Control Variables Research Articles

Spatial-Temporal Structure Features of Muscle Synergies During Profiling Elements Implementation in Rhythmic Gymnastics

The article presents an analysis of the muscle synergies involved in making ball throws in different directions and from different starting positions. The study involved 6 highly qualified athletes engaged in rhythmic gymnastics. Electromyograms of the superficial muscles of the upper extremities and trunk were recorded synchronously during the movements, as well as video capture of the movements of body segments. Synergy parameters were extracted from the recorded signals using factor analysis using the principal component method. It has been established that individuals who have mastered a complex motor skill can demonstrate similar motor control strategies. This is manifested in the structuring of intermuscular interaction in the form of two general modules, the degree of involvement of muscles in which is highly similar in the implementation of different motor tasks. The first muscle module implements active movement of the upper limb by jointly activating the muscles of the forearm, shoulder and upper shoulder girdle, and also provides stabilization of the position of the trunk by synchronizing the activity of the muscles of the back and abdomen. The second muscle module is specific and is mainly associated with high involvement in the synergy of the muscles of the upper shoulder girdle and forearm for the implementation of exercises performed without visual control, or from starting positions that limit the mobility of certain parts of the body. Thus, the solution to the problem of coordination of many elements of the motor system may consist not only in reducing the number of executive organs – muscles involved in control, but also in organizing control variables in the form of modules at the kinematic level and their stabilization through muscle synergies.

Interoception mediates the association between social support and sociability in patients with major depressive disorder.

Interoception dysfunction has an important impact on the onset and development of major depressive disorder (MDD). Social support serves as a protective factor against MDD, and sociability also plays a significant role in this condition. These interconnected constructs-social support and sociability-play pivotal roles in MDD. However, no research on the mechanisms underlying the associations between social support and sociability, particularly the potential role of interoception, have been reported. To investigate the mediating effect of interoception between social support and social ability and to explore the independent role of social support in sociability. The participants included 292 patients with MDD and 257 healthy controls (HCs). The patient health questionnaire 9, the multidimensional assessment of interoception awareness, version 2 (MAIA-2), the social support rating scale (SSRS), and the Texas social behavior inventory (TSBI) were used to assess depression, interoception, social support, and sociability, respectively. A mediation analysis model for the eight dimensions of interoception (noticing, not distracting, not worrying, attention regulation, emotional awareness, self-regulation, body listening, and trust), social support, and sociability were established to evaluate the mediating effects. A partial correlation analysis of eight dimensions of the MAIA-2, SSRS, and TSBI scores, with demographic data as control variables, revealed pairwise correlations between the SSRS score and both the MAIA-2 score and TSBI score. In the major depression (MD) group, the SSRS score had a positive direct effect on the TSBI score, while the scores for body listening, emotional awareness, self-regulation, and trust in the MAIA-2C had indirect effects on the TSBI score. In the HC group, the SSRS score had a positive direct effect on the TSBI score, and the scores for attention regulation, emotional awareness, self-regulation, and trust in the MAIA-2C had indirect effects on the TSBI score. The proportion of mediators in the MD group was lower than that in the HC group. Interoceptive awareness is a mediating factor in the association between social support and sociability in both HCs and depressed patients. Training in interoceptive awareness might not only help improve emotional regulation in depressed patients but also enhance their social skills and support networks.

An integrated approach for multi-objective differential algorithm based event constrained optimal power flow for power system resiliency enhancement

ABSTRACT Due to climatic changes, the probability of occurrence and the intensity of extreme weather events increase day by day which leads to power outages. The probability of failure events is calculated using Monte Carlo simulation technique which is used to identify the most frequent failure events. The least eigenvalues of the inverse reduced Jacobian matrix decide the sensitive buses for load shedding using V-Q sensitivity analysis. This work presents the multi-objective differential evolution (MODE) algorithm for solving resilient constrained optimal power flow (RCOPF) in a deregulated power system. The control variables namely the real power of generators in a base case and under event, generator bus voltage magnitude, the real and reactive power demand of the selected load buses, tap settings and capacitor bank ratings. This algorithm is validated in IEEE 30 bus test system and the Indian 62 bus utility test system to show the effectiveness in four different cases including tie lines and distributed generation.

ARE INTELLECTUAL CAPITAL AND ITS COMPONENTS AFFECTIVE ON FINANCIAL PERFORMANCE?

The factors that affect intellectual capital creation at firms and how these factors influence the financial performance of firms have been core questions of extant work in the channels of finance for many years. In this period, therefore, the efforts that firms make to increase their intellectual capital to create value and studies that examine the impact of the increased intellectual capital on the firm’s financial performance are notable. Thus, this study aims to explore the influence of intellectual capital and its components on the financial performance of the BIST Sustainability Index companies for the period between 2018:Q4-2024:Q1. A set of Intellectual Value Added Coefficient (VAIC) and its components Human Capital Efficiency (HCE), Structural Capital Efficiency (SCE), and Capital Employed Efficiency (CEE) are employed as indicators of intellectual capital. The financial performance is measured through Return on Assets (ROA) and Return on Capital Employed (ROCE). Control variables included in each model are Market to Book Value (MV/BV), Logarithm of Total Assets (SIZE), and Asset Turnover (ATR). The fixed effects regression results show that an increase in the intellectual capital of the companies listed in the BIST Sustainability Index has a positive effect on their financial performance.

Understanding human-obstacle interaction dynamics on staircases: Implications for emergency evacuation and fire safety in high-rise buildings

Interactions between system components, including human-obstacle, human-building, human-robot, and human-human, significantly impact public safety, system efficiency, and functionality. A deeper understanding of these systems is essential to enhance their resilience and effectiveness. Despite the significance of these interactions, empirical research is limited, particularly regarding behavioral mechanisms when interacting with obstacles on stairways. Our study examines the evacuation behavior of 90 evacuees on the staircase of a high-rise building under different temporary obstacle conditions to understand how key factors affect decision-making and motion behavior during stairway descent. The experiments considered obstacle shapes as control variables and analyzed evacuation time, inner and outer stair route choices, regional speed fluctuations, velocity-relative displacement, evacuation efficiency, and biomechanical analysis of occupants’ comfort. Results show that larger obstacle shapes, increased evacuation urgency time, and closer proximity to the wall lead to a higher proportion of the splitting to merging state before and after obstacle interaction. A strong inner stair route preference emerges in no-obstacle conditions, with significant mean speed differences in downward movements when encountering temporary obstacle. Three phases of average speed variations are observed: deceleration, acceleration, and continued deceleration for the outer route; and deceleration followed by uniform speed for the inner route. A method was developed to calculate regional speed fluctuation using average speeds from trajectories. Comfort analysis revealed that temporary obstacle on building stairways significantly impact safe evacuation. Overall, these findings enhance the understanding of crowd dynamics in high-rise building emergency evacuations, with implications for model development, architectural design, building operations, emergency preparedness, behavioral cognition, and fire safety.

Cultural Industry Agglomeration and Carbon Emission Performance: Empirical Analysis Based on 276 Cities in China

This study investigated the influence of cultural industry agglomeration on the energy carbon emission performance (CEP). Based on panel data from 276 cities in China, we used the Super-SBM model to measure the CEP. We then used the Tobit regression model to calculate the influence coefficient of cultural industry agglomeration and eight control variables on the CEP and analyzed the complex effects of cultural industry agglomeration on the CEP. The results showed that there is the phenomenon of “diseconomies of agglomeration” in cultural industry agglomeration, which cannot improve the CEP. For each unit of cultural industry agglomeration increase, the CEP decreases by 0.055; however, this phenomenon is not linear. Further research showed that the effects of cultural industry agglomeration showed a trend from good to inferior in the order of east, central, and west and did not improve with time. Finally, we used the panel quantile regression model and found that as the CEP levels rise, the negative impact of cultural industry agglomeration improves. Our research results show that strengthening the technical level to promote the upgrading of the cultural industry is the best way to achieve sustainable development. Governments at all levels should pay attention to the emission reduction potential of cultural industry agglomeration under high CEP levels and strengthen the benign agglomeration of the cultural industry.

Urbanization as a catalyst for structural transformation in developing countries: The mediating impact of foreign direct investment

This article analyzes the link between urbanization and the process of structural transformation (ST) in developing countries, taking into account the mediating role that FDI can play. We use secondary data from 2000 to 2023 to determine if FDI positively or negatively influences the ST process in these countries, thereby, altering urbanization patterns. By estimating the Generalized Method of Moments (GMM), the study explores the relationship between urbanization, the ST process, and the mediating role played by FDI. In addition, it takes into account control variables such as gross fixed capital formation (GFCF), gross domestic product per capita (GDPPC), and diversification of production structure (DPS) to analyze their effect on urbanization and, more specifically, on the ST process. The econometric results showed a negative correlation between FDI flows and urbanization, demonstrating that FDI could hinder the success of the ST process in developing countries. On the contrary, econometric results showed that the control variables, GFCF, GDPPC, and DPS, positively influence urbanization in developing countries, indicating that these variables are more conducive to a successful ST process than FDI. Based on the econometric results, policymakers in developing countries are called upon to strengthen urbanization in these countries, by encouraging local investment and the diversification and sophistication of production and export structures, rather than relying solely on FDI. Over the period studied, FDI has not contributed as expected to advancing the urbanization process, a crucial element in the ST process in developing countries.

Never bring a knife to a gunfight? Lethality of weapon use in Dutch homicides

Firearm violence is a serious issue in Europe, yet the validity of existing theoretical approaches to weapon use in violent encounters have not been explicitly tested in the European context. This study tested existing hypotheses on weapon use and lethality – the Adversary Effects Hypothesis, the Physical Strength Hypothesis, and the Social Distance Hypothesis – using homicide data from the Netherlands, where detailed data on weapon use in homicide are available. Based on these hypotheses, we expected victim characteristics and the social distance between the victim and perpetrator to affect the modus operandi. However, our results do not align with these expectations when situational control variables are included. We conclude that existing studies on weapon lethality have a limited generalizability due to their assumption of free weapon choice. This is only met in contexts in which legal availability of firearms is high, which is not the case in the Netherlands. In addition, the hypotheses focus too narrowly on victim characteristics, without accounting for the situational factors influencing violent encounters. Based on these insights, we provide suggestions for theoretical and empirical improvements on firearm violence research.

Fundamental VS Makro Ekonomi on Stock Price : Indonesian Stock Exchange (IDX)

Geopolitical tensions especially those occurring in the Middle East, have significantly impacted the world economy. This impact was also felt by the Indonesian state, which impacted company share prices which experienced a decline due to geopolitical tensions, including the banking sector. Apart from geopolitical tensions, several other factors, such as the company's fundamental factors, also influenced the decline in share prices. Fundamental factors play an important role in determining a company's share price. These factors refer to various elements and variables that reflect the company's financial condition, operations, and prospects. So quite a few investors use fundamental analysis to assess whether current share prices reflect the company's true intrinsic value. This study seeks to reassess the elements affecting banking share prices by incorporating macroeconomic control variables related to these concerns to enhance the robustness of the findings. Utilizing a quantitative approach through panel data regression, the research focuses on banks listed on the Indonesia Stock Exchange from 2019 to 2023, with a sample of 16 companies meeting the selection criteria. The results reveal that Debt Equity Ratio (DER), Return On Assets (ROA), Return On Equity (ROE), GDP, inflation, and exchange rates collectively have a positive and significant impact on stock prices. However, when analyzed individually, only ROE and exchange rates show a significant effect, while DER, ROA, GDP, and inflation do not.

Climate emotions, thoughts, and plans among US adolescents and young adults: a cross-sectional descriptive survey and analysis by political party identification and self-reported exposure to severe weather events

Climate change has adverse effects on youth mental health and wellbeing, but limited large-scale data exist globally or in the USA. Understanding the patterns and consequences of climate-related distress among US youth can inform necessary responses at the individual, community, and policy level. A cross-sectional descriptive online survey was done of US youth aged 16-25 years from all 50 states and Washington, DC, between July 20 and Nov 7, 2023, via the Cint digital survey marketplace. The survey assessed: climate-related emotions and thoughts, including indicators of mental health; relational aspects of climate-related emotions; beliefs about who or what has responsibility for causing and responding to climate change; desired and planned actions in response to climate change; and emotions and thoughts about the US Government response to climate change. Respondents were asked whether they had been affected by various severe weather events linked to climate change and for their political party identification. Sample percentages were weighted according to 2022 US census age, sex, and race estimates. To test the effects of political party identification and self-reported exposure to severe weather events on climate-related thoughts and beliefs we used linear and logistic regression models, which included terms for political party identification, the number of self-reported severe weather event types in respondents' area of residence in the past year, and demographic control variables. We evaluated survey responses from 15 793 individuals (weighted proportions: 80·5% aged 18-25 years and 19·5% aged 16-17 years; 48·8% female and 51·2% male). Overall, 85·0% of respondents endorsed being at least moderately worried, and 57·9% very or extremely worried, about climate change and its impacts on people and the planet. 42·8% indicated an impact of climate change on self-reported mental health, and 38·3% indicated that their feelings about climate change negatively affect their daily life. Respondents reported negative thoughts about the future due to climate change and actions planned in response, including being likely to vote for political candidates who support aggressive climate policy (72·8%). In regression models, self-reported exposure to more types of severe weather events was significantly associated with stronger endorsement of climate-related distress and desire and plans for action. Political party identification as Democrat or as Independent or Other (vs Republican) was also significantly associated with stronger endorsement of distress and desire and plans for action, although a majority of self-identified Republicans reported at least moderate distress. For all survey outcomes assessed in the models, the effect of experiencing more types of severe weather events did not significantly differ by political party identification. Climate change is causing widespread distress among US youth and affecting their beliefs and plans for the future. These effects may intensify, across the political spectrum, as exposure to climate-related severe weather events increases. Avaaz Foundation.

Clinic personnel attitudes and baseline implementation outcomes of a lupus decision aid

ABSTRACT To examine the association between clinical personnel’s general attitudes towards new interventions and implementation outcomes related to an evidence-based individualized, culturally tailored, computerized decision aid (DA) for the management of lupus. To assess attitudes, the validated Evidence-Based Practice Attitudes Scale (EBPAS) survey was emailed to personnel in 15 rheumatology clinics across the U.S. The survey also included questions related to three validated implementation outcomes: lupus DA acceptability, appropriateness and feasibility. The baseline round of the survey was fielded from August 2019 to January 2020 and yielded a 56.8% response rate (n = 76 respondents). We also collected organizational characteristics from each clinic and personnel-level control variables. Overall, respondents reported modest levels of lupus DA acceptability, appropriateness and feasibility (3.54, 3.45 and 3.40, respectively, on a scale of 1–5). Multilevel regression analyses demonstrated statistically significant positive relationships between a respondent’s openness to new practices/interventions and perceived lupus DA acceptability (β = 0.31, p < .01) and feasibility (β = 0.28, p < .05). Divergence (a respondent’s perceived difference between current and new practices) was not associated with clinic personnel perceptions of the DA. These findings suggest that understanding clinic personnel general attitudes toward new interventions is an important precursor to implementing evidence-based practices and may provide important diagnostic information about places to intervene in preparation for implementation and improving shared decision-making with patients.

Income inequality: The effects of public education expenditure and information and communications technology in sub-Saharan Africa

Background: As nations globally strive to meet the United Nations Sustainable Development Goal (SDG) 10, which underscores the reduction of inequality, there is an increasing need to harness the power of education and information and communications technology (ICT) to achieve this aim. Therefore, this study is motivated by this rationale.Aim: The synergistic effect of government spending on education and ICT on income inequality in sub-Saharan Africa (SSA) in the long run.Setting: Panel data for 30 SSA countries from 1990 to 2022 are used.Method: This research used the Fully Modified Ordinary Least Square (FMOLS) technique, which provides long-run estimates, to achieve the aim of the article.Results: The FMOLS results reveal that public education expenditure increases income inequality while its squared expenditure reduces it in the long run. However, over time, ICT diminishes inequality. Notably, the combined effect of public education spending and ICT strengthens the effect of public education expenditure on income inequality in SSA in the long term.Conclusion: In summary, with the incorporation of additional control variables in the analyses, it suggests that SSA’s governments, along with policymakers, have the opportunity to achieve income inequality reduction by strategically making use of public education spending and ICT.Contribution: This article adds significant value to the literature by demonstrating the effect of public education spending and ICT on income inequality in SSA (characterised by higher level of income inequality). To mitigate concerns regarding endogeneity, this article uses FMOLS.

Emotional Marketing, Customer Retention, and Brand Loyalty in Vietnam’s Retail Sector: Unveiling the Moderating Impact of Digital Innovativeness

This study investigates the relationship between emotional marketing, brand loyalty, and customer retention in Vietnam’s retail sector, while examining the moderating role of digital innovativeness, comprising personal and brand innovativeness. A conceptual model is developed and empirically tested using a sample of 533 Vietnamese retail consumers. The model incorporates emotional marketing as the main predictor, brand loyalty as the mediator, customer retention as the outcome, and digital innovativeness as the moderator. Relevant determinants of brand loyalty, such as customer satisfaction, perceived value, emotional attachment, and brand identity, are included as control variables. The data is analyzed using structural equation modeling. The results reveal that emotional marketing has a significant positive impact on brand loyalty, which in turn leads to higher customer retention. Digital innovativeness is found to positively moderate the relationship between emotional marketing and brand loyalty. The study highlights the importance of leveraging emotional marketing strategies and fostering digital innovativeness to build strong emotional connections, brand loyalty, and long-term customer retention in the Vietnamese retail market. This research contributes to the understanding of emotional marketing’s impact on brand loyalty and customer retention in the context of Vietnam’s retail sector, while uniquely exploring the moderating effect of digital innovativeness. The findings provide valuable insights for retailers seeking to optimize their marketing strategies and adapt to the evolving needs of Vietnamese consumers in the digital age.

Do gender diversity and foreign investor affect sustainability disclosure

AbstractWe examine the effect of female board members and foreign institutional investors on corporate social responsibility (sustainability) disclosure in Indonesian listed firms from 2015 to 2017. Our final sample comprised 1192 firm‐year observations. We apply ordinary least squares pool regression to estimate the associations and address the endogeneity problem using the two‐stage least squares model, generalized method of moments, and lagged variables. While previous studies have focused on the impact of female board members and foreign institutional investors on financial outcomes, we extend the literature by investigating the association between both female board members and foreign investors and sustainable disclosure in Indonesia, where the participation of women is nominal, especially at the top management level, and the level of foreign ownership is high. Our findings propose a proportion of women as board members for listed firms and promote attractive policies to increase the number of foreign investors investing in Indonesia. It also contributes to conflicting results regarding the relationship between corporate governance and corporate social responsibility (CSR) commitment. Our results were robust after testing for endogeneity and adding more control variables. Overall, the findings have practical implications for policymakers and investors regarding corporate disclosure and governance in Indonesia.

Climate change and economic growth: Evidence for European countries

AbstractClimate change may affect economies and the welfare of people around the world. To design appropriate policy responses, the economic effects of climate change should be known. One strand in the literature empirically estimates the growth effects of climatic variations. However, those studies often neglect economic variables that have proven to be robust in explaining economic growth. Further, often they fail to check for the robustness of their results. The main aim of this study is to detect whether there exists a statistically significant robust relation between climate change and economic growth by estimating different model specifications. To do so panel estimation techniques for 24 European economies for the period from 2002 to 2019 are applied whereby panel fixed effects estimations and dynamic Generalized Methods of Moments estimations are resorted to. No statistically significant robust relationship between the temperature change and economic growth is found just as for precipitation that does not exert a significant effect on growth. As regards the institutional and macroeconomic control variables the rule of law, the fiscal variable, and the output gap are statistically significant and robust. It is argued that far‐reaching policy measures, such as the net zero goal of the European Union, should be given only based on robust results. Otherwise, economic policy may turn out to be inadequate and can lead to welfare losses. Hence, the conclusion is that the net zero goal of the European Green Deal is to be seen skeptical.

The Effect Of Board Capital On The Efficiency Of Indonesian Commercial Banks In 2020-2022

This study aims to examine whether Board Capital factors have an effect on the efficiency of state-owned and private commercial banks in Indonesia. This study uses secondary data from annual reports and LinkedIn for 48 commercial banks in Indonesia for the period 2020-2022. The results of the study show that Education Capital does not have an effect on bank efficiency, Experience Capital has a negative effect, and Networking Capital has a positive effect. The significant control variables are NIM, Bank size, Bank age, and Pandemic year. Board of directors' networking becomes an important factor in improving bank efficiency in Indonesia.

A Retrospective Observational Study Examining Physical Activity Among Adults in the United States With Angina or Coronary Heart Disease.

Coronary heart disease (CHD) involves inadequate blood supply to the myocardium by the coronary arteries due to the formation of atherosclerotic plaque in the vessel lumen. It has a complex etiopathogenesis. Physical activity (PA) and exercise lead to vascular remodeling and improved endothelial function, which, in turn, improves the arterial blood supply to the myocardium. The study aims to determine the prevalence of self-reported PA among CHD patients in the United States based on demographic, socioeconomic, and healthcare access variables for the year 2021. The data for the study on CHD were extracted using the Behavioral Risk Factor Surveillance System (BRFSS) Web-Enabled Analysis Tool database of the U.S. The control variables used broadly include demographics, socioeconomic, and healthcare access. In 2021, 433,615 people in the USA participated in the BRFSS study. Among them, 22,819 self-identified as having angina or CHD. In the past month, 62.2% of participants with the disease were involved in PA, and 37.8% were not. Among participants without angina or CHD, 76.5% were involved, and 23.5% were not involved in PA in the past month. This study highlights the need for specific interventions to overcome obstacles preventing PA among CHD patients.

The Nexus Between Corporate Governance, CSR, and Firm Value: Tax Avoidance as an Intervening Variable

This research investigates the role of tax avoidance in the relationship between corporate governance, firm value, and corporate social responsibility. The research design is explanatory research, through hypothesis testing. 175 manufacturing companies were observed from 2017 to 2021, with a sample size of 875. A panel regression and leverage acted as a control variable using SPSS software, after conducting models and robustness tests. The findings show the influence of tax avoidance on institutional ownership and economic corporate social responsibility (CSR). Tax avoidance partially mediates the relationship between institutional ownership and firm value, and fully mediates between economic CSR and firm value. The implication for academics and practitioners is that enabling corporate governance requires institutional owners to supervise the determination of company managerial policies. Additionally, the economic CSR program can reduce tax avoidance and is responded to positively by investors. The limitations of the research are that for the constant value to be significant, additional variables should be added to the model. Further research could include adding company performance, gender, and intellectual capital variables. Keywords: corporate governance, corporate responsibility, tax avoidance, leverage, firm value

Health outcome convergence and the roles of public health financing and governance in Africa.

Progress in health outcomes across Africa has been uneven, marked by significant disparities among countries, which not only challenges the global health security but impede progress towards achieving the United Nations' Sustainable Development Goals 3 and 10 (SDG 3 and SDG 10) and Universal Health Coverage (UHC). This paper examines the progress of African countries in reducing intra-country health outcome disparities between 2000 and 2019. In other words, the paper investigates the convergence hypothesis in health outcome using a panel data from 40 African countries. Data were sourced from the World Development Indicators, the World Governance Indicators, and the World Health Organization database. Employing a non-linear dynamic factor model, the study focused on three health outcomes: infant mortality rate, under-5 mortality rate, and life expectancy at birth. The findings indicate that while the hypothesis of convergence is not supported for the selected countries, evidence of convergence clubs is observed for the three health outcome variables. The paper further examine the factors contributing to club formation by using the marginal effects of the ordered logit regression model. The findings indicate that the overall impact of the control variables aligns with existing research. Moreover, governance quality and domestic government health expenditure emerge as significant determinants influencing the probability of membership in specific clubs for the child mortality rate models. In the life expectancy model, governance quality significantly drives club formation. The results suggest that there is a need for common health policies for the different convergence clubs, while country-specific policies should be implemented for the divergent countries. For instance, policies and strategies promoting health prioritization in national budget allocation and reallocation should be encouraged within each final club. Efforts to promote good governance policies by emphasizing anti-corruption measures and government effectiveness should also be encouraged. Moreover, there is a need to implement regional monitoring mechanisms to ensure progress in meeting health commitments, while prioritizing urbanization plans in countries with poorer health outcomes to enhance sanitation access.

Improved Methods for Vaccine Effectiveness Studies.

Evaluating the impact of public health investments in vaccination programs is crucial for ensuring their efficiency and effectiveness. Vaccine effectiveness (VE) studies, such as those using the test-negative design (TND), are commonly used to confirm the impact of vaccines and to guide future improvements. The TND, favored for its simplicity and cost efficiency, mitigates biases common in other epidemiological study designs. However, its validity can be compromised by inconsistent symptom definitions and retrospective data application. Here we summarize recent findings that highlight the need to address correlated vaccination behaviors when estimating VE, that suggest using negative control variables to reduce confounding, and that recommend accounting for prior infection history in VE studies to improve accuracy and reliability. These insights are important for refining VE estimation methods.