Effects Meta-analysis Research Articles

Too old to be a diversity hire: Choice bundling shown to increase gender-diverse hiring decisions fails to increase age diversity.

Past research has shown that people are more likely to make the decision to hire candidates whose gender would increase group diversity when making multiple hiring choices in a bundle (i.e., when selecting multiple team members simultaneously) compared to making choices in isolation (i.e., when selecting a single team member). However, it is unclear if this bundling effect extends to age diversity and the selection of older candidates, as older workers are often the target of socially acceptable negative stereotypes and bias in recruitment, leaving them unemployed for longer than their younger counterparts. Across five preregistered experiments (total N = 4,096), we tested if the positive effect of bundling on diversity of selections extends to older candidates in hiring decisions. We found evidence of bias against older job candidates in hiring decisions but found inconsistent effects of choice bundling on the selection of older candidates across experiments. An effect of bundling was found in two of five experiments, with no meta-analytic effect found across the five studies. Making older candidates more competitive and introducing a diversity statement aimed at increasing their selection both significantly increased older candidate selections, but failed to activate the bundling effect. We discuss the theoretical implications for choice bundling interventions and for age as a diversity characteristic to support the design of interventions that meet the challenges of an aging workforce. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Lifespan trajectories of negative and positive affect: A coordinated analysis of 14 longitudinal studies

Lifespan developmental theories suggest age-related shifts in motivation, cognition, emotion regulation, and stressor experience lead to changes in mean levels of negative and positive affect across the lifespan. The present research used coordinated data analysis to examine mean-level affective trajectories in 186,752 participants ranging from 11–104 years old across 14 longitudinal studies. Random-effects models were used to estimate meta-analytic effect sizes. On average, negative affect decreased until early older adulthood, and then remained stable throughout older adulthood. Meanwhile, positive affect remained stable across most of the younger and middle-aged adult lifespan, before starting its descent in later middle-aged adulthood and continuing to decline throughout older adulthood. Studies with older samples showed a clearer flattening effect of negative affect and steeper decline of positive affect in late-life relative to younger samples. These findings suggest that lifespan developmental affect trajectories are nuanced and not a direct inverse of each other.

Group-based versus individual parenting programs: A meta-analysis of effects on parents.

Parenting programs aim to motivate change in parents' behaviors, perceptions, and knowledge to promote desirable changes in children's adjustment and behavior. Parenting programs are typically delivered in a group-based or individual format, and it is unknown which format most effectively supports parents. On the one hand, group-based programs may be more effective since they provide access to peer-based support. On the other hand, individual programs may be more successful since they offer a tailored approach. Therefore, this meta-analysis investigated which delivery format is most effective in optimizing child behavior management (i.e., positive reinforcement and nonviolent discipline), parenting stress, and parental depressive symptoms. Studies were selected from the systematic review by Backhaus et al. (2023). Our sample included evaluations of 121 group-based and 41 individual programs based on social learning theory principles. Robust variance estimation indicated that parents' child behavior management and parenting stress improved in both delivery formats. In contrast, parental depressive symptoms improved only in group-based programs. Our findings suggest that whether parents benefit more from a group-based or individual program in part depends on the outcome examined. Therefore, it is important for clinicians to understand parents' goals to effectively guide them toward the most appropriate parenting program delivery format. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Supplemental Material for Group-Based Versus Individual Parenting Programs: A Meta-Analysis of Effects on Parents

Supplemental Material for Group-Based Versus Individual Parenting Programs: A Meta-Analysis of Effects on Parents

Questioning the Reciprocal Effects Model of Academic Self-Concept and Achievement: A Reanalysis of a Meta-Analysis of Longitudinal Studies and a Simulation

A recent meta-analysis claimed to provide evidence that academic self-concept and achievement have reciprocal prospective effects on each other (reciprocal effects model). However, prospective effects were estimated while adjusting for a prior measurement of the outcome, and this method is susceptible to spurious findings due to correlations with residuals and regression to the mean. Here we re-analyze the meta-analytic effects and show that different plausible models can support opposing claims: either that self-concept had an increasing or a decreasing effect on achievement, and vice versa. Consequently, claims beyond a positive cross-sectional correlation between academic self-concept and achievement, including the reciprocal effects model, can be questioned. The findings were validated by analyses of simulated data, which indicated that true prospective effects were not necessary for the observed meta-analytic associations. We further propose the extended skill development model (ESDM) as a more parsimonious alternative to the reciprocal effects model.

Causally interpretable meta-analysis combining aggregate and individual participant data

Abstract Recent work in causally-interpretable meta-analysis (CIMA) has bridged the gap between traditional meta-analysis and causal inference. While traditional meta-analysis results generally do not apply to any well-defined population, CIMA approaches specify a target population to which meta-analytic treatment effect estimates are transported. While theoretically attractive, these approaches currently have some practical limitations. Most assume that all studies in the meta-analysis have individual participant data (IPD), which is rare in practice because most trials share only aggregate data. We propose a method to perform CIMA using a combination of aggregate data and IPD. This method borrows information from studies with IPD to augment the aggregate data and create aggregate-matched synthetic IPD (AMSIPD), which can be used readily in the existing CIMA framework. By allowing use of both aggregate data and IPD, the method opens CIMA to more applications and can avoid biases arising from using only studies with IPD. We present a case study and simulations showing the AMSIPD approach is promising and merits further investigation as an advancement of CIMA.

Deep brain stimulation targets in drug-resistant epilepsy: Systematic review and meta-analysis of effectiveness and predictors of response

PurposeAnterior nucleus of the thalamus (ANT) is the only deep brain stimulation (DBS) target that is approved by the FDA for treatment of drug-resistant epilepsy (DRE). Hippocampus (HC) and centromedian nucleus (CMN) have been reported as potential DBS targets for DRE. This study aimed to assess the effectiveness and predictors of response among DRE patients treated with DBS in general and among ANT, HC and CMN DBS-targets. MethodsA systematic search was executed on PubMed, SCOPUS and the Cochrane Central Register of Controlled Trials (CENTRAL) electronic databases between Jan 1, 2000 and June 29, 2020. Patients with DRE who underwent DBS treatment with at least three months of follow-up were included. Individual patient data (IPD) meta-analysis was conducted on DBS studies with available IPD. Response was defined as ≥50 % reduction in seizures frequency. Responders group was compared with non-responders group in terms of demographics, epilepsy/seizure characteristics, MRI findings, and DBS targets and duration of use. Subsequently, predictors of response to different DBS targets were investigated. ResultsThirty-nine studies with a total of 296 patients (ANT: 69 %, HC: 11 %, CMN: 21 %) were included. The responders group constituted of 209 patients (70.6 %). The response was significantly higher in patients with generalized seizures compared to those with focal seizures (93.2% vs 63.9 %; p < 0.001). Response was significantly higher with CMN (83.9 %) and HC (77.4 %) compared with ANT (65.5 %) as DBS targets (p = 0.014). Response was also significantly associated with longer duration of DBS use (p = 0.008). The responder rate was higher among the patients with lesional MRIs (76.7 %) than those with non-lesional MRIs (66.7 %), but with no statistically significant difference (p = 0.134). Age, gender, epilepsy etiology, onset zone of focal seizures, and previous use of VNS had no significant differences between the responders and non-responders. A binary logistic regression including the seizure type, MRI findings, DBS targets, and DBS duration showed, after controlling for confounders, that the duration of DBS use was the only significant predictor of response (adjusted OR 1.061; 95 % CI 1.019–1.106; p = 0.005). Regarding DBS targets, the response rate in patients with symptomatic etiology was significantly higher with HC or CMN targets than the ANT (p = 0.003). In patients with non-lesional MRI, response rate was significantly higher with the CMN target compared to the other two targets (p = 0.008). ConclusionDBS proves to be effective in DRE, with progressive success upon longer treatment and possibility of improving quality of life. In addition to focal seizures, DBS has potential for treating generalized seizures as well. While the ANT stands as the most utilized and only approved DBS target for DRE, CMN and HC are alternative targets with high seizure control potential. Patients with symptomatic etiology showed significant seizure reduction when HC or CMN were targeted. Studies revealed noticeable effectiveness of CMN-DBS in treating patients with non-lesional MRI. Despite ANT prominence in research, our findings suggest promising outcomes with CMN and HC, emphasizing the need for future larger-scale comparative clinical trials to better understand the efficacy of different DBS targets.

Meta-analysis of effectiveness and safety of proteasome inhibitor-dependent maintenance treatment for multiple myeloma a systematic review

BackgroundEven with significant advancements, treating multiple myeloma (MM) remains difficult. At present, the main treatment methods include combined treatment of stem cell transplantation, drug treatment, etc. With the clarification of the molecular biological mechanism of MM, as well as the in-depth study of the internal signal of myeloma cells and the microenvironment of MM patients, more and more new drugs targeting myeloma and microenvironment are gradually used in clinical maintenance treatment, such as inhibit the proteosome: ixazomib, bortezomib and carfilzomib, immune - modulators: thalidomide and lenalidomide, monoclonal antibodies, etc. have made great progress in MM maintenance treatment. With the continuous development of proteasome inhibitor maintenance treatment in MM, the prognosis of the disease has been significantly improved. Our aim is to evaluate the effectiveness and adverse reactions of proteasome inhibitors in maintenance therapy for multiple myeloma, providing new ideas for clinical medication. MethodsFour databases containing randomized controlled studies on the effectiveness and safety of proteasome inhibitors in the maintenance therapy of multiple myeloma are retrieved by the computer. Once the quality of the literature has been thoroughly evaluated, run the data via the RevMan 5.3 software. ResultsEventually 8 studies were added in this systematic review. Compared with the placebo group, proteasome inhibitor in maintenance treatment of multiple myeloma patients with prolonged the survival without progression and overall existence. 5 studies reported the peripheral neuropathy of multiple myeloma in the treatment group compared to placebo group, which was remarkably greater (OR: 1.98; 95 % Cl: 1.35, 2.92; P < 0.001) compared to placebo group, Serious adverse events (OR: 1.60; 95 % Cl: 1.19, 2.14; P < 0.01), Rash (OR: 2.23; 95 % Cl: 1.62, 3.05; P < 0.001) and Vomiting (OR: 5.12; 95 % Cl: 3.36, 7.80; P < 0.001). The Serious adverse events of the treatment group were remarkably greater compared with the untreated group (OR: 1.60; 95 % Cl: 1.19, 2.14; P < 0.01). ConclusionThe study results proposed that proteasome inhibitors are effective in the multiple myeloma maintenance treatment compared with the placebo group. Bortezomib has certain advantages in prolonging PFS, followed by ixazomib and carfilzomib in terms of efficacy. Bortezombib may be superior to carfilzombib in extending OS. However, the adverse reactions caused by proteasome inhibitors, such as Peripheral neuropathy, Serious adverse events, Rash, Vomiting, etc., should be paid enough attention.

Blood Pressure Control Among Diabetic Patients in the Eastern Mediterranean Region: A Systematic Review and Meta-Analysis

The control of blood pressure (BP) is a challenge in diabetic patients and is associated with adverse outcomes of diabetes. In this systematic review and metaanalysis, we investigated the BP control rate among hypertensive diabetic patients in the Eastern Mediterranean Region (EMR) countries. We systematically searched PubMed, Scopus, Embase, Cochrane, and Web of Science databases up to January 2023 for observational studies on BP control among hypertensive diabetic patients in all EMR countries. We included studies reporting the proportion of hypertensive, type 2 diabetic patients with controlled BP, defined as systolic/diastolic BP < 140/90 or <130/80 mmHg. Study quality was assessed using modified STROBE guidelines, and a random-effect meta-analysis was conducted to pool prevalence data and calculate overall rates. Subgroup analysis was performed by gender, study design, country, and BP control cut-offs (140/90 and 130/80). Among the 1949 retrieved studies, 20 studies assessing 27956 individuals were included. The proportion of BP control regardless of cut-off points was 36.8% (95% CI=29.1%45.3%) based on the studies reported for both genders.The prevalence was 53.2% (95% CI=36.1%- 69.6%) and 43.5% (95% CI=20.0%-70.3%) based on the studies reported just for women or men, respectively. Our findings indicate that BP control targets are not successfully achieved in hypertensive diabetic patients in the Eastern Mediterranean region. It is recommended to place greater emphasis on the quality of hypertension care in the management of type 2 diabetes.

Addressing Endogeneity in Meta-Analysis: Instrumental Variable Based Meta-Analytic Structural Equation Modeling

In management research, meta-analysis is often used to aggregate findings from observational studies that lack random assignment to predictors (e.g., surveys), which may pose challenges in making accurate inferences due to the correlational nature of effect sizes. To improve inferential accuracy, we show how instrumental variable (IV) methods can be integrated into meta-analysis to help researchers obtain unbiased estimates. Our IV-based meta-analytic structural equation modeling (IV-MASEM) method relies on the fact that IVs can be incorporated into SEM, and meta-analytic effect sizes from correlational research can be used for MASEM. Conveniently, IV-MASEM does not require that each primary study measures all relevant variables, and it can address typical types of endogeneity, such as omitted variable bias. We clarify how the principles of IV-SEM can be applied to MASEM and then conduct three simulations to study the validity of IV-MASEM versus Univariate Meta-Analyses (UMA) and MASEMs that exclude IVs when the instruments were appropriate, inappropriate, and missing from a subset of primary studies. We also offer an illustrative study to demonstrate how to apply IV-MASEM to address endogeneity concerns in meta-analysis, which includes a new R function to test the qualifying conditions for IVs. We conclude with limitations and future directions for IV-MASEM.

Effects of dietary Adansonia digitata L. (baobab) seed meal on growth performance and carcass characteristics of broiler chickens: A systematic review and meta-analysis

Abstract The seeds of lesser-known tropical legume trees are currently being promoted as a cost-effective method of increasing broiler productivity, especially in low- and middle-income countries. Several feeding trials have evaluated the effects of baobab seed meal (BSM) on broiler chicken productivity. However, due to differences in experimental conditions among feeding trials, drawing broad conclusions using this large volume of data appears difficult. Thus, the meta-analytic effect of BSM on growth performance [i.e., feed intake, feed conversion ratio (FCR), and body weight gain (BWG)] and carcass characteristics of broilers were investigated using 14 peer-reviewed published articles. These articles were retrieved via a systematic search conducted on Google Scholar, ScienceDirect, Elicit.com, and PubMed databases. The effect size was calculated via a random effect model, and results were expressed as standardised mean differences (SMD) at 95% confidence intervals. The pooled results showed that broilers fed BSM had significantly lower BWG (SMD = −0.77; −0.19, −0.30; p &lt; 0.001), dressed carcass weight (SMD = −0.84; −1.44, −0.23; p = 0.007), and higher FCR (SMD = 0.55; 0.19, 0.91; p &lt; 0.001) than those fed control diets. However, feed intake, dressing percentage, and weights of breast, thigh, and drumstick were not significantly affected. Subgroup analyses showed that the Marshall strain-fed BSM-based diets had significantly heavier BWG (p &lt; 0.001) than the Hubbard, Ross, and Anak strains. Similarly, results revealed that broilers fed soaked and roasted BSM had significantly better FCR and BWG than broilers fed sundried and fermented BSM. Broilers fed BSM-based diets from days 29–56 (SMD = 0.17; −0.51, 0.84; p = 0.622) and days 1−56 (SMD = −0.89; −1.41, −0.36; p &lt; 0.001) had significantly improved FCR compared to those offered BSM-based diets from days 1–21 (SMD = 2.58; 1.65, 3.51; p &lt; 0.001), days 1–28 (SMD = 0.85; 0.35, 1.34; p &lt; 0.001), and days 22–42 (SMD = 1.82; 1.02, 2.62; p &lt; 0.001). Similarly, broilers fed BSM-based diets from days 29–56 (SMD = 0.21; −0.38, 0.79; p = 0.484) and days 1−56 (SMD = 0.92; 0.16, 1.69; p = 0.018) had significantly higher BWG than those offered BSM-based diets from days 1–21 (SMD = −3.39; −4.41, −2.37; p &lt; 0.001), days 1–28 (SMD = −1.32; −1.91, −0.72; p &lt; 0.001), and days 22–42 (SMD = −2.24; −2.75, 1.73; p &lt; 0.001). Meta-regression revealed a low to moderate effect of processing methods, broiler strains, inclusion level, and feeding duration as covariates, explaining most of the sources of heterogeneity. In conclusion, broilers fed 1–10% of soaked, and roasted BSM from days 1 to 56 had improved growth performance parameters when compared to those on the control.

General mental ability testing and adverse impact in the United Kingdom: a meta-analysis with more than two million observations

ABSTRACT We review ethnic group differences on high-stakes General Mental Ability (GMA) tests based on 21st century UK data. Thereafter, we meta-analyse scores on 23 occupational, public sector, educational, military, or general-public selection tests, with a sample size exceeding two million. Relative to White GMA, the grand meta-analytic effect sizes (Cohen’s d) by major ethnic groups were: Mixed d = .14 (k = 24, N = 67,114), Blacks d = .65 (k = 32, N = 112,975), Asians d = .33 (k = 32, N = 311,695), and Other d = .49 (k = 24, N = 42,846). Further, although Chinese residents outscored White British residents (d = −.15, k = 20, N = 18,897), all other Asian ethnic groups scored slightly to substantially lower. For example, South Asians as a whole averaged d = .37; k = 13, N = 67,566. By subgroups, these averages were: Indians (d = .17, k = 10, N = 28,236), Pakistanis (d = .49, k = 9, N = 19,371), and Bangladeshi (d = .55, k = 7, N = 19,772). Implications for practice and theory are discussed.

How Much Have We Learned about Consumer Research? A Meta-Meta-Analysis

Abstract This meta-meta-analysis study quantifies the development of scientific knowledge in consumer research by summarizing the findings of 222 meta-analyses that together include 2481 meta-analytic effect sizes. The results provide an overview of how much we know and how knowledge has developed in consumer research over time. By explaining 7.8% variance (r = 0.28) in consumer-relevant dependent variables, the findings show that consumer research, a comparatively young discipline, is relatively effective at knowledge development compared to other disciplines. Furthermore, the accumulation of knowledge is significantly increasing, suggesting that our discipline is still in the growing phase of its life cycle and generating continuously improving explanations of consumer-related phenomena. The development of knowledge varies across consumer-relevant dependent variables, with strong explanations for relationships but significantly weaker ones for memory, affect, and attitudes. Moreover, the knowledge synthesized in meta-analyses is fairly—though not fully—representative of the content of primary research on consumers overall. The findings convey a future research agenda by identifying under-researched areas, advising on the selection of dependent variables, providing indicators for the expected contributions of future studies, suggesting implications for career strategies of consumer researchers, and discussing explanations for the observed knowledge growth effects.

Prospective effects of mindfulness on anxiety and depressive symptoms may be spurious: Simulated reanalysis of a meta-analytic cross-lagged panel analysis.

A recent meta-analysis claimed decreasing prospective effects of acting with awareness and non-reacting, two facets of dispositional mindfulness, on subsequent anxiety and depressive symptoms. However, the meta-analytic cross-lagged effects were estimated while adjusting for a prior measurement of the outcome variable and it is known that such adjusted cross-lagged effects may be spurious due to correlations with residuals and regression to the mean. We fitted competing models on simulations of the same meta-analytic data and found that prospective effects of the mindfulness facets on anxiety and depressive symptoms probably were spurious. It is important for researchers to be aware of limitations of adjusted cross-lagged effects, meta-analytically estimated or not, in order not to overinterpret findings.

Hospitality Front-line Employees: A Meta-Analysis of Emotion Management at Work

The main purpose of this study was to summarize extant empirical findings on how front-line service employees experience and manage emotions at work. When consolidated, the research on front-line employee emotions revealed mixed and contradictory results and knowledge gaps on workplace challenges of service-oriented employees. The PRISMA were followed for study selection, and the appraisal theory of emotions was used to classify the direct antecedents and outcomes of emotion management. To calculate meta-analytic effect sizes, comprehensive meta-analysis methodology wasapplied to analyze 79 studies (N=28,332). The summary effects of known antecedents, affective events (conflict, customer interactions), stimuli (personality characteristics), and workplace environment (support and display rules) on front-line employees’ emotion management were more modest than previously indicated. Organization, supervisor, and coworker support were found to be a moderator between conflict and employees’ emotion management. The most-researched outcomes of emotion management (burnout and job performance) also showed only modest effect sizes. Job satisfaction was a moderator between emotion management and job performance. The relationship between emotion management and customer-related antecedents and outcomes showed modest to small effect sizes. These results contribute to the ATE and highlight the knowledge gap on how customer emotions and behaviors affect front-line employees’ ability to manage their emotions and provide quality customer service and, in turn, how employee’s transference of emotions might influence customer satisfaction, loyalty, and trust. Managers should provide necessary support to mitigate the impact of affective events that may influence how front-line employees manage emotions at work to increase job satisfaction and performance.

Problematic meta-analyses: Bayesian and frequentist perspectives on combining randomized controlled trials and non-randomized studies

PurposeIn the literature, the propriety of the meta-analytic treatment-effect produced by combining randomized controlled trials (RCT) and non-randomized studies (NRS) is questioned, given the inherent confounding in NRS that may bias the meta-analysis. The current study compared an implicitly principled pooled Bayesian meta-analytic treatment-effect with that of frequentist pooling of RCT and NRS to determine how well each approach handled the NRS bias.Materials & methodsBinary outcome Critical-Care meta-analyses, reflecting the importance of such outcomes in Critical-Care practice, combining RCT and NRS were identified electronically. Bayesian pooled treatment-effect and 95% credible-intervals (BCrI), posterior model probabilities indicating model plausibility and Bayes-factors (BF) were estimated using an informative heavy-tailed heterogeneity prior (half-Cauchy). Preference for pooling of RCT and NRS was indicated for Bayes-factors > 3 or < 0.333 for the converse. All pooled frequentist treatment-effects and 95% confidence intervals (FCI) were re-estimated using the popular DerSimonian-Laird (DSL) random effects model.ResultsFifty meta-analyses were identified (2009–2021), reporting pooled estimates in 44; 29 were pharmaceutical-therapeutic and 21 were non-pharmaceutical therapeutic. Re-computed pooled DSL FCI excluded the null (OR or RR = 1) in 86% (43/50). In 18 meta-analyses there was an agreement between FCI and BCrI in excluding the null. In 23 meta-analyses where FCI excluded the null, BCrI embraced the null. BF supported a pooled model in 27 meta-analyses and separate models in 4. The highest density of the posterior model probabilities for 0.333 < Bayes factor < 1 was 0.8.ConclusionsIn the current meta-analytic cohort, an integrated and multifaceted Bayesian approach gave support to including NRS in a pooled-estimate model. Conversely, caution should attend the reporting of naïve frequentist pooled, RCT and NRS, meta-analytic treatment effects.

Comparison of Blood Concentration and Weight-Based Heparin and Protamine Dosing Strategies for Cardiopulmonary Bypass: A Systematic Review and Meta-Analysis.

The conventional method of heparin and protamine management during cardiopulmonary bypass (CPB) is based on total body weightwhich fails to account for the heterogeneous response to heparinin each patient. On the other hand, the literature is inconclusive on whether individualized anticoagulation management based on real-time blood heparin concentration improves post-CBP outcomes. We searched databases of Medline, Excerpta Medica dataBASE (EMBASE), PubMed, Cumulative Index to Nursing and Allied Health Literature (CINHL), and Google Scholar, recruiting randomized controlled trials (RCTs) and prospective studies comparing the outcomes of dosing heparinand/or protamine based on measured heparin concentration versus patient'stotal body weightfor CPB.Random effects meta-analyses and meta-regression were conducted to compare the outcome profiles. Primary endpoints include postoperative blood loss and the correlation with heparin and protamine doses, the reversal protamine and loading heparin dose ratio; secondary endpoints included postoperative platelet counts, antithrombin III, fibrinogen levels, activated prothrombin time (aPTT), incidences of heparin rebound, and re-exploration of chest wound for bleeding. Twenty-six studies, including 22 RCTs and four prospective cohort studies involving 3,810 patients, were included.Compared to body weight-based dosing, patients of individualized, heparin concentration-based group had significantly lower postoperative blood loss (mean difference (MD)=49.51mL, 95% confidence interval (CI): 5.33-93.71), lower protamine-to-heparin dosing ratio (MD=-0.20, 95% CI: -0.32~ -0.12), and higher early postoperative platelet counts (MD=8.83, 95% CI: 2.07-15.59). The total heparin doses and protamine reversal were identified as predictors of postoperative blood loss by meta-regression. There was a significant correlation between the doses of heparin and protamine with postoperative blood loss; therefore, précised dosing of both could be critical for reducingbleeding and transfusion requirements. Data from the enrolled studies indicated that compared to conventional weight-based dosing, individualized, blood concentration-based heparin and protamine dosing may have outcome benefits reducing postoperative blood loss.The dosing calculation of heparin based on the assumption of a one-compartment pharmacokinetic/pharmacodynamic (PK/PD) model and linear relationship between the calculated dose and blood heparin concentration may be inaccurate.With the recent advancement of the technologies of machine learning, individualized, precision management of anticoagulation for CPB may be possible in the near future.

Spurious prospective effects between general and domain-specific self-esteem: A reanalysis of a meta-analysis of longitudinal studies.

A recent meta-analysis, of 38 studies with data from 43 independent samples (total N = 24,668), claimed evidence for positive reciprocal prospective effects, and hence for both top-down and bottom-up processes, between general and domain-specific self-esteem. However, the meta-analytic cross-lagged effects were estimated while adjusting for a prior measurement of the outcome variable and it is known that such adjusted cross-lagged effects may be spurious due to correlations with residuals and regression to the mean. In the present reanalyses, we found all of the prospective effects to be spurious. Consequently, claims about increasing prospective effects and top-down and bottom-up processes between general and domain-specific self-esteem can be questioned. It is important for researchers to be aware of the limitations of cross-lagged panel analyses, and of analyses of correlational data in general, in order not to overinterpret findings.

Comparison of statistical methods used to meta-analyse results from interrupted time series studies: an empirical study

BackgroundThe Interrupted Time Series (ITS) is a robust design for evaluating public health and policy interventions or exposures when randomisation may be infeasible. Several statistical methods are available for the analysis and meta-analysis of ITS studies. We sought to empirically compare available methods when applied to real-world ITS data.MethodsWe sourced ITS data from published meta-analyses to create an online data repository. Each dataset was re-analysed using two ITS estimation methods. The level- and slope-change effect estimates (and standard errors) were calculated and combined using fixed-effect and four random-effects meta-analysis methods. We examined differences in meta-analytic level- and slope-change estimates, their 95% confidence intervals, p-values, and estimates of heterogeneity across the statistical methods.ResultsOf 40 eligible meta-analyses, data from 17 meta-analyses including 282 ITS studies were obtained (predominantly investigating the effects of public health interruptions (88%)) and analysed. We found that on average, the meta-analytic effect estimates, their standard errors and between-study variances were not sensitive to meta-analysis method choice, irrespective of the ITS analysis method. However, across ITS analysis methods, for any given meta-analysis, there could be small to moderate differences in meta-analytic effect estimates, and important differences in the meta-analytic standard errors. Furthermore, the confidence interval widths and p-values for the meta-analytic effect estimates varied depending on the choice of confidence interval method and ITS analysis method.ConclusionsOur empirical study showed that meta-analysis effect estimates, their standard errors, confidence interval widths and p-values can be affected by statistical method choice. These differences may importantly impact interpretations and conclusions of a meta-analysis and suggest that the statistical methods are not interchangeable in practice.

Investigation of bias due to selective inclusion of study effect estimates in meta-analyses of nutrition research.

We aimed to explore, in a sample of systematic reviews (SRs) with meta-analyses of the association between food/diet and health-related outcomes, whether systematic reviewers selectively included study effect estimates in meta-analyses when multiple effect estimates were available. We randomly selected SRs of food/diet and health-related outcomes published between January 2018 and June 2019. We selected the first presented meta-analysis in each review (index meta-analysis), and extracted from study reports all study effect estimates that were eligible for inclusion in the meta-analysis. We calculated the Potential Bias Index (PBI) to quantify and test for evidence of selective inclusion. The PBI ranges from 0 to 1; values above or below 0.5 suggest selective inclusion of effect estimates more or less favourable to the intervention, respectively. We also compared the index meta-analytic estimate to the median of a randomly constructed distribution of meta-analytic estimates (i.e., the estimate expected when there is no selective inclusion). Thirty-nine SRs with 312 studies were included. The estimated PBI was 0.49 (95% CI 0.42-0.55), suggesting that the selection of study effect estimates from those reported was consistent with a process of random selection. In addition, the index meta-analytic effect estimates were similar, on average, to what we would expect to see in meta-analyses generated when there was no selective inclusion. Despite this, we recommend that systematic reviewers report the methods used to select effect estimates to include in meta-analyses, which can help readers understand the risk of selective inclusion bias in the SRs.