Dichotomous Test Research Articles

Acute exercise performed during the late consolidation phase improves memory persistence by hippocampal protein synthesis and catecholamine modulation

Memory persistence is a crucial aspect of long-term memory (LTM) and involves late consolidation processes that modulate memory stability over time. Acute physical exercise (PE) has emerged as a potential strategy to modulate memory consolidation and enhance memory persistence. While its effects have been extensively explored in the early consolidation phase, its impact on the late phase remains unexplored. In this study, we investigated the effects and mechanisms of an acute PE on the late consolidation window of novel object recognition (NOR) memory in rats. A 30-minute running session applied 11 h after NOR memory acquisition significantly increased memory persistence for at least 7 days. The inhibition of hippocampal protein synthesis immediately after acute PE using anisomycin (a ribosomal inhibitor) or rapamycin (an mTOR pathway inhibitor) impaired the effect of PE on memory persistence. Animals only presented memory 1 day after acquisition. The same effect was observed with the inhibition of beta-adrenergic receptors by timolol. Although there were no differences between the groups' comparison, blocking D1/D5 receptors after acute PE resulted in a lack of memory persistence in the dichotomous testing (remember/non-remember). Therefore, our exploration of the mechanisms underlying this enhancement revealed the involvement of protein synthesis and the requirement of beta-adrenergic and dopaminergic D1/D5 receptors in the dorsal hippocampus. These findings provide valuable insights into PE as a potential memory modulator, contributing to expanding our understanding of memory consolidation dynamics and acute PE effects.

Salinity limits mosquitofish invasiveness by altering female activity during mate choice

Biological invasions of freshwater habitats are of increasing biological and economical concern, and both, salinity and parasites are considered to be key contributors to invasion success. Salinity, for example, influences the distribution of invasive mosquitofish (Gambusia holbrooki) and native killifish (Aphanius fasciatus) in Europe, with the latter now predominantly confined to high-salinity habitats. Here, we examined how salinity might affect female activity and preference for large and non-parasitized males in multiple populations of mosquitofish and killifish in Sardinia, Italy. We predicted that (1) females of both species would associate preferentially with larger and uninfected males, and that (2) female behavior in both species would be significantly influenced by salinity. We used dichotomous choice tests, in which we presented focal females with video animations of photos of the same male but differing in body size and presence/absence of an ectoparasite (Lernaea cyprinacea). We calculated female preference based on association time and quantified female inactivity as time spent in the central neutral zone during trials. Contrary to prediction 1, females did not prefer the large or uninfected male stimuli over their counterparts in any of the populations. However, while salinity did not significantly affect female preferences, it did significantly affect their activity, with mosquitofish becoming more inactive at higher salinities and killifish exhibiting the opposite pattern, matching prediction 2. These results suggest that salinity limits mosquitofish invasiveness by reducing their activity and thus provides a refuge for the Mediterranean killifish.

Improving Cancer Probability Estimation in Nondiagnostic Bronchoscopies: A Meta-analysis

BackgroundIn patients with peripheral pulmonary lesions (PPL), non-diagnostic bronchoscopy, results are not uncommon. The conventional approach to estimate the probability of cancer (pCA) following bronchoscopies relies on dichotomous test assumptions, utilizing prevalence, sensitivity, and specificity to determine negative predictive value (NPV). However, bronchoscopy is a multi-disease test, raising concerns about the accuracy of dichotomous methodologies. Research QuestionBy how much does calculating pCA using a dichotomous approach (pCAdichotomous) underestimate the true pCA when applied to multi-disease tests like bronchoscopy for the diagnosis of PPL? MethodsMeta-analysis of cohort studies involving radial-EBUS for PPL. PRISMA guidelines were followed, constructing 2×2 contingency tables for calculating pCAdichotomous. For the multi-disease test approach, 3×3 contingency tables for calculating pCAmulti-disease using the likelihood ratio method for non-diagnostic results LR(T0) was used. Observed malignancy rates in patients with non-diagnostic results were compared to pCAdichotomous and pCAmulti-disease. ResultsIn 46 studies (7506 patients), malignancy was the underlying diagnosis in 76%, another specific disease in 13%, and non-specific fibrosis/scar in 10%. The percentage of patients with non-diagnostic results who had malignancy matched pCAmulti-disease across all studies. In contrast, pCAdichotomous consistently underestimated cancer risk (median difference: 0.12, 25th−75th percentile: 0.06−0.23), particularly in studies with a higher prevalence of non-malignant disease. The pooled LR(T0) was 0.46 (95% CI 0.40−0.52, I2 76%, p<0.001), and correlated with the prevalence of non-malignant diseases (p=0.001). InterpretationConventional dichotomous methods for estimating pCA after non-diagnostic bronchoscopies underestimate the likelihood of malignancy. Physicians should opt for the multi-disease test approach when interpreting bronchoscopy results.

Results of Quantitative and Qualitative Assessment of Color Vision in Patients with Congenital Partial Atrophy of the Optic Nerve

Background. Congenital partial atrophy of the optic nerve is one of the main causes of blindness and low vision in patients with fundus pathology, and the study of color vision is important in diagnosis and monitoring visual functions in patients with this disease.Purpose: to study the possibilities of using the own developed method of quantitative and qualitative assessment of color vision in patients with partial optic nerve atrophy.Materials and methods. 55 patients aged from 8 to 20 years with congenital partial atrophy of the optic nerve (PAON) with a typical fundus pattern and EFI indicators for this disease were observed. The control group included 116 people of the same age without fundus pathology and with normal visual acuity. To study color vision in both groups, the classic FarnsworthMunsell Dichotomous D15 Test and the own developed method for quantitative and qualitative assessment of color vision were used.Results. The method developed by us made it possible to identify color perception disorders of varying severity in the majority (about 90 %) of patients with PAON. In the control group, no color perception disorders were detected in more than 70 % of the subjects. Quantitative assessment of color vision conducted using the method developed by us demonstrates significantly higher indicators of the total error of perception of color tones in patients with PAON (35.6 ± 3.2 degrees for a better-seeing eye and 39.9 ± 3.3 degrees for a worse-seeing eye) in comparison with the subjects of the control group (6.2 ± 1.1 degrees for a better-seeing eye and 7.5 ± 1.3 degrees for a worse-seeing eye). The severity of color perception disorders in patients with PAON does not depend on age, but has a significant inverse relationship with visual acuity. In the group of patients with PAON, when examining both better-seeing eye and worse-seeing eye, perception disorders of all color tones are detected with a slight predominance of disorders of perception of red, green and blue. The method developed by us has sufficiently higher sensitivity and specificity in comparison with the classic Farnsworth-Mansell D-15 test.Conclusion. The method developed by us makes it possible to effectively carry out a quantitative and qualitative assessment of the state of color perception in patients with PAON.

No geographical differences in male mate choice in a widespread fish, Limia perugiae.

Behavior, like most other traits, can have a spatial component, and variability of behavior at the population level is predicted. In this article, we explore male mate choice at this level. Male mate choice, while maybe not as common as female choice, is expected to evolve when males respond to significant variation in female quality and, for example, prefer females with higher fecundity. In fishes, higher fecundity is associated with larger body size, an easily measured trait. In this study, we investigated the presence of male mate choice for larger females in a widespread species of livebearing fish, Limia perugiae, while comparing preferences between populations. We hypothesized that environmental variation, for example, in the form of salinity, might result in population differences. Using dichotomous choice tests, we analyzed behavioral data for 80 individuals from 7 distinct populations from Hispaniola. We found that L. perugiae males significantly preferred large females, but there was no significant statistical variation between populations.

Social opportunities and mate preference improve breeding success in Caribbean iguanas

Conservation breeding of West Indian rock iguanas (Cyclura) has met with limited success historically. Many facilities witness high levels of aggression and mate incompatibility resulting in failed breeding introductions which often require animals to be separated. This may be due, in part, to lack of knowledge of how mate familiarity and preference affect reproductive outcomes in these species. We investigated whether social exposure during the pre-breeding season influenced copulation success, egg production, and breeding behaviors. Additionally, we examined whether mate preference, as determined by pre-mating dichotomous choice tests, increased these reproductive outcomes. Female rock iguanas that were socialized with males prior to breeding opportunities copulated with familiar males for longer periods of time than females that were not socialized. Socialization opportunities did not alter male reproductive success measurements or breeding behavior. Female rock iguanas introduced for mating to their preferred partners had a higher probability of successful copulations, higher average number of copulations, and less resting behavior during introductions than females mated to non-preferred males. Male mate preference had no effect on reproductive success measurements during mating introductions. These results indicate that socializing animals and providing mate choice opportunities increase breeding success of rock iguanas under managed care.

Competitiveness of Fruits' and Vegetables' Exports from India

"The study aims to evaluate the competitiveness of selected fruits and vegetables in India by using four revealed comparative advantage (RCA) indices from 2001 to 2019 based on International Trade Centre (INTRACEN) database. The results revealed that out of 25 selected fruits and vegetable products, only seven product groups namely onion fresh, cucumber &amp; gherkin, dried vegetables, cooked or uncooked vegetables, cashewnut shelled, guava &amp; mango and tamarind showed comparative advantage in all the RCA indices. While other fruits and vegetables exhibited comparative disadvantage in a few RCA indices. To measure the consistency across different measures of RCAs, the study used three consistency tests, namely, cardinal, ordinal, and dichotomous tests. The findings indicate that the four indices exhibit greater consistency when measured as an ordinal scale, while showing less consistency when measured as cardinal or dichotomous scales. Moreover, stability of these indices was also revealed in the analysis. The study also suggested specific strategies to boost fruits and vegetables products’ exports."

Observational cohort study to validate SEARCH, a novel hierarchical algorithm to define long-term outcomes after pulmonary embolism

BackgroundChronic dyspnoea and exercise impairment are common after acute pulmonary embolism (PE) but are not defined and quantified sufficiently to serve as outcomes in clinical trials. The planned project will...

Reporting Standards for Diagnostic Testing: Guidance for Authors From Editors of Respiratory, Sleep, and Critical Care Journals.

Diagnostic testing is fundamental to medicine. However, studies of diagnostic testing in respiratory medicine vary significantly in terms of their methodology, definitions, and reporting of results. This has led to often conflicting or ambiguous results. To address this issue, a group of 20 respiratory journal editors worked to develop reporting standards for studies of diagnostic testing based on a rigorous methodology to guide authors, peer reviewers, and researchers when conducting studies of diagnostic testing in respiratory medicine. Four key areas are covered, including defining the reference standard of truth, measures of dichotomous test performance when used for dichotomous outcomes, measures of multichotomous test performance for dichotomous outcomes, and what constitutes a useful definition of diagnostic yield. The importance of using contingency tables for reporting results is addressed with examples from the literature. A practical checklist is provided as well for reporting studies of diagnostic testing.

P-435 HPV and infertility in couples requiring Assisted Reproduction Techniques (ART).

Abstract Study question How frequent is Human Papilloma Virus (HPV) infection in both partners of infertile couples referring to our ART center and whats its impact? Summary answer Only 6% of infertile couples are positive for HPV and infection has no impact on embryologic parameters. What is known already There is limited and conflicting evidence about the relationship between HPV infection in male partners and infertility. Notably, most of the previous studies did not assess the presence of the infection in both partners in the context of ART. Furthermore, even if considered, the influence of the infection of the female partner may be underestimated because only data on adverse pregnancy outcomes were evaluated. Elucidating the HPV-positive status of the two individuals belonging to the couple could open up new scenarios. Study design, size, duration This prospective cohort study was performed on 81 couples. The analysis was conducted on semen samples of male patients and on cervical samples of female partners who underwent assisted reproduction techniques (ART) treatment at the infertility unit of Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico of Milan from February 2022 to November 2022. Participants/materials, setting, methods The female partecipants were recruited before the beginning of the controlled ovarian stimulation (COS) while male participants were recruited on the day of the female ovum pick-up (OPU). The technique used to assess the presence of the HPV virus was the Real Time PCR (RT-PCR). Personal characteristics, lifestyle habits and sexual habits were investigated as possible favoring elements for the insurgence of HPV infection. Main results and the role of chance Among 81 couples recruited, 12 men and 22 women tested positive for high- and low risk HPV viruses. This streins corrisponds to a prevalence of about 15% (95% CI: 9-24%) for males and 27% (95% CI: 19-38%) for females. Among these positive couples, only 5 cases (6%, 95% CI: 3-14%) simultaneously tested positive for both partners: in two pairs they were positive for the same viral strains, in two other pairs there was no concordance between the viral strains found, and in one pair there was only a partial concordance. McNemar's test (a dichotomous evaluation test for data paired aimed at assessing possible associations) was not significant. No differences in embryo developmental failure, “top-quality” embryo formation and “top-quality” blastocyst formation were found between the two groups (positive vs negative couples). Limitations, reasons for caution A possible limitation of the study is the small sample size. Additionally we mainly focused on the impact of infection by HPV on embryological variables, without considering developmental pregnancies and live birth rate. Wider implications of the findings The very low concordance observed suggests that infection follows intricate pathways, far beyond the trivial view of a ping-pong effect between partners of the couple. These results suggest that HPV infection probably develops independently in the two individuals of the couple, as if there is not a mutual influence. Trial registration number NOT APPLICABLE

G8 screening and health-care use in patients with cancer

G8 screening and health-care use in patients with cancer

Accuracy of aMMP-8 point-of-care test in indicating periodontal treatment outcomes in stage III/IV periodontitis: A24-week follow-up study.

To analyse the correspondence between aMMP-8 PoC test results and the clinical endpoints of non-surgical periodontal treatment in stage III/IV periodontitis. The diagnostic success of the active-matrix metalloproteinase-8 (aMMP-8) point-of-care (PoC) test has been demonstrated in various studies, but the evidence of its accuracy following periodontal treatment is limited. Altogether 42 stage III/IV grade C periodontitis patients were included in this prospective diagnostic study. Clinical periodontal indices were recorded, aMMP-8 PoC test was applied and mouthrinse was collected before and at 6, 12 and 24 weeks after non-surgical periodontal treatment. Quantitative aMMP-8 levels were determined with immunofluorometric assay (IFMA) for the verification of the PoC test results. The accuracy of the aMMP-8 PoC test was assessed using previously established clinical endpoints as references. Sensitivity and specificity of aMMP-8 PoC test to indicate clinical endpoints were ranged as follows: Sensitivity 71.4% at baseline, 39.3%-42.4% at week 6, 28.6%-32.4% at week 12 and 35.3%-42.9% at week 24; specificity 64.3%-80% at week 6, 40%-57.1% at week 12 and 56%-64.3% at week 24. The accuracy of aMMP-8 PoC test in identifying clinical endpoints after non-surgical periodontal treatment is reduced in relation to baseline. Individual healing patterns of each diseased pocket eventually limit the accuracy of the dichotomous aMMP-8 oral rinse test during the post-treatment period.

Four-Parameter Guessing Model and Related Item Response Models

Guessing effects frequently occur in testing data in educational or psychological applications. Different item response models have been proposed to handle guessing effects in dichotomous test items. However, it has been pointed out in the literature that the often employed three-parameter logistic model poses implausible assumptions regarding the guessing process. The four-parameter guessing model has been proposed as an alternative to circumvent these conceptual issues. In this article, the four-parameter guessing model is compared with alternative item response models for handling guessing effects through a simulation study and an empirical example. It turns out that model selection for item response models should be rather based on the AIC than the BIC. However, the RMSD item fit statistic used with typical cutoff values was found to be ineffective in detecting misspecified item response models. Furthermore, sufficiently large sample sizes are required for sufficiently precise item parameter estimation. Moreover, it is argued that the criterion of the statistical model fit should not be the sole criterion of model choice. The item response model used in operational practice should be valid with respect to the meaning of the ability variable and the underlying model assumptions. In this sense, the four-parameter guessing model could be the model of choice in educational large-scale assessment studies.

La curva ROC

The ROC curve is a statistical tool used to evaluate the discriminative capacity of a dichotomous diagnostic test. These are curves in which sensitivity is presented as a function of false positives (complementary to specificity) for different cut-off points. They are useful for choosing the most appropriate cut-off point for a test, knowing its overall performance and comparing the discriminative capacity of 2 or more diagnostic tests.

Sample size planning for replication studies: The devil is in the design.

Replication is central to scientific progress. Because of widely reported replication failures, replication has received increased attention in psychology, sociology, education, management, and related fields in recent years. Replication studies have generally been assessed dichotomously, designated either a "success" or "failure" based entirely on the outcome of a null hypothesis significance test (i.e., p < .05 or p > .05, respectively). However, alternative definitions of success depend on researchers' goals for the replication. Previous work on alternative definitions for success has focused on the analysis phase of replication. However, the design of the replication is also important, as emphasized with the adage, "an ounce of prevention is better than a pound of cure." One critical component of design often ignored or oversimplified in replication studies is sample size planning, indeed, the details here are crucial. Sample size planning for replication studies should correspond to the method by which success will be evaluated. Researchers have received little guidance, some of which is misguided, on sample size planning for replication goals other than the aforementioned dichotomous null hypothesis significance testing approach. In this article, we describe four different replication goals. Then, we formalize sample size planning methods for each of the four goals. This article aims to provide clarity on the procedures for sample size planning for each goal, with examples and syntax provided to show how each procedure can be used in practice. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Meta-analysis of dichotomous and ordinal tests with an imperfect gold standard.

Standard methods for the meta‐analysis of medical tests, without assuming a gold standard, are limited to dichotomous data. Multivariate probit models are used to analyse correlated dichotomous data, and can be extended to model ordinal data. Within the context of an imperfect gold standard, they have previously been used for the analysis of dichotomous and ordinal test data from a single study, and for the meta‐analysis of dichotomous tests. However, they have not previously been used for the meta‐analysis of ordinal tests. In this article, we developed a Bayesian multivariate probit latent class model for the simultaneous meta‐analysis of ordinal and dichotomous tests without assuming a gold standard, which also allows one to obtain summary estimates of joint test accuracy. We fitted the models using the software Stan, which uses a state‐of‐the‐art Hamiltonian Monte Carlo algorithm, and we applied the models to a dataset in which studies evaluated the accuracy of tests, and test combinations, for deep vein thrombosis. We demonstrate the issues with dichotomising ordinal test accuracy data in the presence of an imperfect gold standard, before applying and comparing several variations of our proposed model which do not require the data to be dichotomised. The models proposed will allow researchers to more appropriately meta‐analyse ordinal and dichotomous tests without a gold standard, potentially leading to less biased estimates of test accuracy. This may lead to a better understanding of which tests, and test combinations, should be used for any given medical condition.

Understanding the Shades of Gray in Diagnosis-An Online Course in Bayesian Reasoning.

Foundational skills in Bayesian reasoning may aid clinical decision-making, decrease overreliance on single diagnostic tests, and improve patient care. However, clinicians are often unskilled in applying Bayes' rule at the bedside, such as using likelihood ratios to calculate posttest probabilities.1While published literature measures clinicians' abilities to update conditional probabilities based on dichotomous test results, many diagnostic tests used in clinical practice are not dichotomous.1 One of the gaps in clinical decision-making revolves around the interpretation of continuous tests such as D-dimer, troponin, and procalcitonin. Although often dichotomized as “normal” and “abnormal” for simplicity, the test's degree of abnormality may have a profound effect on how the result changes the disease probability. Explicit instruction in understanding the “shades of gray” in diagnostic test interpretation is lacking.Clinicians who are deficient in knowledge of Bayesian reasoning are often involved in trainee education. Faculty development initiatives to improve Bayesian reasoning would presumably have positive downstream effects on learners. Educational efforts may be limited by faculty time, availability, and lack of local experts in Bayesian reasoning. Furthermore, the recent COVID-19 pandemic has presented additional challenges to designing and delivering in-person educational curricula.We developed an online, self-paced, asynchronous, case-based curriculum in Bayesian reasoning. The course uses a flipped classroom approach and revolves around 10 core clinical cases. Each case represents a realistic patient scenario. The learner reads each scenario and answers a series of questions assessing a range of skills involved in Bayesian reasoning. The learner is asked to incorporate various findings in the estimation of disease probability, updating disease probability based on new information and integrating this information to guide subsequent management decisions. Each case is followed by video explanations that guide learners through the fundamentals of Bayesian reasoning. The course gradually builds from simple test characteristics, such as sensitivity and specificity, to understanding multilevel likelihood ratios, receiver operating characteristic curves, and action thresholds when making decisions under uncertainty. Course completion is estimated to take 6 to 8 hours. All course materials were created by the study authors.The course was piloted to faculty volunteers beginning June 2021 for the Division of Hospital Medicine faculty at the University of Colorado. Informed consent was obtained. Each participant took 15-question pre- and posttests to evaluate the baseline and gained knowledge. Participants also self-assessed their prior knowledge, ranked the importance of Bayesian reasoning in their clinical care, and noted their satisfaction with the course on a 4-point Likert scale that excluded neutral responses. The Colorado Multiple Institutional Review Board granted the study an exempt status.As of October 2021, 18 out of 20 invited faculty members started the course, and 12 (67%) completed it. Overall, 11 of 12 (92%) faculty members rated their prior knowledge in Bayesian reasoning as “somewhat” or “very weak.” Most (10 of 12) participants rated the importance of Bayesian reasoning in clinical care as “very important,” and the rest rated it as “somewhat important.” All participants (100%) reported feeling “very satisfied” with the course and indicated that it is “very likely” they would recommend the course to a colleague. The pretest assessment demonstrated serious deficiencies in all tested domains, and the posttest assessment showed marked improvement in all of them (Figure). This online course is now integrated into the internal medicine residency curriculum, and all trainees completed the course by February 2022. Further dissemination is planned to medical schools, residency training programs, and faculty outside of our institution.

Impact of Lighting Assessment and Optimization on Participation and Quality of Life in Individuals with Vision Loss

This pilot study was designed to investigate the effects of a holistic lighting intervention on the quality of life for individuals with low vision. Sixty participants (44 women; median age 69 years) with visual impairment received lighting interventions, including a home visit and consultation in a lighting lab. Assisted by low vision consultants, participants evaluated their performance using the Canadian Occupational Performance Measure (COPM) before and after the intervention. Improvements in visual functioning and quality of life were evaluated using the 39-item National Eye Institute Visual Function Questionnaire (NEI VFQ-39), the Groffman Visual Tracing Test, and the Farnsworth Dichotomous Test (D15). Following the lighting intervention, scores improved for all activities in the COPM (p < 0.01), for near activities and vision-specific role difficulties in the VFQ-39 (p < 0.05), and overall in the D15 test (p < 0.05). These results suggest the intervention provided an effective method for improving the participants’ quality of life and performance.

Assessing the accuracy of an imperfect dichotomous test in a multiple testing context

In this paper we address the situation where a well-established, but invasive, expensive or time-consuming diagnostic test may be replaced by multiple repetitions of a different diagnostic test which is known to be imperfect but less invasive or expensive. With an imperfect diagnostic test repeated several times on the same patient, we first introduce the sensitivity and specificity of that test for any given number of test repetitions. We also derive the corresponding asymptotic limits for sensitivity and specificity as the number n of test repetitions increases. Given those limits, we then derive sharp upper bounds for the differences between the sensitivity and specificity, obtained for a given number n of test repetitions, and the corresponding asymptotic limit. Specifically, we provide exact rates for the convergence of the empirical sensitivities and specificities. Our analysis is motivated, among other things, by the current discussion on rapid SARS-CoV-2 testing where the real-time polymerase chain reaction (RT-PCR) test may be replaced with a sequence of rapid lateral-flow antigen tests.

Spectrum Bias and Individual Strengths of SARS-CoV-2 Serological Tests-A Population-Based Evaluation.

Antibody testing for determining the SARS-CoV-2 serostatus was rapidly introduced in early 2020 and since then has been gaining special emphasis regarding correlates of protection. With limited access to representative samples with known SARS-CoV-2 infection status during the initial period of test development and validation, spectrum bias has to be considered when moving from a “test establishment setting” to population-based settings, in which antibody testing is currently implemented. To provide insights into the presence and magnitude of spectrum bias and to estimate performance measures of antibody testing in a population-based environment, we compared SARS-CoV-2 neutralization to a battery of serological tests and latent class analyses (LCA) in a subgroup (n = 856) of the larger population based TiKoCo-19 cohort (n = 4185). Regarding spectrum bias, we could proof notable differences in test sensitivities and specificities when moving to a population-based setting, with larger effects visible in earlier registered tests. While in the population-based setting the two Roche ELECSYS anti-SARS-CoV-2 tests outperformed every other test and even LCA regarding sensitivity and specificity in dichotomous testing, they didn’t provide satisfying quantitative correlation with neutralization capacity. In contrast, our in-house anti SARS-CoV-2-Spike receptor binding domain (RBD) IgG-ELISA (enzyme-linked-immunosorbant assay) though inferior in dichotomous testing, provided satisfactory quantitative correlation and may thus represent a better correlate of protection. In summary, all tests, led by the two Roche tests, provided sufficient accuracy for dichotomous identification of neutralizing sera, with increasing spectrum bias visible in earlier registered tests, while the majority of tests, except the RBD-ELISA, didn’t provide satisfactory quantitative correlations.