scholarly journals Evaluating the Effectiveness of Vaccines Using a Regression Discontinuity Design

2019 ◽  
Vol 188 (6) ◽  
pp. 987-990
Author(s):  
Nicole E Basta ◽  
M Elizabeth Halloran
Keyword(s):  
Randomized Clinical Trials ◽  
Regression Discontinuity ◽  
Control Strategies ◽  
Regression Discontinuity Design ◽  
Vaccination Programs ◽  
Wide Range ◽  
Quasi Experimental ◽  
Psychology Literature ◽  
And Control ◽  
The Impact

Abstract The regression discontinuity design (RDD), first proposed in the educational psychology literature and popularized in econometrics in the 1960s, has only recently been applied to epidemiologic research. A critical aim of infectious disease epidemiologists and global health researchers is to evaluate disease prevention and control strategies, including the impact of vaccines and vaccination programs. RDDs have very rarely been used in this context. This quasi-experimental approach using observational data is designed to quantify the effect of an intervention when eligibility for the intervention is based on a defined cutoff such as age or grade in school, making it ideally suited to estimating vaccine effects given that many vaccination programs and mass-vaccination campaigns define eligibility in this way. Here, we describe key features of RDDs in general, then specific scenarios, with examples, to illustrate that RDDs are an important tool for advancing our understanding of vaccine effects. We argue that epidemiologic researchers should consider RDDs when evaluating interventions designed to prevent and control diseases. This approach can address a wide range of research questions, especially those for which randomized clinical trials would present major challenges or be infeasible. Finally, we propose specific ways in which RDDs could advance future vaccine research.

scholarly journals The malleability of intelligence: the effects of schooling, genetic factors, socioeconomic status, and their interplay in children.

2021 ◽  
Author(s):  
Nicholas Judd ◽  
Bruno Sauce ◽  
Torkel Klingberg
Keyword(s):  
Socioeconomic Status ◽  
Working Memory ◽  
Genetic Factors ◽  
Fluid Intelligence ◽  
Regression Discontinuity ◽  
Regression Discontinuity Design ◽  
Quasi Experimental ◽  
Independent Effects ◽  
Main Effects ◽  
The Impact

Schooling, socioeconomic status (SES), and genetics all play large roles in intelligence differences. However, it is unclear to what extent their contributions are unique and if they interact. Here we used a multitrait polygenic score for cognition (cog-PGS) with a quasi-experimental regression discontinuity design to isolate how months of schooling relate to intelligence in 7,853 children (aged 9-11). We found large, independent effects of schooling, cog-PGS, and SES on working memory, crystallized (cIQ), and fluid intelligence (fIQ). Intriguingly, we found evidence for gene-by-environment interplay between cog-PGS and SES for cIQ, and a trend in the same direction for fIQ. This interaction was negative meaning that the intelligence of the highest SES children was the least affected by genetic differences, while the lowest SES children were most affected by genetic variability. Schooling showed no interaction with cog-PGS or SES for the three intelligence domains tested. While schooling had strong main effects on intelligence, it did not lessen, nor widen the impact of these preexisting SES or genetic factors.

scholarly journals Estimating asymptomatic, undetected and total cases for the COVID-19 outbreak in Wuhan: a mathematical modeling study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Xi Huo ◽  
Jing Chen ◽  
Shigui Ruan
Keyword(s):  
Disease Transmission ◽  
Large Scale ◽  
Transmission Rate ◽  
Control Strategies ◽  
Herd Immunity ◽  
Antibody Prevalence ◽  
Screening Process ◽  
Vaccination Programs ◽  
Prevalence Level ◽  
The Impact

Abstract Background The COVID-19 outbreak in Wuhan started in December 2019 and was under control by the end of March 2020 with a total of 50,006 confirmed cases by the implementation of a series of nonpharmaceutical interventions (NPIs) including unprecedented lockdown of the city. This study analyzes the complete outbreak data from Wuhan, assesses the impact of these public health interventions, and estimates the asymptomatic, undetected and total cases for the COVID-19 outbreak in Wuhan. Methods By taking different stages of the outbreak into account, we developed a time-dependent compartmental model to describe the dynamics of disease transmission and case detection and reporting. Model coefficients were parameterized by using the reported cases and following key events and escalated control strategies. Then the model was used to calibrate the complete outbreak data by using the Monte Carlo Markov Chain (MCMC) method. Finally we used the model to estimate asymptomatic and undetected cases and approximate the overall antibody prevalence level. Results We found that the transmission rate between Jan 24 and Feb 1, 2020, was twice as large as that before the lockdown on Jan 23 and 67.6% (95% CI [0.584,0.759]) of detectable infections occurred during this period. Based on the reported estimates that around 20% of infections were asymptomatic and their transmission ability was about 70% of symptomatic ones, we estimated that there were about 14,448 asymptomatic and undetected cases (95% CI [12,364,23,254]), which yields an estimate of a total of 64,454 infected cases (95% CI [62,370,73,260]), and the overall antibody prevalence level in the population of Wuhan was 0.745% (95% CI [0.693%,0.814%]) by March 31, 2020. Conclusions We conclude that the control of the COVID-19 outbreak in Wuhan was achieved via the enforcement of a combination of multiple NPIs: the lockdown on Jan 23, the stay-at-home order on Feb 2, the massive isolation of all symptomatic individuals via newly constructed special shelter hospitals on Feb 6, and the large scale screening process on Feb 18. Our results indicate that the population in Wuhan is far away from establishing herd immunity and provide insights for other affected countries and regions in designing control strategies and planing vaccination programs.

scholarly journals Wolbachia: endosymbiont of onchocercid nematodes and their vectors

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Ranju Ravindran Santhakumari Manoj ◽  
Maria Stefania Latrofa ◽  
Sara Epis ◽  
Domenico Otranto
Keyword(s):  
Control Strategies ◽  
Molecular Data ◽  
Scientific Data ◽  
Growth And Survival ◽  
Vector Borne Diseases ◽  
Wide Range ◽  
Veterinary Importance ◽  
Wolbachia Endosymbiont ◽  
Vector Borne ◽  
And Control

Abstract Background Wolbachia is an obligate intracellular maternally transmitted, gram-negative bacterium which forms a spectrum of endosymbiotic relationships from parasitism to obligatory mutualism in a wide range of arthropods and onchocercid nematodes, respectively. In arthropods Wolbachia produces reproductive manipulations such as male killing, feminization, parthenogenesis and cytoplasmic incompatibility for its propagation and provides an additional fitness benefit for the host to protect against pathogens, whilst in onchocercid nematodes, apart from the mutual metabolic dependence, this bacterium is involved in moulting, embryogenesis, growth and survival of the host. Methods This review details the molecular data of Wolbachia and its effect on host biology, immunity, ecology and evolution, reproduction, endosymbiont-based treatment and control strategies exploited for filariasis. Relevant peer-reviewed scientic papers available in various authenticated scientific data bases were considered while writing the review. Conclusions The information presented provides an overview on Wolbachia biology and its use in the control and/or treatment of vectors, onchocercid nematodes and viral diseases of medical and veterinary importance. This offers the development of new approaches for the control of a variety of vector-borne diseases. Graphic Abstract

scholarly journals Effectiveness of a Power Factor Correction Policy in Improving the Energy Efficiency of Large-Scale Electricity Users in Ghana

Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2582 ◽  
Author(s):  
Samuel Lotsu ◽  
Yuichiro Yoshida ◽  
Katsufumi Fukuda ◽  
Bing He
Keyword(s):  
Energy Efficiency ◽  
Power Factor ◽  
Large Scale ◽  
Regression Discontinuity ◽  
Power Factor Correction ◽  
Energy Crisis ◽  
Regression Discontinuity Design ◽  
The Government ◽  
Power Factor Improvement ◽  
The Impact

Confronting an energy crisis, the government of Ghana enacted a power factor correction policy in 1995. The policy imposes a penalty on large-scale electricity users, namely, special load tariff (SLT) customers of the Electricity Company of Ghana (ECG), whose power factor is below 90%. This paper investigates the impact of this policy on these firms’ power factor improvement by using panel data from 183 SLT customers from 1994 to 1997 and from 2012. To avoid potential endogeneity, this paper adopts a regression discontinuity design (RDD) with the power factor of the firms in the previous year as a running variable, with its cutoff set at the penalty threshold. The result shows that these large-scale electricity users who face the penalty because their power factor falls just short of the threshold are more likely to improve their power factor in the subsequent year, implying that the power factor correction policy implemented by Ghana’s government is effective.

scholarly journals The Effect of Music Therapy on Problem-Solving Skills

2016 ◽  
Vol 6 (2) ◽  
pp. 169
Author(s):  
Zeinab Sirous Jahedi ◽  
Nasser Amini Khoi
Keyword(s):  
Problem Solving ◽  
Music Therapy ◽  
Sampling Method ◽  
Average Score ◽  
Control Group ◽  
Problem Solving Skills ◽  
Statistical Population ◽  
Quasi Experimental ◽  
And Control ◽  
The Impact

<p>The aim of the present research was study of the impact of music therapy on problem-solving skills of 4 to 6 years old children in Tehran. This research was a quasi-experimental study with pretest-posttest control group. The statistical population was all 4 to 6 years old children in region 2 of Tehran. Using the random sampling method, the study sample was chosen in two experiment (15 individuals) and control (15 individuals) groups.   The experiment group received 12 sessions of music therapy and the control group was waiting for treatment meanwhile. To evaluate the problem-solving skill in children, the three subscales of Wechsler’s Preschool and Primary Scale of Intelligence (WPPSI) were used, including: mazes, cubes and arithmetic.  Analysis of data obtained from the questionnaires was conducted in two parts of descriptive and inferential. The data analysis indicated the significant increase of problem-solving average score of the experiment group compared to the control group.</p>

scholarly journals Elections and the Regression Discontinuity Design: Lessons from Close U.S. House Races, 1942–2008

2011 ◽  
Vol 19 (4) ◽  
pp. 385-408 ◽  
Author(s):  
Devin Caughey ◽  
Jasjeet S. Sekhon
Keyword(s):  
Regression Discontinuity ◽  
Covariate Adjustment ◽  
Regression Discontinuity Design ◽  
Present Evidence ◽  
Model Based ◽  
Covariate Balance ◽  
Ex Ante ◽  
And Control

Following David Lee's pioneering work, numerous scholars have applied the regression discontinuity (RD) design to popular elections. Contrary to the assumptions of RD, however, we show that bare winners and bare losers in U.S. House elections (1942–2008) differ markedly on pretreatment covariates. Bare winners possess largeex antefinancial, experience, and incumbency advantages over their opponents and are usually the candidates predicted to win byCongressional Quarterly's pre-election ratings. Covariate imbalance actually worsens in the closest House elections. National partisan tides help explain these patterns. Previous works have missed this imbalance because they rely excessively on model-based extrapolation. We present evidence suggesting that sorting in close House elections is due mainly to activities on or before Election Day rather than postelection recounts or other manipulation. The sorting is so strong that it is impossible to achieve covariate balance between matched treated and control observations, making covariate adjustment a dubious enterprise. Although RD is problematic for postwar House elections, this example does highlight the design's advantages over alternatives: RD's assumptions are clear and weaker than model-based alternatives, and their implications are empirically testable.

scholarly journals A regression discontinuity analysis of the social distancing recommendations for older adults in Sweden during COVID-19

2021 ◽  
Author(s):  
Carl Bonander ◽  
Debora Stranges ◽  
Johanna Gustavsson ◽  
Matilda Almgren ◽  
Malin Inghammar ◽  
...  
Keyword(s):  
Older Adults ◽  
Regression Discontinuity ◽  
Model Specification ◽  
Regression Discontinuity Design ◽  
Sharp Drop ◽  
Social Distancing ◽  
Disease Outcomes ◽  
The Social ◽  
National Register Data ◽  
The Impact

Objectives: To study the impact of non-mandatory, age-specific social distancing recommendations for older adults (70+ years) in Sweden on isolation behaviors and disease outcomes during the first wave of the COVID-19 pandemic. Methods: Our study relies on self-reported isolation data from COVID Symptom Study Sweden (n = 96,053) and national register data on COVID-19 hospitalizations, deaths, and confirmed cases. We use a regression discontinuity design to account for confounding factors, exploiting the fact that exposure to the recommendation was a discontinuous function of age. Results: By comparing individuals just above to those just below the age limit for the policy, our analyses revealed a sharp drop in the weekly number of visits to crowded places at the 70-year-threshold (-13%). Severe COVID-19 cases (hospitalizations or deaths) also dropped abruptly by 16% at the 70-year-threshold. Our data suggest that the age-specific recommendations prevented approximately 1,800 to 2,700 severe COVID-19 cases, depending on model specification. Conclusion: The non-mandatory, age-specific recommendations helped control the COVID-19 pandemic in Sweden.

scholarly journals The influence of the dynamics and the level of maturity of the cortical functions as a prerequisite for the development of speech in children

2019 ◽  
Vol 147 (3-4) ◽  
pp. 199-204
Author(s):  
Maja Davidovic ◽  
Jadranka Otasevic ◽  
Nada Dobrota-Davidovic ◽  
Ivana Petronic ◽  
Dragomir Davidovic ◽  
...  
Keyword(s):  
Motor Control ◽  
Evoked Potentials ◽  
Physiological Changes ◽  
Articulation Disorder ◽  
Significant Difference ◽  
Cortical Responses ◽  
Quasi Experimental ◽  
Waveform Amplitude ◽  
And Control ◽  
The Impact

Introduction/Objective. The development of speech is the result of interaction of different systems of the cortex, which gradually acquires the ability of phonological presentation and motor control, in the presence of a series of physical and physiological changes in the morphology of the articulation system. The objective of the study was to examine the impact of laterality and cortical responses on the development of speech in children. Methods. Research is a quasi-experimental design with two groups. The sample covered 60 children from Belgrade, of both sexes, ages 5.5?7 years, divided into two groups, experimental (30) and control (30). We used the following instruments: test for assessing laterality and ascertaining evoked potentials. Results. On the visual lateralization subtest there was a statistically significant difference (?2 = 7.56, p < 0.05) between the observed groups. The visual evoked potentials on all measured parameters gave a statistically significant difference between the groups: waveform cortical responses ? left (?2 = 30.00, df = 1, p < 0.05); cortical responses ? right (?2 = 6.667, df = 1 , p < 0.05); waveform amplitude ? left (?2 = 13.469, df = 1, p < 0.05); amplitude ? right (?2 = 40.00, df = 1, p < 0.05), somatosensory potentials (?2 = 18.261, df = 1, p <0.05); waveform amplitude (?2 = 12.000, df = 1, p < 0.05); waveform latency (?2 = 5.455, df = 1, p < 0.05). Conclusion. Visual laterality, as well as visual and somatosensory cortical responses to stimuli is better in children without the present articulation disorder, which could be used for timely prevention planning.

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