the number of contacts of vaccinated vs unvaccinated individuals. This ratio ranged from 0 to +50% across departments and correlated with the number of restaurants and bars per inhabitant (beta = 15.0 [0.75-29], P-value = 0.04), places that only vaccinated individuals could access in the study period. CONCLUSION: SARS-CoV-2 vaccines conferred low and transient protection against Omicron infection.
Subject(s)
COVID-19 , Vaccine Efficacy , Child , Aged , Humans , BNT162 Vaccine , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines , ChAdOx1 nCoV-19 , SARS-CoV-2/genetics , France/epidemiologyABSTRACT
BACKGROUND: Psychological research examining the nature and workings of gratitude has burgeoned over the past two decades. However, few studies have considered gratitude in the palliative care context. Based on an exploratory study which found that gratitude was correlated with better quality of life and less psychological distress in palliative patients, we designed and piloted a gratitude intervention where palliative patients and a carer of their choice wrote and shared a gratitude letter with each other. The aims of this study are to establish the feasibility and acceptability of our gratitude intervention and provide a preliminary assessment of its effects. METHODS: This pilot intervention study adopted a mixed-methods, concurrent nested, pre-post evaluation design. To assess the intervention's effects, we employed quantitative questionnaires on quality of life, quality of relationship, psychological distress, and subjective burden, as well as semi-structured interviews. To assess feasibility, we considered patients and carers' eligibility, participation and attrition rates, reasons for refusal to participate, appropriateness of intervention timeframe, modalities of participation, and barriers and facilitators. Acceptability was assessed through post-intervention satisfaction questionnaires. RESULTS: Thirty-nine participants completed the intervention and twenty-nine participated in interviews. We did not find any statistically significant pre/post intervention changes for patients, but found significant decrease in psychological distress for carers in terms of depression (median = 3 at T0, 1.5 at T1, p = .034) and total score (median = 13 at T0, 7.5 at T1, p = .041). Thematic analysis of interviews indicates that overall, the intervention had: (1) multiple positive outcomes for over a third of interviewees, in the form of positive emotional, cognitive, and relational effects; (2) single positive outcomes for nearly half of interviewees, who experienced emotional or cognitive effects; (3) no effect on two patients; and (4) negative emotional effects on two patients. Feasibility and acceptability indicators suggest that the intervention was well received by participants, and that it should adopt flexible modalities (e.g. writing or dictating a gratitude message) to ensure that it is feasible and adapted to individual needs and preferences. CONCLUSIONS: Larger scale deployment and evaluation of the gratitude intervention, including a control group, is warranted in order to have a more reliable evaluation of its effectiveness in palliative care.
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Caregivers , Quality of Life , Humans , Caregivers/psychology , Pilot Projects , Quality of Life/psychology , Palliative Care , Surveys and QuestionnairesABSTRACT
OBJECTIVES: While there is a growing body of literature on the wish to die in older patients, there is little research about their will to live. Exploring the subjective will to live (WTL) offers valuable insights into the patients' resources and motivations, which could help improving geriatric palliative care. The aim of this study was to examine, in long-term care facilities (LTCF), residents' definitions of and factors influencing their WTL. METHODS: Twenty residents (mean age 85.8 ± 10.3 years, 70% women) of 3 Swiss LTCFs gave informed consent and participated in semi-structured interviews about their WTL. Interviews were audio-recorded and transcribed verbatim. Thematic analysis was conducted to identify recurrent themes (40% double coded). RESULTS: The majority of residents reported that they had not thought about the WTL. Nevertheless, they had no difficulty in describing it as innate in their lives. They spontaneously mentioned factors that contributed to their WTL, classified into 5 themes: (1) relationships - primarily with family and health professionals, secondarily with other residents; (2) living situation - the LTCF as a necessary place providing care, constant professional presence, and security, yet necessitates inconveniences such as loss of independence; (3) personality factors - positive outlook on life or spirituality; (4) engagement in routines - organized activities and individual daily routines; and (5) health status - primarily related to functional health. SIGNIFICANCE OF RESULTS: Examining WTL provides important insights into elements that are essential to take into account in planning care and promoting well-being in LTCF residents. The themes identified provide important starting points for improving life in LTCFs.
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We introduce Shennong, a Python toolbox and command-line utility for audio speech features extraction. It implements a wide range of well-established state-of-the-art algorithms: spectro-temporal filters such as Mel-Frequency Cepstral Filterbank or Predictive Linear Filters, pre-trained neural networks, pitch estimators, speaker normalization methods, and post-processing algorithms. Shennong is an open source, reliable and extensible framework built on top of the popular Kaldi speech processing library. The Python implementation makes it easy to use by non-technical users and integrates with third-party speech modeling and machine learning tools from the Python ecosystem. This paper describes the Shennong software architecture, its core components, and implemented algorithms. Then, three applications illustrate its use. We first present a benchmark of speech features extraction algorithms available in Shennong on a phone discrimination task. We then analyze the performances of a speaker normalization model as a function of the speech duration used for training. We finally compare pitch estimation algorithms on speech under various noise conditions.
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Ecosystem , Speech , Humans , Algorithms , Software , Neural Networks, ComputerABSTRACT
BACKGROUND: Due to the complexity of the provision of care for people with dementia, pain assessment and management is still considered to be lacking. An optimal way to support frontline staff in providing pain assessment and management for people with dementia living in nursing homes has not yet been identified. The success of supporting interventions seems dependent on contextual factors in the nursing homes. This study, therefore, analyzes the feasibility of a nurse-led training intervention, using repeated on-site case studies, in modifying pain intensity and frequency in people with dementia. METHODS: Using a quasi-experimental design, we undertook a multi-center study of nurse-led training in pain management, with subsequent on-site case studies. Healthcare workers from 3 nursing homes assessed pain in 164 residents with dementia over 147 days. We used mixed-effect growth curve models with spline regression to analyze the data. RESULTS: We found that on-site case studies support frontline staff with pain management and assessment. Repeated reflection in case studies led to significantly longer pain free intervals (from 4.7 at baseline to 37.1 days at second follow-up) and decreased frequency of pain events (OR 0.54 at first follow-up and 0.43 at second follow-up). However no trends regarding pain intensity could be found. Therefore, on-site case studies may be valuable for improving pain frequency and pain-free intervals over time. CONCLUSION: This feasibility study shows the potential of on-site support for frontline nursing home staff. On-site case studies may also affect health outcomes in people with dementia. However, the complexity of dementia care necessitates the management of a broader range of needs. TRIAL REGISTRATION: The study was retrospectively registered on the tenth of January 2017 with the German registry of clinical trials (DRKS00009726).
Subject(s)
Dementia , Pain Management , Humans , Dementia/therapy , Dementia/drug therapy , Health Personnel , Nursing Homes , Pain , Quality of LifeABSTRACT
OBJECTIVES: Posttraumatic growth (PTG) refers to positive psychological changes resulting from individuals' inner struggles with traumatic events such as life-threatening illness. Although palliative care patients are confronted with their own mortality, little is known about their PTG experience. This study investigates whether PTG is an empirically relevant concept for palliative patients by assessing the prevalence and areas of growth, and examining associations with psychological distress and quality of life. METHODS: Participants were recruited in Switzerland. Using validated questionnaires, we assessed PTG (Posttraumatic Growth Inventory, PTGI), psychological distress (Hospital Anxiety and Depression Scale), and quality of life (McGill-Quality of Life Questionnaire - Revised). We performed descriptive analyses, Spearman correlations, and linear regressions. RESULTS: Fifty-five patients completed the PTGI, 44% of whom experienced no/low growth, 47% moderate growth, and 9% high/very high growth. Participants experienced the greatest positive changes in terms of appreciating life and relating to others. We found significant negative bivariate correlations between PTG and psychological distress (r = -0.33) and between PTG and depression (r = -0.47). Linear regressions showed that PTG is associated with depression (ß = -0.468; p = 0.000), but not with anxiety or quality of life (adjusted R2 = 0.219). SIGNIFICANCE OF RESULTS: Over half of our patients experienced moderate to very high growth, indicating that PTG is an empirically relevant psychological process in palliative care. PTG is associated with lower levels of depression, possibly as those experiencing growth are more able to process past traumas and build a more positive outlook on one's life and self. By contrast, the relative independence of anxiety and PTG points to the likely coexistence of positive and negative psychological responses to trauma. The lack of association between PTG and quality of life points to the uniqueness of the PTG concept in capturing how people access deeper meaning and greater appreciation of life along the path toward posttraumatic self-reconstruction.
Subject(s)
Posttraumatic Growth, Psychological , Psychological Distress , Stress Disorders, Post-Traumatic , Humans , Adaptation, Psychological , Palliative Care , Quality of Life/psychology , Stress Disorders, Post-Traumatic/psychologyABSTRACT
Palliative care is frequently associated with end of life and cancer, both in the general population and among healthcare professionals. ID-PALL is a new, short, easy-to-use instrument to help professionals to identify general or specialized palliative care needs in adult inpatients in different care settings. ID-PALL has already been validated in internal medicine units. ID-PALL should help professionals to discuss a suitable palliative care project, in order to maintain the best quality of life for patients and their relatives, and to involve palliative care specialists at the appropriate time. Recommendations for clinical practice are also proposed to guide professionals after the identification phase.
Que ce soit dans la population ou chez les professionnels de la santé, les soins palliatifs sont fréquemment associés à la fin de vie et au cancer. ID-PALL est un nouvel instrument court, facile d'utilisation, pour aider les professionnels à identifier les besoins de soins palliatifs généraux ou spécialisés chez les patients adultes hospitalisés dans les différents milieux de soins et déjà validé en médecine interne. ID-PALL devrait aider les professionnels à se mettre en discussion autour d'un projet de soins palliatifs adapté, afin de maintenir la meilleure qualité de vie possible pour les patients et leurs proches et également permettre d'appeler les spécialistes de soins palliatifs au moment opportun. Des recommandations pour la pratique clinique sont également proposées pour orienter les professionnels après la phase d'identification.
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Neoplasms , Palliative Care , Adult , Health Personnel , Humans , Inpatients , Neoplasms/therapy , Quality of LifeABSTRACT
OBJECTIVE: The objective of this review was to provide a comprehensive overview of the measurement properties of the available instruments used by clinicians for identifying adults in need of general or specialized palliative care in hospital settings. INTRODUCTION: Identification of patients in need of palliative care has been recognized as an area where many health care professionals need guidance. Differentiating between patients who require general palliative care and patients with more complex conditions who need specialized palliative care is particularly challenging. INCLUSION CRITERIA: We included development and validation studies that reported on measurement properties (eg, content validity, reliability, or responsiveness) of instruments used by clinicians for identifying adult patients (>18âyears and older) in need of palliative care in hospital settings. METHODS: Studies published until March 2020 were searched in four databases: Embase.com, MEDLINE (Ovid), PubMed, and CINAHL (EBSCO). Unpublished studies were searched in Google Scholar, government websites, hospice websites, the Library Network of Western Switzerland, and WorldCat. The search was not restricted by language; however, only studies published in English or French were eligible for inclusion. The title and abstracts of the studies were screened by two independent reviewers against the inclusion criteria. Full-text studies were reviewed for inclusion by two independent reviewers. The quality of the measurement properties of all included studies were assessed independently by two reviewers according to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodology. RESULTS: Out of the 23 instruments identified, four instruments were included, as reported in six studies: the Center to Advance Palliative Care (CAPC) criteria, the Necesidades Paliativas (NECPAL), the Palliative Care Screening Tool (PCST), and the Supportive and Palliative Care Indicators Tool (SPICT). The overall psychometric quality of all four instruments was insufficient according to the COSMIN criteria, with the main deficit being poor construct description during development. CONCLUSIONS: For the early identification of patients needing palliative care in hospital settings, there is poor quality and incomplete evidence according to the COSMIN criteria for the four available instruments. This review highlights the need for further development of the construct being measured. This may be done by conducting additional studies on these instruments or by developing a new instrument for the identification of patients in need of palliative care that addresses the current gaps in construct and structural validity. SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO CRD42020150074.
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Hospice and Palliative Care Nursing , Palliative Care , Adult , Hospitals , Humans , Psychometrics , Reproducibility of ResultsABSTRACT
In order to reach human performance on complex visual tasks, artificial systems need to incorporate a significant amount of understanding of the world in terms of macroscopic objects, movements, forces, etc. Inspired by work on intuitive physics in infants, we propose an evaluation benchmark which diagnoses how much a given system understands about physics by testing whether it can tell apart well matched videos of possible versus impossible events constructed with a game engine. The test requires systems to compute a physical plausibility score over an entire video. To prevent perceptual biases, the dataset is made of pixel matched quadruplets of videos, enforcing systems to focus on high level temporal dependencies between frames rather than pixel-level details. We then describe two Deep Neural Networks systems aimed at learning intuitive physics in an unsupervised way, using only physically possible videos. The systems are trained with a future semantic mask prediction objective and tested on the possible versus impossible discrimination task. The analysis of their results compared to human data gives novel insights in the potentials and limitations of next frame prediction architectures.
Subject(s)
Algorithms , Benchmarking , Humans , Learning , Neural Networks, Computer , PhysicsABSTRACT
Palliative care is frequently associated with the end of life and cancer. However, other patients may need palliative care, and this need may be present earlier in the disease trajectory. It is therefore essential to identify at the right time patients who need palliative care and to distinguish between those in need of general palliative care and those for whom a referral to specialists is required. ID-PALL has been developed as an instrument to support professionals in this identification and to discuss a suitable palliative care project, in order to maintain the best quality of life for patients and their relatives. Recommendations for clinical practice are also proposed to guide professionals after the identification phase.
Subject(s)
Neoplasms , Palliative Care , Humans , Quality of LifeABSTRACT
We compared PCR results from SARS-CoV-2-positive patients tested in the community in France from 14 June to 30 July 2021. In asymptomatic individuals, Cq values were significantly higher in fully vaccinated than non-fully vaccinated individuals (effect size: 1.7; 95% CI: 1-2.3; pâ¯< 10-6). In symptomatic individuals and controlling for time since symptoms, the difference vanished (pâ¯= 0.26). Infections with the Delta variant had lower Cq values at symptom onset than with Alpha (effect size: -3.32; 95% CI: -4.38 to -2.25; pâ¯< 10-6).
Subject(s)
COVID-19 , Vaccines , France , Humans , SARS-CoV-2 , Viral LoadABSTRACT
BACKGROUND: Discovered in 2019 in the region of Wuhan, China, the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) rapidly established itself as a major pathogenic agent of morbidity and mortality. France has implemented a strategy to fight this virus which relies essentially on widespread RT-PCR virological testing in order to isolate positive patients. Antigenic tests have recently been made available to help the diagnostics. We have conducted a retrospective study to determine the sensitivity of these antigenic tests, comparing them to the reference RT-PCR method. METHOD: Between December 7, 2020 and January 31, 2021, each patient we received in our laboratories for an RT-PCR test was enrolled. Out of 271,649 patients, 4,881 had been submitted to an antigenic test (TDR) in the preceding 24 hours. Comparing the data resulting from both tests, we established the sensitivity and the specificity of the antigenic tests. For our analysis we included the parameter of symptom and/or the value of Cycles threshold (Ct) in our parameters. RESULTS: The sensitivity of the TDRs compared to all the positive RT-PCR tests is 56%. We further demonstrate the correlation between the symptom duration and the reduction of the nasopharyngeal viral load. Based on this data, we have established that the sensitivity of the TDRs decreases very rapidly after symptom onset, contrary to the estimated viral load in the RT-PCR. Indeed, less the 24 hours after clinical symptom onset, the sensitivity of the TDRs decreases from 74% to 60%. By including the Ct value in our parameters, we have established that, despite a high viral load and clinical symptoms since 7 days or less, the sensitivity of the TDRs is 66%. Although, a high number of asymptomatic patients among carriers of SARS-CoV-2, we have estimated a specificity of 93% for our test. CONCLUSIONS: Performance in terms of sensitivity and specificity of the TDR, as assessed in practice, are inferior to those given by the manufacturer, which raises several questions. What is the impact of falsely negative results for patients carrying a high viral load? Are the implemented measures sufficient to prevent the epidemic?