Fixed-effects Model Research Articles

Double-edged sword effect of digital economy on FDI: evidence from Chinese cities

ABSTRACT Amid increasing global uncertainty, scholars are devoting increasing attention to the impact of the digital economy (DE) on foreign direct investment (FDI). However, previous studies have neglected the staged nature of DE development. Adopting a stage-based perspective, using panel data for 284 cities from 2011 to 2022, and employing a two-way fixed-effects model, this study investigates the U-shaped relationship between DE and FDI. By combining traditional and emerging FDI motives, this study further explores moderating mechanisms. The findings indicate that the impact of DE on FDI follows a U-shaped curve. In the early stage of DE, market maturity mitigates the negative relationship between DE and FDI, while digital infrastructure exacerbates it. In the mature stage, market maturity weakens the positive relationship between DE and FDI, whereas digital infrastructure and knowledge technology strengthen it. An unexpected result is that higher wage levels deter FDI in the early stage of DE but promote FDI once DE is mature. The results imply that, in the early stage of DE, policy support should prioritise market maturity and labour-related policies, whereas, in the mature stage, it should shift towards digital infrastructure and knowledge technology.

Effects of Environmental Unsustainability on Income Inequality: A Panel Data Analysis

The main goal of this research is to empirically examine how environmental unsustainability influences income disparity. Utilizing globally aggregated data and panel data analysis methods, the relationship between environmental indicators such as carbon emissions, natural resource depletion, deforestation, and climate change and the Gini coefficient is examined. When the analyses are performed individually for developed and developing nations, the results indicate that environmental degradation intensifies income inequality to a greater extent in developing countries compared to developed ones.. Based on the results obtained through the fixed effects model and the panel ARDL approach, it is determined that environmental degradation has a statistically significant and long-term exacerbating effect on income inequality. Granger causality tests indicate that environmental indicators have a unidirectional impact on income distribution inequity. However, the literature review suggests that this relationship is often examined as bidirectional. The findings of this research highlight the necessity of evaluating environmental and social policies in an integrated manner. In light of these results, it is recommended that environmental protection policies be shaped based on principles of fair and inclusive development to prevent the deepening of social inequalities.

Beneficial Effect of Platelet-Rich Fibrin as an Adjunct to Nonsurgical Therapy After Subgingival Professional Mechanical Plaque Removal for Periodontitis: A Systematic Review and Meta-Analysis

Background and Objectives: Periodontitis is an inflammatory disease that compromises the supporting structures of the teeth, leading to irreversible tissue damage and tooth loss. While subgingival professional mechanical plaque removal (PMPR) remains the gold standard treatment, there is increasing interest in adjunctive therapies. Platelet-rich fibrin (PRF) has gained attention as a promising biomaterial to enhance periodontal healing and regeneration. This study aimed to evaluate the clinical and immunological effectiveness of PRF as an adjunct to PMPR. Materials and Methods: Clinical studies published between January 2019 and August 2024 were included from the ProQuest, PubMed, PMC, ScienceDirect, Scopus, and EBSCO databases. Seven studies met the inclusion criteria, focusing on adults with periodontitis treated with PRF + PMPR compared to PMPR alone. Primary outcomes included changes in clinical and immunological parameters. Risk of bias was assessed using the Cochrane ROB2 tool. Meta-analysis was conducted using both fixed-effect and random-effects models, depending on heterogeneity. Results: The meta-analysis demonstrated significant improvements in clinical outcomes in the PRF + PMPR group, with reductions in probing pocket depth (SMD: −1.43 mm; 95% CI: −2.05 to −0.81; p < 0.00001), clinical attachment level (SMD: −1.34 mm; 95% CI: −1.95 to −0.73; p < 0.0001), bleeding on probing (SMD: −0.75 mm; 95% CI: −1.11 to −0.39; p < 0.00001), gingival recession (SMD: −0.79 mm; 95% CI: −1.33 to −0.25; p = 0.004), and gingival index (SMD: −0.82 mm; 95% CI: −1.37 to −0.28; p = 0.003). Favorable trends were also observed in IL-10, TGF-β, VEGF, PDGF-BB, periostin, and type I collagen levels. Conclusions: PRF enhances clinical and immunological outcomes and supports periodontal tissue stability when used as an adjunct to non-surgical therapy.

Does the demonstration area policy promote the documentary services of public libraries?

PurposeThe purpose of this study is to examine the impact of the national public cultural service system demonstration area policy on the documentary service capacity of public libraries, the differences in the effectiveness of the policy in different regions and the policy superimposition effect between the demonstration projects and the demonstration area policy.Design/methodology/approachThe study adopts the difference-in-difference (DID) method, which approximates a natural experiment, to evaluate the impact of the policy by comparatively analyzing the changes in the documentary service capacity of public libraries of the experimental and control groups.FindingsThe study reveals that the demonstration area policy can enhance the documentary service capacity of public libraries. From the perspective of urban location, it is found that there are differences in the effectiveness of the demonstration area policy on cities in different regions. The impact on cities in the eastern region is significantly higher than that on cities in the central and western regions. From the perspective of policy superimposition, it is found the demonstration projects do not have a policy superimposition effect on the demonstration area policy.Originality/valueThe study adopts a two-way fixed-effects model for DID, in addition to traditional variables, adding the individual fixed-effect, the time fixed-effect and other control variables to reduce the estimated bias caused by the omitted variables and unobservable characteristics, as well as time trends. The findings will provide a reference for governmental decision-making.

The impact of music industry digitalisation on population well-being: Empirical evidence from China.

With the profound transformations brought about by digital technology in the global economy and social operations, digital music has emerged as a vital medium for meeting residents' cultural needs, playing a significant role in promoting cultural dissemination and catering to personalized cultural demands. Previous research has mainly focused on the commodity attributes, symbolic functions, and instrumental value of digital music at the micro level, while studies examining the potential impact of music industry digitalization on residents' well-being remain relatively scarce. Addressing this gap, this study empirically investigates the impact and underlying mechanisms of music industry digitalization on residents' happiness by constructing a fixed-effects model based on data from the 2022 China Family Panel Studies (CFPS). The results reveal that: (1) the digitalization of the music industry significantly enhances residents' subjective well-being; (2) digitalization promotes happiness primarily by boosting social participation, increasing social trust, and improving mental health; and (3) compared to residents with higher Internet access frequency, higher educational attainment, and higher economic status, the positive effects of music industry digitalization on happiness are more pronounced among those with lower Internet access frequency, lower education levels, and lower economic status. This study provides new empirical evidence for understanding the social effects of digital cultural consumption and offers important insights for optimizing cultural policies and improving residents' quality of life.

Vitamin B12 and Folate in Adherent and Non-Adherent Individuals with Phenylketonuria: A Cross-Sectional Study, Systematic Review, and Meta-Analysis

Background/Objectives: The impact of dietary adherence and regular formula intake on the vitamin levels in individuals with phenylketonuria (PKU) remains unclear. This study aimed to assess the influence of both adherence to dietary management and regular formula intake on the vitamin B12 and folate levels in individuals with PKU. Methods: This cross-sectional multicentre study included 63 patients with PKU aged 12–41 years. The participants were classified as adherent or non-adherent based on their mean plasma phenylalanine levels or as regular or irregular formula consumers. The participants’ vitamin B12 and folate levels were compared across these groups. In addition, a systematic search of PubMed, Web of Science, Scopus, and Cochrane Library identified 11,631 studies comparing vitamin B12 and folate levels between adherent vs. non-adherent patients and regular vs. irregular formula intake groups, of which eight met the inclusion criteria. Analyses were conducted using random-effects and fixed-effects models and effect sizes were expressed as standardised mean differences (SMDs). Results: This cross-sectional study showed significantly higher vitamin B12 and folate levels in adherent vs. non-adherent individuals (767.6 ± 264.5 vs. 524.7 ± 216.4 pg/mL; 13.44 ± 1.96 vs. 10.62 ± 3.36 ng/mL, both p < 0.001) and in regular vs. irregular formula consumers (746.7 ± 228.4 vs. 527.4 ± 281.9 pg/mL; 13.32 ± 2.25 vs. 10.48 ± 3.23 ng/mL, p < 0.0001 and p < 0.001 respectively). The meta-analysis found no significant differences between the adherent and non-adherent groups, which were defined based on their phenylalanine levels, but showed higher vitamin B12 levels (fixed-effects model, SMD: 1.080, 95% CI: 0.754, 1.405, p < 0.0001) and a near-significant trend toward higher folate levels (random-effects model, SMD: 0.729, 95% CI: −0.032, 1.490, p = 0.061) in regular formula consumers. Conclusions: Regular formula intake is a key determinant of vitamin B12 in patients with PKU. These findings highlight the importance of consistent formula use in dietary management and warrant further research.

Long-term exposure to dust in fine particulate matter and post-stroke functional impairment-Findings from the China National Stroke Screening Surveys.

Long-term exposure to dust in fine particulate matter and post-stroke functional impairment-Findings from the China National Stroke Screening Surveys.

The Effect of Immunotherapy on Natural Killer Cells Level/Activity in Recurrent Pregnancy Loss (RPL) Patients: A Systematic Review and Meta-Analysis.

Some studies have demonstrated that high level of natural killer (NK) cells or NK cytotoxicity was associated with unexplained recurrent pregnancy loss (RPL) and can serve as predictive indicator for subsequent miscarriage in RPL patients. This suggests that reducing the level or activity of NK cells may represent a potential therapeutic strategy. However, there remains controversy regarding the efficacy of current immunotherapies employed in clinical practice for modulating the number and function of NK cells in RPL patients. Consequently, this study aimed to systematically review and assess the impact of various immunotherapies on NK cells in RPL patients, as well as the effectiveness of improving pregnancy outcomes in RPL patients with abnormal NK cells level/activity. This systematic review and meta-analysis was conducted following the PRISMA guidelines and recommendations of the Cochrane Collaboration. A comprehensive search was conducted on PubMed, Web of Science, EMBASE, and the Cochrane Library to identify relevant studies on immunotherapy in patients with RPL up to September 2023. Meta-analyses were used to assess the impact of immunotherapy on NK cells level and activity in RPL patients. Narrative synthesis was conducted to evaluate the effect of immunotherapies on pregnancy outcomes in RPL patients with abnormal NK cells level/activity. Risk-of-bias was assessed using ROBINS-I. A random-effects model or a fixed-effects model was selected according to the heterogeneity test, and standard mean differences (SMDs), risk ratio (RR) and 95% confidence interval (95% CI) were calculated. A total of 17 studies were included in this analysis. The meta-analysis revealed that in the general population of patients with RPL, intravenous immunoglobulin (IVIg) led to a reduction in peripheral natural killer (pNK) cells level (SMD: -0.85, 95% CI: -1.41 to -0.28), lymphocyte immunotherapy (LIT) decreased pNK cell activity, and intralipid reduced both pNK cells level (SMD: -0.32, 95% CI: -0.64 to -0.01) and activity (SMD: -0.74, 95% CI: -1.06 to -0.42). The narrative synthesis illustrated the regulatory impact of immunotherapy on diverse immune cells and cytokines in RPL patients. Furthermore, IVIg and intralipid therapy could potentially enhance live birth rates in RPL patients specifically characterized by elevated pNK cells level. For RPL patients with elevated uterine NK (uNK) levels, cyclosporin A may ameliorate pregnancy outcomes, while prednisolone does not appear to have the same effect. Nevertheless, these findings should be approached with caution given the current insufficiency of evidence. Limited evidence indicated that IVIg, LIT, and intralipid reduce pNK cells level/activity in RPL patients. RPL patients with elevated NK levels may be benefit from immunotherapy, but not all immunotherapies were effective. However, interpretation of these results with caution is strongly advised due to the limited number of high-quality evidence.

Surgical Nerve Decompression at Lower Extremity for Diabetic Neuropathy: A Systematic Review and Meta-Analysis of Time-Dependent Pain, Sensory Recovery, Amputation, Ulcer Recurrence, and Balance.

Surgical Nerve Decompression at Lower Extremity for Diabetic Neuropathy: A Systematic Review and Meta-Analysis of Time-Dependent Pain, Sensory Recovery, Amputation, Ulcer Recurrence, and Balance.

Does fiscal decentralization foster renewable electricity generation? A panel data study of OECD countries

As the global community intensifies efforts to transition toward sustainable energy systems, the role of institutional and fiscal arrangements in fostering renewable energy has gained increasing attention. This study aims to assess whether fiscal decentralization contributes to the expansion of renewable electricity generation in OECD countries by analyzing panel data and identifying the direction and significance of this relationship. Utilizing a panel dataset of 34 countries spanning 2000–2023, the analysis employs a fixed-effects regression model with Driscoll-Kraay standard errors. It includes a one-year lag of fiscal variables to ensure robustness. The findings reveal a statistically significant but modest negative relationship between the share of subnational revenues in GDP and the share of renewables in electricity generation, suggesting that greater fiscal decentralization may not automatically incentivize renewable energy adoption. More specifically, the fixed-effects model corrected for heteroskedasticity and autocorrelation indicates that the coefficient for lagged subnational revenue (as a percentage of GDP) is negative and marginally significant (p ≈ 0.057), hinting at a potential delayed inhibitory effect. Additionally, country-level fixed effects demonstrate substantial heterogeneity, with nations like Iceland, Norway, and Canada showing systematically higher renewable electricity shares, regardless of fiscal structure. These results underscore the importance of complementary institutional frameworks and national coordination mechanisms to ensure that decentralization effectively supports climate policy goals. AcknowledgmentThis study was carried out within the framework of a research grant awarded by the Swiss National Science Foundation (grant no. IZURZ1_224119/1) and funded by the European Union grant “NextGenerationEU through the Recovery and Resilience Plan for Slovakia” (No. 09I03-03-V01-00130) and project VEGA – 1/0392/23 “Changes in the approach to the creation of companies’ distribution management concepts influenced by the effects of social and economic crises caused by the global pandemic and increased security risks”.

E-Health and M-Health in Obesity Management: A Systematic Review and Meta-Analysis of RCTs

Background: Obesity in adults is a growing health concern. The principal interventions used in obesity management are lifestyle-change interventions such as diet, exercise, and behavioral therapy. Although they are effective, current treatment options have not succeeded in halting the global rise in the prevalence of obesity or achieving sustained long-term weight maintenance at the population level. E-health and m-health are both integral components of digital health that focus on the use of technology to improve healthcare delivery and outcomes. The use of eHealth/mHealth might improve the management of some of these treatments. Several digital health interventions to manage obesity are currently in clinical trials. Objective: The aim of our systematic review is to evaluate whether digital health interventions (e-Health and m-Health) have effects on changes in anthropometric measures, such as weight, BMI, and waist circumference and behaviors such as energy intake, eating behaviors, and physical activity. Methods: A search was conducted for randomized controlled trials (RCTs) conducted through 4 October 2024 through three databases (Medline, Web of Science, and Scopus). Studies were included if they evaluated digital health interventions (e-Health and m-Health) compared to control groups in overweight or obese adults (BMI ≥ 25 kg/m2) and reported anthropometric or lifestyle behavioral outcomes. Study quality was assessed using the Cochrane Risk of Bias Tool (RoB 2). Meta-analyses were performed using random-effects or fixed-effects models as appropriate, with statistical significance set at p < 0.05. Results: Twenty-two RCTs involving diverse populations (obese adults, overweight individuals, postpartum women, patients with eating disorders) were included. Digital interventions included biofeedback devices, smartphone apps, e-coaching systems, web-based interventions, and mixed approaches. Only waist circumference showed a statistically significant reduction (WMD = −1.77 cm; 95% CI: −3.10 to −0.44; p = 0.009). No significant effects were observed for BMI (WMD = −0.43 kg/m2; p = 0.247), body weight (WMD = 0.42 kg; p = 0.341), or lifestyle behaviors, including physical activity (SMD = −0.01; p = 0.939) and eating behavior (SMD = −0.13; p = 0.341). Body-fat percentage showed a borderline-significant trend toward reduction (WMD = −0.79%; p = 0.068). High heterogeneity was observed across most outcomes (I2 > 80%), indicating substantial variability between studies. Quality assessment revealed predominant judgments of “Some Concerns” and “High Risk” across the evaluated domains. Conclusions: Digital health interventions produce modest but significant benefits on waist circumference in overweight and obese adults, without significant effects on other anthropometric or behavioral parameters. The high heterogeneity observed underscores the need for more personalized approaches and future research focused on identifying the most effective components of digital interventions. Digital health interventions should be positioned as valuable adjuncts to, rather than replacements for, established obesity treatments. Their integration within comprehensive care models may enhance traditional interventions through continuous monitoring, real-time feedback, and improved accessibility, but interventions with proven efficacy such as behavioral counseling and clinical oversight should be maintained.

Validity and feasibility of the oxford mental illness suicide tool (OxMIS): A mini-review and meta-analysis.

Validity and feasibility of the oxford mental illness suicide tool (OxMIS): A mini-review and meta-analysis.

Risk Factors for Cage Subsidence After Transforaminal Lumbar Interbody Fusion: A Systematic Review and Meta-Analysis.

A systematic review and meta-analysis. Cage subsidence (CS) is a common complication following transforaminal lumbar interbody fusion (TLIF) surgery. This study aimed to identify and analyze risk factors associated with CS following TLIF. A comprehensive search was conducted across PubMed, Scopus, Embase, and Google Scholar for studies published up to March 31, 2024. Pooled odds ratios (OR), standardized mean differences (SMD), and 95% CI were calculated for each identified risk factor. Interstudy heterogeneity was evaluated using the I² statistic, and either a random-effects or fixed-effects model was applied as appropriate. Publication bias was assessed through funnel plots. Nine studies, comprising data on 1403 patients who had undergone TLIF, were included in the final analysis. Significant risk factors for CS included age (SMD=0.27; 95% CI: 0.12-0.41) and bony endplate injury (OR=7.52; 95% CI: 2.08-27.17). However, no significant associations were found with other potential risk factors, such as cage height, body mass index (BMI), bone mineral density, smoking status, diabetes, sex, center point ratio (CPR), disc height (preprocedure and postprocedure), or surgery location. This meta-analysis identified older age and injury to the bony endplate as significant risk factors for CS after TLIF. These findings may help inform clinical decision-making and guide risk stratification in patients considering TLIF.

The green fog: the negative fallout of greenwashing on corporate reputation

Purpose This study aims to investigate how corporate greenwashing behavior undermines corporate reputation through the lens of information disclosure quality, with a focus on heterogeneous effects across ownership types, lifecycle stages and regional markets. Design/methodology/approach Using empirical data from listed companies on the main boards of the Shanghai and Shenzhen A-share markets, the study uses a fixed-effects regression model to analyze the nexus between greenwashing and corporate reputation. To address endogeneity concerns, instrumental variable approaches and propensity score matching methods are adopted. Mechanism analysis further examines the moderating role of information disclosure quality. Findings The results indicate that greenwashing behavior negatively influences corporate reputation. Furthermore, the mechanism test reveals that the negative impact is weakened as the quality of information disclosure improves. Additionally, the study reveals that the impact of greenwashing behavior on corporate reputation is more pronounced in state-owned enterprises, enterprises in the maturity stage and enterprises in the eastern regions. Originality/value The study challenges the linear assumption of ESG disclosure on reputation by revealing greenwashing’s “masking effect” on corporate reputation, thereby enriching the environmental, social and governance (ESG) paradox theory. Furthermore, the study integrates institutional heterogeneity and spatial economic factors into the greenwashing–reputation framework, offering contextualized insights for emerging markets. In addition, the paper offers firms practical advice on avoiding greenwashing and managing reputation. It also proposes strategies for regulators to enhance disclosure and conduct targeted supervision.

A simple and computationally trivial estimator for grouped fixed effects models

A simple and computationally trivial estimator for grouped fixed effects models

The effects of digitalization on the quality of marine economic development: evidence from a micro-level perspective

Digitalization is transforming the marine economy at an accelerating pace, yet its effects on the Quality of Marine Economic Development (QMED) and the pathways driving these changes are underexplored. This study investigates these dynamics using an unbalanced panel of 168 A-share listed marine firms in China over the period 2003–2023. We apply a two-way fixed effects model to estimate the effect of digitalization on QMED and explore its mechanisms, complemented by heterogeneity analyses across firm sizes, industry types, government attention, and human capital levels. The results show that digitalization improves QMED, with a 0.01 rise in the digitalization index—about one-fifth of its mean—lifting Total Factor Productivity (TFP) of marine firms by roughly 0.599, or 6.85% of the average TFP. Digitalization boosts QMED by enhancing firms’ resource allocation efficiency and spurring technological innovation. Larger firms benefit more than smaller ones, while labor-intensive industries outpace capital-intensive ones in QMED gains. Higher human capital levels weaken digitalization’s positive effect on QMED. These findings suggest practical strategies for practitioners, such as adopting cost-effective digital tools like automation and big data analytics in labor-intensive sectors and providing subsidies or financing to support smaller firms’ digitalization. These insights highlight digitalization’s uneven effects and provide a foundation for targeted policy design to enhance marine economic development.

Sex differences in the comorbidity between attention deficit-hyperactivity disorder and posttraumatic stress disorder: A systematic literature review and meta-analysis.

Sex differences in the comorbidity between attention deficit-hyperactivity disorder and posttraumatic stress disorder: A systematic literature review and meta-analysis.

The Impact of Financial Technology (FinTech) on Bank Risk-Taking and Profitability in Small Developing Island States: A Study of Fiji

With the increasing adoption of technologies such as mobile banking and blockchain, the banking sector in developing and emerging economies is experiencing both opportunities and challenges. This study examines the impact of FinTech on bank risk-taking and profitability in the small island economy of Fiji, spanning the period from 2000 to 2024. We employ a fixed-effects model and conduct robustness checks using random effects, pooled ordinary least squares (OLS), and the generalized method of moments (GMM) method, focusing on seven banks (five commercial banks and two non-bank financial institutions). Our analysis evaluates the effect of FinTech while controlling for other bank-specific factors that may influence risk-taking and profitability. The results indicate that FinTech development significantly reduces bank risk-taking and enhances profitability, suggesting a positive and substantial impact on financial performance and stability. The findings highlight the need for banks operating in Fiji and similar small economies to continue and expand their investments in FinTech innovations. Furthermore, the study suggests that regulatory bodies and policymakers should strengthen institutional and regulatory frameworks to support and guide FinTech’s evolution within the banking sector.

A prospective study of risk factors and new prediction model for inpatient aggression in a Turkish forensic psychiatric cohort with psychotic illness.

A prospective study of risk factors and new prediction model for inpatient aggression in a Turkish forensic psychiatric cohort with psychotic illness.

Panel Data Regression Approach to Identify Factors Affecting Unemployment in East Java Province

The Open Unemployment Rate (OOP) in East Java Province is a multidimensional problem influenced by economic and social factors, with significant disparities between districts/cities. This study analyses the effect of Poverty Percentage, Labour Force Participation Rate (TPAK), and Economic Growth on the open unemployment rate using a panel data regression approach to accommodate spatial and temporal heterogeneity. Cross-section (38 districts/cities) and time series (2019-2021) data were analysed through three models: Common Effect Model (CEM), Fixed Effect Model (FEM), and Random Effect Model (REM). The results of statistical tests (Chow, Hausman, and Lagrange Multiplier) show the FEM as the best model with a coefficient of determination of 0.555, explaining 55.5% of the variation in the unemployment rate. The FEM estimation reveals that the Poverty Percentage has a significant positive effect on increasing the unemployment rate, while Economic Growth has a negative impact on reducing the unemployment rate. This finding confirms the need for policies focused on poverty alleviation and increasing economic growth based on regional leading sectors. This study enriches the methodological literature through the application of FEM that controls for region-specific heterogeneity, while providing practical recommendations for policy makers in designing precise unemployment reduction interventions, such as skills training based on industry needs and strengthening labour-intensive programmes.