Heterogeneity In Effect Sizes Research Articles

Bayesian Meta-Analysis of Health State Utility Values: A Tutorial with a Practical Application in Heart Failure.

Researchers incorporate health state utility values as inputs to inform economic models. However, for a particular health state or condition, multiple utility values derived from different studies typically exist and a single study is often insufficient to represent the best available source of utility needed to inform policy decisions. The purpose of this paper is to provide an introductory guidance for conducting Bayesian meta-analysis of health state utility values to generate a single parameter input for economic evaluation, using R. The tutorial is illustrated using data from a systematic review of health state utilities of patients with heart failure, with 21 studies that reported utilities measured using the EuroQol-5D (EQ-5D). Explanations, key considerations and suggested readings are provided for each step of the tutorial, adhering to a clear workflow for conducting Bayesian meta-analysis: (1) setting-up the data; (2) employing methods to impute missing standard deviations; (3) defining the priors; (4) fitting the model; (5) diagnosing model convergence; (6) interpreting the results; and (7) performing sensitivity analyses. The posterior distributions for the pooled effect size (i.e. mean health state utility) and between-study heterogeneity are discussed and interpreted in light of the data, priors and models used. We hope that this tutorial will foster interest in Bayesian methods and their applications in the meta-analysis of utilities.

Meta-analysis of the association between gratitude and loneliness.

Gratitude is a positive social emotion that involves recognizing that others have brought benefits into one's life. Loneliness, on the other hand, is an unpleasant emotion resulting from a perceived lack of social connectedness. Although previous studies have reported an inverse association between gratitude and loneliness, these studies have not been systematically examined in a single review. To address this gap in the literature, we conducted a random-effects meta-analysis to examine the association between gratitude and loneliness. Analysis of 26 studies revealed a moderate sized effect (mean Fisher's z transformed correlation, zr = -.406, 95% confidence interval [CI] = -.463, -.349; mean back-transformed correlation, r = -.385, 95% CI = -.433, -.335). To complement these effect sizes, we calculated a probability-based common language effect size for correlations. Random-effects homogeneity testing suggested the presence of effect size heterogeneity. Analyses of both continuous and categorical moderators were non-significant, indicating that these variables did not influence effect size magnitude. Furthermore, publication bias tests suggested that our results were not influenced by unpublished studies. Finally, we proposed several statistical and clinical recommendations for future research. Regarding the latter, we offered suggestions for modifying gratitude enhancement programs with the aim of reducing loneliness.

Maternal and paternal sensitivity: Key determinants of child attachment security examined through meta-analysis.

Sensitive caregiving behavior, which involves the ability to notice, interpret, and quickly respond to a child's signals of need and/or interest, is a central determinant of secure child-caregiver attachment. Yet, significant heterogeneity in effect sizes exists across the literature, and sources of heterogeneity have yet to be explained. For all child-caregiver dyads, there was a significant and positive pooled association between caregiver sensitivity and parent-child attachment (r = .25, 95% CI [.22, .28], k = 174, 230 effect sizes, N = 22,914). We also found a positive association between maternal sensitivity and child attachment security (r = .26, 95% CI [.22, .29], k = 159, 202 effect sizes, N = 21,483), which was equivalent in magnitude to paternal sensitivity and child attachment security (r = .21, 95% CI [.14, 27], k = 22, 23 effect sizes, N = 1,626). Maternal sensitivity was also negatively associated with all three classifications of insecure attachment (avoidant: k = 43, r = -.24 [-.34, -.13]; resistant: k = 43, r = -.12 [-.19, -.06]; disorganized: k = 24, r = -.19 [-.27, -.11]). For maternal sensitivity, associations were larger in studies that used the Attachment Q-Sort (vs. the Strange Situation), used the Maternal Behavior Q-Sort (vs. Ainsworth or Emotional Availability Scales), had strong (vs. poor) interrater measurement reliability, had a longer observation of sensitivity, and had less time elapse between assessments. For paternal sensitivity, associations were larger in older (vs. younger) fathers and children. These findings confirm the importance of both maternal and paternal sensitivity for the development of child attachment security and add understanding of the methodological and substantive factors that allow this effect to be observed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Do corporate hedge theories explain the natural hedge strategies of firms? A meta-analytic review.

This meta-analysis of 54 empirical studies examines the determinants of natural hedging. Our findings reveal that firm’s risk exposure, economies of scale, and strategic considerations prompt natural hedge. Financial distress and underinvestment theory also partially explain the preference for natural hedge; however, their effect’s economic relevance is low. Factors influencing natural hedging differ across geographical regions and impact the choice of natural hedging strategies. For instance, highly profitable firms prefer foreign debt, whereas highly leveraged firms prefer operational modifications as natural hedge strategy. Data sources, model specifications, econometric methods, and journal rankings further explain heterogeneity in effect sizes across studies.

An approach to identify gene-environment interactions and reveal new biological insight in complex traits

There is a long-standing debate about the magnitude of the contribution of gene-environment interactions to phenotypic variations of complex traits owing to the low statistical power and few reported interactions to date. To address this issue, the Gene-Lifestyle Interactions Working Group within the Cohorts for Heart and Aging Research in Genetic Epidemiology Consortium has been spearheading efforts to investigate G × E in large and diverse samples through meta-analysis. Here, we present a powerful new approach to screen for interactions across the genome, an approach that shares substantial similarity to the Mendelian randomization framework. We identify and confirm 5 loci (6 independent signals) interacted with either cigarette smoking or alcohol consumption for serum lipids, and empirically demonstrate that interaction and mediation are the major contributors to genetic effect size heterogeneity across populations. The estimated lower bound of the interaction and environmentally mediated heritability is significant (P < 0.02) for low-density lipoprotein cholesterol and triglycerides in Cross-Population data. Our study improves the understanding of the genetic architecture and environmental contributions to complex traits.

Control of false discoveries in grouped hypothesis testing for eQTL data

BackgroundExpression quantitative trait locus (eQTL) analysis aims to detect the genetic variants that influence the expression of one or more genes. Gene-level eQTL testing forms a natural grouped-hypothesis testing strategy with clear biological importance. Methods to control family-wise error rate or false discovery rate for group testing have been proposed earlier, but may not be powerful or easily apply to eQTL data, for which certain structured alternatives may be defensible and may enable the researcher to avoid overly conservative approaches.ResultsIn an empirical Bayesian setting, we propose a new method to control the false discovery rate (FDR) for grouped hypotheses. Here, each gene forms a group, with SNPs annotated to the gene corresponding to individual hypotheses. The heterogeneity of effect sizes in different groups is considered by the introduction of a random effects component. Our method, entitled Random Effects model and testing procedure for Group-level FDR control (REG-FDR), assumes a model for alternative hypotheses for the eQTL data and controls the FDR by adaptive thresholding. As a convenient alternate approach, we also propose Z-REG-FDR, an approximate version of REG-FDR, that uses only Z-statistics of association between genotype and expression for each gene-SNP pair. The performance of Z-REG-FDR is evaluated using both simulated and real data. Simulations demonstrate that Z-REG-FDR performs similarly to REG-FDR, but with much improved computational speed.ConclusionOur results demonstrate that the Z-REG-FDR method performs favorably compared to other methods in terms of statistical power and control of FDR. It can be of great practical use for grouped hypothesis testing for eQTL analysis or similar problems in statistical genomics due to its fast computation and ability to be fit using only summary data.

Coordinated distributed experiments in ecology do not consistently reduce heterogeneity in effect size

Ecological meta‐analyses usually exhibit high relative heterogeneity of effect size: most among‐study variation in effect size represents true variation in mean effect size, rather than sampling error. This heterogeneity arises from both methodological and ecological sources. Methodological heterogeneity is a nuisance that complicates the interpretation of data syntheses. One way to reduce methodological heterogeneity is via coordinated distributed experiments, in which investigators conduct the same experiment at different sites, using the same methods. We tested whether coordinated distributed experiments in ecology exhibit 1) low heterogeneity in effect size, and 2) lower heterogeneity than meta‐analyses, using data on 17 effects from eight coordinated distributed experiments, and 406 meta‐analyses. Consistent with our expectations, among‐site heterogeneity typically comprised &lt;50% of the variance in effect size in distributed experiments. In contrast, heterogeneity within and among studies typically comprised &gt;90% of the variance in effect size in meta‐analyses. However, this difference largely reflected the small size of most coordinated distributed experiments, and was no longer significant after controlling for size (number of studies or sites). These results are consistent with the hypothesis that methodological heterogeneity rarely comprises a substantial fraction of variance in effect size in ecology. We also conducted pairwise comparisons of absolute heterogeneity between coordinated distributed experiments and meta‐analyses on the same topics. Coordinated distributed experiments did not consistently exhibit lower absolute heterogeneity in effect size than meta‐analyses on the same topics. Our findings suggest that coordinated distributed experiments rarely increase uniformity of results by reducing methodological heterogeneity. Our results help refine the numerous distinct reasons for conducting coordinated distributed experiments.

Religiosity predicts prosociality, especially when measured by self-report: A meta-analysis of almost 60 years of research.

This meta-analysis explores the long-standing and heavily debated question of whether religiosity is associated with prosocial and antisocial behavior at the individual level. In an analysis of 701 effects across 237 samples, encompassing 811,663 participants, a significant relationship of r = .13 was found between religiosity and prosociality (and antisociality, which was treated as its inverse). Nevertheless, there was substantial heterogeneity of effect sizes, and several potential moderators were explored. The effect was most heavily moderated by the type of measurement used to assess prosocial or antisocial behavior. Religiosity correlated more strongly with self-reported prosociality (r = .15) than with directly measured prosocial behavior (r = .06). Three possible interpretations of this moderation are discussed, namely, that (a) lab-based methods do not accurately or fully capture actual religious prosociality; (b) the self-report effect is explained by religious self-enhancement and overreports actual prosociality; or (c) both religiosity and self-reported prosociality are explained by self-enhancement. The question of whether religiosity more strongly positively predicts prosociality or negatively predicts antisociality is also explored. This moderation is, at most, weak. We test additional potential moderators, including the aspect of religiosity and type of behavior measured, the ingroup or outgroup nature of the recipient, and study characteristics. Finally, we recommend a shift in how researchers investigate questions of religiosity and prosociality in the future. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Comparison of Twin Block appliance and Herbst appliance in the treatment of Class II malocclusion among children: a meta-analysis

BackgroundOur meta-analysis aimed to evaluate the efficacy of applying Herbst and Twin Block appliances in the treatment of Class II malocclusion among children.MethodsDatabases, including PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), China VIP Database (VIP), and Wanfang were thoroughly searched from inception to August 9, 2023. The outcomes included skeletal, dental, and soft tissue changes. The weighted mean difference (WMD) was used as the effect indicator, and the effect size was expressed with a 95% confidence interval (CI). The heterogeneity of each outcome effect size was tested, and the heterogeneity statistic I2 ≥ 50% was analyzed by the random-effect model, otherwise, the fixed-effect model was conducted. Sensitivity analysis was performed.ResultsA total of 12 studies involving 574 patients were included in this meta-analysis. Herbst appliance had a statistically significant increase in mandibular body length (WMD: 1.44, 95% CI: 0.93 to 1.96, P < 0.001) compared with the Twin Block appliance. More increases in angle and distance of L1 to mandibular plane (MP) were found in the Herbst appliance compared with the Twin Block appliance. Significant and greater improvements in molar relationship (WMD: 0.79, 95% CI: 0.28 to 1.29, P = 0.002), posterior facial height (WMD: -1.23, 95% CI: -2.08 to -0.38, P = 0.005), convexity angle (WMD: -1.89, 95% CI: -3.12 to -0.66, P = 0.003), and Sella-Nasion plane angle (U1 to SN) (WMD: 3.34, 95% CI: 2.25 to 4.43, P < 0.001) were achieved in the Twin Block appliance. Herbst and Twin Block appliances produced similar effects in the skeletal and dentoalveolar changes including Sella-Nasion-point A (SNA), Sella-Nasion-point B, point A-Nasion-point B (ANB), overjet, and overbite.ConclusionAs the findings revealed both Herbst and Twin Block appliances contributed successfully to the correction of Class II malocclusion. Compared with the Twin Block appliance, the Herbst appliance may have more advantages in mandibular bone movement. Twin Block therapy resulted in more improvement in the aesthetics of the face.

Antidotal Effects of the Antihistamine Diphenhydramine Against Cholinesterase Inhibitor Poisoning: A Meta-Analysis of Median Lethal Doses in Experimental Animals.

The H1-antihistamine diphenhydramine antagonizes cholinesterase inhibitor poisoning in various animal species. One aspect of acute antidotal actions of diphenhydramine is increasing the median lethal doses (LD50) of toxicants. The objective of this meta-analysis was to assess the antidotal action of diphenhydramine against short-term toxicity (LD50) of cholinesterase inhibitors in experimental animals. The experimental studies selected were according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. They were conducted in laboratory animals (mice, rats, and chicks) to determine acute LD50 values of cholinesterase inhibitors (organophosphates, carbamates, and imidocarb) under the influence of diphenhydramine vs. controls. Twenty-eight records were selected from 12 studies on mice (n= 242), rats (n= 27), and young chicks (n= 128). The forest plot of randomized two-group meta-analysis assessed effect size, subgroup analysis, drapery prediction, heterogeneity, publication bias-funnel plot as well as one-group proportions meta-analysis of percent protection. Diphenhydramine significantly increased the combined effect size (i.e. increased LD50) in intoxicated experimental animals in comparison to controls (-3.71, standard error (SE) 0.36, 95%CI -4.46, -2.97). The drapery plot proposed a wide range of confidence intervals. The I2 index of heterogeneity of the combined effect size was high at 81.03% (Q= 142.3, p < 0.0001). Galbraith regression also indicated data heterogeneity; however, the normal quantile plot indicated no outliers. Subgroup analysis indicated significantly high heterogeneity with organophosphates (I2 = 63.72%) and carbamates (I2 = 76.41%), but low with imidocarb (I2 = 51.48%). The funnel plot and Egger regression test (t= -13.7, p < 0.0001) revealed publication bias. The median of the diphenhydramine protection ratio was 1.655, and the related forest plot of one group proportion meta-analysis revealed a statistically high level of protection (0.594, SE0.083, 95%CI 0.432, 0.756), withhigh heterogeneity (I2= 99.86). The risk of bias assessment was unclear, while the total score (16 out of 20) of each study leaned towards the side of the low risk of bias. In conclusion, the meta-analysis of LD50 values indicated that diphenhydramine unequivocally protected experimental animals from the acute toxicity of cholinesterase inhibitors. The drug could be an additional antidote against acute poisoning induced by cholinesterase inhibitors, but a word of caution: it is not to be considered as a replacement for the standard antidote atropine sulfate. Further studies are needed to examine the action of diphenhydramine on adverse chronic effects of cholinesterase inhibitors.

Sexually transmitted diseases and HIV co-infection among adult male patients in the 2022 monkeypox outbreak: a systematic review and meta-analysis

Aim. This meta-analysis estimates the prevalence of sexually transmitted diseases (STIs) and HIV infection among male patients diagnosed with Monkeypox during the 2022 outbreak. The study also explores contextual factors associated with higher risk of monkeypox infection. Methods. A systematic review of literature was initially conducted through PubMed/ Medline, Scopus, and Google Scholar to retrieve observational studies describing demographics and medical characteristics of Monkeypox patients affected in the 2022 outbreak. The System for the Unified Management, Assessment, and Review of Information -Joanna Briggs Institute (SUMARI JBI) guidelines was used to conduct the meta-analysis of this review. All data relevant to prevalence of HIV and STIs in male patients diagnosed with Monkeypox were extracted and exported into the JBI SUMARI. To assess point prevalence of HIV and STIs, we used the Freeman-Tukey-type arcsine square root transformation to stabilize the variances of the raw proportions. All estimates were weighted and pooled by the inverse variance using a fixed-effects model. We then used a random model to account for sampling variation and reported heterogeneity in effect size noted across studies in the fixed-effect model. The I2 test statistic and P values were used to measure the heterogeneity between studies. Values of I2 test statistic results were interpreted as follows: low (25%), moderate (50%) and high (75%). Results. Six studies from Spain and the UK met the inclusion criteria. These studies described a total of 541 male patients with monkeypox, 214 of them were positive for HIV and 255 had other STIs. Overall estimated prevalence of HIV and STIs was 40% (95% CI = 0.31%, 0.50%; ᵡ2 = 15) and 43% (95% CI = 25%, 61%; ᵡ2 = 118), respectively. Outcomes indicated moderate to high heterogeneity in the overall analyses. Conclusions. Approximately four in ten male patients affected in the 2022 Monkeypox outbreak had HIV and/or other STIs. Necessary public health measures should target male and female patients who are at risk of Monkeypox infection to prevent the transmission of serious infections such as HIV and other STIs.

Abstract WP26: Effectiveness of Tenecteplase versus Alteplase in Acute Ischemic Stroke Selected Subgroups of a Real-World-Data Set

Introduction: Tenecteplase is increasingly utilized as an alternative acute ischemic stroke (AIS) thrombolytic to Alteplase (tPA). Although many larger AIS trials have demonstrated the non-inferiority of TNK, Real World Data in many specific subgroups continue to be lacking. We studied the comparative effectiveness of AIS thrombolysis with TNK to tPA at our institution, focusing on currently understudied cohorts. Methods: We conducted a retrospective cohort analysis of AIS patients treated with thrombolysis within our health system. We utilized the Get With the Guidelines (GWTG) database to obtain basic demographic data. Additional variables and key outcomes (functional and radiographic) were abstracted independently by two authors from the electronic record. Disagreements were resolved by mutual consensus or a third investigator. An ordinal logistic regression model was used to assess the interventions' effectiveness, with the outcome being the modified Rankin Scale (mRS) score 90 days post-stroke. Subgroups included Age (&lt;60, 61-80, &gt;80), location of vessel occlusion (Large or Medium vessel), thrombolysis in the extended time window (beyond 4.5 hours), treatment via telestroke, and thrombectomy. Results: There were 500 consecutive AIS patients with complete outcome data. The mean age of the participants was 70.1 years, with 52.7% of patients being male. In the adjusted ordinal logistic regression analysis, the TNK group presented with 1.00 odds of a worse mRS score than the tPA group (95% CI 0.57-1.74). Subgroup regression analysis demonstrated no heterogeneity in effect size. Figure 1 is a Forest Plot demonstrating the Odds Ratio for each subgroup. Conclusions: It’s well-published that TNK is a comparable treatment for AIS and has demonstrated advantages. This analysis compared specific subgroups of real-world patients and showed no heterogeneity. This real-world subgroup analysis adds to the literature supporting the use of TNK for the treatment of AIS.

A review of the effects of active learning on high order thinking skills: a meta-analysis within islamic education

This study aims to ascertain the impact of the Active learning method on high-order thinking skills (HOTS) within the realm of Islamic education. Our primary contribution is the comprehensive meta-analysis of various preliminary and university educational studies. Using RStudio, we analyzed the differences in effect sizes, variations, and groups among studies. The findings indicate that the Active learning method significantly enhances HOTS, with the mixed learning method showing the most pronounced effect. We adopted a systematic approach, examining diverse learning methods like genre-based learning and blended learning model. Our research design entailed a meticulous meta-analysis of pre-existing literature rather than primary experimental or survey-based methods. However, we identified high heterogeneity in effect sizes as a limitation, suggesting the need for more nuanced studies in varied contexts. This research underscores educators' need to adapt learning strategies suited for specific educational levels, pointing towards a brighter horizon for tailored pedagogical interventions.

Digital Health Interventions for Quality Improvements in Chronic Kidney Disease Primary Care: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Chronic kidney disease (CKD) is a significant public health issue globally. The importance of its timely identification and early intervention is paramount. However, a systematic approach for early CKD management in the primary care setting is currently lacking, receiving less attention compared to upstream risk factors such as diabetes and hypertension. This oversight may lead to a failure in meeting quality-of-care indicators. Digital health interventions (DHIs), which leverage digital tools to enhance healthcare delivery, have shown effectiveness in managing chronic diseases and improving the quality, safety, and efficiency of primary care. Our research aimed to evaluate the effectiveness of DHIs in the care process, focusing on their reach, uptake, and feasibility. In this systematic review and meta-analysis, we searched PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and ClinicalTrials.gov for randomized controlled trials (RCTs) assessing DHIs' effectiveness in CKD patient care among adults in primary care settings. The search, conducted on 30 June 2023, included studies published in English from 1 January 2009. Screening was conducted using Covidence, adhering to Cochrane's guidelines for data extraction. We primarily evaluated changes in care processes (testing, documentation, medication use, etc.) and the use of renin-angiotensin-aldosterone system inhibitors (RAASi), referrals, among others. Multilevel meta-analysis was employed to address within-study clustering, and meta-regression analyzed the impact of study characteristics on heterogeneity in effect sizes. Clinical endpoints were recorded where available. Bias risk was assessed using the Cochrane Risk of Bias 2 tool. Data on reach, uptake, and feasibility were narratively summarized. The study is registered with PROSPERO (CRD42023449098). From 679 records, 12 RCTs were included in the narrative synthesis, and 6 studies (encompassing 7 trials) in the meta-analysis. The trials indicated a -0.85% change (95%CI, -5.82% to 4.11%) in the proportion of patients receiving desired care. This result showed considerable heterogeneity (I2 = 91.9%). One study characteristic (co-intervention, education) correlated with larger effects. Although including co-intervention in multivariable meta-regression was significant, it did not diminish heterogeneity. The reported reach varied and was not high, while the uptake was relatively high. Most studies did not explicitly address feasibility, though some statements implied its evaluation. The current literature on the impact of DHIs in community-based CKD care is limited. The studies suggest a non-significant effect of DHIs on enhancing CKD management in community settings, marked by significant heterogeneity. Future research should focus on rigorous, methodologically sound implementations to better assess the effectiveness of DHIs in the primary care management of CKD.

When is problem-oriented policing most effective? A systematic examination of heterogeneity in effect sizes for reducing crime and disorder

Abstract This article presents results from a systematic review and meta-analysis of problem-oriented policing (POP). The results show an overall 33.8% relative reduction in crime/disorder in treatment groups relative to controls, which adds to evidence that POP is an effective strategy that police leaders should adopt. There is, however, a great deal of variation in effect sizes, and moderator analyses were conducted to examine when POP may work best. Preliminary findings suggest POP may have larger impacts when responses are broader and involve more partner agencies/groups, when more of the agency is involved in the program, and when targeting property crime and disorder. Importantly, our findings also show that shallower implementations of POP still had significant impacts and suggest that POP should be implemented even if an agency cannot initially carry out in-depth problem-solving. Future research should supplement meta-analyses with narrative reviews to further identify what makes POP most effective.

AGING AND NUMERACY: A META-ANALYSIS

Abstract Numeracy, the ability to competently make use of numbers and numerical information, is a unique cognitive ability associated with diverse positive outcomes across the lifespan. Often included as a covariate in studies of cognitive aging, there is some scattered evidence of lower numeracy in older adults when compared to younger adults. Importantly, one longitudinal study found evidence of a quadratic decline in numeracy starting in later middle-age. The current study systematically reviews the literature on aging and numeracy as measured by one of three frequently implemented objective measures: the Lipkus numeracy scale (Lipkus et al., 2001), Weller et al.’s Rasch-based numeracy scale (2013), and the Berlin Numeracy Test (Cokely et al., 2012). Effect sizes were calculated from two types of studies: those including age as a categorical extreme group comparison variable or as a continuous variable from adult lifespan samples. Hedge’s g was computed as the effect size in the former studies and Pearson’s r was calculated as the effect size for the latter. For comparison across studies in a single random-effects model, Pearson’s r effect sizes were mathematically transformed into Hedge’s g’s. Type of sample (extreme group vs. adult lifespan) and age range were included in a second mixed-effects model to account for heterogeneity in effect sizes. Initial results show lower numeracy in older adults, but reduced effect size estimates in lifespan samples compared to those using extreme group comparisons. The implications for using linear estimates of effect size for the quadratic relationship between age and numeracy are discussed.

Effects of heat stress on feed intake, milk yield, milk composition, and feed efficiency in dairy cows: A meta-analysis

Heat stress compromises dairy production by decreasing feed intake and milk yield, and it may also alter milk composition and feed efficiency. However, little information is available for evaluating such effects across different levels of heat stress and cows enrolled in heat stress studies. The objectives of this study were to evaluate the effects of heat stress on dry matter intake (DMI), energy-corrected milk (ECM), milk composition, and feed efficiency (kg ECM/kg DMI) and to investigate the relationship between such effects and heat stress intervention and animal characteristics by using meta-analytical approaches. Data from 31 studies (34 trials) fulfilled the inclusion criteria and were used for analysis. Results showed that heat stress decreased DMI, ECM, and milk protein concentration, but did not alter milk fat concentration or feed efficiency. Meta-regression confirmed that such reductions in DMI and ECM were significantly associated with increasing temperature-humidity index (THI). Over the period of heat stress, for each unit increase in THI, DMI and ECM decreased by 4.13% and 3.25%, respectively, in mid-lactation cows. Regression models further revealed the existence of a strong interaction between THI and lactation stage, which partially explained the large heterogeneity in effect sizes of DMI and ECM. The results indicated a need for more research on the relationship between the effect of heat stress and animal characteristics. This study calls for the implementation of mitigation strategies in heat-stressed herds due to the substantial decrease in productivity.

Multi‐Ancestry Genetics for Alzheimer’s Disease: Alzheimer’s Disease Genetics Consortium

AbstractBackgroundAlzheimer’s disease (AD) affects individuals of all races and ethnicities, yet large‐scale genetic research to compare genetic makeups for risk or protection of AD between multi‐ancestry datasets is limited. The Alzheimer’s Disease Genetics Consortium (ADGC) assembled the largest multi‐ancestry dataset including 56,241 subjects from non‐Hispanic Whites (NHW), African Americans (AA), Hispanics (HI), and East Asians (EAS) to understand ancestral similarities and differences in genetic risk and protective variants for AD.MethodWe established a Steering Committee with 5 members, 4 main Workgroups including Primary Meta‐Analysis, Follow‐Up Analysis, Secondary Analysis, and Method Evaluation, and 3 affiliated Workgroups consisting of Phenotype Harmonization, Imputation Development, and genome‐wide association study (GWAS)/whole genome sequencing (WGS) Integration. A new computing infrastructure was developed for shared analytic space on Amazon Web Services (AWS), where all members from different institutes accessed to genetic and phenotypic data and conducted analysis under the master analysis plan with centrally developed pipelines and scripts. We conducted ancestry‐specific GWAS using single nucleotide polymorphisms (SNPs) for AD, cross‐ancestry meta‐analysis of 4 ancestry GWASs, fine‐mapping for allelic heterogeneity in known and novel loci for AD, and pathway analysis.ResultWe confirmed 12 known including APOE ɛ4 and ɛ2 variants and identified 2 novel loci for AD in cross‐ancestry meta‐analysis with P&lt;5.4×10−8. African and Asian ancestry subjects displayed greater heterogeneity in effect sizes and significant levels with the previously known AD loci for AD. Ancestry‐specific fine‐mapping indicated presence of potential distinct causal variants across different ancestry groups from multiple known AD loci. Two APOE alleles had greatest effect sizes among East Asians compared to others (EAS&gt;NHW&gt;AA&gt;HI), while we failed to observe significant association signals with AD in SHARPIN and TREM2 regions from African Americans. Of two novel loci, the association signal in the LRRC4C‐API5 region was contributed from all four ancestry groups; in contrast, the signal in the LHX5‐AS1‐RBM19 region was predominantly from Hispanics.ConclusionGenetic risk profiling in multi‐ancestry datasets provided unique opportunity to understand ancestry‐specific and cross‐ancestry genetic risk factors for AD. Further evaluation of these established and novel loci for AD by integrating GWAS and WGS data from ADSP is underway

Meta-analytical evidence that males prefer virgin females.

Males are often predicted to prefer virgin over non-virgin females because of the reduced risk of sperm competition. Does this prediction hold across studies? Our systematic meta-analysis of 138 studies, mainly conducted in invertebrates, confirms that males generally prefer virgin females. However, males preferred virgin females even in species with last male sperm precedence, suggesting that sperm competition alone does not drive male preferences. Furthermore, our results suggest that males may reject mated females even when no alternative exists. Preference for virgins is unlikely to influence female reproductive success since virginity cannot be selected for, but strong preference for virgin females could swamp or reinforce selection on other traits. Our results add to growing evidence that males are not indiscriminate in mating. However, given the unexplained heterogeneity in effect sizes, we urge caution in assuming that males will prefer virgins and recommend considering the natural context of mating decisions.

Effect of exercise interventions on hospital length of stay and admissions during cancer treatment: a systematic review and meta-analysis

ObjectiveTo assess the effect of participating in an exercise intervention compared with no exercise during cancer treatment on the duration and frequency of hospital admissions.DesignSystematic review and meta-analysis.Data sourcesMEDLINE, EMBASE,...