(To watch the full press conference with sign language interpretation, click here.)

Chief Executive Carrie Lam today said because Hong Kong has not reported a local COVID-19 case for over two weeks and imported cases are low, some anti-epidemic measures can be lifted.

During a press conference, Mrs Lam outlined that unlike some European countries, Hong Kong did not need to go into lockdown to contain the spread of the disease.

“Hong Kong has never gone into a stage of a complete city lockdown. In some of the European countries where they practise a city lockdown, residents are simply not allowed to leave their homes, except for some very essential purposes. But we have never adopted that practice.

“And in fact, many renowned experts are now trying to study our situation - why does Hong Kong succeed in keeping the confirmed cases at a low level without drastic measures like a complete city lockdown. And I do think that is a very interesting topic for further research.”

Mrs Lam noted that the Government had adopted the “suppress and lift” strategy under which restrictions are implemented and lifted in accordance with the infection situation.

“The strategy that Hong Kong has been adopting - and advocated by some of our experts - is what we call a ‘suppress and lift strategy’.

“So in light of the number of confirmed cases and likelihood of the spread of the disease in the community, we will have to suppress in order to make sure that there will be no surge in the number of confirmed cases as we have seen in some neighbouring regions.

“When the situation of the infection stabilises, that is the time for lifting, that is, loosening a bit so that society can operate more normally, especially for the businesses and for individuals’ behaviour.”

The Chief Executive said the Government still needed to monitor the COVID-19 situation closely, even though it was in the stage of lifting restrictions.

“We are now right in the stage of lifting because we have not had a local case for 16 days already and the number of imported cases is very, very low.

“We are now quite confident that the system of testing and holding that we have put in place for all arrivals from overseas would enable us to control the number of imported cases. So this is a time for lifting and this afternoon we have announced a number of lifting measures.

“If the situation continues to stay at the current level - no local cases, very few imported cases - then at the end of the 14-day period, that is May 22, of course that would be the time for more relaxation.”

Mrs Lam added that if a local case suddenly surfaced, Hong Kong may have to go back to some suppression measures, which was why the Government had to monitor the situation closely so it could take the necessary and pertinent response measures.

(To watch the full press conference with sign language interpretation, click here.)

The relaxation of anti-epidemic measures is a step in the right direction, Chief Executive Carrie Lam said today.

Mrs Lam made the statement at a press conference this afternoon.

She said the Government will relax the requirement limiting group gatherings in public places to a maximum of four people. Starting from Friday, up to eight people can gather in public places.

"So raising the number from four to eight for the catering business and also for the prohibition against group gatherings under Cap 599G is not an exact science, but this is a step in the right direction of relaxation.

"Maybe in another 14 days’ time we will raise the number of eight to 10, to 12, to 15 and so on."

Regarding bars and pubs, Mrs Lam said these venues will be able to reopen but the Government will put in place requirements to prevent physical interactions.

"We have decided that perhaps to strike a pragmatic balance is to allow them to reopen for business but to put in far more stringent requirements."

Such requirements include no live music, band performances or dancing in bar premises.

"That would be another way to keep the social distance and prevent as much as possible physical interactions."

Click here for the latest measures.

What impact has the lockdown had on our mental health, and what determines how people cope with isolation?

It is possible that the next time you walk into a bar you may find that there is only standing room, and you are among a handful of persons allowed inside. Prime Minister Andrew Holness said that in addition to having a specific gathering rule,...

Invitation Only Research Event

Event participants

Beyza Unal, Senior Research Fellow, International Security Department, Chatham House
Patricia Lewis, Research Director, International Security Department, Chatham House

The PET radiotracer ⁶⁸Ga-PSMA-HBED-CC (⁶⁸Ga-PSMA-11) shows potential as an imaging biomarker for recurrent and metastatic prostate cancer. The purpose of this study was to determine repeatability of ⁶⁸Ga-PSMA-HBED-CC in a test-retest trial in subjects with metastatic prostate adenocarcinoma. Methods: Subjects with metastatic prostate cancer underwent two PET/CT scans with ⁶⁸Ga-PSMA-HBED-CC within 14 days (mean 6 ± 4 d). Lesions in bone, nodes, prostate/bed, and visceral organs as well as representative normal tissues (salivary glands and spleen) were segmented separately by two readers. Absolute and percent differences in SUV_max and SUVmean were calculated for all test-retest regions. Repeatability was assessed using percentage difference, within-subject coefficient of variation (wCV), repeatability coefficient (RC), and Bland-Altman analysis. Results: 18 subjects were evaluated, 16 of which demonstrated local or metastatic disease on ⁶⁸Ga-PSMA-HBED-CC PET/CT. A total of 136 lesions were segmented in bone (n = 99), nodes (n = 27), prostate/bed (n = 7), and viscera (n = 3). The wCV for SUV_max was 11.7% for bone lesions and 13.7% for nodes. The RC was ±32.5% SUV_max for bone lesions and ±37.9% SUV_max for nodal lesions, meaning 95% of the normal variability between two measurements will be within these numbers, so larger differences are likely attributable to true biological changes in tumor rather than normal physiologic or measurement variability. wCV in the salivary glands and spleen was 8.9% and 10.7% SUVmean, respectively. Conclusion: Repeatability measurements for PET/CT test-retest with ⁶⁸Ga-PSMA-HBED-CC show a wCV 12-14% SUV_max and RC ±33-38% SUV_max in bone and nodal lesions. These estimates are an important aspect of ⁶⁸Ga-PSMA-HBED-CC as a quantitative imaging biomarker. These estimates are similar to those reported for ¹⁸F-FDG, suggesting that ⁶⁸Ga-PSMA-HBED-CC PET/CT may be useful in monitoring response to therapy.

Quantitative evaluation of radiolabeled Prostate-Specific Membrane Antigen (PSMA) PET scans may be used to monitor treatment response in patients with prostate cancer (PCa). To interpret longitudinal differences in PSMA uptake, the intrinsic variability of tracer uptake in PCa lesions needs to be defined. The aim of this study was to investigate the repeatability of quantitative ¹⁸F-DCFPyL (a second generation ¹⁸F-PSMA-ligand) PET/CT measurements in patients with PCa. Methods: Twelve patients with metastatic PCa were prospectively included, of which 2 were excluded from final analyses. Patients received two whole-body ¹⁸F-DCFPyL PET/CT scans (median dose 317 MBq; uptake time 120 min), within median 4 days (range 1-11 days). After semi-automatic (isocontour-based) tumor delineation, the following lesion-based metrics were derived: Tumor-to-Blood ratio (TBRmean, TBRpeak, and TBRmax), Standardized Uptake Value (SUVmean, SUVpeak, SUV_max, normalized to bodyweight), tumor volume, and total lesion tracer uptake (TLU). Additionally, patient-based Total Tumor Volume (sum of PSMA-positive tumor volumes; TTV) and Total Tumor Burden (sum of all lesion TLUs; TTB) were derived. Repeatability was analyzed using repeatability coefficients (RC) and intra-class correlations (ICC). Additionally, the effect of point spread function (PSF) image reconstruction on the repeatability of uptake metrics was evaluated. Results: In total, 36 ¹⁸F-DCFPyL PET positive lesions were analyzed (up to 5 lesions per patient). RCs of TBRmean, TBRpeak, and TBRmax were 31.8%, 31.7%, and 37.3%, respectively. For SUVmean, SUVpeak, SUV_max the RCs were 24.4%, 25.3% and 31.0%, respectively. All ICC were ≥0.97. Tumor volume delineations were well repeatable, with RC 28.1% for individual lesion volumes and RC 17.0% for TTV. TTB had a RC of 23.2% and 33.4%, when based on SUVmean and TBRmean, respectively. Small lesions (<4.2mL) had worse repeatability for volume measurements. The repeatability of SUVpeak, TLU, and all patient-level metrics were not affected by PSF-reconstruction. Conclusion: ¹⁸F-DCFPyL uptake measurements are well repeatable and can be used for clinical validation in future treatment response assessment studies. Patient-based TTV may be preferred for multicenter studies since its repeatability was both high and robust to different image reconstructions.

Background: Functional magnetic resonance imaging (fMRI) studies have reported altered integrity of large-scale neurocognitive networks (NCNs) in dementing disorders. However, findings on specificity of these alterations in patients with Alzheimer’s disease (AD) and behavioral variant frontotemporal dementia (bvFTD) are still very limited. Recently, NCNs have been successfully captured using positron emission tomography (PET) with F18-fluordesoxyglucose (FDG). Methods: Network integrity was measured in 72 individuals (38 male) with mild AD, bvFTD, and healthy controls using a simultaneous resting state fMRI and FDG-PET. Indices of network integrity were calculated for each subject, network, and imaging modality. Results: In either modality, independent component analysis revealed four major NCNs: anterior default mode network (DMN), posterior DMN, salience network, and right central executive network (CEN). In fMRI data, integrity of posterior DMN was found to be significantly reduced in both patient groups relative to controls. In the AD group anterior DMN and CEN appeared to be additionally affected. In PET data, only integrity of posterior DMN in patients with AD was reduced, while three remaining networks appeared to be affected only in patients with bvFTD. In a logistic regression analysis, integrity of anterior DMN as measured with PET alone accurately differentiated between the patient groups. A correlation between indices of two imaging modalities was overall low. Conclusion: FMRI and FDG-PET capture partly different aspects of network integrity. A higher disease specificity of NCNs as derived from PET data supports metabolic connectivity imaging as a promising diagnostic tool.

As the capability of mass spectrometry-based proteomics has matured, tens of thousands of peptides can be measured simultaneously, which has the benefit of offering a systems view of protein expression. However, a major challenge is that with an increase in throughput, protein quantification estimation from the native measured peptides has become a computational task. A limitation to existing computationally-driven protein quantification methods is that most ignore protein variation, such as alternate splicing of the RNA transcript and post-translational modifications or other possible proteoforms, which will affect a significant fraction of the proteome. The consequence of this assumption is that statistical inference at the protein level, and consequently downstream analyses, such as network and pathway modeling, have only limited power for biomarker discovery. Here, we describe a Bayesian model (BP-Quant) that uses statistically derived peptides signatures to identify peptides that are outside the dominant pattern, or the existence of multiple over-expressed patterns to improve relative protein abundance estimates. It is a research-driven approach that utilizes the objectives of the experiment, defined in the context of a standard statistical hypothesis, to identify a set of peptides exhibiting similar statistical behavior relating to a protein. This approach infers that changes in relative protein abundance can be used as a surrogate for changes in function, without necessarily taking into account the effect of differential post-translational modifications, processing, or splicing in altering protein function. We verify the approach using a dilution study from mouse plasma samples and demonstrate that BP-Quant achieves similar accuracy as the current state-of-the-art methods at proteoform identification with significantly better specificity. BP-Quant is available as a MatLab ® and R packages at https://github.com/PNNL-Comp-Mass-Spec/BP-Quant.

The UK’s austerity programme has disproportionately affected children and people with disabilities, says David Taylor-Robinson, a senior clinical lecturer in public health at the University of Liverpool. He joins us to discuss why the evidence shows the vulnerable are hit hardest by the cuts to public services, despite the UN conventions on...

Gina Agiostratidou
Dec 1, 2017; 40:1622-1630
Continuous Glucose Monitoring and Risk of Hypoglycemia

The Dental Quality Alliance will help dentists learn more about how quality measure domains can be best used to drive quality improvement at the practice level through a free webinar in March.

Here's a question with three different answers. The first answer is derived from arithmetic. The second comes from common sense. The third is based on psychology.

WASHINGTON – The federal Every Student Succeeds Act of 2015 (ESSA) requires states to publicly report annual performance and graduation rates for students in a range of areas, breaking out results for subgroups with unique characteristics, including English Learners (ELs). The objective is to help schools identify and close achievement gaps experienced by historically underserved groups of students.

Huy A. Tran
Jul 1, 2004; 22:141-143
Case Studies

Teachers and other education advocates hope that tax-wary voters will be willing to approve an amendment that would pour more than $1.6 billion more into schools each year.

This researchprojectimplemented a randomizedcontrolledtrial ofthe SEAM program in Terms 3 and 4 ofthe 2016 school year. The purpose of the study was to determine the effects of the SEAM program. The study enrolled 448 treatment group students who were referred to SATOs for potential SEAM intervention, and 448 matched control group students who were not referred to SATOs. Approximately one-third of treatment group students received a compulsory conference notice, approximately one-third of treatment students' families signed an attendance plan, about 20% had a compulsory conference take place, and payment was suspended for approximately 5% of treatment students. No significant differences following any of these interventions were observed between treatment and control students.

Florida lawmakers sent Gov. Ron DeSantis a Republican-crafted bill last week to create a new voucher program for students to attend private schools, including religious ones, using taxpayer dollars traditionally spent on public schools.

England : Society of Medical Officers of Health, [192-?]

Xianzheng Huang, Haiming Zhou.

Source: Electronic Journal of Statistics, Volume 14, Number 1, 970--1023.

Abstract:
We consider estimating the density of a response conditioning on an error-prone covariate. Motivated by two existing kernel density estimators in the absence of covariate measurement error, we propose a method to correct the existing estimators for measurement error. Asymptotic properties of the resultant estimators under different types of measurement error distributions are derived. Moreover, we adjust bandwidths readily available from existing bandwidth selection methods developed for error-free data to obtain bandwidths for the new estimators. Extensive simulation studies are carried out to compare the proposed estimators with naive estimators that ignore measurement error, which also provide empirical evidence for the effectiveness of the proposed bandwidth selection methods. A real-life data example is used to illustrate implementation of these methods under practical scenarios. An R package, lpme, is developed for implementing all considered methods, which we demonstrate via an R code example in Appendix B.2.

Jun Zhang, Yujie Gai, Xia Cui, Gaorong Li.

Source: Brazilian Journal of Probability and Statistics, Volume 34, Number 2, 370--393.

Abstract:
This paper studies the measure of symmetry or asymmetry of a continuous variable under the multiplicative distortion measurement errors setting. The unobservable variable is distorted in a multiplicative fashion by an observed confounding variable. First, two direct plug-in estimation procedures are proposed, and the empirical likelihood based confidence intervals are constructed to measure the symmetry or asymmetry of the unobserved variable. Next, we propose four test statistics for testing whether the unobserved variable is symmetric or not. The asymptotic properties of the proposed estimators and test statistics are examined. We conduct Monte Carlo simulation experiments to examine the performance of the proposed estimators and test statistics. These methods are applied to analyze a real dataset for an illustration.

Luisa Rivas, Manuel Galea.

Source: Brazilian Journal of Probability and Statistics, Volume 33, Number 2, 402--424.

Abstract:
In this paper, we present a regression model where the response variable is a count data that follows a Waring distribution. The Waring regression model allows for analysis of phenomena where the Geometric regression model is inadequate, because the probability of success on each trial, $p$, is different for each individual and $p$ has an associated distribution. Estimation is performed by maximum likelihood, through the maximization of the $Q$-function using EM algorithm. Diagnostic measures are calculated for this model. To illustrate the results, an application to real data is presented. Some specific details are given in the Appendix of the paper.

Björn Böttcher, Martin Keller-Ressel, René L. Schilling.

Source: The Annals of Statistics, Volume 47, Number 5, 2757--2789.

Abstract:
We introduce two new measures for the dependence of $nge2$ random variables: distance multivariance and total distance multivariance . Both measures are based on the weighted $L^{2}$-distance of quantities related to the characteristic functions of the underlying random variables. These extend distance covariance (introduced by Székely, Rizzo and Bakirov) from pairs of random variables to $n$-tuplets of random variables. We show that total distance multivariance can be used to detect the independence of $n$ random variables and has a simple finite-sample representation in terms of distance matrices of the sample points, where distance is measured by a continuous negative definite function. Under some mild moment conditions, this leads to a test for independence of multiple random vectors which is consistent against all alternatives.

Yen-Chi Chen.

Source: The Annals of Statistics, Volume 47, Number 4, 2174--2203.

Abstract:
In this paper we study the $alpha $-cluster tree ($alpha $-tree) under both singular and nonsingular measures. The $alpha $-tree uses probability contents within a set created by the ordering of points to construct a cluster tree so that it is well defined even for singular measures. We first derive the convergence rate for a density level set around critical points, which leads to the convergence rate for estimating an $alpha $-tree under nonsingular measures. For singular measures, we study how the kernel density estimator (KDE) behaves and prove that the KDE is not uniformly consistent but pointwise consistent after rescaling. We further prove that the estimated $alpha $-tree fails to converge in the $L_{infty }$ metric but is still consistent under the integrated distance. We also observe a new type of critical points—the dimensional critical points (DCPs)—of a singular measure. DCPs are points that contribute to cluster tree topology but cannot be defined using density gradient. Building on the analysis of the KDE and DCPs, we prove the topological consistency of an estimated $alpha $-tree.

Anton Thalmaier, James Thompson.

Source: Bernoulli, Volume 26, Number 3, 2202--2225.

Abstract:
In this article, we derive moment estimates, exponential integrability, concentration inequalities and exit times estimates for canonical diffusions firstly on sub-Riemannian limits of Riemannian foliations and secondly in the nonsmooth setting of $operatorname{RCD}^{*}(K,N)$ spaces. In each case, the necessary ingredients are Itô’s formula and a comparison theorem for the Laplacian, for which we refer to the recent literature. As an application, we derive pointwise Carmona-type estimates on eigenfunctions of Schrödinger operators.

Nhat Ho, XuanLong Nguyen, Ya’acov Ritov.

Source: Bernoulli, Volume 26, Number 2, 828--857.

Abstract:
In finite mixture models, apart from underlying mixing measure, true kernel density function of each subpopulation in the data is, in many scenarios, unknown. Perhaps the most popular approach is to choose some kernel functions that we empirically believe our data are generated from and use these kernels to fit our models. Nevertheless, as long as the chosen kernel and the true kernel are different, statistical inference of mixing measure under this setting will be highly unstable. To overcome this challenge, we propose flexible and efficient robust estimators of the mixing measure in these models, which are inspired by the idea of minimum Hellinger distance estimator, model selection criteria, and superefficiency phenomenon. We demonstrate that our estimators consistently recover the true number of components and achieve the optimal convergence rates of parameter estimation under both the well- and misspecified kernel settings for any fixed bandwidth. These desirable asymptotic properties are illustrated via careful simulation studies with both synthetic and real data.

Jing Lei.

Source: Bernoulli, Volume 26, Number 1, 767--798.

Abstract:
We provide upper bounds of the expected Wasserstein distance between a probability measure and its empirical version, generalizing recent results for finite dimensional Euclidean spaces and bounded functional spaces. Such a generalization can cover Euclidean spaces with large dimensionality, with the optimal dependence on the dimensionality. Our method also covers the important case of Gaussian processes in separable Hilbert spaces, with rate-optimal upper bounds for functional data distributions whose coordinates decay geometrically or polynomially. Moreover, our bounds of the expected value can be combined with mean-concentration results to yield improved exponential tail probability bounds for the Wasserstein error of empirical measures under Bernstein-type or log Sobolev-type conditions.

Andrea Cremaschi, Raffaele Argiento, Katherine Shoemaker, Christine Peterson, Marina Vannucci.

Source: Bayesian Analysis, Volume 14, Number 4, 1271--1301.

Abstract:
Gaussian graphical models are useful tools for exploring network structures in multivariate normal data. In this paper we are interested in situations where data show departures from Gaussianity, therefore requiring alternative modeling distributions. The multivariate $t$ -distribution, obtained by dividing each component of the data vector by a gamma random variable, is a straightforward generalization to accommodate deviations from normality such as heavy tails. Since different groups of variables may be contaminated to a different extent, Finegold and Drton (2014) introduced the Dirichlet $t$ -distribution, where the divisors are clustered using a Dirichlet process. In this work, we consider a more general class of nonparametric distributions as the prior on the divisor terms, namely the class of normalized completely random measures (NormCRMs). To improve the effectiveness of the clustering, we propose modeling the dependence among the divisors through a nonparametric hierarchical structure, which allows for the sharing of parameters across the samples in the data set. This desirable feature enables us to cluster together different components of multivariate data in a parsimonious way. We demonstrate through simulations that this approach provides accurate graphical model inference, and apply it to a case study examining the dependence structure in radiomics data derived from The Cancer Imaging Atlas.

Barbara J. Weiland
Jan 28, 2015; 35:1505-1512
Neurobiology of Disease

In the year 2000, the UN Member States set the eight Millennium Development Goals. One of the most ambitious was to eradicate extreme poverty and hunger. As part of this goal, the United Nations General Assembly set a target to halve the proportion of people who suffer from hunger by 2015.  But have you ever wondered how hunger is measured in [...]

Speech by Mr Stefan Ingves, Governor of the Sveriges Riksbank, at the Sveriges Riksbank, Stockholm, 3 April 2020.

FSI Briefs No 4, April 2020. Currently, insurers are more likely to experience losses from financial market volatility than from higher insurance claims arising from Covid-19. Few insurance supervisors have seen a need to strengthen or adjust prudential requirements to insulate insurers from current financial market uncertainties. So far, authorities have responded mainly by taking measures to provide operational relief to insurers from regulatory and supervisory requirements so that they can continue providing insurance services. These measures will also help insurers to enhance risk monitoring of their Covid-19 financial exposures. Some authorities have set out expectations for insurers to conserve capital through prudent exercise of dividend and variable remuneration policies. The aim is to enhance their resilience against huge uncertainties from potential Covid-19 fallout. Other capital-related measures should relieve supervisory pressures and reduce the tendency of insurers to manage their investments in a procyclical manner. These measures include: extending the supervisory intervention ladder, triggering the countercyclical lever and recalibrating capital requirements. The far-reaching impact of Covid-19 calls for sustained vigilance by both supervisors and insurers. In the post-pandemic phase, the extraordinary measures currently warranted will need to be unwound through a carefully crafted exit strategy that preserves sound risk management practices and protects policyholders' interests.

BCBS Press release "Basel Committee sets out additional measures to alleviate the impact of Covid-19", 3 April 2020

With the business world -- and the world at large, for that matter -- changing at what feels like a moment's notice, businesses and brands have never been required to be as limber as in this current moment. Marketing leaders want hard evidence and objective facts for decision making. It wasn't long ago that multi-touch attribution was the prized child of the hype cycle among marketers.

The new reality of life under COVID-19 means Montreal Alouettes GM Danny Maciocia will be physically alone in his basement while he and his staff participate in the CFL draft.

While millions of people have taken advantage of easing coronavirus lockdowns to enjoy the outdoors, some of the world’s most populous countries have reported worrying new peaks in infections.

Scotland's crime levels have dropped by around 25% since lockdown measures were introduced.

A group of testing experts says that opt-out could jeopardize the ability to target educational resources appropriately.

There are known gaps in quality measures for children. More clinical effectiveness research is needed. The patient-centered medical home may serve as a model to guide the development of quality measures, particularly for children with complex medical conditions.

This study combined systematic literature review and the Rand/University of California Los Angeles appropriateness method to develop quality measures for children with complex medical conditions. These are valid and feasible quality measures based on the patient-centered medical home framework that may be used to assess care. (Read the full article)

The availability of rapid response systems to assist deteriorating patients is the standard of care in children’s hospitals. Metrics for evaluating their effectiveness include cardiac and respiratory arrest rates, rare events that require years of data to show significant improvements.

A proximate outcome for in-hospital mortality among patients receiving rapid response system assistance was developed. This "critical deterioration" metric was eightfold more common than arrests and demonstrated criterion and construct validity, facilitating meaningful evaluation over shorter periods of time. (Read the full article)

Transcutaneous bilirubinometry was originally developed as a potential replacement for invasive blood sampling, but its clinical application is still limited to a screening method for hyperbilirubinemia. Reasons for this limited clinical value may be diverse.

This study provides insight into the reasons for the limited clinical value of transcutaneous bilirubinometry. This aids to both better interpretation of the measured TcB value from a patient and to possible improvement of the clinical value of the technique. (Read the full article)

Healthcare Effectiveness Data and Information Set (HEDIS) measures are widely used to assess the reliability of pediatric immunization delivery. The extent to which these measures provide accurate ("is this child up-to-date on immunizations?") and useful ("is this child due for catch-up immunizations?") information is unclear.

Overall, HEDIS childhood immunization measures are accurate and useful. Users of HEDIS data should be aware, however, that certain immunizations (eg, hepatitis B, pneumococcal conjugate) and children (eg, those with a single overdue immunization) are more prone to HEDIS misclassification. (Read the full article)

As a result of safety and environmental concerns about mercury, aneroid sphygmomanometers have replaced mercury-filled devices for blood pressure measurements. Despite this change, few studies have compared the 2 devices.

Little clinical variation exists between blood pressure measurements obtained from an aneroid or mercury device, suggesting that either device could be used in a research or clinical setting. (Read the full article)