A Methodological Quality Evaluation of Meta-Analyses on Nursing Home Research: Overview and Suggestions for Future Directions

(1) Background: The nursing home (NH) research field lacks quality reporting about meta-analyses (MAs), and most gradings of MA evidence are biased on analyzing the effectiveness of independent variables in randomized control trials. (2) Objectives: This study aimed to perform a critical methodological review of MAs in the NH research field. (3) Methods: We searched the articles from four databases (PubMed, MEDLINE, CINAHL, and PsycINFO) until 15th January 2021. We reviewed a total of 41 published review articles in the NH research field. (4) Results: The studies primarily fell into the following categories: medicine (17/41), nursing (7/41), and psychiatry or psychology (6/41); 36.6% of the reviewed studies did not use any validated MA guidelines. The lowest correctly reported PRISMA 2000 guideline item was protocol and registration (14.6%), and more than 50% of articles did not report risk of bias. Moreover, 78.0% of studies did not describe missing reports of effect size formula. (5) Discussion: NH researchers must follow appropriate and updated guidelines for their MAs in order to provide validated reviews, as well as consider statistical issues such as the complexity of interventions, proper grouping, and scientific effect-size calculations to improve the quality of their study. Future quality review studies should investigate more diverse studies.

A Reanalysis of the Handedness-Mathematics Hypothesis Using Generalized Additive Models

Sala et al. (Front Psychol. 2017;8) investigated the impact of handedness on children’s and adolescents’ performance in mathematics in five independent studies (Total N = 2,314). We concluded that (a) handedness played a nonnegligible role in affecting math ability and (b) its effects were mediated by the difficulty of the mathematical task and the participant’s gender and school level (e.g., primary school vs. high school).However, two statistical issues may have biased these findings. First, polynomial regression is a suboptimal (if not incorrect) option for modeling nonlinear relations between variables. Second, simple linear modeling assumes that the response variable is normally distributed in order to produce accurate estimates. However, mathematical performance did not follow a Gaussian distribution in any of the five studies.The present reanalysis overcomes the above methodological limitations by employing Generalized Additive Models (GAMs). While the significant effect of handedness is often confirmed, the GAMs produce somewhat different results compared to the previous analysis. The implications are discussed.

Statistical Issues in the Estimation of Functional Responses

In this chapter I cover some key issues in fitting functional response models to data and determining the values of parameters. Because some of these issues have been covered elsewhere, here I focus on the nature of foraging trial data and why noise, stochasticity, and individual variation pose particular challenges for understanding functional responses. I examine several data sets to illustrate methods of determining differences in functional response parameters and types. I also show through simulations that individual variation in functional response parameters may account for the noisiness of foraging data and also lead to underestimates of both space clearance rate and handling time in curve-fitting approaches.

488Trial design and statistical considerations for a trial comparing group and individual treatments

Focus of Presentation A randomized clinical trial is considered the best experimental study design for comparing the effect of an intervention against a control. Selecting a trial design depends on the trial objective, a better choice would be a design that provides optimal estimation of the intervention effect, i.e. a design that yields smaller variance for the estimated intervention effect and giving stable estimates. The choice of analysis method depends on trial design aspects, reasonable assumption on the underlying probabilistic model generating the data and the credibility of findings depend on the appropriateness of the analysis method used. Here, we describe a planned randomized standard of care-controlled trial on interactive weekly mobile text messaging added to a motivational interviewing intervention aimed at sustaining continued breastfeeding among women living with HIV in South Africa. Under the “findings” heading, we highlight some of the trial design and statistical issues for discussion at the early career workshop, to gain insights on possible approaches to address the methods issues. Methods and trial design: Women from peri-urban informal settlements and a rural setting will be invited to participate within 24 hours of giving birth at selected primary healthcare facilities. Eligible women will be individually randomized to intervention or control arm after providing written informed consent. The intervention will consist of a weekly text message encouraging women to exclusively breastfeed and inquiring if they have any problems breastfeeding their infants. In addition to text messaging, women assigned to the intervention arm must visit the research site where a research nurse or counsellor will conduct an individual motivational interview, at weeks 2, 6, and 10 post-delivery. Women assigned to the control arm will be counselled by the standard of care service, i.e. primary healthcare nurses and trained counsellors will counsel women to exclusively breastfeed for the first six months through group educational infant feeding counselling sessions. Study participation will not change standard of care of participants, so women assigned to the intervention arm will receive the standard of care service, in line with provincial guidelines applicable in the sector during the study period. The primary outcomes are 1) number of women who are exclusively breastfeeding at week 24 post-delivery and 2) number of women reporting any breastfeeding at week 24 post-delivery. Findings or trial design and statistical issues Although women are individually randomly assigned to intervention and control arms, the standard of care at the primary health care facility may induce a dependency between these participants, also called the group therapy effect. For example, promotion of exclusive breastfeeding in HIV-infected women may be enhanced through positive feedback from women who follow this practice or vice versa. The standard of care will be clustered within group infant feeding counselling session, where participants (both assigned to the control and intervention arm) will receive the standard of care in groups. Women assigned to the intervention arm will receive individual motivational interview and the text messages will be send separately, to each woman’s mobile phone. Implications The trial objective will be to determine whether at week 24 following delivery, weekly text message added to motivational interview leads to better adherence to exclusive breastfeeding and leads to extended breastfeeding than standard of care. Trial design and statistical issues to discuss during the workshop will include a discussion around: 1) the appropriateness of invoking the standard experimental design to address the study objectives, and possible alternatives 2) Sample size estimation for a trial comparing group and individual treatments? 3) Reasonable assumption on the underlying probabilistic model generating the outcome data and 4) Candidate statistical models. Key messages Use of sound statistical principles of experimental design established for clinical trials allow objective and unbiased comparisons.

Image coding by count sample, motivated by the mechanisms of light perception in the human visual system.

The paper presents the results of a study of input video data adequate formation/coding in modern imaging systems. Adequacy is understood here as the maximal correspondence between the ways of the radiation registration by material detectors and the ways of data coding in the retina of the human visual system. In this connection, the paper discusses general statistical issues of (photo) counts photoelectric detection and, on this basis, formalizes the concept of an ideal image formation by (ideal) visualization device. The problems arising in practice when working directly with ideal images are discussed and a method of their reduction to count sample of fixed (controllable) size, which, in fact, constitute the representation (coding) of registered data, is proposed. Results of illustrative computational experiments on count coding of the common digital images given by pixel data are presented. Examples of count samples of different sizes generated for the tested digital image are given. Based on the given results, the dependence of characteristics of sampling representations on the parameter of sample size is discussed.

Rating Norms Should be Calculated from Cumulative Link Mixed Effects Models

Studies which provide norms of Likert ratings typically report per-item summary statistics. Traditionally, these summary statistics comprise the mean and the standard deviation (SD) of the ratings, and the number of observations. Such summary statistics can preserve the rank order of items, but provide distorted estimates of the relative distances between items because of the ordinal nature of Likert ratings. Inter-item relations in such ordinal scales can be more appropriately modelled by cumulative-link mixed effects models (CLMMs). In a series of simulations, and with a reanalysis of an existing rating norms dataset, we show that CLMMs can be used to more accurately norm items, and can provide summary statistics analogous to the traditionally reported means and SDs, but which are disentangled from participants’ response biases. CLMMs can be applied to solve important statistical issues that exist for more traditional analyses of rating norms.

Replicability in Empirical Legal Research

As part of a broader methodological reform movement, scientists are increasingly interested in improving the replicability of their research. Replicability allows others to perform replications to explore potential errors and statistical issues that might call the original results into question. Little attention, however, has been paid to the state of replicability in the field of empirical legal research (ELR). Quality is especially important in this field because empirical legal researchers produce work that is regularly relied upon by courts and other legal bodies. In this review, we summarize the current state of ELR relative to the broader movement toward replicability in the social sciences. As part of that aim, we summarize recent collective replication efforts in ELR and transparency and replicability guidelines adopted by journals that publish ELR. Based on this review, ELR seems to be lagging other fields in implementing reforms. We conclude with suggestions for reforms that might encourage improved replicability. Expected final online publication date for the Annual Review of Law and Social Science, Volume 17 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Barcode sequencing and a high-throughput assay for chronological lifespan uncover ageing-associated genes in fission yeast

Ageing-related processes are largely conserved, with simple organisms remaining the main platform to discover and dissect new ageing-associated genes. Yeasts provide potent model systems to study cellular ageing owing their amenability to systematic functional assays under controlled conditions. Even with yeast cells, however, ageing assays can be laborious and resource-intensive. Here we present improved experimental and computational methods to study chronological lifespan in Schizosaccharomyces pombe. We decoded the barcodes for 3206 mutants of the latest gene-deletion library, enabling the parallel profiling of ~700 additional mutants compared to previous screens. We then applied a refined method of barcode sequencing (Bar-seq), addressing technical and statistical issues raised by persisting DNA in dead cells and sampling bottlenecks in aged cultures, to screen for mutants showing altered lifespan during stationary phase. This screen identified 341 long-lived mutants and 1246 short-lived mutants which point to many previously unknown ageing-associated genes, including 46 conserved but entirely uncharacterized genes. The ageing-associated genes showed coherent enrichments in processes also associated with human ageing, particularly with respect to ageing in non-proliferative brain cells. We also developed an automated colony-forming unit assay to facilitate medium- to high-throughput chronological-lifespan studies by saving time and resources compared to the traditional assay. Results from the Bar-seq screen showed good agreement with this new assay. This study provides an effective methodological platform and identifies many new ageing-associated genes as a framework for analysing cellular ageing in yeast and beyond.

Nassim Taleb: Statistical Concepts and their Philosophical Interpretation

Nassim Nicholas Taleb is an American statistician, mathematician, trader, and essayist of Lebanese descent who, for the most part, adheres to philosophical scepticism. In his works, he primarily considers the problems of chance and probability. Taleb is the author of a number of bestsellers, his book «Black Swan», was included in the review of «The Sunday Times» in the list of the most influential books written after World War II. N. Taleb in his publications adheres to methodological and practical approaches within the modern paradigm of interdisciplinarity, combining, synthesizing scientific vision and tools from different fields of knowledge, primarily in the field of statistical analysis and interpretation of large arrays of statistics. The purpose of this article is to try to highlight some key ideas in the field of statistical methodology and practice, which personally developed or reinterpreted this famous researcher, as well as consideration of individual socio-philosophical views that underlie his diverse scientific and scientific activities. The article considers and analyzes the methodological basis of the concept of rare statistically probable events («black swan»), classification of systems with the separation of «antifragile» subsystems, statistical issues on the use of big data, questions about the possibilities and limitations of forecasting based on time series, some sociological and historiosophical approaches of N. Taleb, as well as theoretical and methodological principles of his concepts in general, which are based on the ideas of philosophical scepticism. Diverse ideas, concepts, approaches, visions, which were expressed by N. Taleb regarding statistics and other sciences in the pages of his books, scientific articles, essays, numerous interviews, etc., in our opinion, need a more in-depth, multifaceted study. Such explorations can be useful and productive for theoretical science and practical application in modern Ukraine, including in the field of statistics.