Silverman, Merav H.; Jedd, Kelly; Luciana, Monica
Behavioral responses to, and the neural processing of, rewards change dramatically during adolescence and may contribute to observed increases in risk-taking during this developmental period. Functional MRI (fMRI) studies suggest differences between adolescents and adults in neural activation during reward processing, but findings are contradictory, and effects have been found in non-predicted directions. The current study uses an activation likelihood estimation (ALE) approach for quantitative meta-analysis of functional neuroimaging studies to: 1) confirm the network of brain regions involved in adolescents’ reward processing, 2) identify regions involved in specific stages (anticipation, outcome) and valence (positive, negative) of reward processing, and 3) identify differences in activation likelihood between adolescent and adult reward-related brain activation. Results reveal a subcortical network of brain regions involved in adolescent reward processing similar to that found in adults with major hubs including the ventral and dorsal striatum, insula, and posterior cingulate cortex (PCC). Contrast analyses find that adolescents exhibit greater likelihood of activation in the insula while processing anticipation relative to outcome and greater likelihood of activation in the putamen and amygdala during outcome relative to anticipation. While processing positive compared to negative valence, adolescents show increased likelihood for activation in the posterior cingulate cortex (PCC) and ventral striatum. Contrasting adolescent reward processing with the existing ALE of adult reward processing (Liu et al., 2011) reveals increased likelihood for activation in limbic, frontolimbic, and striatal regions in adolescents compared with adults. Unlike adolescents, adults also activate executive control regions of the frontal and parietal lobes. These findings support hypothesized elevations in motivated activity during adolescence. PMID:26254587
JoAP 2007 N N The Good, the Bad, and the Unknown About Telecommuting : Meta-Analysis of Psychological Mediators and Individual Consequences Gavin, J...Work, nonwork, & family influences Shalley, C. E., Gilson, L. L., & Blum, T. C. ACMJ 2000 ? N Matching Creativity Requirements and the Work
Hägg, Sara; Ganna, Andrea; Van Der Laan, Sander W
) approach to assign variants to genes and to calculate gene-based P-values based on simulations. The VEGAS method was applied to each cohort separately before a gene-based meta-analysis was performed. In Stage 1, two known (FTO and TMEM18) and six novel (PEX2, MTFR2, SSFA2, IARS2, CEP295 and TXNDC12) loci...
Full Text Available Abstract Background The role of angiotensin-converting enzyme (ACE gene insertion/deletion (I/D polymorphism in modifying the response to treatment modalities in coronary artery disease is controversial. Methods PubMed was searched and a database of 58 studies with detailed information regarding ACE I/D polymorphism and response to treatment in coronary artery disease was created. Eligible studies were synthesized using meta-analysis methods, including cumulative meta-analysis. Heterogeneity and study quality issues were explored. Results Forty studies involved invasive treatments (coronary angioplasty or coronary artery by-pass grafting and 18 used conservative treatment options (including anti-hypertensive drugs, lipid lowering therapy and cardiac rehabilitation procedures. Clinical outcomes were investigated by 11 studies, while 47 studies focused on surrogate endpoints. The most studied outcome was the restenosis following coronary angioplasty (34 studies. Heterogeneity among studies (p ACE I/D polymorphism on the response to treatment for the rest outcomes (coronary events, endothelial dysfunction, left ventricular remodeling, progression/regression of atherosclerosis, individual studies showed significance; however, results were discrepant and inconsistent. Conclusion In view of available evidence, genetic testing of ACE I/D polymorphism prior to clinical decision making is not currently justified. The relation between ACE genetic variation and response to treatment in CAD remains an unresolved issue. The results of long-term and properly designed prospective studies hold the promise for pharmacogenetically tailored therapy in CAD.
Full Text Available Transcriptomics meta-analysis aims at re-using existing data to derive novel biological hypotheses, and is motivated by the public availability of a large number of independent studies. Current methods are based on breaking down studies into multiple comparisons between phenotypes (e.g. disease vs. healthy, based on the studies' experimental designs, followed by computing the overlap between the resulting differential expression signatures. While useful, in this methodology each study yields multiple independent phenotype comparisons, and connections are established not between studies, but rather between subsets of the studies corresponding to phenotype comparisons. We propose a rank-based statistical meta-analysis framework that establishes global connections between transcriptomics studies without breaking down studies into sets of phenotype comparisons. By using a rank product method, our framework extracts global features from each study, corresponding to genes that are consistently among the most expressed or differentially expressed genes in that study. Those features are then statistically modelled via a term-frequency inverse-document frequency (TF-IDF model, which is then used for connecting studies. Our framework is fast and parameter-free; when applied to large collections of Homo sapiens and Streptococcus pneumoniae transcriptomics studies, it performs better than similarity-based approaches in retrieving related studies, using a Medical Subject Headings gold standard. Finally, we highlight via case studies how the framework can be used to derive novel biological hypotheses regarding related studies and the genes that drive those connections. Our proposed statistical framework shows that it is possible to perform a meta-analysis of transcriptomics studies with arbitrary experimental designs by deriving global expression features rather than decomposing studies into multiple phenotype comparisons.
Guida, Pietro; Mastro, Florinda; Scrascia, Giuseppe; Whitlock, Richard; Paparella, Domenico
A systematic review of the European System for Cardiac Operative Risk Evaluation (euroSCORE) II performance for prediction of operative mortality after cardiac surgery has not been performed. We conducted a meta-analysis of studies based on the predictive accuracy of the euroSCORE II. We searched the Embase and PubMed databases for all English-only articles reporting performance characteristics of the euroSCORE II. The area under the receiver operating characteristic curve, the observed/expected mortality ratio, and observed-expected mortality difference with their 95% confidence intervals were analyzed. Twenty-two articles were selected, including 145,592 procedures. Operative mortality occurred in 4293 (2.95%), whereas the expected events according to euroSCORE II were 4802 (3.30%). Meta-analysis of these studies provided an area under the receiver operating characteristic curve of 0.792 (95% confidence interval, 0.773-0.811), an estimated observed/expected ratio of 1.019 (95% confidence interval, 0.899-1.139), and observed-expected difference of 0.125 (95% confidence interval, -0.269 to 0.519). Statistical heterogeneity was detected among retrospective studies including less recent procedures. Subgroups analysis confirmed the robustness of combined estimates for isolated valve procedures and those combined with revascularization surgery. A significant overestimation of the euroSCORE II with an observed/expected ratio of 0.829 (95% confidence interval, 0.677-0.982) was observed in isolated coronary artery bypass grafting and a slight underestimation of predictions in high-risk patients (observed/expected ratio 1.253 and observed-expected difference 1.859). Despite the heterogeneity, the results from this meta-analysis show a good overall performance of the euroSCORE II in terms of discrimination and accuracy of model predictions for operative mortality. Validation of the euroSCORE II in prospective populations needs to be further studied for a continuous
Wen, Song; Zhou, Wei; Li, Chun-ming; Hu, Juan; Hu, Xiao-ming; Chen, Ping; Shao, Guo-liang; Guo, Wu-hua
Despite the large number of published papers analyzing the prognostic role of Ki-67 in NSCLC, it is still not considered an established factor for routine use in clinical practice. The present meta-analysis summarizes and analyses the associations between Ki-67 expression and clinical outcome in NSCLC patients. PubMed, Cochrane, and Embase databases were searched systematically using identical search strategies. The impacts of Ki-67 expression on survival in patients with NSCLC and NSCLC subtypes were evaluated. Furthermore, the association between Ki-67 expression and the clinicopathological features of NSCLC were evaluated. In total, 32 studies from 30 articles met the inclusion criteria, involving 5600 patients. Meta-analysis results suggested that high Ki-67 expression was negatively associated with overall survival (OS; HR = 1.59, 95 % CI 1.35-1.88, P < 0.001) and disease-free survival (DFS; HR = 2.21, 95 % CI 1.43-3.42, P < 0.001) in NSCLC patients. Analysis of the different subgroups of NSCLC suggested that the negative association between high Ki-67 expression and OS and DFS in Asian NSCLC patients was stronger than that in non-Asian NSCLC patients, particularly in early-stage (Stage I-II) adenocarcinoma (ADC) patients. Additionally, while high expression was more common in males, smokers, and those with poorer differentiation, there was no correlation between high Ki-67 expression and age or lymph node status. Importantly, significant correlations between high Ki-67 expression and clinicopathological features (males, higher tumor stage, poor differentiation) were seen only in Asian NSCLC patients. The present meta-analysis indicated that elevated Ki-67 expression was associated with a poorer outcome in NSCLC patients, particularly in early-stage Asian ADC patients. Studies with larger numbers of patients are needed to validate our findings. The online version of this article (doi:10.1186/s12885-015-1524-2) contains supplementary material, which is
Dimou, Niki L; Pantavou, Katerina G; Braliou, Georgia G; Bagos, Pantelis G
Multivariate meta-analysis of genetic association studies and genome-wide association studies has received a remarkable attention as it improves the precision of the analysis. Here, we review, summarize and present in a unified framework methods for multivariate meta-analysis of genetic association studies and genome-wide association studies. Starting with the statistical methods used for robust analysis and genetic model selection, we present in brief univariate methods for meta-analysis and we then scrutinize multivariate methodologies. Multivariate models of meta-analysis for a single gene-disease association studies, including models for haplotype association studies, multiple linked polymorphisms and multiple outcomes are discussed. The popular Mendelian randomization approach and special cases of meta-analysis addressing issues such as the assumption of the mode of inheritance, deviation from Hardy-Weinberg Equilibrium and gene-environment interactions are also presented. All available methods are enriched with practical applications and methodologies that could be developed in the future are discussed. Links for all available software implementing multivariate meta-analysis methods are also provided.
Manassis, Katharina; Lee, Trevor Changgun; Bennett, Kathryn; Zhao, Xiu Yan; Mendlowitz, Sandra; Duda, Stephanie; Saini, Michael; Wilansky, Pamela; Baer, Susan; Barrett, Paula; Bodden, Denise; Cobham, Vanessa E; Dadds, Mark R; Flannery-Schroeder, Ellen; Ginsburg, Golda; Heyne, David; Hudson, Jennifer L; Kendall, Philip C; Liber, Juliette; Masia-Warner, Carrie; Nauta, Maaike H; Rapee, Ronald M; Silverman, Wendy; Siqueland, Lynne; Spence, Susan H; Utens, Elisabeth; Wood, Jeffrey J
Meta-analytic studies have not confirmed that involving parents in cognitive behavior therapy (CBT) for anxious children is therapeutically beneficial. There is also great heterogeneity in the type of parental involvement included. We investigated parental involvement focused on contingency management (CM) and transfer of control (TC) as a potential outcome moderator using a meta-analysis with individual patient data. Investigators of randomized controlled trials (RCTs) of CBT for anxious children, identified systematically, were invited to submit their data. Conditions in each RCT were coded based on type of parental involvement in CBT (i.e., low involvement, active involvement without emphasis on CM or TC, active involvement with emphasis on CM or TC). Treatment outcomes were compared using a 1-stage meta-analysis. All cases involved in active treatment (894 of 1,618) were included for subgroup analyses. Across all CBT groups, means of clinical severity, anxiety, and internalizing symptoms significantly decreased posttreatment and were comparable across groups. The group without emphasis on CM or TC showed a higher proportion with posttreatment anxiety diagnoses than the low-involvement group. Between posttreatment and 1-year follow-up, the proportion with anxiety diagnoses significantly decreased in CBT with active parental involvement with emphasis on CM or TC, whereas treatment gains were merely maintained in the other 2 groups. CBT for anxious children is an effective treatment with or without active parental involvement. However, CBT with active parental involvement emphasizing CM or TC may support long-term maintenance of treatment gains. RESULTS should be replicated as additional RCTs are published.
Liu, Fan; Chen, Yan; Zhu, Gu; Hysi, Pirro G; Wu, Sijie; Adhikari, Kaustubh; Breslin, Krystal; Pospiech, Ewelina; Hamer, Merel A; Peng, Fuduan; Muralidharan, Charanya; Acuna-Alonzo, Victor; Canizales-Quinteros, Samuel; Bedoya, Gabriel; Gallo, Carla; Poletti, Giovanni; Rothhammer, Francisco; Bortolini, Maria Catira; Gonzalez-Jose, Rolando; Zeng, Changqing; Xu, Shuhua; Jin, Li; Uitterlinden, André G; Ikram, M Arfan; van Duijn, Cornelia M; Nijsten, Tamar; Walsh, Susan; Branicki, Wojciech; Wang, Sijia; Ruiz-Linares, Andrés; Spector, Timothy D; Martin, Nicholas G; Medland, Sarah E; Kayser, Manfred
Shape variation of human head hair shows striking variation within and between human populations, while its genetic basis is far from being understood. We performed a series of genome-wide association studies (GWASs) and replication studies in a total of 28 964 subjects from 9 cohorts from multiple geographic origins. A meta-analysis of three European GWASs identified 8 novel loci (1p36.23 ERRFI1/SLC45A1, 1p36.22 PEX14, 1p36.13 PADI3, 2p13.3 TGFA, 11p14.1 LGR4, 12q13.13 HOXC13, 17q21.2 KRTAP, and 20q13.33 PTK6), and confirmed 4 previously known ones (1q21.3 TCHH/TCHHL1/LCE3E, 2q35 WNT10A, 4q21.21 FRAS1, and 10p14 LINC00708/GATA3), all showing genome-wide significant association with hair shape (P 5e-8). All except one (1p36.22 PEX14) were replicated with nominal significance in at least one of the 6 additional cohorts of European, Native American and East Asian origins. Three additional previously known genes (EDAR, OFCC1, and PRSS53) were confirmed at the nominal significance level. A multivariable regression model revealed that 14 SNPs from different genes significantly and independently contribute to hair shape variation, reaching a cross-validated AUC value of 0.66 (95% CI: 0.62-0.70) and an AUC value of 0.64 in an independent validation cohort, providing an improved accuracy compared with a previous model. Prediction outcomes of 2504 individuals from a multiethnic sample were largely consistent with general knowledge on the global distribution of hair shape variation. Our study thus delivers target genes and DNA variants for future functional studies to further evaluate the molecular basis of hair shape in humans. © The Author(s) 2017. Published by Oxford University Press.
Liu, Fan; Chen, Yan; Zhu, Gu; Hysi, Pirro G; Wu, Sijie; Adhikari, Kaustubh; Breslin, Krystal; Pośpiech, Ewelina; Hamer, Merel A; Peng, Fuduan; Muralidharan, Charanya; Acuna-Alonzo, Victor; Canizales-Quinteros, Samuel; Bedoya, Gabriel; Gallo, Carla; Poletti, Giovanni; Rothhammer, Francisco; Bortolini, Maria Catira; Gonzalez-Jose, Rolando; Zeng, Changqing; Xu, Shuhua; Jin, Li; Uitterlinden, André G; Ikram, M Arfan; van Duijn, Cornelia M; Nijsten, Tamar; Walsh, Susan; Branicki, Wojciech; Wang, Sijia; Ruiz-Linares, Andrés; Spector, Timothy D; Martin, Nicholas G; Medland, Sarah E; Kayser, Manfred
Abstract Shape variation of human head hair shows striking variation within and between human populations, while its genetic basis is far from being understood. We performed a series of genome-wide association studies (GWASs) and replication studies in a total of 28 964 subjects from 9 cohorts from multiple geographic origins. A meta-analysis of three European GWASs identified 8 novel loci (1p36.23 ERRFI1/SLC45A1, 1p36.22 PEX14, 1p36.13 PADI3, 2p13.3 TGFA, 11p14.1 LGR4, 12q13.13 HOXC13, 17q21.2 KRTAP, and 20q13.33 PTK6), and confirmed 4 previously known ones (1q21.3 TCHH/TCHHL1/LCE3E, 2q35 WNT10A, 4q21.21 FRAS1, and 10p14 LINC00708/GATA3), all showing genome-wide significant association with hair shape (P < 5e-8). All except one (1p36.22 PEX14) were replicated with nominal significance in at least one of the 6 additional cohorts of European, Native American and East Asian origins. Three additional previously known genes (EDAR, OFCC1, and PRSS53) were confirmed at the nominal significance level. A multivariable regression model revealed that 14 SNPs from different genes significantly and independently contribute to hair shape variation, reaching a cross-validated AUC value of 0.66 (95% CI: 0.62–0.70) and an AUC value of 0.64 in an independent validation cohort, providing an improved accuracy compared with a previous model. Prediction outcomes of 2504 individuals from a multiethnic sample were largely consistent with general knowledge on the global distribution of hair shape variation. Our study thus delivers target genes and DNA variants for future functional studies to further evaluate the molecular basis of hair shape in humans. PMID:29220522
Stone, Carol Leth
Long term studies of advance organizers (AO) were analyzed with Glass's meta-analysis technique. AO's were defined as bridges from reader's previous knowledge to what is to be learned. The results were compared with predictions from Ausubel's model of assimilative learning. The results of the study indicated that advance organizers were associated…
Stone, Carol Leth
Twenty-nine reports yielding 112 studies were analyzed with Glass's meta-analysis technique, and results were compared with predictions from Ausubel's model of assimilative learning. Overall, advance organizers were shown to be associated with increased learning and retention of material to be learned. (Author)
Deng, Wei Q; Asma, Senay; Paré, Guillaume
Meta-analysis is a commonly used approach to increase the sample size for genome-wide association searches when individual studies are otherwise underpowered. Here, we present a meta-analysis procedure to estimate the heterogeneity of the quantitative trait variance attributable to genetic variants using Levene's test without needing to exchange individual-level data. The meta-analysis of Levene's test offers the opportunity to combine the considerable sample size of a genome-wide meta-analysis to identify the genetic basis of phenotypic variability and to prioritize single-nucleotide polymorphisms (SNPs) for gene–gene and gene–environment interactions. The use of Levene's test has several advantages, including robustness to departure from the normality assumption, freedom from the influence of the main effects of SNPs, and no assumption of an additive genetic model. We conducted a meta-analysis of the log-transformed body mass index of 5892 individuals and identified a variant with a highly suggestive Levene's test P-value of 4.28E-06 near the NEGR1 locus known to be associated with extreme obesity. PMID:23921533
Full Text Available BACKGROUND: Many epidemiological studies have found a positive association between periodontal disease (PD and the risk of preeclampsia, but the magnitude of this association varies and independent studies have reported conflicting findings. We performed a meta-analysis to ascertain the relationship between PD and preeclampsia. METHODS: The PubMed database was searched up to January 12, 2013, for relevant observational studies on an association between PD and the risk of preeclampsia. Data were extracted and analyzed independently by two authors. The meta-analysis was performed using comprehensive meta-analysis software. RESULTS: Thirteen observational case-control studies and two cohort studies, involving 1089 preeclampsia patients, were identified. Based on a random-effects meta-analysis, a significant association between PD and preeclampsia was identified (odds ratio = 2.79, 95% confidence interval CI, 2.01-3.01, P<0.0001. CONCLUSIONS: Although the causality remains unclear, the association between PD and preeclampsia may reflect the induction of PD by the preeclamptic state, or it may be part of an overall exaggerated inflammatory response to pregnancy. Larger randomized controlled trials with preeclampsia as the primary outcome and pathophysiological studies are required to explore causality and to dissect the biological mechanisms involved.
Ning, Yu; Cheng, Yun J; Liu, Li J; Sara, Jaskanwal D S; Cao, Zhi Y; Zheng, Wei P; Zhang, Tian S; Han, Hui J; Yang, Zhen Y; Zhang, Yi; Wang, Fei L; Pan, Rui Y; Huang, Jie L; Wu, Ling L; Zhang, Ming; Wei, Yong X
Whether hypothyroidism is an independent risk factor for cardiovascular events is still disputed. We aimed to assess the association between hypothyroidism and risks of cardiovascular events and mortality. We searched PubMed and Embase from inception to 29 February 2016. Cohort studies were included with no restriction of hypothyroid states. Priori main outcomes were ischemic heart disease (IHD), cardiac mortality, cardiovascular mortality, and all-cause mortality. Fifty-five cohort studies involving 1,898,314 participants were identified. Patients with hypothyroidism, compared with euthyroidism, experienced higher risks of IHD (relative risk (RR): 1.13; 95% confidence interval (CI): 1.01-1.26), myocardial infarction (MI) (RR: 1.15; 95% CI: 1.05-1.25), cardiac mortality (RR: 1.96; 95% CI: 1.38-2.80), and all-cause mortality (RR: 1.25; 95% CI: 1.13-1.39); subclinical hypothyroidism (SCH; especially with thyrotropin level ≥10 mIU/L) was also associated with higher risks of IHD and cardiac mortality. Moreover, cardiac patients with hypothyroidism, compared with those with euthyroidism, experienced higher risks of cardiac mortality (RR: 2.22; 95% CI: 1.28-3.83) and all-cause mortality (RR: 1.51; 95% CI: 1.26-1.81). Hypothyroidism is a risk factor for IHD and cardiac mortality. Hypothyroidism is associated with higher risks of cardiac mortality and all-cause mortality compared with euthyroidism in the general public or in patients with cardiac disease.
Nikolakopoulou, Adriani; Mavridis, Dimitris; Furukawa, Toshi A; Cipriani, Andrea; Tricco, Andrea C; Straus, Sharon E; Siontis, George C M; Egger, Matthias; Salanti, Georgia
To examine whether the continuous updating of networks of prospectively planned randomised controlled trials (RCTs) ("living" network meta-analysis) provides strong evidence against the null hypothesis in comparative effectiveness of medical interventions earlier than the updating of conventional, pairwise meta-analysis. Empirical study of the accumulating evidence about the comparative effectiveness of clinical interventions. Database of network meta-analyses of RCTs identified through searches of Medline, Embase, and the Cochrane Database of Systematic Reviews until 14 April 2015. Network meta-analyses published after January 2012 that compared at least five treatments and included at least 20 RCTs. Clinical experts were asked to identify in each network the treatment comparison of greatest clinical interest. Comparisons were excluded for which direct and indirect evidence disagreed, based on side, or node, splitting test (Pmeta-analyses were performed for each selected comparison. Monitoring boundaries of statistical significance were constructed and the evidence against the null hypothesis was considered to be strong when the monitoring boundaries were crossed. A significance level was defined as α=5%, power of 90% (β=10%), and an anticipated treatment effect to detect equal to the final estimate from the network meta-analysis. The frequency and time to strong evidence was compared against the null hypothesis between pairwise and network meta-analyses. 49 comparisons of interest from 44 networks were included; most (n=39, 80%) were between active drugs, mainly from the specialties of cardiology, endocrinology, psychiatry, and rheumatology. 29 comparisons were informed by both direct and indirect evidence (59%), 13 by indirect evidence (27%), and 7 by direct evidence (14%). Both network and pairwise meta-analysis provided strong evidence against the null hypothesis for seven comparisons, but for an additional 10 comparisons only network meta-analysis provided
Stetter, Friedhelm; Kupper, Sirko
Autogenic training (AT) is a self-relaxation procedure by which a psychophysiological determined relaxation response is elicited. A meta-analysis was performed to evaluate the clinical effectiveness of AT. Seventy-three controlled outcome studies were found (published 1952-99). Sixty studies (35 randomized controlled trials [RCT]) qualified for inclusion in the meta-analysis. Medium-to-large effect sizes (ES) occurred for pre-post comparisons of disease-specific AT-effects, with the RCTs showing larger ES. When AT was compared to real control conditions, medium ES were found. Comparisons of AT versus other psychological treatment mostly resulted in no effects or small negative ES. This pattern of results was stable at follow-up. Unspecific AT-effects (i.e., effects on mood, cognitive performance, quality of life, and physiological variables) tended to be even larger than main effects. Separate meta-analyses for different disorders revealed a significant reduction of the heterogeneity of ES. Positive effects (medium range) of AT and of AT versus control in the meta-analysis of at least 3 studies were found for tension headache/migraine, mild-to-moderate essential hypertension, coronary heart disease, asthma bronchiale, somatoform pain disorder (unspecified type), Raynaud's disease, anxiety disorders, mild-to-moderate depression/dysthymia, and functional sleep disorders.
Full Text Available BACKGROUND: Many epidemiological studies have found a positive association between periodontal disease (PD and risk of chronic obstructive pulmonary disease (COPD, but this association is varied and even contradictory among studies. We performed a meta-analysis to ascertain the relationship between PD and COPD. METHODS: PubMed and Embase database were searched up to January 10, 2012, for relevant observational studies on the association between PD and risk of COPD. Data from the studies selected were extracted and analyzed independently by two authors. The meta-analysis was performed using the Comprehensive Meta-Analysis software. RESULTS: Fourteen observational studies (one nested case-control, eight case-control, and five cross-sectional involving 3,988 COPD patients were yielded. Based on random-effects meta-analysis, a significant association between PD and COPD was identified (odds ratio = 2.08, 95% confidence interval = 1.48-2.91; P<0.001, with sensitivity analysis showing that the result was robust. Subgroups analyses according to study design, ethnicity, assessment of PD/COPD, and adjusted/unadjusted odds ratios also revealed a significant association. Publication bias was detected. CONCLUSIONS: Based on current evidence, PD is a significant and independent risk factor of COPD. However, whether a causal relationships exists remains unclear. Morever, we suggest performing randomized controlled trails to explore whether periodontal interventions are beneficial in regulating COPD pathogenesis and progression.
Nikolakopoulou, Adriani; Mavridis, Dimitris; Furukawa, Toshi A; Cipriani, Andrea; Tricco, Andrea C; Straus, Sharon E; Siontis, George C M; Egger, Matthias
Abstract Objective To examine whether the continuous updating of networks of prospectively planned randomised controlled trials (RCTs) (“living” network meta-analysis) provides strong evidence against the null hypothesis in comparative effectiveness of medical interventions earlier than the updating of conventional, pairwise meta-analysis. Design Empirical study of the accumulating evidence about the comparative effectiveness of clinical interventions. Data sources Database of network meta-analyses of RCTs identified through searches of Medline, Embase, and the Cochrane Database of Systematic Reviews until 14 April 2015. Eligibility criteria for study selection Network meta-analyses published after January 2012 that compared at least five treatments and included at least 20 RCTs. Clinical experts were asked to identify in each network the treatment comparison of greatest clinical interest. Comparisons were excluded for which direct and indirect evidence disagreed, based on side, or node, splitting test (Pmeta-analysis. The frequency and time to strong evidence was compared against the null hypothesis between pairwise and network meta-analyses. Results 49 comparisons of interest from 44 networks were included; most (n=39, 80%) were between active drugs, mainly from the specialties of cardiology, endocrinology, psychiatry, and rheumatology. 29 comparisons were informed by both direct and indirect evidence (59%), 13 by indirect evidence (27%), and 7 by direct evidence (14%). Both network and pairwise meta-analysis provided strong evidence against the null hypothesis for seven comparisons, but for an additional 10 comparisons only network meta-analysis provided strong evidence against the null hypothesis (P=0.002). The median time to strong evidence against the null hypothesis was 19 years with living network meta-analysis and 23 years with living pairwise meta-analysis (hazard ratio 2.78, 95% confidence interval 1.00 to 7.72, P=0.05). Studies directly comparing
Tang, D W; Fellows, L K; Small, D M; Dagher, A
In healthy individuals, food cues can trigger hunger and feeding behavior. Likewise, smoking cues can trigger craving and relapse in smokers. Brain imaging studies report that structures involved in appetitive behaviors and reward, notably the insula, striatum, amygdala and orbital frontal cortex, tend to be activated by both visual food and smoking cues. Here, by carrying out a meta-analysis of human neuro-imaging studies, we investigate the neural network activated by: 1) food versus neutral cues (14 studies, 142 foci) 2) smoking versus neutral cues (15 studies, 176 foci) 3) smoking versus neutral cues when correlated with craving scores (7 studies, 108 foci). PubMed was used to identify cue-reactivity imaging studies that compared brain response to visual food or smoking cues to neutral cues. Fourteen articles were identified for the food meta-analysis and fifteen articles were identified for the smoking meta-analysis. Six articles were identified for the smoking cue correlated with craving analysis. Meta-analyses were carried out using activation likelihood estimation. Food cues were associated with increased blood oxygen level dependent (BOLD) response in the left amygdala, bilateral insula, bilateral orbital frontal cortex, and striatum. Smoking cues were associated with increased BOLD signal in the same areas, with the exception of the insula. However, the smoking meta-analysis of brain maps correlating cue-reactivity with subjective craving did identify the insula, suggesting that insula activation is only found when craving levels are high. The brain areas identified here are involved in learning, memory and motivation, and their cue-induced activity is an index of the incentive salience of the cues. Using meta-analytic techniques to combine a series of studies, we found that food and smoking cues activate comparable brain networks. There is significant overlap in brain regions responding to conditioned cues associated with natural and drug rewards
Ma, Xin; Shen, Jianping; Krenn, Huilan Y.; Hu, Shanshan; Yuan, Jing
This meta-analysis examined the relationship between learning outcomes of children and educational involvement of parents during a unique period of early childhood education and early elementary education based on 100 independent effect sizes from 46 studies. Learning outcomes are academic achievement, and frameworks of parental involvement…
Full Text Available In a meta-analysis with multiple end points of interests that are correlated between or within studies, multivariate approach to meta-analysis has a potential to produce more precise estimates of effects by exploiting the correlation structure between end points. However, under random-effects assumption the multivariate estimation is more complex (as it involves estimation of more parameters simultaneously than univariate estimation, and sometimes can produce unrealistic parameter estimates. Usefulness of multivariate approach to meta-analysis of the effects of a genetic variant on two or more correlated traits is not well understood in the area of genetic association studies. In such studies, genetic variants are expected to roughly maintain Hardy-Weinberg equilibrium within studies, and also their effects on complex traits are generally very small to modest and could be heterogeneous across studies for genuine reasons. We carried out extensive simulation to explore the comparative performance of multivariate approach with most commonly used univariate inverse-variance weighted approach under random-effects assumption in various realistic meta-analytic scenarios of genetic association studies of correlated end points. We evaluated the performance with respect to relative mean bias percentage, and root mean square error (RMSE of the estimate and coverage probability of corresponding 95% confidence interval of the effect for each end point. Our simulation results suggest that multivariate approach performs similarly or better than univariate method when correlations between end points within or between studies are at least moderate and between-study variation is similar or larger than average within-study variation for meta-analyses of 10 or more genetic studies. Multivariate approach produces estimates with smaller bias and RMSE especially for the end point that has randomly or informatively missing summary data in some individual studies, when
Lum, Jarrad A. G.; Powell, Martine; Timms, Lydia; Snow, Pamela
Purpose: In this review article, meta-analysis was used to summarize research investigating language skills in maltreated children. Method: A systematic search of published studies was undertaken. Studies were included in the meta-analysis if they investigated language skills in groups comprising maltreated and nonmaltreated children. Studies were…
Mila, A L; Ngugi, H K
Bayesian statistical methods are used for meta-analysis in many disciplines, including medicine, molecular biology, and engineering, but have not yet been applied for quantitative synthesis of plant pathology studies. In this paper, we illustrate the key concepts of Bayesian statistics and outline the differences between Bayesian and classical (frequentist) methods in the way parameters describing population attributes are considered. We then describe a Bayesian approach to meta-analysis and present a plant pathological example based on studies evaluating the efficacy of plant protection products that induce systemic acquired resistance for the management of fire blight of apple. In a simple random-effects model assuming a normal distribution of effect sizes and no prior information (i.e., a noninformative prior), the results of the Bayesian meta-analysis are similar to those obtained with classical methods. Implementing the same model with a Student's t distribution and a noninformative prior for the effect sizes, instead of a normal distribution, yields similar results for all but acibenzolar-S-methyl (Actigard) which was evaluated only in seven studies in this example. Whereas both the classical (P = 0.28) and the Bayesian analysis with a noninformative prior (95% credibility interval [CRI] for the log response ratio: -0.63 to 0.08) indicate a nonsignificant effect for Actigard, specifying a t distribution resulted in a significant, albeit variable, effect for this product (CRI: -0.73 to -0.10). These results confirm the sensitivity of the analytical outcome (i.e., the posterior distribution) to the choice of prior in Bayesian meta-analyses involving a limited number of studies. We review some pertinent literature on more advanced topics, including modeling of among-study heterogeneity, publication bias, analyses involving a limited number of studies, and methods for dealing with missing data, and show how these issues can be approached in a Bayesian framework
Balan, Bipin; Marra, Francesco Paolo; Caruso, Tiziano; Martinelli, Federico
RNA-Seq analysis is a strong tool to gain insight into the molecular responses to biotic stresses in plants. The objective of this work is to identify specific and common molecular responses between different transcriptomic data related to fungi, virus and bacteria attacks in Malus x domestica. We analyzed seven transcriptomic datasets in Malus x domestica divided in responses to fungal pathogens, virus (Apple Stem Grooving Virus) and bacteria (Erwinia amylovora). Data were dissected using an integrated approach of pathway- and gene- set enrichment analysis, Mapman visualization tool, gene ontology analysis and inferred protein-protein interaction network. Our meta-analysis revealed that the bacterial infection enhanced specifically genes involved in sugar alcohol metabolism. Brassinosteroids were upregulated by fungal pathogens while ethylene was highly affected by Erwinia amylovora. Gibberellins and jasmonates were strongly repressed by fungal and viral infections. The protein-protein interaction network highlighted the role of WRKYs in responses to the studied pathogens. In summary, our meta-analysis provides a better understanding of the Malus X domestica transcriptome responses to different biotic stress conditions; we anticipate that these insights will assist in the development of genetic resistance and acute therapeutic strategies. This work would be an example for next meta-analysis works aiming at identifying specific common molecular features linked with biotic stress responses in other specialty crops.
Qiu, Qihong; Zhang, Fuping; Zhu, Wenjun; Wu, Juan; Liang, Min
Copper (Cu) is an important trace element involved in oxidative stress, which is associated with the onset and progression of diabetes mellitus (DM). However, clinical studies comparing plasma or serum Cu levels in patients with DM and in healthy individuals report conflicting findings. Therefore, in this meta-analysis, we analyzed the circulating levels of Cu associated with DM (including type 1 diabetes mellitus [T1DM] and type 2 diabetes mellitus [T2DM]). We searched the articles indexed in PubMed, OVID, and Cochrane databases, published through January 2016 and meeting our predefined criteria. Requisite data were extracted, and a random-effect model or a fixed-effect model was used to conduct the meta-analysis. Fifteen eligible studies involving a total of 1079 DM patients and 561 healthy controls were identified. Overall, the DM patients showed higher Cu levels than the healthy controls (plasma Cu mean difference [MD] = 1.69 μmol/L, p 1; serum Cu MD = 4.06 μmol/L, p = 0.005; plasma and serum Cu MD = 2.67 μmol/L, p = 0.006). Stratification based on the type of diabetes also indicated higher levels of Cu in the plasma and serum of DM patients than in healthy controls, respectively. Stratification of DM patients associated with and without complications also revealed similar results. This meta-analysis suggests that DM patients carried higher levels of Cu than healthy individuals. However, international cohort studies are needed to corroborate our findings.
Diana Sarokhani; Ali Delpisheh; Yousef Veisani; Mohamad Taher Sarokhani; Rohollah Esmaeli Manesh; Kourosh Sayehmiri
Introduction. Depression is one of the four major diseases in the world and is the most common cause of disability from diseases. The aim of this study is to estimate the prevalence of depression among Iranian university students using meta-analysis method. Materials and Methods. Keyword depression was searched in electronic databases such as PubMed, Scopus, MAGIran, Medlib, and SID. Data was analyzed using meta-analysis (random-effects model). Heterogeneity of studies was assessed using ...
Martorell-Marugan, Jordi; Toro-Dominguez, Daniel; Alarcon-Riquelme, Marta E; Carmona-Saez, Pedro
Genetic association studies (GAS) aims to evaluate the association between genetic variants and phenotypes. In the last few years, the number of this type of study has increased exponentially, but the results are not always reproducible due to experimental designs, low sample sizes and other methodological errors. In this field, meta-analysis techniques are becoming very popular tools to combine results across studies to increase statistical power and to resolve discrepancies in genetic association studies. A meta-analysis summarizes research findings, increases statistical power and enables the identification of genuine associations between genotypes and phenotypes. Meta-analysis techniques are increasingly used in GAS, but it is also increasing the amount of published meta-analysis containing different errors. Although there are several software packages that implement meta-analysis, none of them are specifically designed for genetic association studies and in most cases their use requires advanced programming or scripting expertise. We have developed MetaGenyo, a web tool for meta-analysis in GAS. MetaGenyo implements a complete and comprehensive workflow that can be executed in an easy-to-use environment without programming knowledge. MetaGenyo has been developed to guide users through the main steps of a GAS meta-analysis, covering Hardy-Weinberg test, statistical association for different genetic models, analysis of heterogeneity, testing for publication bias, subgroup analysis and robustness testing of the results. MetaGenyo is a useful tool to conduct comprehensive genetic association meta-analysis. The application is freely available at http://bioinfo.genyo.es/metagenyo/ .
Wu, Q; Liu, B; Tonmoy, S
This meta-analysis pooled results from 23 qualifying individual cohort studies and found that depression was significantly associated with an increased risk of fractures and bone loss. The association between depression and risk of fracture remains controversial. We conducted a comprehensive meta-analysis to examine the effect of depression on the risk of osteoporotic fractures and bone loss. We searched databases and reviewed citations in relevant articles for eligible cohort studies. Two investigators independently conducted study selection, appraisal, and data abstraction through the use of a standardized protocol. Random effect models were used for meta-analysis. Cochrane Q and I 2 statistics were used to assess heterogeneity. Funnel plots and rank correlation tests were used to evaluate publication bias. Twenty-three studies were included for meta-analysis. In studies that reported hazard ratio (HR) as the outcome (nine studies [n = 309,862]), depression was associated with 26% increase in fracture risk (HR = 1.26, 95% CI, 1.10-1.43, p meta-analysis having modified inclusion criteria and in different subgroup analyses as well. Significant heterogeneity was observed in the meta-analysis; however, no significant publication bias was detected. Depression is associated with a significant increased risk in fracture and bone loss. Effective prevention may decrease such risk.
Fusar-Poli, Paolo; Howes, Oliver; Bechdolf, Andreas; Borgwardt, Stefan
Background Although early interventions in individuals with bipolar disorder may reduce the associated personal and economic burden, the neurobiologic markers of enhanced risk are unknown. Methods Neuroimaging studies involving individuals at enhanced genetic risk for bipolar disorder (HR) were included in a systematic review. We then performed a region of interest (ROI) analysis and a whole-brain meta-analysis combined with a formal effect-sizes meta-analysis in a subset of studies. Results There were 37 studies included in our systematic review. The overall sample for the systematic review included 1258 controls and 996 HR individuals. No significant differences were detected between HR individuals and controls in the selected ROIs: striatum, amygdala, hippocampus, pituitary and frontal lobe. The HR group showed increased grey matter volume compared with patients with established bipolar disorder. The HR individuals showed increased neural response in the left superior frontal gyrus, medial frontal gyrus and left insula compared with controls, independent from the functional magnetic resonance imaging task used. There were no publication biases. Sensitivity analysis confirmed the robustness of these results. Limitations As the included studies were cross-sectional, it remains to be determined whether the observed neurofunctional and structural alterations represent risk factors that can be clinically used in preventive interventions for prodromal bipolar disorder. Conclusion Accumulating structural and functional imaging evidence supports the existence of neurobiologic trait abnormalities in individuals at genetic risk for bipolar disorder at various scales of investigation. PMID:22297067
Del Casale, Antonio; Ferracuti, Stefano; Rapinesi, Chiara; De Rossi, Pietro; Angeletti, Gloria; Sani, Gabriele; Kotzalidis, Georgios D; Girardi, Paolo
Several studies reported that hypnosis can modulate pain perception and tolerance by affecting cortical and subcortical activity in brain regions involved in these processes. We conducted an Activation Likelihood Estimation (ALE) meta-analysis on functional neuroimaging studies of pain perception under hypnosis to identify brain activation-deactivation patterns occurring during hypnotic suggestions aiming at pain reduction, including hypnotic analgesic, pleasant, or depersonalization suggestions (HASs). We searched the PubMed, Embase and PsycInfo databases; we included papers published in peer-reviewed journals dealing with functional neuroimaging and hypnosis-modulated pain perception. The ALE meta-analysis encompassed data from 75 healthy volunteers reported in 8 functional neuroimaging studies. HASs during experimentally-induced pain compared to control conditions correlated with significant activations of the right anterior cingulate cortex (Brodmann's Area [BA] 32), left superior frontal gyrus (BA 6), and right insula, and deactivation of right midline nuclei of the thalamus. HASs during experimental pain impact both cortical and subcortical brain activity. The anterior cingulate, left superior frontal, and right insular cortices activation increases could induce a thalamic deactivation (top-down inhibition), which may correlate with reductions in pain intensity. Copyright © 2016 Elsevier Ltd. All rights reserved.
Chan, Han; Tang, Yan-Ling; Lv, Xiao-Hang; Zhang, Gao-Fu; Wang, Mo; Yang, Hai-Ping; Li, Qiu
Background and objective Henoch-Schönlein purpura (HSP) is an important cause of chronic kidney disease in children. This meta-analysis identified risk factors associated with renal involvement in childhood HSP. Methods PubMed, Embase, and Web of Science were searched. The quality of all eligible studies was assessed using the Newcastle-Ottawa scale criteria. An analysis of possible risk factors was conducted to report the odds ratio (OR) and weighted mean difference (WMD). Results Thirteen studies (2398 children) revealed 20 possible and 13 significant risk factors associated with renal involvement in HSP, with the following meta-analysis estimates of OR and WMD, with 95% confidence intervals: older age (0.90, 0.61–1.19); age > 10 y (3.13, 1.39–7.07); male gender (1.36, 1.07–1.74); abdominal pain (1.94,1.24–3.04); gastrointestinal bleeding (1.86, 1.30–2.65); severe bowel angina (3.38, 1.17–9.80); persistent purpura (4.02, 1.22–13.25); relapse (4.70, 2.42–9.14); WBC > 15 × 109/L (2.42, 1.39–4.22); platelets > 500 × 109/L (2.98, 1.22–7.25); elevated antistreptolysin O (ASO) (2.17, 1.29–3.64); and decreased complement component 3 (C3) (3.13, 1.62–6.05). Factors not significantly associated with renal involvement were: blood pressure; orchitis; elevated C-reactive protein; elevated erythrocyte sedimentation rate (ESR); and elevated serum IgA/IgE or IgG. Arthritis/arthralgia may be a risk factor according to the criteria of the American College of Rheumatology (1.41, 1.01–1.96). Conclusion The following are associated with renal involvement in pediatric HSP: male gender; > 10 y old; severe gastrointestinal symptoms (abdominal pain, gastrointestinal bleeding, and severe bowel angina); arthritis/arthralgia; persistent purpura or relapse; WBC > 15 × 109/L; platelets > 500 × 109/L; elevated ASO; and low C3. Relevant clinical interventions for these risk factors may exert positive effects on the prevention of kidney disease during the early
Schwalbe, Craig S; Gearing, Robin E; MacKenzie, Michael J; Brewer, Kathryne B; Ibrahim, Rawan
Research to establish an evidence-base for the treatment of conduct problems and delinquency in adolescence is well established; however, an evidence-base for interventions with offenders who are diverted from the juvenile justice system has yet to be synthesized. The purpose of this study was to conduct a meta-analysis of experimental studies testing juvenile diversion programs and to examine the moderating effect of program type and implementation quality. A literature search using PsycINFO, Web of Science, and the National Criminal Justice Reference Service data-bases and research institute websites yielded 28 eligible studies involving 57 experimental comparisons and 19,301 youths. Recidivism was the most common outcome reported across all studies. Overall, the effect of diversion programs on recidivism was non-significant (k=45, OR=0.83, 95%CI=0.43-1.58). Of the five program types identified, including case management (k=18, OR=0.78), individual treatment (k=11, OR=0.83), family treatment (k=4, OR=0.57), youth court (k=6, OR=0.93), and restorative justice (k=6, OR=0.87), only family treatment led to a statistically significant reduction in recidivism. Restorative justice studies that were implemented with active involvement of researchers led to statistically significant reductions in recidivism (k=3, OR=0.69). Other outcomes, including frequency of offending, truancy, and psycho-social problems were reported infrequently and were not subjected to meta-analysis. High levels of heterogeneity characterize diversion research. Results of this study recommend against implementation of programs limited to case management and highlight the promise of family interventions and restorative justice. Copyright © 2011 Elsevier Ltd. All rights reserved.
Descatha, Alexis; Albo, Francesco; Leclerc, Annette; Carton, Matthieu; Godeau, Diane; Roquelaure, Yves; Petit, Audrey; Aublet-Cuvelier, Agnès
In view of recent published studies, a meta-analysis was undertaken on prospective studies in order to assess any association between lateral epicondylitis and physical exposure at work. Using the key words "lateral epicondylitis" AND "occupational" AND ("cohort" OR "longitudinal," OR "incidence") without limitations on the language or year of publication, original prospective studies were selected from 4 databases (PubMed, Scopus, Web of Science, and Base de Données de Santé Publique) after 2 rounds (valid design, valid association reported, and valid work exposure). Relevant associations between physical exposure at work and incident lateral epicondylitis were extracted from the articles, and a meta-risk was calculated using the generic variance approach (meta-odds ratios [meta-ORs]). From 2001 to 2014, 5 prospective studies were included. Among 6,922 included subjects (and 3,449 who were followed), 256 cases of incident lateral epicondylitis were diagnosed 2.5-6 years after baseline. All the published studies found a significant estimation of relative risk for a positive association between combined biomechanic exposure involving the wrist and/or elbow and incidence of lateral epicondylitis. The overall meta-OR was 2.6 (95% confidence interval 1.9-3.5), with a low heterogeneity (Q = 1.4, P > 0.05). Funnel plots and Egger's test did not suggest major publication bias. The results of this meta-analysis strongly support the hypothesis of an association between biomechanic exposure involving the wrist and/or elbow at work and incidence of lateral epicondylitis. © 2016, American College of Rheumatology.
Schwarzer, Guido; Rücker, Gerta
This book provides a comprehensive introduction to performing meta-analysis using the statistical software R. It is intended for quantitative researchers and students in the medical and social sciences who wish to learn how to perform meta-analysis with R. As such, the book introduces the key concepts and models used in meta-analysis. It also includes chapters on the following advanced topics: publication bias and small study effects; missing data; multivariate meta-analysis, network meta-analysis; and meta-analysis of diagnostic studies. .
Sooki, Zahra; Shariati, Mohammad; Chaman, Reza; Khosravi, Ahmad; Effatpanah, Mohammad; Keramat, Afsaneh
Context Family, especially the mother, has the most important role in the education, transformation of information, and health behaviors of girls in order for them to have a healthy transition from the critical stage of puberty, but there are different views in this regard. Objectives Considering the various findings about the source of information about puberty, a meta-analysis study was conducted to investigate the extent of the mother’s role in informing girls about puberty. Data Sources This meta-analysis study was based on English articles published from 2000 to February 2015 in the Scopus, PubMed, and Science direct databases and on Persian articles in the SID, Magiran, and Iran Medex databases with determined key words and their MeSH equivalent. Study Selection Quantitative cross-sectional articles were extracted by two independent researchers and finally 46 articles were selected based on inclusion criteria. STROBE list were used for evaluation of studies. Data Extraction The percent of mothers as the current and preferred source of gaining information about the process of puberty, menarche, and menstruation from the perspective of adolescent girls was extracted from the articles. The results of studies were analyzed using meta-analysis (random effects model) and the studies’ heterogeneity was analyzed using the I2 calculation index. Variance between studies was analyzed using tau squared (Tau2) and review manager 5 software. Results The results showed that, from the perspective of teenage girls in Iran and other countries, in 56% of cases, the mother was the current source of information about the process of puberty, menarche, and menstruation. The preferred source of information about the process of puberty, menarche, and menstruation was the mother in all studies at 60% (Iran 57%, and other countries 66%). Conclusions According to the findings of this study, it is essential that health professionals and officials of the ministry of health train
Full Text Available Association between polychlorinated biphenyl (PCB exposure and breast cancer risk has been widely studied, but the results remain controversial. We performed a meta-analysis to evaluate the evidences from observational studies on PCB exposure and breast cancer risk.Relevant studies with data on internal PCB dose were identified from PubMed, EMBASE, CBM and CNKI databases through November 2014. Multivariable-adjusted odds ratio (OR with 95% confidence intervals (CIs were applied to assess the association between PCB exposure and breast cancer risk. Heterogeneity test, sensitivity analysis, subgroup analysis and publication bias test were also performed. To further explore the association between specific groups of PCB congeners and breast cancer, we examined the PCB congeners classified, according to their structural, biological and pharmacokinetics properties, as group I (potentially estrogenic, group II (potentially anti-estrogenic and immunotoxic, dioxin-like, and group III (phenobarbital, CYP1A and CYP2B inducers, biologically persistent.Of 660 studies screened, 25 studies which met criteria were selected, involving a total of 12866 participants (6088 cases and 6778 controls from eight countries. The results showed that the risk of breast cancer was associated with group II (OR = 1.23, 95% CI: 1.08-1.40 and group III (OR = 1.25, 95% CI: 1.09-1.43 PCBs, but not with group I (OR = 1.10, 95%CI: 0.97-1.24 PCBs or total PCB exposure (OR = 1.09, 95%CI: 0.97-1.22.Our meta-analysis based on the selected studies found group II and group III PCB exposure might contribute to the risk of breast cancer. More studies in developing countries with higher PCB levels are needed, as well as studies to explore the relationships between mixtures of organochlorine compounds and breast cancer risk.
Hox, J.J.; Maas, C.J.M.; Lensvelt-Mulders, G.J.L.M.
The goal of meta-analysis is to integrate the research results of a number of studies on a specific topic. Characteristic for meta-analysis is that in general only the summary statistics of the studies are used and not the original data. When the published research results to be integrated
Madl, Amy K; Hollins, Dana M; Devlin, Kathryn D; Donovan, Ellen P; Dopart, Pamela J; Scott, Paul K; Perez, Angela L
Exposures to airborne asbestos during the removal and installation of internal gaskets and packing associated with a valve overhaul were characterized and compared to published data according to different variables (e.g., product, equipment, task, tool, setting, duration). Personal breathing zone and area samples were collected during twelve events simulating gasket and packing replacement, clean-up and clothing handling. These samples were analyzed using PCM and TEM methods and PCM-equivalent (PCME) airborne asbestos concentrations were calculated. A meta-analysis was performed to compare these data with airborne asbestos concentrations measured in other studies involving gaskets and packing. Short-term mechanic and assistant airborne asbestos concentrations during valve work averaged 0.013f/cc and 0.008f/cc (PCME), respectively. Area samples averaged 0.008f/cc, 0.005f/cc, and 0.003f/cc (PCME) for center, bystander, and remote background, respectively. Assuming a tradesman conservatively performs 1-3 gasket and/or packing replacements daily, an average 8-h TWA was estimated to be 0.002-0.010f/cc (PCME). Combining these results in a meta-analysis of the published exposure data showed that the majority of airborne asbestos exposures during work with gaskets and packing fall within a consistent and low range. Significant differences in airborne concentrations were observed between power versus manual tools and removal versus installation tasks. Airborne asbestos concentrations resulting from gasket and packing work during a valve overhaul are consistent with historical exposure data on replacement of asbestos-containing gasket and packing materials involving multiple variables and, in nearly all plausible scenarios, result in average airborne asbestos concentrations below contemporaneous occupational exposure limits for asbestos. Copyright © 2014 Elsevier Inc. All rights reserved.
Reddy, Varikasuvu Seshadri; Bukke, Suman; Dutt, Naveen; Rana, Puneet; Pandey, Arun Kumar
Available studies in the literature on the selenium levels in Alzheimer's disease (AD) are inconsistent with some studies reporting its decrease in the circulation, while others reported an increase or no change as compared to controls. The objective of this study was to perform a meta-analysis of circulatory (plasma/serum and blood), erythrocyte and cerebrospinal fluid (CSF) selenium levels in AD compared controls. We also performed a meta-analysis of the correlation coefficients (r) to demonstrate the associations between selenium and glutathione peroxidase (GPx) in AD patients. All major databases were searched for eligible studies. We included 12 case-control/observational studies reporting selenium concentrations in AD and controls. Pooled-overall effect size as standardized mean difference (SMD) and pooled r-values were generated using Review Manager 5.3 and MedCalc 15.8 software. Random-effects meta-analysis indicated a decrease in circulatory (SMD=-0.44), erythrocellular (SMD=-0.52) and CSF (SMD=-0.14) selenium levels in AD patients compared to controls. Stratified meta-analysis demonstrated that the selenium levels were decreased in both the subgroups with (SMD=-0.55) and without (SMD=-0.37) age matching between AD and controls. Our results also demonstrated a direct association between decreased selenium levels and GPx in AD. This meta-analysis suggests that circulatory selenium concentration is significantly lower in AD patients compared to controls and this decrease in selenium is directly correlated with an important antioxidant enzyme, the GPx, in AD. Copyright © 2017 Elsevier GmbH. All rights reserved.
Belyk, Michel; Kraft, Shelly Jo; Brown, Steven
Stuttering is a speech disorder characterised by repetitions, prolongations and blocks that disrupt the forward movement of speech. An earlier meta-analysis of brain imaging studies of stuttering (Brown et al., 2005) revealed a general trend towards rightward lateralization of brain activations and hyperactivity in the larynx motor cortex bilaterally. The present study sought not only to update that meta-analysis with recent work but to introduce an important distinction not present in the first study, namely the difference between 'trait' and 'state' stuttering. The analysis of trait stuttering compares people who stutter (PWS) with people who do not stutter when behaviour is controlled for, i.e., when speech is fluent in both groups. In contrast, the analysis of state stuttering examines PWS during episodes of stuttered speech compared with episodes of fluent speech. Seventeen studies were analysed using activation likelihood estimation. Trait stuttering was characterised by the well-known rightward shift in lateralization for language and speech areas. State stuttering revealed a more diverse pattern. Abnormal activation of larynx and lip motor cortex was common to the two analyses. State stuttering was associated with overactivation in the right hemisphere larynx and lip motor cortex. Trait stuttering was associated with overactivation of lip motor cortex in the right hemisphere but underactivation of larynx motor cortex in the left hemisphere. These results support a large literature highlighting laryngeal and lip involvement in the symptomatology of stuttering, and disambiguate two possible sources of activation in neuroimaging studies of persistent developmental stuttering. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
Full Text Available Epidemiologic studies exploring causal associations between serum lipids and breast cancer risk have reported contradictory results. We conducted a meta-analysis of prospective cohort studies to evaluate these associations.Relevant studies were identified by searching PubMed and EMBASE through April 2015. We included prospective cohort studies that reported relative risk (RR estimates with 95% confidence intervals (CIs for the associations of specific lipid components (i.e., total cholesterol [TC], high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol [LDL-C], and triglycerides [TG] with breast cancer risk. Either a fixed- or a random-effects model was used to calculate pooled RRs.Fifteen prospective cohort studies involving 1,189,635 participants and 23,369 breast cancer cases were included in the meta-analysis. The pooled RRs of breast cancer for the highest versus lowest categories were 0.96 (95% CI: 0.86-1.07 for TC, 0.92 (95% CI: 0.73-1.16 for HDL-C, 0.90 (95% CI: 0.77-1.06 for LDL-C, and 0.93 (95% CI: 0.86-1.00 for TG. Notably, for HDL-C, a significant reduction of breast cancer risk was observed among postmenopausal women (RR = 0.77, 95% CI: 0.64-0.93 but not among premenopausal women. Similar trends of the associations were observed in the dose-response analysis.Our findings suggest that serum levels of TG but not TC and LDL-C may be inversely associated with breast cancer risk. Serum HDL-C may also protect against breast carcinogenesis among postmenopausal women.
Vimaleswaran, Karani Santhanakrishnan; Luan, Jian'an; Andersen, Gitte
The protein encoded by the PPARGC1A gene is expressed at high levels in metabolically active tissues and is involved in the control of oxidative stress via reactive oxygen species detoxification. Several recent reports suggest that the PPARGC1A Gly482Ser (rs8192678) missense polymorphism may relate...... inversely with blood pressure. We used conventional meta-analysis methods to assess the association between Gly482Ser and systolic (SBP) or diastolic blood pressures (DBP) or hypertension in 13,949 individuals from 17 studies, of which 6,042 were previously unpublished observations. The studies comprised...
Jia, Peng-Li; Zhang, Chao; Yu, Jia-Jie; Xu, Chang; Tang, Li; Sun, Xin
Cooking has been regarded as a potential risk factor for lung cancer. We aim to investigate the evidence of cooking oil fume and risk of lung cancer. Medline and Embase were searched for eligible studies. We conducted a meta-analysis to summarize the evidences of case-control or cohort studies, with subgroup analysis for the potential discrepancy. Sensitivity analysis was employed to test the robustness. We included 23 observational studies, involving 9411 lung cancer cases. Our meta-analysis found that, for cooking female, the pooled OR of cooking oil fume exposure was 1.98 (95% CI 1.54, 2.54, I 2 = 79%, n = 15) among non-smoking population and 2.00 (95% CI 1.46, 2.74, I 2 = 75%, n = 10) among partly smoking population. For cooking males, the pooled OR of lung cancer was 1.15 (95% CI 0.71, 1.87; I 2 = 80%, n = 4). When sub grouped by ventilation condition, the pooled OR for poor ventilation was 1.20 (95% CI 1.10, 1.31, I 2 = 2%) compared to good ventilation. For different cooking methods, our results suggested that stir frying (OR = 1.89, 95% CI 1.23, 2.90; I 2 = 66%) was associated with increased risk of lung cancer while not for deep frying (OR = 1.41, 95% CI 0.87, 2.29; I 2 = 5%). Sensitivity analysis suggested our results were stable. Cooking oil fume is likely to be a risk factor for lung cancer for female, regardless of smoking status. Poor ventilation may increase the risk of lung cancer. Cooking methods may have different effect on lung cancer that deep frying may be healthier than stir frying.
Hinchliffe, Sally R.; Crowther, Michael J.; Phillips, Robert S.; Sutton, Alex J.
An individual diagnostic accuracy study rarely provides enough information to make conclusive recommendations about the accuracy of a diagnostic test; particularly when the study is small. Meta-analysis methods provide a way of combining information from multiple studies, reducing uncertainty in the result and hopefully providing substantial…
Hoogstra, Gerke J.; Van Dijk, Jouke; Florax, Raymond J. G. M.
Do jobs follow people or people follow jobs? A meta-analysis of Carlino–Mills studies. Spatial Economic Analysis. This study examines the classic question as to whether ‘jobs follow people’ or ‘people follow jobs’ by performing a meta-analysis of 321 results from 64 Carlino–Mills studies. It is
Moraes Silva, De K.M.; Bastiaansen, J.W.M.; Knol, E.F.; Merks, J.W.M.; Lopes, P.S.; Guimaraes, R.M.; Arendonk, van J.A.M.
Meta-analysis of results from multiple studies could lead to more precise quantitative trait loci (QTL) position estimates compared to the individual experiments. As the raw data from many different studies are not readily available, the use of results from published articles may be helpful. In this
Karadag, Engin; Bektas, Fatih; Çogaltay, Nazim; Yalçin, Mikail
In this meta-analysis study, different leadership styles were combined, and the relationship between educational leadership and student achievement was analyzed. In the literature review, 57 research articles/dissertations, independent from one another, were brought together, and 28,964 study subjects were included in the sample group. The results…
Hout, J. in't; Ioannidis, J.P.; Borm, G.F.; Goeman, J.J.
OBJECTIVES: Between-study heterogeneity plays an important role in random-effects models for meta-analysis. Most clinical trials are small, and small trials are often associated with larger effect sizes. We empirically evaluated whether there is also a relationship between trial size and
Zebrafish developmental toxicity testing is an emerging field, which faces considerable challenges regarding data meta-analysis and the establishment of standardized test protocols. Here, we present an initial correlation study on toxicity of 133 chemicals based on data in the li...
Lundahl, Brad W.; Kunz, Chelsea; Brownell, Cynthia; Tollefson, Derrik; Burke, Brian L.
Objective: The authors investigated the unique contribution motivational interviewing (MI) has on counseling outcomes and how MI compares with other interventions. Method: A total of 119 studies were subjected to a meta-analysis. Targeted outcomes included substance use (tobacco, alcohol, drugs, marijuana), health-related behaviors (diet,…
Ayaz, Mehmet Fatih; Sekerci, Hanifi
In this research, a meta-analysis study was conducted in order to determine the effects of constructivist learning approach on students' academic achievement. Master's thesis, doctoral dissertation and articles in national and international databases, which are realized between the years of 2003-2014, appropriate to the problem and which can be…
Berndt, Sonja I; Camp, Nicola J; Skibola, Christine F; Vijai, Joseph; Wang, Zhaoming; Gu, Jian; Nieters, Alexandra; Kelly, Rachel S; Smedby, Karin E; Monnereau, Alain; Cozen, Wendy; Cox, Angela; Wang, Sophia S; Lan, Qing; Teras, Lauren R; Machado, Moara; Yeager, Meredith; Brooks-Wilson, Angela R; Hartge, Patricia; Purdue, Mark P; Birmann, Brenda M; Vajdic, Claire M; Cocco, Pierluigi; Zhang, Yawei; Giles, Graham G; Zeleniuch-Jacquotte, Anne; Lawrence, Charles; Montalvan, Rebecca; Burdett, Laurie; Hutchinson, Amy; Ye, Yuanqing; Call, Timothy G; Shanafelt, Tait D; Novak, Anne J; Kay, Neil E; Liebow, Mark; Cunningham, Julie M; Allmer, Cristine; Hjalgrim, Henrik; Adami, Hans-Olov; Melbye, Mads; Glimelius, Bengt; Chang, Ellen T; Glenn, Martha; Curtin, Karen; Cannon-Albright, Lisa A; Diver, W Ryan; Link, Brian K; Weiner, George J; Conde, Lucia; Bracci, Paige M; Riby, Jacques; Arnett, Donna K; Zhi, Degui; Leach, Justin M; Holly, Elizabeth A; Jackson, Rebecca D; Tinker, Lesley F; Benavente, Yolanda; Sala, Núria; Casabonne, Delphine; Becker, Nikolaus; Boffetta, Paolo; Brennan, Paul; Foretova, Lenka; Maynadie, Marc; McKay, James; Staines, Anthony; Chaffee, Kari G; Achenbach, Sara J; Vachon, Celine M; Goldin, Lynn R; Strom, Sara S; Leis, Jose F; Weinberg, J Brice; Caporaso, Neil E; Norman, Aaron D; De Roos, Anneclaire J; Morton, Lindsay M; Severson, Richard K; Riboli, Elio; Vineis, Paolo; Kaaks, Rudolph; Masala, Giovanna; Weiderpass, Elisabete; Chirlaque, María-Dolores; Vermeulen, Roel C H|info:eu-repo/dai/nl/216532620; Travis, Ruth C; Southey, Melissa C; Milne, Roger L; Albanes, Demetrius; Virtamo, Jarmo; Weinstein, Stephanie; Clavel, Jacqueline; Zheng, Tongzhang; Holford, Theodore R; Villano, Danylo J; Maria, Ann; Spinelli, John J; Gascoyne, Randy D; Connors, Joseph M; Bertrand, Kimberly A; Giovannucci, Edward; Kraft, Peter; Kricker, Anne; Turner, Jenny; Ennas, Maria Grazia; Ferri, Giovanni M; Miligi, Lucia; Liang, Liming; Ma, Baoshan; Huang, Jinyan; Crouch, Simon; Park, Ju-Hyun; Chatterjee, Nilanjan; North, Kari E; Snowden, John A; Wright, Josh; Fraumeni, Joseph F; Offit, Kenneth; Wu, Xifeng; de Sanjose, Silvia; Cerhan, James R; Chanock, Stephen J; Rothman, Nathaniel; Slager, Susan L
Chronic lymphocytic leukemia (CLL) is a common lymphoid malignancy with strong heritability. To further understand the genetic susceptibility for CLL and identify common loci associated with risk, we conducted a meta-analysis of four genome-wide association studies (GWAS) composed of 3,100 cases and
Saunders, Catherine L.; Chiodini, Benedetta D.; Sham, Pak; Lewis, Cathryn M.; Abkevich, Victor; Adeyemo, Adebowale A.; de Andrade, Mariza; Arya, Rector; Berenson, Gerald S.; Blangero, John; Boehnke, Michael; Borecki, Ingrid B.; Chagnon, Yvon C.; Chen, Wei; Comuzzie, Anthony G.; Deng, Hong-Wen; Duggirala, Ravindranath; Feitosa, Mary F.; Froguel, Philippe; Hanson, Robert L.; Hebebrand, Johannes; Huezo-Dias, Patricia; Kissebah, Ahmed H.; Li, Weidong; Luke, Amy; Martin, Lisa J.; Nash, Matthew; Ohman, Muena; Palmer, Lyle J.; Peltonen, Leena; Perola, Markus; Price, R. Arlen; Redline, Susan; Srinivasan, Sathanur R.; Stern, Michael P.; Stone, Steven; Stringham, Heather; Turner, Stephen; Wijmenga, Cisca; Collier, David A.
Objective: The objective was to provide an overall assessment of genetic linkage data of BMI and BMI-defined obesity using a nonparametric genome scan meta-analysis. Research Methods and Procedures: We identified 37 published studies containing data on over 31,000 individuals from more than >10,000
Marjanovic-Umek, Ljubica; Fekonja-Peklaj, Urška
Child gender has been proved to affect toddlers'/children's language development in several studies, but its effect was not found to be stable across different ages or various aspects of language ability. The effect of gender on toddler's, children's and adolescents' language ability was examined in the present meta-analysis of ten Slovenian…
Jin, Jing; Rounds, James
A meta-analysis of longitudinal studies was conducted to investigate stability and change in work values across the life span. Both rank-order stability and mean-level change were investigated using an integrative classification for intrinsic, extrinsic, social and status work values (Ross, Schwartz, & Surkis, 1999). Results of rank-order…
In the study, a meta-analysis was conducted to determine the effect of the use of the learning cycle model on the achievements of the students. Doctorate and master theses, made between 2007 and 2016, were searched using the keywords in Turkish and English. As a result of the screening, a total of 123 dissertations, which used learning cycle…
Aune, D.; Lau, R.; Chan, D.S.M.; Vieira, R.; Greenwood, D.C.; Kampman, E.; Norat, T.
Background: Previous studies of the association between intake of dairy products and colorectal cancer risk have indicated an inverse association with milk, however, the evidence for cheese or other dairy products is inconsistent. Methods: We conducted a systematic review and meta-analysis to
de Wit, L.M.; van Straten, A.; Luppino, F; Penninx, B.W.J.H.; Zitman, F; Cuijpers, P.
To examine the nature of the association between depression and obesity and to determine possible underlying (demographic) factors, we conducted a meta-analysis of cross-sectional studies in the general population. We searched in major bibliographical databases (PubMed, Embase and PsycInfo) for
Dong, Debo; Wang, Yulin; Jia, Xiaoyan; Li, Yingjia; Chang, Xuebin; Vandekerckhove, Marie; Luo, Cheng; Yao, Dezhong
Impairment of face perception in schizophrenia is a core aspect of social cognitive dysfunction. This impairment is particularly marked in threatening face processing. Identifying reliable neural correlates of the impairment of threatening face processing is crucial for targeting more effective treatments. However, neuroimaging studies have not yet obtained robust conclusions. Through comprehensive literature search, twenty-one whole brain datasets were included in this meta-analysis. Using seed-based d-Mapping, in this voxel-based meta-analysis, we aimed to: 1) establish the most consistent brain dysfunctions related to threating face processing in schizophrenia; 2) address task-type heterogeneity in this impairment; 3) explore the effect of potential demographic or clinical moderator variables on this impairment. Main meta-analysis indicated that patients with chronic schizophrenia demonstrated attenuated activations in limbic emotional system along with compensatory over-activation in medial prefrontal cortex (MPFC) during threatening faces processing. Sub-task analyses revealed under-activations in right amygdala and left fusiform gyrus in both implicit and explicit tasks. The remaining clusters were found to be differently involved in different types of tasks. Moreover, meta-regression analyses showed brain abnormalities in schizophrenia were partly modulated by age, gender, medication and severity of symptoms. Our results highlighted breakdowns in limbic-MPFC circuit in schizophrenia, suggesting general inability to coordinate and contextualize salient threat stimuli. These findings provide potential targets for neurotherapeutic and pharmacological interventions for schizophrenia. Copyright © 2017 Elsevier B.V. All rights reserved.
Hattori, Satoshi; Zhou, Xiao-Hua
Publication bias is one of the most important issues in meta-analysis. For standard meta-analyses to examine intervention effects, the funnel plot and the trim-and-fill method are simple and widely used techniques for assessing and adjusting for the influence of publication bias, respectively. However, their use may be subjective and can then produce misleading insights. To make a more objective inference for publication bias, various sensitivity analysis methods have been proposed, including the Copas selection model. For meta-analysis of diagnostic studies evaluating a continuous biomarker, the summary receiver operating characteristic (sROC) curve is a very useful method in the presence of heterogeneous cutoff values. To our best knowledge, no methods are available for evaluation of influence of publication bias on estimation of the sROC curve. In this paper, we introduce a Copas-type selection model for meta-analysis of diagnostic studies and propose a sensitivity analysis method for publication bias. Our method enables us to assess the influence of publication bias on the estimation of the sROC curve and then judge whether the result of the meta-analysis is sufficiently confident or should be interpreted with much caution. We illustrate our proposed method with real data. Copyright © 2017 John Wiley & Sons, Ltd.
Yi Chun Lai
Full Text Available Background: Herpes zoster (HZ results from the reactivation of latent varicella zoster virus (VZV residing in dorsal root and cranial nerve ganglia. Advanced age and dysfunctional cell-mediated immune responses are well-established risk factors for VZV reactivation. There have been recent interests in whether there is an increased risk of the disease associated with a positive family history. Aims and Objectives: We aimed to conduct a meta-analysis to evaluate the association between HZ infection and family history. In addition, we investigated the dose-response relationship between HZ infection and the number of relatives with a history of HZ. Materials and Methods: Observational studies were searched from MEDLINE, EMBASE, and Cochrane Central Register from inception to April 15, 2015. The Meta-analysis of Observational Studies in Epidemiology guidelines were followed in conducting this study. To estimate the pooled odds ratio, random-effects model of DerSimonian and Laird was used. Heterogeneity between studies was assessed using the I2 statistic. A dose-response meta-analysis with studies that reported appropriate data were done using the generalized least squares for trend method. Results: Five studies, yielding a total of 4169 subjects, were identified for meta-analysis. Cases with HZ were 3.03 (95% confidence interval [CI]: 1.86–4.94, P < 0.001 and 3.27 (95% CI: 1.75–6.10, P < 0.001 times more likely to report the first-degree relatives and total relatives with a history of HZ, respectively. A significant positive dose-response relationship between the risk of HZ infection and the number of relatives with a history of HZ was also demonstrated (P < 0.001. Conclusions: This meta-analysis demonstrated that family history is a significant risk factor for HZ infection. This risk has a dose-response relationship with the number of relatives with a history of HZ.
Wiens, Stefan; Szychowska, Malina; Nilsson, Mats E
Because the auditory system is particularly useful in monitoring the environment, previous research has examined whether task-irrelevant, auditory distracters are processed even if subjects focus their attention on visual stimuli. This research suggests that attentionally demanding visual tasks decrease the auditory mismatch negativity (MMN) to simultaneously presented auditory distractors. Because a recent behavioral study found that high visual perceptual load decreased detection sensitivity of simultaneous tones, we used a similar task (n = 28) to determine if high visual perceptual load would reduce the auditory MMN. Results suggested that perceptual load did not decrease the MMN. At face value, these nonsignificant findings may suggest that effects of perceptual load on the MMN are smaller than those of other demanding visual tasks. If so, effect sizes should differ systematically between the present and previous studies. We conducted a selective meta-analysis of published studies in which the MMN was derived from the EEG, the visual task demands were continuous and varied between high and low within the same task, and the task-irrelevant tones were presented in a typical oddball paradigm simultaneously with the visual stimuli. Because the meta-analysis suggested that the present (null) findings did not differ systematically from previous findings, the available evidence was combined. Results of this meta-analysis confirmed that demanding visual tasks reduce the MMN to auditory distracters. However, because the meta-analysis was based on small studies and because of the risk for publication biases, future studies should be preregistered with large samples (n > 150) to provide confirmatory evidence for the results of the present meta-analysis. These future studies should also use control conditions that reduce confounding effects of neural adaptation, and use load manipulations that are defined independently from their effects on the MMN.
Wiens, Stefan; Szychowska, Malina; Nilsson, Mats E.
Because the auditory system is particularly useful in monitoring the environment, previous research has examined whether task-irrelevant, auditory distracters are processed even if subjects focus their attention on visual stimuli. This research suggests that attentionally demanding visual tasks decrease the auditory mismatch negativity (MMN) to simultaneously presented auditory distractors. Because a recent behavioral study found that high visual perceptual load decreased detection sensitivity of simultaneous tones, we used a similar task (n = 28) to determine if high visual perceptual load would reduce the auditory MMN. Results suggested that perceptual load did not decrease the MMN. At face value, these nonsignificant findings may suggest that effects of perceptual load on the MMN are smaller than those of other demanding visual tasks. If so, effect sizes should differ systematically between the present and previous studies. We conducted a selective meta-analysis of published studies in which the MMN was derived from the EEG, the visual task demands were continuous and varied between high and low within the same task, and the task-irrelevant tones were presented in a typical oddball paradigm simultaneously with the visual stimuli. Because the meta-analysis suggested that the present (null) findings did not differ systematically from previous findings, the available evidence was combined. Results of this meta-analysis confirmed that demanding visual tasks reduce the MMN to auditory distracters. However, because the meta-analysis was based on small studies and because of the risk for publication biases, future studies should be preregistered with large samples (n > 150) to provide confirmatory evidence for the results of the present meta-analysis. These future studies should also use control conditions that reduce confounding effects of neural adaptation, and use load manipulations that are defined independently from their effects on the MMN. PMID:26741815
Ma, Ning; Dinges, David F.; Basner, Mathias; Rao, Hengyi
Study Objectives: Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Design: Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. Methods: The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. Results: The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Conclusion: Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. Citation: Ma N, Dinges DF, Basner M, Rao H. How acute total
Reinwein, Joachim; Huberdeau, Lucie
A meta-analysis examined a series of studies by F.M. Dwyer on the effect of illustrations on text comprehension. Principal component analysis was used to reduce the four posttests used by Dwyer to more fundamental factors of learning, followed by analyses of variance. All nine studies (involving secondary-school and college students) in which…
Zong, Qiang; Ni, Dongkui; Li, Lijun; Shi, Yubo
This study aimed to explore the association between the rs2228570 polymorphism in the vitamin D receptor gene and degenerative disc disease (IDD), especially in European. We perform a meta-analysis to analyze the association after searching the relevant studies through China National Knowledge Infrastructure (CNKI), PubMed, Medline and EMBASE databases. And odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the strength of the association. A total of 10 studies involving 1,465 cases and 1,482 controls were included in the meta-analysis. Overall, there was not significant risk between rs2228570 polymorphism and degenerative disc disease in any genetic models. In addition, stratified analyses by ethnicity revealed similar results. However, stratified analyses by others indicates an association between IDD and the FF genotype (OR=0.62, 95% CI=0.43- 0.90, P=0.486) in age =40, and the F allele (OR=0.84, 95% CI=0.73-0.96, P=0.992), FF genotype (OR=0.78, 95% CI=0.65-0.93, P=0.853) in sample size > 300, and ff genotype (OR=0.91, 95% CI=1.11-3.29, P=0.783), FF genotype (OR=0.70, 95% CI=0.51-0.96, P=0.258) in Northern European. This meta-analysis suggested that the rs2228570 polymorphism may not be associated with degenerative disc disease. However, there existed some diversities, especially in age 300, countries in Northern Europe, suggesting that carrying the VDR FokI F allele may be a protective factor against IDD development. But a large number of well-designed studies are still required to assess this polymorphism and degenerative disc disease.
Vale Claire L
Full Text Available Abstract Background In April 2005, researchers based at the Medical Research Council Clinical Trials Unit, set out to involve women affected by cervical cancer in a systematic review and meta-analysis of individual patient data to evaluate treatments for this disease. Each of the women had previously been treated for cervical cancer. Following completion of the meta-analysis, we aimed to evaluate the process of involvement from the researcher and research partner perspective. Methods An advisory group was first established to give advice on recruiting, supporting and involving women and led to efforts to recruit women to take part in the systematic review using different approaches. Evaluation of the process and outcomes of the partnership between the systematic reviewers and the patients, in respect to what the partnership achieved; what worked well and what were the difficulties; what was learned and the resource requirements, took place during the conduct of the meta-analysis and again after completion of the project. Results Six women, each of whom had received treatments for cervical cancer, were recruited as Patient Research Partners and five of these women subsequently took part in a variety of activities around the systematic review. They attended progress meetings and all but one attended a meeting at which the first results of the review were presented to all collaborators and gave feedback. Three of the women also became involved in a further related research project which led to an editorial publication from the patient perspective and also participated, along with two lead researchers, in the evaluation of the process and outcomes. While they were generally positive about the experience, one Patient Research Partner questioned the extent of the impact patients could make to the systematic review process. Conclusions In general, researchers and patient research partners felt that they had learned a lot from the process and considered
Palermo, Sara; Benedetti, Fabrizio; Costa, Tommaso; Amanzio, Martina
The anticipation of pain has been investigated in a variety of brain imaging studies. Importantly, today there is no clear overall picture of the areas that are involved in different studies and the exact role of these regions in pain expectation remains especially unexploited. To address this issue, we used activation likelihood estimation meta-analysis to analyze pain anticipation in several neuroimaging studies. A total of 19 functional magnetic resonance imaging were included in the analysis to search for the cortical areas involved in pain anticipation in human experimental models. During anticipation, activated foci were found in the dorsolateral prefrontal, midcingulate and anterior insula cortices, medial and inferior frontal gyri, inferior parietal lobule, middle and superior temporal gyrus, thalamus, and caudate. Deactivated foci were found in the anterior cingulate, superior frontal gyrus, parahippocampal gyrus and in the claustrum. The results of the meta-analytic connectivity analysis provide an overall view of the brain responses triggered by the anticipation of a noxious stimulus. Such a highly distributed perceptual set of self-regulation may prime brain regions to process information where emotion, action and perception as well as their related subcategories play a central role. Not only do these findings provide important information on the neural events when anticipating pain, but also they may give a perspective into nocebo responses, whereby negative expectations may lead to pain worsening. © 2014 Wiley Periodicals, Inc.
Song Joon J
Full Text Available Abstract Background With the growing abundance of microarray data, statistical methods are increasingly needed to integrate results across studies. Two common approaches for meta-analysis of microarrays include either combining gene expression measures across studies or combining summaries such as p-values, probabilities or ranks. Here, we compare two Bayesian meta-analysis models that are analogous to these methods. Results Two Bayesian meta-analysis models for microarray data have recently been introduced. The first model combines standardized gene expression measures across studies into an overall mean, accounting for inter-study variability, while the second combines probabilities of differential expression without combining expression values. Both models produce the gene-specific posterior probability of differential expression, which is the basis for inference. Since the standardized expression integration model includes inter-study variability, it may improve accuracy of results versus the probability integration model. However, due to the small number of studies typical in microarray meta-analyses, the variability between studies is challenging to estimate. The probability integration model eliminates the need to model variability between studies, and thus its implementation is more straightforward. We found in simulations of two and five studies that combining probabilities outperformed combining standardized gene expression measures for three comparison values: the percent of true discovered genes in meta-analysis versus individual studies; the percent of true genes omitted in meta-analysis versus separate studies, and the number of true discovered genes for fixed levels of Bayesian false discovery. We identified similar results when pooling two independent studies of Bacillus subtilis. We assumed that each study was produced from the same microarray platform with only two conditions: a treatment and control, and that the data sets
Hong, Chuan; D Riley, Richard; Chen, Yong
Multivariate meta-analysis, which jointly analyzes multiple and possibly correlated outcomes in a single analysis, is becoming increasingly popular in recent years. An attractive feature of the multivariate meta-analysis is its ability to account for the dependence between multiple estimates from the same study. However, standard inference procedures for multivariate meta-analysis require the knowledge of within-study correlations, which are usually unavailable. This limits standard inference approaches in practice. Riley et al proposed a working model and an overall synthesis correlation parameter to account for the marginal correlation between outcomes, where the only data needed are those required for a separate univariate random-effects meta-analysis. As within-study correlations are not required, the Riley method is applicable to a wide variety of evidence synthesis situations. However, the standard variance estimator of the Riley method is not entirely correct under many important settings. As a consequence, the coverage of a function of pooled estimates may not reach the nominal level even when the number of studies in the multivariate meta-analysis is large. In this paper, we improve the Riley method by proposing a robust variance estimator, which is asymptotically correct even when the model is misspecified (ie, when the likelihood function is incorrect). Simulation studies of a bivariate meta-analysis, in a variety of settings, show a function of pooled estimates has improved performance when using the proposed robust variance estimator. In terms of individual pooled estimates themselves, the standard variance estimator and robust variance estimator give similar results to the original method, with appropriate coverage. The proposed robust variance estimator performs well when the number of studies is relatively large. Therefore, we recommend the use of the robust method for meta-analyses with a relatively large number of studies (eg, m≥50). When the
Hoff, Kevin A; Briley, Daniel A; Wee, Colin J M; Rounds, James
Vocational interests predict a variety of important outcomes and are among the most widely applied individual difference constructs in psychology and education. Despite over 90 years of research, little is known about the longitudinal development of interests. In this meta-analysis, the authors investigate normative changes in interests through adolescence and young adulthood. Effect sizes were aggregated from 49 longitudinal studies reporting mean-level changes in vocational interests, containing 98 total samples and 20,639 participants. Random effects meta-analytic regression models were used to assess age-related changes and gender differences across Holland's (1959, 1997) RIASEC categories and composite dimensions (people, things, data, and ideas). Results showed that mean-level interest scores generally increase with age, but effect sizes varied across interest categories and developmental periods. Adolescence was defined by two broad patterns of change: interest scores generally decreased during early adolescence, but then increased during late adolescence. During young adulthood, the most striking changes were found across the people and things orientations. Interests involving people tended to increase (artistic, social, and enterprising), whereas interests involving things either decreased (conventional) or remained constant (realistic and investigative). Gender differences associated with occupational stereotypes reached a lifetime peak during early adolescence, then tended to decrease in all subsequent age periods. Overall findings suggest there are normative changes in vocational interests from adolescence to adulthood, with important implications for developmental theories and the applied use of interests. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
HOU, LI-NA; LI, FEI; ZHOU, YOU; NIE, SHI-HUAI; SU, LIANG; CHEN, PING-AN; TAN, WAN-LONG; XU, DING-LI
The findings on the association between fish intake and the risk of heart failure (HF) have been inconsistent. The purpose of this study was to clarify this potential association. We searched for relevant studies in the PubMed database through January 2012 and manually reviewed references. Five independent prospective cohort studies involving 5,273 cases and 144,917 participants were included. The summary relative risk estimates (SRRE) based on the highest compared with the lowest category of fish consumption were estimated by variance-based meta-analysis. In addition, we performed sensitivity and dose-response analyses to examine the association. Overall, an absence of an association between fish intake and HF was observed (SRRE=1.00; 95% CI, 0.81–1.24). However, fried fish intake positively associated with HF (SRRE=1.40; 95% CI, 1.22–1.61). In addition, dose-response analysis of fried fish suggested that each increment of six fried fish per month corresponded to a 37% increase of HF rate (RR=1.37; 95% CI, 1.20–1.56). In conclusion, our findings suggest that there is no significant association between fish intake and risk of HF, with the exception of a possible positive correlation with individuals comsuming fried fish, based on a limited number of studies. Future studies are required to confirm these findings. PMID:23181122
Furnham, A; Hayward, R
Lay beliefs about the importance of 24 different contributors to overcoming 4 disorders that constitute primarily cognitive deficits were studied. A meta-analysis of previous programmatic studies in the area was performed so that 22 different psychological problems could be compared. In the present study, 107 participants completed a questionnaire indicating how effective 24 factors were in overcoming 4 specific problems: dyslexia, fear of flying, amnesia, and learning difficulties. Factor analysis revealed almost identical clusters (inner control, social consequences, understanding, receiving help, and fate) for each problem. The perceived relevance of those factors differed significantly between problems. Some individual difference factors (sex and religion) were found to predict certain factor attributions for specific disorders. A meta-analysis of the 5 studies in this series yielded a 6-factor structure comparable to those of the individual studies and provided results indicating the benefits and limitations of this kind of investigation. The clinical relevance of studying attributions for cure is considered.
Diener, Carsten; Kuehner, Christine; Brusniak, Wencke; Ubl, Bettina; Wessa, Michèle; Flor, Herta
Major depressive disorder (MDD) is characterized by altered emotional and cognitive functioning. We performed a voxel-based whole-brain meta-analysis of functional neuroimaging data on altered emotion and cognition in MDD. Forty peer-reviewed studies in English-language published between 1998 and 2010 were included, which used functional neuroimaging during cognitive-emotional challenge in adult individuals with MDD and healthy controls. All studies reported between-groups differences for whole-brain analyses in standardized neuroanatomical space and were subjected to Activation Likelihood Estimation (ALE) of brain cluster showing altered responsivity in MDD. ALE resulted in thresholded and false discovery rate corrected hypo- and hyperactive brain regions. Against the background of a complex neural activation pattern, studies converged in predominantly hypoactive cluster in the anterior insular and rostral anterior cingulate cortex linked to affectively biased information processing and poor cognitive control. Frontal areas showed not only similar under- but also over-activation during cognitive-emotional challenge. On the subcortical level, we identified activation alterations in the thalamus and striatum which were involved in biased valence processing of emotional stimuli in MDD. These results for active conditions extend findings from ALE meta-analyses of resting state and antidepressant treatment studies and emphasize the key role of the anterior insular and rostral anterior cingulate cortex for altered emotion and cognition in MDD. Copyright © 2012 Elsevier Inc. All rights reserved.
Full Text Available BACKGROUNDS/OBJECTIVE: The prevalence of diabetes is increasing rapidly all over the world. However, studies on passive smoking and type 2 diabetes have not been systematically assessed. Therefore, we conducted a meta-analysis to explore whether an association exists between passive smoking and risk of type 2 diabetes. METHODS: We searched PubMed, EMBASE, Cochrane library and Web of Science up to April 9(th, 2013, to identify prospective cohort studies that assessed passive smoking and risk of type 2 diabetes. The fixed-effect model was used to calculate the overall relative risk (RR. RESULT: 4 prospective cohort studies were included for analysis, with a total of 112,351 participants involved. The pooled RR was 1.28 (95% confidence interval (CI 1.14 to 1.44 comparing those who were exposed to passive smoking with those who were not. Subgroup, sensitivity analysis and publication bias test suggested the overall result of this analysis was robust. CONCLUSIONS: Passive smoking is associated with a significantly increased risk of type 2 diabetes. Further well-designed studies are warranted to confirm this association.
Zeng, Xian-Tao; Xia, Ling-Yun; Zhang, Yong-Gang; Li, Sheng; Leng, Wei-Dong; Kwong, Joey S W
Periodontal disease is linked to a number of systemic diseases such as cardiovascular diseases and diabetes mellitus. Recent evidence has suggested periodontal disease might be associated with lung cancer. However, their precise relationship is yet to be explored. Hence, this study aims to investigate the association of periodontal disease and risk of incident lung cancer using a meta-analytic approach. PubMed, Scopus, and ScienceDirect were searched up to June 10, 2015. Cohort and nested case-control studies investigating risk of lung cancer in patients with periodontal disease were included. Hazard ratios (HRs) were calculated, as were their 95% confidence intervals (CIs) using a fixed-effect inverse-variance model. Statistical heterogeneity was explored using the Q test as well as the I(2) statistic. Publication bias was assessed by visual inspection of funnel plots symmetry and Egger's test. Five cohort studies were included, involving 321,420 participants in this meta-analysis. Summary estimates based on adjusted data showed that periodontal disease was associated with a significant risk of lung cancer (HR = 1.24, 95% CI = 1.13 to 1.36; I(2) = 30%). No publication bias was detected. Subgroup analysis indicated that the association of periodontal disease and lung cancer remained significant in the female population. Evidence from cohort studies suggests that patients with periodontal disease are at increased risk of developing lung cancer.
Zatti, Cleonice; Rosa, Virgínia; Barros, Alcina; Valdivia, Lucianne; Calegaro, Vitor Crestani; Freitas, Lúcia Helena; Ceresér, Keila Maria Mendes; Rocha, Neusa Sica da; Bastos, Andre Goettems; Schuch, Felipe Barreto
Childhood trauma (CT) is a modifiable risk factor for lifetime suicide attempts (SA). However, the extent to which each type of CT increases SA risk is unclear. This study aimed to conduct a meta-analysis of longitudinal studies published in the last 10 years about the relationship between CT and lifetime SA risk. The PUBMED, PsycINFO, ISI, and EMBASE databases were searched for cohort studies that reported AS during follow-up and included an assessment of CT. A meta-analysis was conducted to identify potential effects of each type of CT on SA. Seven unique studies were included for review. Sexual (n=6, OR=3.73, 95%CI 2.94-4.75, pbroken home were not significantly associated with further SA. The modes of CT that most contribute to SA in later life are physical, emotional, and sexual abuse and physical neglect, in descending order. Copyright © 2017 Elsevier B.V. All rights reserved.
Guo, Ming; Qu, Hua; Xu, Lin; Shi, Da-Zhuo
Several epidemiological investigations have evaluated the correlation between tea consumption and risk of osteoporosis, but the results are inconsistent. Therefore, we conducted an updated meta-analysis of observational studies to assess this association. We searched for all relevant studies including cohort, cross-sectional, and case-control studies published from database inception to July 15, 2016, using MEDLINE EMBASE, and Cochrane Library. Polled odds ratios (ORs) were calculated using the random-effect model. Fourteen articles (16 studies) that examined 138523 patients were included in this meta-analysis. Seven studies concerning bone mineral density (BMD) showed an increase in BMD with tea consumption, including 4 cross-sectional studies (OR, 0.04, 95% confidence interval [CI], 0.01-0.08) and 3 cohort studies (OR, 0.01; 95% CI, 0.01-0.01). The remaining 9 studies concerning fracture, including 6 case-control studies and 3 cohort studies, showed no association between tea consumption and osteoporotic fracture (OR, 0.86; 95% CI, 0.74-1.01). This updated meta-analysis demonstrates that tea consumption could increase BMD, but the association with osteoporotic fracture requires further investigation. Together, the results highlight the need for future, high-quality-designed clinical trials on tea consumption and osteoporosis. Copyright © 2017 Elsevier Inc. All rights reserved.
Selmer, Randi; Haglund, Bengt; Furu, Kari
Purpose: Compare analyses of a pooled data set on the individual level with aggregate meta-analysis in a multi-database study. Methods: We reanalysed data on 2.3 million births in a Nordic register based cohort study. We compared estimated odds ratios (OR) for the effect of selective serotonin...... covariates in the pooled data set, and 1.53 (1.19–1.96) after country-optimized adjustment. Country-specific adjusted analyses at the substance level were not possible for RVOTO. Conclusion: Results of fixed effects meta-analysis and individual-based analyses of a pooled dataset were similar in this study...... reuptake inhibitors (SSRI) and venlafaxine use in pregnancy on any cardiovascular birth defect and the rare outcome right ventricular outflow tract obstructions (RVOTO). Common covariates included maternal age, calendar year, birth order, maternal diabetes, and co-medication. Additional covariates were...
Vitolo, Enrico; Tatu, Mona Karina; Pignolo, Claudia; Cauda, Franco; Costa, Tommaso; Ando', Agata; Zennaro, Alessandro
Voxel-based morphometry (VBM) and diffusion tensor imaging (DTI) are the most implemented methodologies to detect alterations of both gray and white matter (WM). However, the role of WM in mental disorders is still not well defined. We aimed at clarifying the role of WM disruption in schizophrenia and at identifying the most frequently involved brain networks. A systematic literature search was conducted to identify VBM and DTI studies focusing on WM alterations in patients with schizophrenia compared to control subjects. We selected studies reporting the coordinates of WM reductions and we performed the anatomical likelihood estimation (ALE). Moreover, we labeled the WM bundles with an anatomical atlas and compared VBM and DTI ALE-scores of each significant WM tract. A total of 59 studies were eligible for the meta-analysis. WM alterations were reported in 31 and 34 foci with VBM and DTI methods, respectively. The most occurred WM bundles in both VBM and DTI studies and largely involved in schizophrenia were long projection fibers, callosal and commissural fibers, part of motor descending fibers, and fronto-temporal-limbic pathways. The meta-analysis showed a widespread WM disruption in schizophrenia involving specific cerebral circuits instead of well-defined regions. Copyright © 2017 Elsevier B.V. All rights reserved.
Koo, Hoon Jung; Kwon, Jung-Hye
Purpose A meta-analysis of empirical studies performed in Korea was conducted to systematically investigate the associations between the indices of Internet addiction (IA) and psychosocial variables. Materials and Methods Systematic literature searches were carried out using the Korean Studies Information Service System, Research Information Sharing Service, Science Direct, Google Scholar, and references in review articles. The key words were Internet addiction, (Internet) game addiction, and...
Lee, Aeyoung; Myung, Seung Kwon; Cho, Jung Jin; Jung, Yu Jin; Yoon, Jong Lull; Kim, Mee Young
This study aimed to assess whether night shift work is associated with the risk of depression by using a meta-analysis of observational studies. We searched PubMed and EMBASE in August, 2016 to locate eligible studies and investigated the association between night shift work and the risk of depression, reporting outcome measures with adjusted odds ratios (ORs) or relative risks (RRs) and 95% confidence intervals (CIs). In the meta-analysis of a total of 11 observational studies with 9 cross-sectional study, 1 longitudinal study, and 1 cohort study, night shift work was significantly associated with an increased risk of depression (OR/RR, 1.43; 95% CI, 1.24-1.64; I² = 78.0%). Also, subgroup meta-analyses by gender, night shift work duration, type of occupation, continent, and type of publication showed that night shift work was consistently associated with the increased risk of depression. The current meta-analysis suggests that night shift work is associated with the increased risk of depression. However, further large prospective cohort studies are needed to confirm this association. © 2017 The Korean Academy of Medical Sciences.
Skibola Christine F
Full Text Available Abstract Background B-cell non-Hodgkin lymphoma represents a diverse group of hematological malignancies, of which follicular lymphoma (FL is one of the most common subtypes. Family and epidemiological studies suggest an important genetic role in the etiology of FL. In recent genome-wide association studies (GWAS of FL, several genetic susceptibility loci have been identified on chromosome 6p21.33 (rs6457327 and 6p21.32 (rs10484561, rs2647012 in the human leukocyte antigen class I and class II regions. To identify new genetic variants and further elucidate the genetic basis of FL, a meta-analysis was performed of the top 1000 SNPs associated with FL risk from two GWAS in the US, Denmark and Sweden (592 cases, 1541 controls, with independent validation in 107 cases and 681 controls. Results rs9275517 and rs3117222 in the HLA class II region were validated and inversely associated with FL risk (rs9275517: OR = 0.63, 95% CI = 0.55-0.73, p = 4.03 × 10-11; rs3117222: OR = 0.66, 95% CI = 0.57-0.77, p = 1.45 × 10-7. rs9275517, which is in high linkage disequilibrium with rs2647012 (r2 = 0.9, was no longer associated with FL after conditioning on rs2647012. The rs3117222 association was independent of established FL SNPs, but not of the HLA-DPB1*0301 allele. Using publicly available gene expression profiles with matching genotype information, we found that rs3117222 also was significantly correlated with increased HLA-DPB1 expression. Conclusions By performing a meta-analysis of two GWAS of FL, we further validated the relevance of HLA-DPB1*0301 as a protective allele in the pathogenesis of FL. Moreover, the protective rs3117222 A allele correlated with increased levels of HLA-DPB1, suggesting a possible disease mechanism involving HLA-DPB1 expression regulation. Our results add further support to the major role of HLA genetic variation in the pathogenesis of FL.
Veglia, Fabrizio; Loft, Steffen; Matullo, Giuseppe
in which bulky DNA adducts have been measured in blood samples collected from healthy subjects (N = 1947; average follow-up 51-137 months). In addition, we have performed a meta-analysis by identifying all articles on the same subject published up to the end of 2006, including case-control studies......). The association was evident only in current smokers and was absent in former smokers. Also the meta-analysis, which included both lung and bladder cancers, showed a statistically significant association in current smokers, whereas the results in never smokers were equivocal; in former smokers, no association......Bulky DNA adducts are biomarkers of exposure to aromatic compounds and of the ability of the individual to metabolically activate carcinogens and to repair DNA damage. Their ability to predict cancer onset is uncertain. We have performed a pooled analysis of three prospective studies on cancer risk...
Noels, Eline C; Lapid, Oren; Lindeman, Jan H N; Bastiaannet, Esther
The popularity of cosmetic breast augmentation and the incidence of breast cancer have been increasing worldwide. It has been hypothesized that the risk of breast cancer may be greater among patients who have undergone cosmetic breast implantation. The authors performed a meta-analysis of the available literature on the risk of breast cancer among women with cosmetic breast implants. The study was designed as a meta-analysis of observational studies. A systematic search of the English literature (published by August 28, 2013) was conducted in PubMed and EMBASE. Eligible reports were those that included relative risk (RR; the increased or decreased risk of breast cancer associated with breast implants) or the standardized incidence ratio (SIR) of the observed number of cases of breast cancer to the expected number of cases among patients that previously underwent cosmetic breast augmentation. Seventeen studies representing 7 cohorts were selected. Some of these were follow-up reports of previously published studies; in such cases, only the most recent reports were included in the meta-analysis. Summary SIR and RR rates and the corresponding 95% confidence intervals (CIs) were calculated with a random-effects (SIR) or fixed-effects (RR) model. The overall SIR estimate was 0.69 (95% CI, 0.56-0.85), and the overall RR, based on 4 studies, was 0.63 (95% CI, 0.56-0.71). Finding of this meta-analysis suggest that women who have undergone cosmetic breast implantation do not have an increased risk of breast cancer. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: firstname.lastname@example.org.
Palta, Priya; Samuel, Laura J; Miller, Edgar R; Szanton, Sarah L
To perform a systematic review and meta-analysis that quantitatively tests and summarizes the hypothesis that depression results in elevated oxidative stress and lower antioxidant levels. We performed a meta-analysis of studies that reported an association between depression and oxidative stress and/or antioxidant status markers. PubMed and EMBASE databases were searched for articles published from January 1980 through December 2012. A random-effects model, weighted by inverse variance, was performed to pool standard deviation (Cohen's d) effect size estimates across studies for oxidative stress and antioxidant status measures, separately. Twenty-three studies with 4980 participants were included in the meta-analysis. Depression was most commonly measured using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria. A Cohen's d effect size of 0.55 (95% confidence interval = 0.47-0.63) was found for the association between depression and oxidative stress, indicating a roughly 0.55 of 1-standard-deviation increase in oxidative stress among individuals with depression compared with those without depression. The results of the studies displayed significant heterogeneity (I(2) = 80.0%, p < .001). A statistically significant effect was also observed for the association between depression and antioxidant status markers (Cohen's d = -0.24, 95% confidence interval = -0.33 to -0.15). This meta-analysis observed an association between depression and oxidative stress and antioxidant status across many different studies. Differences in measures of depression and markers of oxidative stress and antioxidant status markers could account for the observed heterogeneity. These findings suggest that well-established associations between depression and poor heath outcomes may be mediated by high oxidative stress.
Wang, Xin; Yang, Hui-Hui; Liu, Yan; Zhou, Quan; Chen, Zi-Hua
A number of epidemiological studies have explored the association between lycopene or lycopene-rich food intake and the risk of colorectal cancer, but the results of these studies have not been consistent. We conducted a systematic review and meta-analysis of studies published in the PubMed and EMBASE databases to quantitatively assess the association between lycopene consumption and the risk of colorectal cancer. A total of 15 studies were included in the meta-analysis, and the summary relative risk (RR) for highest versus lowest category indicated no significant association between lycopene consumption and the risk of colorectal cancer [RR = 0.94, 95% confidence interval (CI): 0.80-1.10]. However, a significant inverse association was observed between lycopene consumption and the site of cancer in the colon (RR = 0.88, 95% CI: 0.81-0.96). We also found that the incidence of colon cancer and lycopene intake did not exhibit dose-response relationships. The Grades of Recommendations Assessment, Development and Evaluation (GRADE) quality in our study was very low. In conclusion, this meta-analysis indicates that lycopene consumption is not associated with the risk of colorectal cancer. Further research will be needed in this area to provide conclusive evidence.
Bécares, Laia; Dewey, Michael E; Das-Munshi, Jayati
Despite increased ethnic diversity in more economically developed countries it is unclear whether residential concentration of ethnic minority people (ethnic density) is detrimental or protective for mental health. This is the first systematic review and meta-analysis covering the international literature, assessing ethnic density associations with mental health outcomes. We systematically searched Medline, PsychINFO, Sociological Abstracts, Web of Science from inception to 31 March 2016. We obtained additional data from study authors. We conducted random-effects meta-analysis taking into account clustering of estimates within datasets. Meta-regression assessed heterogeneity in studies due to ethnicity, country, generation, and area-level deprivation. Our main exposure was ethnic density, defined as the residential concentration of own racial/ethnic minority group. Outcomes included depression, anxiety and the common mental disorders (CMD), suicide, suicidality, psychotic experiences, and psychosis. We included 41 studies in the review, with meta-analysis of 12 studies. In the meta-analyses, we found a large reduction in relative odds of psychotic experiences [odds ratio (OR) 0.82 (95% confidence interval (CI) 0.76-0.89)] and suicidal ideation [OR 0.88 (95% CI 0.79-0.98)] for each 10 percentage-point increase in own ethnic density. For CMD, depression, and anxiety, associations were indicative of protective effects of own ethnic density; however, results were not statistically significant. Findings from narrative review were consistent with those of the meta-analysis. The findings support consistent protective ethnic density associations across countries and racial/ethnic minority populations as well as mental health outcomes. This may suggest the importance of the social environment in patterning detrimental mental health outcomes in marginalized and excluded population groups.
Postmus, Iris; Warren, Helen R; Trompet, Stella
BACKGROUND: In addition to lowering low density lipoprotein cholesterol (LDL-C), statin therapy also raises high density lipoprotein cholesterol (HDL-C) levels. Inter-individual variation in HDL-C response to statins may be partially explained by genetic variation. METHODS AND RESULTS: We performed...... a meta-analysis of genome-wide association studies (GWAS) to identify variants with an effect on statin-induced high density lipoprotein cholesterol (HDL-C) changes. The 123 most promising signals with p
Dal, Jakob; Leisner, Michelle Z; Hermansen, Kasper
-2010) including 529 acromegaly cases was performed. Incident cancer diagnoses and mortality were compared to national rates estimating standardized incidence ratios (SIRs). A meta-analysis of cancer SIRs from 23 studies (including the present one) was performed. Results: The cohort study identified 81 cases...... in acromegaly (SIR 1.3 [95% CI: 1.1-1.6]), cancer-specific mortality was not. The meta-analysis yielded a SIR of overall cancer of 1.5 [95% CI: 1.2-1.8]. SIRs were elevated for colorectal cancer: 2.6 [95% CI: 1.7-4.0], thyroid cancer: 9.2 [95% CI: 4.2-19.9], breast cancer: 1.6 [1.1-2.3], gastric cancer: 2.0 [95......% CI: 1.4-2.9], and urinary tract cancer: 1.5 [95% CI: 1.0-2.3]). In general, cancer SIR was higher in single-center studies and in studies with meta-analysis...
Virues-Ortega, Javier; Julio, Flávia M; Pastor-Barriuso, Roberto
The intervention program for autism known as Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH) is considered an emerging practice for autism. In the present study we used state-of-the-art meta-analytical procedures to examine the pooled clinical effects of TEACCH in a variety of outcomes. A total of 13 studies were selected for meta-analysis totaling 172 individuals with autism exposed to TEACCH. Standardized measures of perceptual, motor, adaptive, verbal and cognitive skills were identified as treatment outcomes. We used inverse-variance weighted random effects meta-analysis supplemented with quality assessment, sensitivity analysis, meta-regression, and heterogeneity and publication bias tests. The results suggested that TEACCH effects on perceptual, motor, verbal and cognitive skills were of small magnitude in the meta-analyzed studies. Effects over adaptive behavioral repertoires including communication, activities of daily living, and motor functioning were within the negligible to small range. There were moderate to large gains in social behavior and maladaptive behavior. The effects of the TEACCH program were not moderated by aspects of the intervention such as duration (total weeks), intensity (hours per week), and setting (home-based vs. center-based). While the present meta-analysis provided limited support for the TEACCH program as a comprehensive intervention, our results should be considered exploratory owing to the limited pool of studies available. © 2013.
Full Text Available The relationship between psoriasis and metabolic syndrome is not well understood. Though multiple epidemiologic studies have suggested a link between psoriasis and metabolic syndrome, there is a lack of a comprehensive meta-analysis synthesizing the results of all available observational studies to date. In this meta-analysis, we examined global data on the relationship between psoriasis and odds of metabolic syndrome by searching for studies published between 1946-2016. Specifically, we analyzed the results from 35 observational studies from 20 countries with 1,450,188 total participants, of which 46,714 were psoriasis patients. The pooled odds ratio based on random effects analysis was 2.14 (95% CI 1.84-2.48. Publication bias was present, as evidenced by an Egger test and graphical visualization through a funnel plot (p = 0.001. Based on this comprehensive meta-analysis, psoriasis patients have higher odds of having metabolic syndrome when compared with the general population.
Lianhui, Yang; Meifei, Lian; Zhongyue, Hu; Yunzhi, Feng
Objective The aim of this study is to evaluate the relationship between periodontitis and hyperlipidemia risks through Meta-analysis. Methods Two researchers conducted an electronic search on PubMed, Cochrane Library, Embase, CBM, CNKI, Wanfang and VIP databases established until July 2016 for observational studies on the association between periodontitis and hyperlipidemia. The language used was limited to Chinese and English. After data extraction and quality evaluation of included trials, Meta-analysis was conducted using the RevMan 5.3 software. The GRADE 3.6 software was used to evaluate the quality level of the evidence. Results Six case-control studies and one cohort study were included. The results of Meta-analysis showed that serum triglyceride (TG) in patients with periodontitis was significantly higher than that of the periodontal health group (MD=50.50, 95% confidence interval=39.57-61.42, Pchronic periodontitis were 4.73 times (OR=4.73, 95% confidence interval=2.74-8.17, Pperiodontal healthy patients. No significant difference was observed between the group with high-density lipoprotein cholesterol (HDL-C) and that with low density lipoprotein cholesterol (LDL-C). Conclusion Current evidence indicates that a correlation exists between chronic periodontitis and hyperlipidemia, and chronic periodontitis is an independent risk factor for hyperlipidemia, especially for TC and TG in serum.
Zhang, Shaojing; Jia, Zhankui; Yan, Zechen; Yang, Jinjian
There have been inconsistent results about the association between consumption of fruits and vegetables and renal cell carcinoma (RCC) risk. We conducted a meta-analysis of the published observational studies to explore this association. Nineteen observational studies (4 cohort, 1 pooled and 14 case-control studies), involving 10,215 subjects with RCC were part of this meta-analysis. The SRR for the highest vs. the lowest intake of vegetables was 0.73 (95% CI: 0.63-0.85; Pheterogeneity = 0.004, I2 = 53.5%), whereas for fruits it was 0.86 (95% CI: 0.75-0.98; Pheterogeneity = 0.012, I2 = 47.4%). Linear dose-response analysis also showed similar results, e.g., for per 1 serving/day increment of vegetables, the SRR was 0.90 (95% CI: 0.84-0.96) and for fruits it was 0.97 (95% CI: 0.93-1.01). Nonlinear association was only observed for vegetables (Pnonlinearity = 0.001), but not for fruits (Pnonlinearity = 0.221). Eligible studies up to August 31, 2016 were identified and retrieved by searching MEDLINE and EMBASE databases along with manual review of the reference list from the retrieved studies. Quality of included studies was evaluated using Newcastle-Ottawa Quality Assessment Scale (NOS). Random-effects model was used to calculate summary relative risk (SRR) and corresponding 95% confidence interval (CI). This meta-analysis indicated a protective effect of consumption of vegetables and fruits on RCC risk. Further studies are warranted with prospective designs that use validated questionnaires and control for important confounders.
Yin, Xin-Hai; Huang, Guang-Lei; Lin, Du-Ren; Wan, Cheng-Cheng; Wang, Ya-Dong; Song, Ju-Kun; Xu, Ping
Many observational studies have shown that exposure to fluoride in drinking water is associated with hip fracture risk. However, the findings are varied or even contradictory. In this work, we performed a meta-analysis to assess the relationship between fluoride exposure and hip fracture risk. PubMed and EMBASE databases were searched to identify relevant observational studies from the time of inception until March 2014 without restrictions. Data from the included studies were extracted and analyzed by two authors. Summary relative risks (RRs) with corresponding 95% confidence intervals (CIs) were pooled using random- or fixed-effects models as appropriate. Sensitivity analyses and meta-regression were conducted to explore possible explanations for heterogeneity. Finally, publication bias was assessed. Fourteen observational studies involving thirteen cohort studies and one case-control study were included in the meta-analysis. Exposure to fluoride in drinking water does not significantly increase the incidence of hip fracture (RRs, 1.05; 95% CIs, 0.96-1.15). Sensitivity analyses based on adjustment for covariates, effect measure, country, sex, sample size, quality of Newcastle-Ottawa Scale scores, and follow-up period validated the strength of the results. Meta-regression showed that country, gender, quality of Newcastle-Ottawa Scale scores, adjustment for covariates and sample size were not sources of heterogeneity. Little evidence of publication bias was observed. The present meta-analysis suggests that chronic fluoride exposure from drinking water does not significantly increase the risk of hip fracture. Given the potential confounding factors and exposure misclassification, further large-scale, high-quality studies are needed to evaluate the association between exposure to fluoride in drinking water and hip fracture risk.
Full Text Available Many observational studies have shown that exposure to fluoride in drinking water is associated with hip fracture risk. However, the findings are varied or even contradictory. In this work, we performed a meta-analysis to assess the relationship between fluoride exposure and hip fracture risk.PubMed and EMBASE databases were searched to identify relevant observational studies from the time of inception until March 2014 without restrictions. Data from the included studies were extracted and analyzed by two authors. Summary relative risks (RRs with corresponding 95% confidence intervals (CIs were pooled using random- or fixed-effects models as appropriate. Sensitivity analyses and meta-regression were conducted to explore possible explanations for heterogeneity. Finally, publication bias was assessed.Fourteen observational studies involving thirteen cohort studies and one case-control study were included in the meta-analysis. Exposure to fluoride in drinking water does not significantly increase the incidence of hip fracture (RRs, 1.05; 95% CIs, 0.96-1.15. Sensitivity analyses based on adjustment for covariates, effect measure, country, sex, sample size, quality of Newcastle-Ottawa Scale scores, and follow-up period validated the strength of the results. Meta-regression showed that country, gender, quality of Newcastle-Ottawa Scale scores, adjustment for covariates and sample size were not sources of heterogeneity. Little evidence of publication bias was observed.The present meta-analysis suggests that chronic fluoride exposure from drinking water does not significantly increase the risk of hip fracture. Given the potential confounding factors and exposure misclassification, further large-scale, high-quality studies are needed to evaluate the association between exposure to fluoride in drinking water and hip fracture risk.
Zhong, Guochao; Wang, Yi; Tao, TieHong; Ying, Jun; Zhao, Yong
The association between daytime napping and mortality remains controversial. We conducted a meta-analysis to examine the associations between daytime napping and the risks of death from all causes, cardiovascular disease (CVD), and cancer. PubMed and Embase databases were searched through 19 September 2014. Prospective cohort studies that provided risk estimates of daytime napping and mortality were eligible for our meta-analysis. Two investigators independently performed study screening and data extraction. A random-effects model was used to estimate the combined effect size. Subgroup analyses were conducted to identify potential effect modifiers. Twelve studies, involving 130,068 subjects, 49,791 nappers, and 19,059 deaths, were included. Our meta-analysis showed that daytime napping was associated with an increased risk of death from all causes [n = 9 studies; hazard ratio (HR), 1.22; 95% confidence interval (CI), 1.14-1.31; I(2) = 42.5%]. No significant associations between daytime napping and the risks of death from CVD (n = 6 studies; HR, 1.20; 95% CI, 0.96-1.50; I(2) = 75.0%) and cancer (n = 4 studies; HR, 1.07; 95% CI, 0.99-1.15; I(2) = 8.9%) were found. There were no significant differences in risks of all-cause and CVD mortality between subgroups stratified by the prevalence of napping, follow-up duration, outcome assessment, age, and sex. Daytime napping is a predictor of increased all-cause mortality but not of CVD and cancer mortality. However, our findings should be treated with caution because of limited numbers of included studies and potential biases. Copyright © 2015. Published by Elsevier B.V.
Singh, Angad Pal; Zafer, Samreen; Pe'er, Itsik
Human genetics recently transitioned from GWAS to studies based on NGS data. For GWAS, small effects dictated large sample sizes, typically made possible through meta-analysis by exchanging summary statistics across consortia. NGS studies groupwise-test for association of multiple potentially-causal alleles along each gene. They are subject to similar power constraints and therefore likely to resort to meta-analysis as well. The problem arises when considering privacy of the genetic information during the data-exchange process. Many scoring schemes for NGS association rely on the frequency of each variant thus requiring the exchange of identity of the sequenced variant. As such variants are often rare, potentially revealing the identity of their carriers and jeopardizing privacy. We have thus developed MetaSeq, a protocol for meta-analysis of genome-wide sequencing data by multiple collaborating parties, scoring association for rare variants pooled per gene across all parties. We tackle the challenge of tallying frequency counts of rare, sequenced alleles, for metaanalysis of sequencing data without disclosing the allele identity and counts, thereby protecting sample identity. This apparent paradoxical exchange of information is achieved through cryptographic means. The key idea is that parties encrypt identity of genes and variants. When they transfer information about frequency counts in cases and controls, the exchanged data does not convey the identity of a mutation and therefore does not expose carrier identity. The exchange relies on a 3rd party, trusted to follow the protocol although not trusted to learn about the raw data. We show applicability of this method to publicly available exome-sequencing data from multiple studies, simulating phenotypic information for powerful meta-analysis. The MetaSeq software is publicly available as open source.
Ma, Ning; Dinges, David F; Basner, Mathias; Rao, Hengyi
Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. © 2015 Associated Professional Sleep Societies, LLC.
Kilbas, Imdat; Ciftci, Ihsan Hakki
In this study, a meta-analysis of Enterococcus isolates collected in 2000-2015 in Turkey and their susceptibility/resistance to antibiotics, clinical indications for initial drug treatment, and identification of alternative treatments was conducted. The meta-analysis examined antibiotic susceptibility/resistance in Enterococcus spp. isolates. The study was planned and conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Statements on antimicrobial resistance were grouped according to the antimicrobial stewardship programme (ASP). The mean resistance rates of Enterococcus faecalis to vancomycin (VAN) and linezolid (LNZ) were 1.0±2.2% and 1.9±2.6%, respectively, whereas the mean resistance rates of Enterococcus faecium to VAN and LNZ were 10.3±11.3% and 2.4±0%, respectively. This study is the first meta-analysis of the resistance of clinical Enterococcus isolates in Turkey to antimicrobial agents, which is a major problem stemming from the excessive usage of antibiotics. The development of antibiotic resistance in Turkey has changed over time. To support the practice of evidence-based medicine, more notifications about Enterococcus resistance status are needed, especially notifications following ASP rules. Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.
Garcez, Anderson; Leite, Heloísa Marquardt; Weiderpass, Elisabete; Paniz, Vera Maria Vieira; Watte, Guilherme; Canuto, Raquel; Olinto, Maria Teresa Anselmo
To perform a qualitative synthesis (systematic review) and quantitative analysis (meta-analysis) to summarize the evidence regarding the relationship between basal cortisol levels and metabolic syndrome (MetS) in adults. A systematic search was performed in the PubMed, Embase, and PsycINFO databases for observational studies on the association between basal cortisol levels and MetS. The quality of individual studies was assessed by the Newcastle-Ottawa score. A random effects model was used to report pooled quantitative results and the I 2 statistic was used to assess heterogeneity. Egger's and Begg's tests were used to evaluate publication bias. Twenty-six studies (19 cross-sectional and seven case-control) met the inclusion criteria for the systematic review. The majority was classified as having a low risk of bias and used established criteria for the diagnosis of MetS. Twenty-one studies provided data on basal cortisol levels as continuous values and were included in the meta-analysis; they comprised 35 analyses and 11,808 subjects. Pooled results showed no significant difference in basal cortisol levels between subjects with and without MetS (standardized mean difference [SMD] = 0.02, 95% confidence interval [CI]=-0.11 to 0.14). There was high heterogeneity between the studies when all comparisons were considered (I 2 = 83.1%;p meta-analysis of studies evaluating saliva samples showed no significantly lower basal cortisol levels among subjects with MetS (SMD=-0.18, 95% CI=-0.37 to 0.01), whereas those studies that evaluated serum samples (SMD = 0.11, 95% CI=-0.02 to 0.24) and urine samples (SMD = 0.73, 95% CI=-0.40 to 1.86) showed no significantly higher basal cortisol levels among subjects with MetS. In the subgroup and meta-regression analyses, a significant difference in basal cortisol levels was observed according to study design, population base, age, gender, cortisol level assessment method, and study quality. This systematic review
Planton, Samuel; Jucla, Mélanie; Roux, Franck-Emmanuel; Démonet, Jean-François
Handwriting is a modality of language production whose cerebral substrates remain poorly known although the existence of specific regions is postulated. The description of brain damaged patients with agraphia and, more recently, several neuroimaging studies suggest the involvement of different brain regions. However, results vary with the methodological choices made and may not always discriminate between "writing-specific" and motor or linguistic processes shared with other abilities. We used the "Activation Likelihood Estimate" (ALE) meta-analytical method to identify the cerebral network of areas commonly activated during handwriting in 18 neuroimaging studies published in the literature. Included contrasts were also classified according to the control tasks used, whether non-specific motor/output-control or linguistic/input-control. These data were included in two secondary meta-analyses in order to reveal the functional role of the different areas of this network. An extensive, mainly left-hemisphere network of 12 cortical and sub-cortical areas was obtained; three of which were considered as primarily writing-specific (left superior frontal sulcus/middle frontal gyrus area, left intraparietal sulcus/superior parietal area, right cerebellum) while others related rather to non-specific motor (primary motor and sensorimotor cortex, supplementary motor area, thalamus and putamen) or linguistic processes (ventral premotor cortex, posterior/inferior temporal cortex). This meta-analysis provides a description of the cerebral network of handwriting as revealed by various types of neuroimaging experiments and confirms the crucial involvement of the left frontal and superior parietal regions. These findings provide new insights into cognitive processes involved in handwriting and their cerebral substrates. Copyright © 2013 Elsevier Ltd. All rights reserved.
Virtanen, M.; Jokela, M.; Madsen, I. E.; Magnusson Hanson, L. L.; Lallukka, T.; Nyberg, S. T.; Alfredsson, L.; Batty, D.; Bjorner, J. B.; Borritz, M.; Burr, H.; Dragano, N.; Erbel, R.; Ferrie, J. E.; Heikkilä, K.
Objectives This systematic review and meta-analysis combined published study-level data and unpublished individual-participant data with the aim of quantifying the relation between long working hours and the onset of depressive symptoms. Methods We searched PubMed and Embase for published prospective cohort studies and included available cohorts with unpublished individual-participant data. We used a random-effects meta-analysis to calculate summary estimates across studies. Results We identi...
Lyssenko, Lisa; Schmahl, Christian; Bockhacker, Laura; Vonderlin, Ruben; Bohus, Martin; Kleindienst, Nikolaus
Dissociation is a complex, ubiquitous construct in psychopathology. Symptoms of dissociation are present in a variety of mental disorders and have been connected to higher burden of illness and poorer treatment response, and not only in disorders with high levels of dissociation. This meta-analysis offers a systematic and evidence-based study of the prevalence and distribution of dissociation, as assessed by the Dissociative Experiences Scale, within different categories of mental disorders, and it updates an earlier meta-analysis. More than 1,900 original publications were screened, and 216 were included in the meta-analysis, comprising 15,219 individuals in 19 diagnostic categories. The largest mean dissociation scores were found in dissociative disorders (mean scores >35), followed by posttraumatic stress disorder, borderline personality disorder, and conversion disorder (mean scores >25). Somatic symptom disorder, substance-related and addictive disorders, feeding and eating disorders, schizophrenia, anxiety disorder, OCD, and most affective disorders also showed mean dissociation scores >15. Bipolar disorders yielded the lowest dissociation scores (mean score, 14.8). The findings underline the importance of careful psychopathological assessment of dissociative symptoms in the entire range of mental disorders.
Evangelou, Evangelos; Kerkhof, Hanneke J; Styrkarsdottir, Unnur
Osteoarthritis (OA) is the most common form of arthritis with a clear genetic component. To identify novel loci associated with hip OA we performed a meta-analysis of genome-wide association studies (GWAS) on European subjects.......Osteoarthritis (OA) is the most common form of arthritis with a clear genetic component. To identify novel loci associated with hip OA we performed a meta-analysis of genome-wide association studies (GWAS) on European subjects....
Full Text Available Posttraumatic stress disorder (PTSD is a debilitating condition that develops in some people after exposure to a traumatic event. Brain-derived neurotrophic factor (BDNF is highly expressed in the mammalian brain and is thought to be involved in learning and memory processes. A nonsynonymous polymorphism in the BDNF gene, rs6265 (Val66Met, has been hypothesised to be associated with PTSD. Association studies examining the Val66Met polymorphism and PTSD have been inconclusive, likely due to the variability in type of trauma exposure analysed. Vietnam veterans (n=257 screened for PTSD and controlled for trauma exposure were genotyped for BDNF Val66Met. The association was not significant so we incorporated our data into a meta-analysis to obtain greater statistical power. A comprehensive search of more than 1237 articles revealed eight additional studies suitable for meta-analysis (n=3625. A random-effects meta-analysis observed a potential protective factor of the Val/Val genotype. After removing two studies with violation of Hardy-Weinberg equilibrium, findings for the Val/Val genotype reached significance. Subgroup analyses confirmed a trend for this finding. Limitations of some studies that inform this meta-analysis include poorly screened controls and a lack of examination of population stratification. Effectively designed studies should inform this line of research in the future.
Kira C. Taylor
locus in the supervillin gene, which encodes a platelet-associated factor and was previously associated with platelet thrombus formation in African Americans. If validated in other populations of African descent, these findings suggest potential new mechanisms involved in fracture that may be particularly important among African Americans. Keywords: Fracture, Osteoporosis, Genome-wide association study (GWAS, Meta-analysis, African American, Genetic association study
Full Text Available BACKGROUND: The association between NAD(PH:quinone oxidoreductase 1 (NQO1 gene C609T polymorphism (rs1800566 and lung cancer has been widely evaluated, and a definitive answer so far is lacking. We first conducted a case-control study to assess this association in northeastern Han Chinese, and then performed a meta-analysis to further address this issue. METHODOLOGY/PRINCIPAL FINDINGS: This case-control study involved 684 patients clinically diagnosed as lung cancer and 602 age-matched cancer-free controls from Harbin city, Heilongjiang province, China. Genotyping was conducted using the PCR-LDR (ligase detection reactions method. Meta-analysis was managed by STATA software. Data and study quality were assessed in duplicate. Our case-control association study indicated no significant difference in the genotype and allele distributions of C609T polymorphism between lung cancer patients and controls, consistent with the results of the further meta-analysis involving 7286 patients and 9167 controls under both allelic (odds ratio (OR = 0.99; 95% confidence interval (CI: 0.92-1.06; P = 0.692 and dominant (OR = 0.98; 95% CI: 0.89-1.08; P = 0.637 models. However, there was moderate evidence of between-study heterogeneity and low probability of publication bias. Further subgroup analyses by ethnicity, source of controls and sample size detected no positive associations in this meta-analysis. CONCLUSIONS: Our study in northeastern Han Chinese, along with the meta-analysis, failed to confirm the association of NQO1 gene C609T polymorphism with lung cancer risk, even across different ethnic populations.
Woutersen, Karlijn; Guadron, Leslie; van den Berg, Albert V; Boonstra, F Nienke; Theelen, Thomas; Goossens, Jeroen
The useful-field-of-view (UFOV) test measures the amount of information someone can extract from a visual scene in one glance. Its scores show relatively strong relationships with everyday activities. The UFOV test consists of three computer tests, suggested to measure processing speed and central vision, divided attention, and selective attention. However, other functions seem to be involved as well. In order to investigate the contribution of these suggested and other perceptual and cognitive functions, we performed a meta-analysis of 116 Pearson's correlation coefficients between UFOV scores and other test scores reported in 18 peer-reviewed articles. We divided these correlations into nine domains: attention, executive functioning, general cognition, memory, spatial ability, visual closure, contrast sensitivity, visual processing speed, and visual acuity. A multivariate mixed-effects model analysis revealed that each domain correlated significantly with each of the UFOV subtest scores. These correlations were stronger for Subtests 2 and 3 than for Subtest 1. Furthermore, some domains were more strongly correlated to the UFOV than others across subtests. We did not find interaction effects between subtest and domain, indicating that none of the UFOV subtests is more selectively sensitive to a particular domain than the others. Thus, none of the three UFOV subtests seem to measure one clear construct. Instead, a range of visual and cognitive functions is involved. Perhaps this is the reason for the UFOV's high ecological validity, as it involves many functions at once, making it harder to compensate if one of them fails.
Sprung, Manuel; Münch, Hannah M; Harris, Paul L; Ebesutani, Chad; Hofmann, Stefan G
In the course of development, children show increased insight and understanding of emotions-both of their own emotions and those of others. However, little is known about the efficacy of training programs aimed at improving children's understanding of emotion. To conduct an effect size analysis of trainings aimed at three aspects of emotion understanding: external aspects (i.e., the recognition of emotional expressions, understanding external causes of emotion, understanding the influence of reminders on present emotions); mental aspects (i.e., understanding desire-based emotions, understanding belief-based emotions, understanding hidden emotions); and reflective aspects (i.e., understanding the regulation of an emotion, understanding mixed emotions, understanding moral emotions). A literature search was conducted using PubMed, PsycInfo, the Cochrane Library, and manual searches. The search identified 19 studies or experiments including a total of 749 children with an average age of 86 months ( S.D .=30.71) from seven different countries. Emotion understanding training procedures are effective for improving external (Hedge's g = 0.62), mental (Hedge's g = 0.31), and reflective (Hedge's g = 0.64) aspects of emotion understanding. These effect sizes were robust and generally unrelated to the number and lengths of training sessions, length of the training period, year of publication, and sample type. However, training setting and social setting moderated the effect of emotion understanding training on the understanding of external aspects of emotion. For the length of training session and social setting, we observed significant moderator effects of training on reflective aspects of emotion. Emotion understanding training may be a promising tool for both preventive intervention and the psychotherapeutic process. However, more well-controlled studies are needed.
Full Text Available Background/Aims: The ET system might be involved in the pathogenesis of hypertensive disorders during pregnancy. The objective is to analyse the impact of ET-1 in hypertensive pregnant women by a strict meta-analysis of published human clinical studies. Methods: Based on the principle of Cochrane systematic reviews, Cohort studies in PubMed (Medline, Google Scholar and China Biological Medicine Database (CBM-disc designed to identify the role of endothelin-1 (ET-1 in the pathophysiology of gestational hypertension and preeclampsia were screened. Review Manager Version 5.0 (Rev-Man 5.0 was applied for statistical analysis. Mean difference and 95% confidence interval (CI were shown in inverse variance (IV fixed-effects model or IV random-effects model. Results: Sixteen published cohort studies including 1739 hypertensive cases and 409 controls were used in the meta-analysis. ET-1 plasma concentrations were higher in hypertensive pregnant women as compared to the controls (mean difference between groups: 19.02 [15.60～22.44], P < 0.00001,. These finding were driven by severity of hypertension and/or degree of proteinuria. Conclusion: Plasma ET-1 concentrations are elevated in hypertensive disorders during human pregnancy. In particular women with preeclampsia (hypertensive pregnant women with proteinuria have substantially elevated plasma ET-1 concentration as compared to pregnant women with normal blood pressure.
Hu, Dan; Huang, Junqian; Wang, Yuchun; Zhang, Dongfeng; Qu, Yan
We conducted a meta-analysis to summarize evidence from prospective cohort studies about the association of fruits and vegetables consumption with the risk of stroke. Pertinent studies were identified by a search of Embase and PubMed databases to January 2014. Study-specific relative risks with 95% confidence intervals were pooled using a random-effects model. Dose-response relationship was assessed by restricted cubic spline. Twenty prospective cohort studies were included, involving 16 981 stroke events among 760 629 participants. The multivariable relative risk (95% confidence intervals) of stroke for the highest versus lowest category of total fruits and vegetables consumption was 0.79 (0.75-0.84), and the effect was 0.77 (0.71-0.84) for fruits consumption and 0.86 (0.79-0.93) for vegetables consumption. Subgroup and meta-regression showed that the inverse association of total fruits and vegetables consumption with the risk of stroke was consistent in subgroup analysis. Citrus fruits, apples/pears, and leafy vegetables might contribute to the protection. The linear dose-response relationship showed that the risk of stroke decreased by 32% (0.68 [0.56-0.82]) and 11% (0.89 [0.81-0.98]) for every 200 g per day increment in fruits consumption (P for nonlinearity=0.77) and vegetables consumption (P for nonlinearity=0.62), respectively. Fruits and vegetables consumption are inversely associated with the risk of stroke. © 2014 American Heart Association, Inc.
Park, Yeong Mi; Youn, Jiyoung; Cho, Chang Ho; Kim, Sung Hi; Lee, Jung Eun
The relationship between folate and colorectal neoplasia remains controversial. We examined the association between serum folate concentrations and colorectal adenomas in a case-control study of Korean adults and conducted a meta-analysis. Our case-control study included 113 pairs of case and control who underwent colonoscopy and provided blood samples. We used multivariable conditional logistic regression models to obtain the odds ratios and 95% confidence interval (CIs). For meta-analysis, we identified the relevant studies by searching the PubMed database up to February 2017, included our case-control study and combined the study-specific relative risks (RRs) using a random-effects model. In this case-control study, we included 58 men and 55 women with colorectal adenomas and sex and fasting status matched the controls. We did not find any significant association between the serum folate levels and colorectal adenomas in either men or women. For meta-analysis, a total of eleven studies were included in our analysis and classified into two groups; polyp clearance group (PC) for the studies that included participants who underwent endoscopies and had their polyps removed at baseline; and no polyp clearance group (NPC) for the studies that included participants whose histories of endoscopies were unknown or who underwent their first endoscopies. Four PC (1,311 cases and 1,672 non-cases) and eight NPC studies (3,501 cases and 11,347 non-cases) were included. The combined RRs (95% CIs) comparing the bottom with the top categories of circulating folate levels were 1.07 (0.97-1.18) for the NPC group but 1.45 (1.16-1.74) for the PC group. Low circulating folate levels were associated with new adenoma formation.
Hobeika, Lucie; Diard-Detoeuf, Capucine; Garcin, Béatrice; Levy, Richard; Volle, Emmanuelle
Reasoning by analogy allows us to link distinct domains of knowledge and to transfer solutions from one domain to another. Analogical reasoning has been studied using various tasks that have generally required the consideration of the relationships between objects and their integration to infer an analogy schema. However, these tasks varied in terms of the level and the nature of the relationships to consider (e.g., semantic, visuospatial). The aim of this study was to identify the cerebral network involved in analogical reasoning and its specialization based on the domains of information and task specificity. We conducted a coordinate-based meta-analysis of 27 experiments that used analogical reasoning tasks. The left rostrolateral prefrontal cortex was one of the regions most consistently activated across the studies. A comparison between semantic and visuospatial analogy tasks showed both domain-oriented regions in the inferior and middle frontal gyri and a domain-general region, the left rostrolateral prefrontal cortex, which was specialized for analogy tasks. A comparison of visuospatial analogy to matrix problem tasks revealed that these two relational reasoning tasks engage, at least in part, distinct right and left cerebral networks, particularly separate areas within the left rostrolateral prefrontal cortex. These findings highlight several cognitive and cerebral differences between relational reasoning tasks that can allow us to make predictions about the respective roles of distinct brain regions or networks. These results also provide new, testable anatomical hypotheses about reasoning disorders that are induced by brain damage. Hum Brain Mapp 37:1953-1969, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Chen, Yong; Hong, Chuan; Ning, Yang; Su, Xiao
When conducting a meta-analysis of studies with bivariate binary outcomes, challenges arise when the within-study correlation and between-study heterogeneity should be taken into account. In this paper, we propose a marginal beta-binomial model for the meta-analysis of studies with binary outcomes. This model is based on the composite likelihood approach and has several attractive features compared with the existing models such as bivariate generalized linear mixed model (Chu and Cole, 2006) and Sarmanov beta-binomial model (Chen et al., 2012). The advantages of the proposed marginal model include modeling the probabilities in the original scale, not requiring any transformation of probabilities or any link function, having closed-form expression of likelihood function, and no constraints on the correlation parameter. More importantly, because the marginal beta-binomial model is only based on the marginal distributions, it does not suffer from potential misspecification of the joint distribution of bivariate study-specific probabilities. Such misspecification is difficult to detect and can lead to biased inference using currents methods. We compare the performance of the marginal beta-binomial model with the bivariate generalized linear mixed model and the Sarmanov beta-binomial model by simulation studies. Interestingly, the results show that the marginal beta-binomial model performs better than the Sarmanov beta-binomial model, whether or not the true model is Sarmanov beta-binomial, and the marginal beta-binomial model is more robust than the bivariate generalized linear mixed model under model misspecifications. Two meta-analyses of diagnostic accuracy studies and a meta-analysis of case-control studies are conducted for illustration. Copyright © 2015 John Wiley & Sons, Ltd.
Alharbi, Khalid Khalaf; Ali Khan, Imran; Alotaibi, Mohammad Abdullah; Saud Aloyaid, Abdullah; Al-Basheer, Haifa Abdulaziz; Alghamdi, Naelah Abdullah; Al-Baradie, Raid Saleem; Al-Sulaiman, A M
Stroke is a multifactorial and heterogeneous disorder, correlates with heritability and considered as one of the major diseases. The prior reports performed the variable models such as genome-wide association studies (GWAS), replication, case-control, cross-sectional and meta-analysis studies and still, we lack diagnostic marker in the global world. There are limited studies were carried out in Saudi population, and we aim to investigate the molecular association of single nucleotide polymorphisms (SNPs) identified through GWAS and meta-analysis studies in stroke patients in the Saudi population. In this case-control study, we have opted gender equality of 207 cases and 207 controls from the capital city of Saudi Arabia in King Saud University Hospital. The peripheral blood (5 ml) sample will be collected in two different vacutainers, and three mL of the coagulated blood will be used for lipid analysis (biochemical tests) and two mL will be used for DNA analysis (molecular tests). Genomic DNA will be extracted with the collected blood samples, and specific primers will be designed for the opted SNPs ( SORT1 -rs646218 and OLR1 -rs11053646 polymorphisms) and PCR-RFLP will be performed and randomly DNA sequencing will be carried out to cross check the results. The rs646218 and rs11053646 polymorphisms were significantly associated with allele, genotype and dominant models with and without crude odds ratios (OR's) and Multiple logistic regression analysis (p Saudi population. The current results were in the association with the prior study results documented through GWAS and meta-analysis association. However, other ethnic population studies should be performed to rule out in the human hereditary diseases.
Xu, Jiuhong; Song, Chunli; Song, Xiaochao; Zhang, Xi; Li, Xinli
To quantify the association between dietary and circulating carotenoids and fracture risk, a meta-analysis was conducted by searching MEDLINE and EMBASE databases for eligible articles published before May 2016. Five prospective and 2 case-control studies with 140,265 participants and 4,324 cases were identified in our meta-analysis. Among which 5 studies assessed the association between dietary carotenoids levels and hip fracture risk, 2 studies focused on the association between circulating carotenoids levels and any fracture risk. A random-effects model was employed to summarize the risk estimations and their 95% confidence intervals (CIs). Hip fracture risk among participants with high dietary total carotenoids intake was 28% lower than that in participants with low dietary total carotenoids (OR: 0.72; 95% CI: 0.51, 1.01). A similar risk of hip fracture was found for β-carotene based on 5 studies, the summarized OR for high vs. low dietary β-carotene was 0.72 (95% CI: 0.54, 0.95). However, a significant between-study heterogeneity was found (total carotene: I2 = 59.4%, P = 0.06; β-carotene: I2 = 74.4%, P = 0.04). Other individual carotenoids did not show significant associations with hip fracture risk. Circulating carotene levels had no significant association with any fracture risk, the pooled OR (95% CI) was 0.83 (0.59, 1.17). Based on the evidence from observational studies, our meta-analysis supported the hypothesis that higher dietary total carotenoids or β-carotene intake might be potentially associated with a low risk of hip fracture, however, future well-designed prospective cohort studies and randomized controlled trials are warranted to specify the associations between carotenoids and fracture.
Kevin P Keegan
Full Text Available Five independent groups have reported microarray studies that identify dozens of rhythmically expressed genes in the fruit fly Drosophila melanogaster. Limited overlap among the lists of discovered genes makes it difficult to determine which, if any, exhibit truly rhythmic patterns of expression. We reanalyzed data from all five reports and found two sources for the observed discrepancies, the use of different expression pattern detection algorithms and underlying variation among the datasets. To improve upon the methods originally employed, we developed a new analysis that involves compilation of all existing data, application of identical transformation and standardization procedures followed by ANOVA-based statistical prescreening, and three separate classes of post hoc analysis: cross-correlation to various cycling waveforms, autocorrelation, and a previously described fast Fourier transform-based technique. Permutation-based statistical tests were used to derive significance measures for all post hoc tests. We find application of our method, most significantly the ANOVA prescreening procedure, significantly reduces the false discovery rate relative to that observed among the results of the original five reports while maintaining desirable statistical power. We identify a set of 81 cycling transcripts previously found in one or more of the original reports as well as a novel set of 133 transcripts not found in any of the original studies. We introduce a novel analysis method that compensates for variability observed among the original five Drosophila circadian array reports. Based on the statistical fidelity of our meta-analysis results, and the results of our initial validation experiments (quantitative RT-PCR, we predict many of our newly found genes to be bona fide cyclers, and suggest that they may lead to new insights into the pathways through which clock mechanisms regulate behavioral rhythms.
Sing, C W; Cheng, V K F; Ho, D K C; Kung, A W C; Cheung, B M Y; Wong, I C K; Tan, K C B; Salas-Salvadó, J; Becerra-Tomas, N; Cheung, C L
The study aimed to prospectively evaluate if serum calcium is related to diabetes incidence in Hong Kong Chinese. The results showed that serum calcium has a significant association with increased risk of diabetes. The result of meta-analysis reinforced our findings. This study aimed to evaluate the association of serum calcium, including serum total calcium and albumin-corrected calcium, with incident diabetes in Hong Kong Chinese. We conducted a retrospective cohort study in 6096 participants aged 20 or above and free of diabetes at baseline. Serum calcium was measured at baseline. Incident diabetes was determined from several electronic databases. We also searched relevant databases for studies on serum calcium and incident diabetes and conducted a meta-analysis using fixed-effect modeling. During 59,130.9 person-years of follow-up, 631 participants developed diabetes. Serum total calcium and albumin-corrected calcium were associated with incident diabetes in the unadjusted model. After adjusting for demographic and clinical variables, the association remained significant only for serum total calcium (hazard ratio (HR), 1.32 (95 % confidence interval (CI), 1.02-1.70), highest vs. lowest quartile). In a meta-analysis of four studies including the current study, both serum total calcium (pooled risk ratio (RR), 1.38 (95 % CI, 1.15-1.65); I (2) = 5 %, comparing extreme quantiles) and albumin-corrected calcium (pooled RR, 1.29 (95 % CI, 1.03-1.61); I (2) = 0 %, comparing extreme quantiles) were associated with incident diabetes. Penalized regression splines showed that the association of incident diabetes with serum total calcium and albumin-correlated calcium was non-linear and linear, respectively. Elevated serum calcium concentration is associated with incident diabetes. The mechanism underlying this association warrants further investigation.
Shen, Ze-Tian; Wu, Xin-Hu; Li, Bing; Shen, Jun-shu; Wang, Zhen; Li, Jing; Zhu, Xi-Xu
Many studies have examined the association between the CYP2E1 Rsa Ι/Pst Ι (rs3813867) polymorphism gene polymorphisms and lung cancer risk in various populations, but their results have been inconsistent. The PubMed and CNKI database was searched for case-control studies published up to October 2013. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. In this meta-analysis, we assessed 23 published studies involving comprising 4727 lung cancer cases and 6220 controls of the association between CYP2E1 Rsa Ι/Pst Ι polymorphism and lung cancer risk. For the homozygote c2/c2 and c2 allele carriers (c1/c2 + c2/c2), the pooled ORs for all studies were 0.73(95% CI = 0.62-0.84; P = 0.005 for heterogeneity) and 0.84 (95% CI = 0.77-0.92; P = 0.001 for heterogeneity) when compared with the homozygous wild-type genotype (c1/c1). In the stratified analysis by ethnicity, the same significantly risks were found among Asians and mixed population for both the c2 allele carriers and homozygote c2/c2. However, no significant associations were found in Caucasian population all genetic models. This updated meta-analysis suggests that CYP2E1 Rsa Ι/Pst Ι c2 allele is a decreased risk factor for the developing lung cancer among Asians and mixed population. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.
Astuti, Yuliana; Wardhana, Ardyan; Watkins, Johnathan; Wulaningsih, Wahyu
Cigarette smoking is a risk factor for ageing-related disease, but its association with biological ageing, indicated by telomere length, is unclear. We systematically reviewed evidence evaluating association between smoking status and telomere length. Searches were performed in MEDLINE (Ovid) and EMBASE (Ovid) databases, combining variation of keywords "smoking" and "telomere". Data was extracted for study characteristics and estimates for association between smoking and telomere length. Quality of studies was assessed with a risk of bias score, and publication bias was assessed with a funnel plot. I 2 test was used to observe heterogeneity. Meta-analysis was carried out to compare mean difference in telomere length by smoking status, and a dose-response approach was carried out for pack-years of smoking and telomere length. A sensitivity analysis was carried out to examine sources of heterogeneity. A total of 84 studies were included in the review, and 30 among them were included in our meta-analysis. Potential bias was addressed in half of included studies, and there was little evidence of small study bias. Telomere length was shorter among ever smokers compared to never smokers (summary standard mean difference [SMD]: -0.11 (95% CI -0.16 to -0.07)). Similarly, shorter telomere length was found among smokers compared to non-smokers, and among current smokers compared to never or former smokers. Dose-response meta-analysis suggested an inverse trend between pack-years of smoking and telomere length. However, heterogeneity among some analyses was observed. Shorter telomeres among ever smokers compared to those who never smoked may imply mechanisms linking tobacco smoke exposure to ageing-related disease. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
Full Text Available Sedentary behavior is ubiquitous in modern adults' daily lives and it has been suggested to be associated with incident cancer. However, the results have been inconsistent. In this study, we performed a systematic review and meta-analysis of prospective cohort studies to clarify the association between sedentary behavior and incident cancer.PubMed and Embase databases were searched up to March 2014. All prospective cohort studies on the association between sedentary behavior and incident cancer were included. The summary relative risks (RRs with 95% confidence intervals (CIs were estimated using random effect model.A total of 17 prospective studies from 14 articles, including a total of 857,581 participants and 18,553 cases, were included in the analysis for sedentary behavior and risk of incident cancer. The overall meta-analysis suggested that sedentary behavior increased risk of cancer (RR = 1.20, 95%CI = 1.12-1.28, with no evidence of heterogeneity between studies (I(2 = 7.3%, P = 0.368. Subgroup analyses demonstrated that there were statistical associations between sedentary behavior and some cancer types (endometrial cancer: RR = 1.28, 95% CI = 1.08-1.53; colorectal cancer: RR = 1.30, 95%CI = 1.12-1.49; breast cancer: RR = 1.17, 95%CI = 1.03-1.33; lung cancer: RR = 1.27, 95%CI = 1.06-1.52. However, there was no association of sedentary behavior with ovarian cancer (RR = 1.26, 95%CI = 0.87-1.82, renal cell carcinoma (RR = 1.11, 95%CI = 0.87-1.41 or non-Hodgkin lymphoid neoplasms (RR = 1.09, 95%CI = 0.82-1.43.The present meta-analysis suggested that prolonged sedentary behavior was independently associated with an increased risk of incident endometrial, colorectal, breast, and lung cancers, but not with ovarian cancer, renal cell carcinoma or non-Hodgkin lymphoid neoplasms.
van den Berg, Stéphanie M; de Moor, Marleen H M; Verweij, K. J. H.
small sample sizes of those studies. Here, we report on a large meta-analysis of GWA studies for extraversion in 63,030 subjects in 29 cohorts. Extraversion item data from multiple personality inventories were harmonized across inventories and cohorts. No genome-wide significant associations were found...... at the single nucleotide polymorphism (SNP) level but there was one significant hit at the gene level for a long non-coding RNA site (LOC101928162). Genome-wide complex trait analysis in two large cohorts showed that the additive variance explained by common SNPs was not significantly different from zero...
Xu, Mei; Lu, Yong-Ping; Hasan, Ahmed Abdallah; Hocher, Berthold
A recent study revealed that global overexpression of ET-1 causes a slight reduction in systemic blood pressure. Moreover, heterozygous ET-1 knockout mice are hypertensive. The role of ET-1 in human hypertension was so far not addressed by a strict meta-analysis of published human clinical studies. We included studies published between January 1, 1990 and February 28, 2017. We included case control studies analyzing untreated essential hypertension or hypertensive patients where antihypertensive medication was discontinued for at least two weeks. Based on the principle of Cochrane systematic reviews, case control studies (CCSs) in PubMed (Medline) and Google Scholar designed to identify the role of endothelin-1 (ET-1) in the pathophysiological of hypertension were screened. Review Manager Version 5.0 (Rev-Man 5.0) was applied for statistical analysis. Mean difference and 95% confidence interval (CI) were shown in inverse variance (IV) fixed-effects model or IV random-effects models. Eleven studies fulfilling our in- and exclusion criteria were eligible for this meta-analysis. These studies included 450 hypertensive patients and 328 controls. Our meta-analysis revealed that ET-1 plasma concentrations were higher in hypertensive patients as compared to the control patients [mean difference between groups 1.57 pg/mL, 95%CI [0.47∼2.68, P = 0.005]. These finding were driven by patients having systolic blood pressure higher than 160 mmHg and diastolic blood pressure higher than 100 mmHg. This meta-analysis showed that hypertensive patients do have elevated plasma ET-1 concentrations. This finding is driven by those patients with high systolic/diastolic blood pressure. Given that the ET-1 gene did not appear in any of the whole genome association studies searching for hypertension associated gene loci, it is very likely that the elevated plasma ET-1 concentrations in hypertensive patients are secondary to hypertension and may reflect endothelial cell damage. © 2017 The
Kaasinen, Valtteri; Vahlberg, Tero
A meta-analysis of 142 positron emission tomography and single photon emission computed tomography studies that have investigated striatal presynaptic dopamine function in Parkinson disease (PD) was performed. Subregional estimates of striatal dopamine metabolism are presented. The aromatic L-amino-acid decarboxylase (AADC) defect appears to be consistently smaller than the dopamine transporter and vesicular monoamine transporter 2 defects, suggesting upregulation of AADC function in PD. The correlation between disease severity and dopamine loss appears linear, but the majority of longitudinal studies point to a negative exponential progression pattern of dopamine loss in PD. Ann Neurol 2017;82:873-882. © 2017 American Neurological Association.
Mirnejad, Reza; Jazi, Faramarz Masjedian; Mostafaei, Shayan; Sedighi, Mansour
Brucellosis is still one of the most challenging issues for health and the economy in many developing countries such as Iran. Considering the high prevalence of brucellosis, the aim of the current study was to systematically review published data about the annual incidence rate of this infection from different parts of Iran and provide an overall relative frequency (RF) for Iran using meta-analysis. We searched several databases including PubMed, ISI Web of Science, Scopus, google scholar, IranMedex and Iranian Scientific Information Database (SID) by using the following keywords: "Brucella", "Brucellosis", "Malta fever", "Mediterranean fever", "undulant fever", "zoonosis" and "Iran" in Title/Abstract/Keywords fields. Articles/Abstracts, which used clinical specimens and reported the incidence of brucellosis, were included in this review. Quality of studies was assessed by STROB and PRISMA forms. All statistical analyses were performed using STATA 11.0 (STATA Corp, College Station, TX) and P-values under 0.05 were considered statistically significant. Out of the 8326 results, we found 34 articles suitable, according to inclusion and exlusion criteria, for inclusion in this systematic review and meta-analysis. The pooled incidence of brucellosis was estimated 0.001% (95% confidence interval (CI) = 0.0005-0.0015%) annually. Relative frequency of brucellosis in different studies varied from 7.0/100000 to 276.41/100000 in Qom and Kermanshah provinces, respectively. This systematic-review and meta-analysis study showed that the highest incidences of brucellosis are occurred in west and northwest regions of Iran. Totally, the incidence of the disease in Iran is in the high range. Copyright © 2017 Elsevier Ltd. All rights reserved.
Full Text Available Abstract Background Meta-analysis is a statistical method for combining the results of primary studies. It is often used in systematic reviews and is increasingly a method and topic that appears in student dissertations. MetaLight is a freely available software application that runs simple meta-analyses and contains specific functionality to facilitate the teaching and learning of meta-analysis. While there are many courses and resources for meta-analysis available and numerous software applications to run meta-analyses, there are few pieces of software which are aimed specifically at helping those teaching and learning meta-analysis. Valuable teaching time can be spent learning the mechanics of a new software application, rather than on the principles and practices of meta-analysis. Findings We discuss ways in which the MetaLight tool can be used to present some of the main issues involved in undertaking and interpreting a meta-analysis. Conclusions While there are many software tools available for conducting meta-analysis, in the context of a teaching programme such software can require expenditure both in terms of money and in terms of the time it takes to learn how to use it. MetaLight was developed specifically as a tool to facilitate the teaching and learning of meta-analysis and we have presented here some of the ways it might be used in a training situation.
Zhan, Xin; Wang, Jie; Pan, Shufen; Lu, Caijuan
A large number of epidemiological studies have provided conflicting results about the relationship between tea consumption and ovarian cancer. This study aimed to clarify the association between tea consumption and ovarian cancer. A literature search of the MEDICINE, Scopus, PubMed, and Web of Science databases was performed in April 2016. A total of 18 (11 case-control and 7 cohort) studies, representing data for 701,857 female subjects including 8,683 ovarian cancer cases, were included in the meta-analysis. A random-effects meta-analysis was used to compute the pooled relative risks (RR), meta regression, and publication bias, and heterogeneity analyses were performed for the included trials. We found that tea consumption had a significant protective effect against ovarian cancer (relative risk [RR] = 0.86; 95% confidence interval [CI]: 0.76, 0.96). The relationship was confirmed particularly after adjusting for family history of cancer (RR = 0.85; 95% CI: 0.72, 0.97), menopause status (RR = 0.85; 95% CI: 0.72, 0.98), education (RR = 0.82; 95% CI: 0.68, 0.96), BMI (RR = 0.85; 95% CI: 0.70, 1.00) , smoking (RR = 0.83; 95% CI: 0.72, 0.93) and Jadad score of 3 (RR = 0.76; 95% CI: 0.56, 0.95) and 5 (RR = 0.74; 95% CI: 0.59, 0.89). The Begg's and Egger's tests (all P > 0.01) showed no evidence of publication bias. In conclusion, our meta-analysis showed an inverse association between tea consumption and ovarian cancer risk. High quality cohort-clinical trials should be conducted on different tea types and their relationship with ovarian cancer.
Tench, C R; Tanasescu, Radu; Constantinescu, C S; Auer, D P; Cottam, W J
Low power in neuroimaging studies can make them difficult to interpret, and Coordinate based meta-analysis (CBMA) may go some way to mitigating this issue. CBMA has been used in many analyses to detect where published functional MRI or voxel-based morphometry studies testing similar hypotheses report significant summary results (coordinates) consistently. Only the reported coordinates and possibly t statistics are analysed, and statistical significance of clusters is determined by coordinate density. Here a method of performing coordinate based random effect size meta-analysis and meta-regression is introduced. The algorithm (ClusterZ) analyses both coordinates and reported t statistic or Z score, standardised by the number of subjects. Statistical significance is determined not by coordinate density, but by a random effects meta-analyses of reported effects performed cluster-wise using standard statistical methods and taking account of censoring inherent in the published summary results. Type 1 error control is achieved using the false cluster discovery rate (FCDR), which is based on the false discovery rate. This controls both the family wise error rate under the null hypothesis that coordinates are randomly drawn from a standard stereotaxic space, and the proportion of significant clusters that are expected under the null. Such control is necessary to avoid propagating and even amplifying the very issues motivating the meta-analysis in the first place. ClusterZ is demonstrated on both numerically simulated data and on real data from reports of grey matter loss in multiple sclerosis (MS) and syndromes suggestive of MS, and of painful stimulus in healthy controls. The software implementation is available to download and use freely. Copyright © 2017 Elsevier Inc. All rights reserved.
Li, Shuxiang; Luo, Xiaomin; Wang, Peng; Sun, Han; Wang, Kun; Sun, Xiaoliang
The argument on the clinical effects between gap balancing (GB) and measured resection (MR) in total knee arthroplasty remains to be resolved. A systematic review and meta-analysis was performed to investigate which technique in total knee arthroplasty has better clinical effect. A total of 20 studies involving 2259 cases were included in the meta-analysis. The primary outcome measure was Knee Society Score (KSS), whereas the secondary outcomes included other function assessment systems (eg, range of motion, Western Ontario and McMaster University Osteoarthritis Index), radiological outcomes (eg, femoral component rotation, total outliers), revision rate, complications (eg, infection, loosening, instability), and surgical time. The GB technique was associated with statistically significant increases in the primary outcomes of KSS-function in 1 year. However, a mean difference of 2.12 points was below the minimal clinically important difference of 6 points. No differences were found in the analyses of KSS-knee and KSS-function in any other follow-up periods. Secondary outcome assessments showed significant decreased surgical time (mean difference, 16.18; P < .00001) for MR. Although statistically significant difference in favor of GB was identified in total outliers (risk ratio, 1.72, P = .0004), the 2 techniques were comparable in range of motion, Western Ontario and McMaster University Osteoarthritis Index, femoral component rotation, complications, and revision rate. We conclude that both techniques can result in equivalent results when done properly, and each surgeon must understand the strengths and weaknesses of each technique. Copyright © 2018 Elsevier Inc. All rights reserved.
Gong, Fei; Yao, Shuyuan; Wan, Jing; Gan, Xuedong
Epidemiological studies have shown inconsistent findings on the association between chocolate consumption and risk of heart failure (HF). We, therefore, performed a meta-analysis of prospective studies to determine the role of chocolate intake in the prevention of HF. We searched databases of PubMed, Web of Science, and Scopus through December 2016 and scrutinized the reference lists of relevant literatures to identify eligible studies. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) were aggregated using random effect models. The dose-response relationship between chocolate consumption and incident HF was also assessed. This meta-analysis is registered with PROSPERO, number CRD42017054230. Five prospective studies with 106,109 participants were finally included. Compared to no consumption of chocolate, the pooled HRs (95% CIs) of HF were 0.86 (0.82-0.91) for low-to-moderate consumption (chocolate consumption and risk of HF ( p for nonlinearity = 0.005). Compared with non-consumption, the HRs (95% CIs) of HF across chocolate consumption levels were 0.92 (0.88-0.97), 0.86 (0.78-0.94), 0.93 (0.85-1.03), and 1.07 (0.92-1.23) for 1, 3, 7, and 10 servings/week, respectively. In conclusion, chocolate consumption in moderation may be associated with a decreased risk of HF.
Dong, Jie; Zou, Jian; Yu, Xiao-Feng
To quantitatively assess the relationship between coffee consumption and incidence of pancreatic cancer in a meta-analysis of cohort studies. We searched MEDLINE, EMBASE, Science Citation Index Expanded and bibliographies of retrieved articles. Studies were included if they reported relative risks (RRs) and corresponding 95% CIs of pancreatic cancer with respect to frequency of coffee intake. We performed random-effects meta-analyses and meta-regressions of study-specific incremental estimates to determine the risk of pancreatic cancer associated with a 1 cup/d increment in coffee consumption. Fourteen studies met the inclusion criteria, which included 671,080 individuals (1496 cancer events) with an average follow-up of 14.9 years. Compared with individuals who did not drink or seldom drank coffee per day, the pooled RR of pancreatic cancer was 0.82 (95% CI: 0.69-0.95) for regular coffee drinkers, 0.86 (0.76-0.96) for low to moderate coffee drinkers, and 0.68 (0.51-0.84) for high drinkers. In subgroup analyses, we noted that, coffee drinking was associated with a reduced risk of pancreatic cancer in men, while this association was not seen in women. These associations were also similar in studies from North America, Europe, and the Asia-Pacific region. Findings from this meta-analysis suggest that there is an inverse relationship between coffee drinking and risk of pancreatic cancer.
Cui, Lingling; Liu, Xinxin; Tian, Yalan; Xie, Chen; Li, Qianwen; Cui, Han; Sun, Changqing
Flavonoids have been suggested to play a chemopreventive role in carcinogenesis. However, the epidemiologic studies assessing dietary intake of flavonoids and esophageal cancer risk have yielded inconsistent results. This study was designed to examine the association between flavonoids, each flavonoid subclass, and the risk of esophageal cancer with a meta-analysis approach. We searched for all relevant studies with a prospective cohort or case-control study design published from January 1990 to April 2016, using PUBMED, EMBASE, and Web of Science. Pooled odds ratios (ORs) were calculated using fixed or random-effect models. In total, seven articles including 2629 cases and 481,193 non-cases were selected for the meta-analysis. Comparing the highest-intake patients with the lowest-intake patients for total flavonoids and for each flavonoid subclass, we found that anthocyanidins (OR = 0.60, 95% CI: 0.49-0.74), flavanones (OR = 0.65, 95% CI: 0.49-0.86), and flavones (OR = 0.78, 95% CI 0.64-0.95) were inversely associated with the risk of esophageal cancer. However, total flavonoids showed marginal association with esophageal cancer risk (OR = 0.78, 95% CI: 0.59-1.04). In conclusion, our study suggested that dietary intake of total flavonoids, anthocyanidins, flavanones, and flavones might reduce the risk of esophageal cancer.
Larsson, Susanna C; Drca, Nikola; Jensen-Urstad, Mats; Wolk, Alicja
Chocolate consumption has been inconsistently associated with risk of atrial fibrillation (AF). We investigated the association between chocolate consumption and risk of AF in Swedish adults from two cohort studies and conducted a meta-analysis to summarize available evidence from cohort studies on this topic. Our study population comprised 40,009 men from the Cohort of Swedish Men and 32,486 women from the Swedish Mammography Cohort. Incident AF cases were ascertained through linkage with the Swedish National Patient Register. Published cohort studies of chocolate consumption in relation to risk of AF were identified by a PubMed search through September 14, 2017. During a mean follow-up of 14.6 years, AF was diagnosed in 9978 Swedish men and women. Compared with non-consumers, the multivariable hazard ratio of AF for those in the highest category of chocolate consumption (≥3-4 servings/week) was 0.96 (95% CI 0.88-1.04). In a random-effects meta-analysis of 5 cohort studies, including 180,454 participants and 16,356 AF cases, the hazard ratios of AF were 0.97 (95% CI 0.94-1.01) per 2 servings/week increase in chocolate consumption and 0.96 (95% CI 0.90-1.03) for the highest versus lowest category of chocolate consumption. Available data provide no evidence of an association of chocolate consumption with risk of AF. Copyright © 2017 Elsevier Inc. All rights reserved.
Gong, Fei; Yao, Shuyuan; Wan, Jing; Gan, Xuedong
Epidemiological studies have shown inconsistent findings on the association between chocolate consumption and risk of heart failure (HF). We, therefore, performed a meta-analysis of prospective studies to determine the role of chocolate intake in the prevention of HF. We searched databases of PubMed, Web of Science, and Scopus through December 2016 and scrutinized the reference lists of relevant literatures to identify eligible studies. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) were aggregated using random effect models. The dose–response relationship between chocolate consumption and incident HF was also assessed. This meta-analysis is registered with PROSPERO, number CRD42017054230. Five prospective studies with 106,109 participants were finally included. Compared to no consumption of chocolate, the pooled HRs (95% CIs) of HF were 0.86 (0.82–0.91) for low-to-moderate consumption (chocolate consumption and risk of HF (p for nonlinearity = 0.005). Compared with non-consumption, the HRs (95% CIs) of HF across chocolate consumption levels were 0.92 (0.88–0.97), 0.86 (0.78–0.94), 0.93 (0.85–1.03), and 1.07 (0.92–1.23) for 1, 3, 7, and 10 servings/week, respectively. In conclusion, chocolate consumption in moderation may be associated with a decreased risk of HF. PMID:28425931
Kim, Kyung Won; Choi, Sang Hyun; Huh, Jimi; Park, Seong Ho; Lee, June Young
Meta-analysis of diagnostic test accuracy studies differs from the usual meta-analysis of therapeutic/interventional studies in that, it is required to simultaneously analyze a pair of two outcome measures such as sensitivity and specificity, instead of a single outcome. Since sensitivity and specificity are generally inversely correlated and could be affected by a threshold effect, more sophisticated statistical methods are required for the meta-analysis of diagnostic test accuracy. Hierarchical models including the bivariate model and the hierarchical summary receiver operating characteristic model are increasingly being accepted as standard methods for meta-analysis of diagnostic test accuracy studies. We provide a conceptual review of statistical methods currently used and recommended for meta-analysis of diagnostic test accuracy studies. This article could serve as a methodological reference for those who perform systematic review and meta-analysis of diagnostic test accuracy studies
Aung, Theingi; Halsey, Jim; Kromhout, Daan; Gerstein, Hertzel C; Marchioli, Roberto; Tavazzi, Luigi; Geleijnse, Johanna M; Rauch, Bernhard; Ness, Andrew; Galan, Pilar; Chew, Emily Y; Bosch, Jackie; Collins, Rory; Lewington, Sarah; Armitage, Jane; Clarke, Robert
Current guidelines advocate the use of marine-derived omega-3 fatty acids supplements for the prevention of coronary heart disease and major vascular events in people with prior coronary heart disease, but large trials of omega-3 fatty acids have produced conflicting results. To conduct a meta-analysis of all large trials assessing the associations of omega-3 fatty acid supplements with the risk of fatal and nonfatal coronary heart disease and major vascular events in the full study population and prespecified subgroups. This meta-analysis included randomized trials that involved at least 500 participants and a treatment duration of at least 1 year and that assessed associations of omega-3 fatty acids with the risk of vascular events. Aggregated study-level data were obtained from 10 large randomized clinical trials. Rate ratios for each trial were synthesized using observed minus expected statistics and variances. Summary rate ratios were estimated by a fixed-effects meta-analysis using 95% confidence intervals for major diseases and 99% confidence intervals for all subgroups. The main outcomes included fatal coronary heart disease, nonfatal myocardial infarction, stroke, major vascular events, and all-cause mortality, as well as major vascular events in study population subgroups. Of the 77 917 high-risk individuals participating in the 10 trials, 47 803 (61.4%) were men, and the mean age at entry was 64.0 years; the trials lasted a mean of 4.4 years. The associations of treatment with outcomes were assessed on 6273 coronary heart disease events (2695 coronary heart disease deaths and 2276 nonfatal myocardial infarctions) and 12 001 major vascular events. Randomization to omega-3 fatty acid supplementation (eicosapentaenoic acid dose range, 226-1800 mg/d) had no significant associations with coronary heart disease death (rate ratio [RR], 0.93; 99% CI, 0.83-1.03; P = .05), nonfatal myocardial infarction (RR, 0.97; 99% CI, 0.87-1.08; P = .43) or any
Maund, Emma; Guski, Louise Schow; Gøtzsche, Peter C.
BACKGROUND: The European Medicines Agency makes clinical study reports publicly available and publishes reasons for not approving applications for marketing authorization. Duloxetine has been approved in Europe for the treatment of stress urinary incontinence in women. The reported adverse effects...... of duloxetine include mental health problems and suicidality. We obtained clinical study reports from the European Medicines Agency concerning use of this drug for stress urinary incontinence. METHODS: We performed a meta-analysis of 4 randomized placebo-controlled trials of duloxetine (involving a total...... of 1913 patients) submitted to the European Medicines Agency for marketing approval for the indication of stress urinary incontinence in women. We used data from the clinical study reports (totalling 6870 pages and including individual patient data) to assess benefits (including frequency of incontinence...
Aune, D; Chan, D S M; Vieira, A R; Rosenblatt, D A Navarro; Vieira, R; Greenwood, D C; Norat, T
Evidence for an association between fruit and vegetable intake and breast cancer risk is inconclusive. To clarify the association, we conducted a systematic review and meta-analysis of the evidence from prospective studies. We searched PubMed for prospective studies of fruit and vegetable intake and breast cancer risk until April 30, 2011. We included fifteen prospective studies that reported relative risk estimates and 95 % confidence intervals (CIs) of breast cancer associated with fruit and vegetable intake. Random effects models were used to estimate summary relative risks. The summary relative risk (RR) for the highest versus the lowest intake was 0.89 (95 % CI: 0.80-0.99, I (2) = 0 %) for fruits and vegetables combined, 0.92 (95 % CI: 0.86-0.98, I (2) = 9 %) for fruits, and 0.99 (95 % CI: 0.92-1.06, I (2) = 20 %) for vegetables. In dose-response analyses, the summary RR per 200 g/day was 0.96 (95 % CI: 0.93-1.00, I (2) = 2 %) for fruits and vegetables combined, 0.94 (95 % CI: 0.89-1.00, I (2) = 39 %) for fruits, and 1.00 (95 % CI: 0.95-1.06, I (2) = 17 %) for vegetables. In this meta-analysis of prospective studies, high intake of fruits, and fruits and vegetables combined, but not vegetables, is associated with a weak reduction in risk of breast cancer.
Hu, Ji-Yi; Hu, Yi-Wang; Zhou, Jiao-Jiao; Zhang, Meng-Wen; Li, Dan; Zheng, Shu
To conduct an updated meta-analysis of prospective studies addressing the association between garlic consumption and colorectal cancer. Eligible cohort studies were identified by searching MEDLINE (PubMed) and screening the references of related articles published up to October 2013. Meta-analyses were conducted for colorectal cancer in relation to consumption of raw and cooked (RC) garlic and garlic supplements, separately. The summary relative risks (RR) with 95%CI were calculated using fixed-effects or random-effects model depending on the heterogeneity among studies. A total of 5 prospective cohort studies were identified. In contrast to the previous meta-analysis, no significant associations were found between consumption of RC garlic (RR: 1.06; 95%CI: 0.95-1.19) or garlic supplements (RR: 1.12; 95%CI: 0.96-1.31) and risk of colorectal cancer. A non-significant protective effect of garlic supplement intake against colorectal cancer was observed in females (RR: 0.84; 95%CI: 0.64-1.11), but the opposite was the case in males (RR: 1.24; 95%CI: 0.96-1.59). Consumption of RC garlic or garlic supplements is not significantly associated with reduced colorectal cancer risk.
Liu, Xiao; Meng, Qingyang; Xi, Qiulei; Zhuang, Qiulin; Han, Yusong; Gao, Ying; Ding, Qiurong; Wu, Guohao
Background and Objectives Consumption of dietary fat has been reported to be associated with gastric cancer risk, but the results of epidemiologic studies remain inconsistent. We conducted a meta-analysis to summarize the evidence regarding the association between dietary fat intake and gastric cancer risk. Methods A comprehensive search of PubMed and EMBASE was performed to identify observational studies providing quantitative estimates between dietary fat and gastric cancer risk. Random effects model was used to calculate the summary relative risk(SRR) in the highest versus lowest analysis. Categorical dose-response analysis was conducted to quantify the association between dietary fat intake and gastric cancer risk. Heterogeneity among studies was evaluated using I2 and tau2(between study variance)statistics. Subgroup analysis and publication bias analysis were also performed. Results Twenty-two articles were included in the meta-analysis. The SRR for gastric cancer was 1.18 for individuals with highest intake versus lowest intake of total fat (95% confidence interval [CI]: 0.999–1.39; n = 28; Pgastric cancer risk were observed. Conclusions Our results suggest that intake of total fat is potentially positively associated with gastric cancer risk, and specific subtypes of fats account for different effects. However, these findings should be confirmed by further well-designed cohort studieswith detailed dietary assessments and strict control of confounders. PMID:26402223
Hwang, Ye Won; Kim, Soo Young; Jee, Sun Ha; Kim, Youn Nam; Nam, Chung Mo
Soybean products have been suggested to have a chemo preventive effect against prostate cancer. The aim of this study was to provide a comprehensive meta-analysis on the extent of the possible association between soy-based food consumption and the risk of prostate cancer. Five cohort studies and 8 case-control studies were identified using MEDLINE, EMBASE, CINAHL, Korea Medical Database, KoreaMed, Korean studies Information Service System, Japana Centra Revuo Medicina, China National Knowledge Infrastructure, and a manual search. Summary odds ratios (ORs) comparing high versus low categories of soybean consumptions were calculated on the basis of the random effect model. We analyzed the associations based on the different types of soybean consumptions. The summary ORs (95% CI) for total soy foods were 0.69 (CI = 0.57-0.84) and 0.75 (CI = 0.62-0.89) for nonfermented soy foods. Among individual soy foods, only tofu yielded a significant value of 0.73 (CI = 0.57-0.92). Consumption of soybean milk, miso, or natto did not significantly reduce the risk of prostate cancer. Genistein and daidzein were associated with a lower risk of prostate cancer. This systematic review suggests that soy food consumption could lower the risk of prostate cancer. This conclusion, however, should be interpreted with caution because various biases can affect the results of a meta-analysis.
Hidayat, Khemayanto; Du, Xuan; Zou, Sheng-Yi; Shi, Bi-Min
Globally, kidney cancer is the twelfth most common cancer, accounting for 337 860 cases recorded in 2012. By 2020, this number has been estimated to reach 412 929 or increase by 22%. Over the past few decades, a number of prospective studies have investigated the association between blood pressure (BP) and risk of kidney cancer, using either recorded BP levels or reported hypertension as the principal exposure variable. However, the relation of BP to kidney cancer remains incompletely understood, and the data on sex-specific differences in risk estimates have been inconsistent. PubMed and Web of Science databases were searched for studies assessing the association between BP and kidney cancer through July 2016. The summary relative risk with 95% confidence intervals was calculated using a random-effects model. A total of 18 prospective studies with 8097 kidney cancer cases from 3 628 479 participants were included in our meta-analysis. History of hypertension was associated with 67% increased risk of kidney cancer. Significant heterogeneity and evidence of publication bias were observed. However, the results remain unchanged after introducing the trim and fill method to correct the publication bias. Accordingly, each 10-mmHg increase in SBP and DBP was associated with 10 and 22% increased risk of kidney cancer. Collectively, the present meta-analysis of 18 prospective studies provides further support for a positive association between hypertension and kidney cancer risk.
Zhu, Shengjie; Shao, Bin; Hao, Yaoyao; Li, Zongxian; Liu, Houqiang; Li, Hong; Wang, Ming; Wang, Kai
Ghrelin was associated with several of cancers. The conflict results of SNPs with GHRL and GHSR gene were demonstrated in different studies. Thus, this meta-analysis is to evaluate the associations. Systematic literature search was done on PubMed database up to October 2013. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association by a fixed-effect model and a random-effect model. A total of 7 studies, which included 3 studies for breast cancer, 2 for colorectal cancer, 1 for hepatocellular carcinoma, 1 for esophageal cancer and 1 for Non-Hodgkin lymphoma. When analyzed all the GHRL SNPs with all kinds of cancers, there was significantly difference with cancer patients compared with controls (Recessive model: OR 0.938, 95% CI 0.890-0.989, p=0.017), while no significant difference was existed in the additive model (OR 0.9903, 95% CI 0.957-1.024, p=0.558) and dominant model (OR 1.014, 95% CI 0.970-1.061, p=0.536). When analyzed all the GHSR SNPs with all kinds of cancers, no significant difference was observed. Our results suggest that the SNP with GHRL and GHSR might be weaker association with cancer risk, especially with breast cancer risk.
Jiang, Gengxi; Li, Bailing; Liao, Xiaohong; Zhong, Chongjun
Mixed results regarding the association between white meat (including poultry and fish) intake and the risk of esophageal cancer (EC) have been reported. We performed a meta-analysis to provide a quantitative assessment of this association. Relevant studies were identified in MEDLINE until December 31, 2012. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were pooled with a random-effects model. A total of 20 articles, including 3990 cases with EC, were included in this meta-analysis. Compared to individuals with the lowest level of fish intake, individuals with the highest fish intake were found to have reduced risk of EC (SRRs = 0.69; 95% CIs: 0.57-0.85), while poultry intake was not associated with EC (SRRs = 0.83; 95% CIs: 0.62-1.12). Total fish consumption is associated with reduced esophageal squamous cell carcinoma (ESCC) risk, while poultry consumption was not associated with ESCC risk. Additionally, neither poultry nor fish consumption was associated with esophageal adenocarcinoma risk. Our results suggest that fish consumption may have a potential role in EC prevention, while poultry intake has no effect. However, because the majority of data was from case-control studies, further well-designed prospective studies are warranted. © 2013 Wiley Publishing Asia Pty Ltd.
Roloff, Verena; Higgins, Julian PT; Sutton, Alex J
Systematic reviews often provide recommendations for further research. When meta-analyses are inconclusive, such recommendations typically argue for further studies to be conducted. However, the nature and amount of future research should depend on the nature and amount of the existing research. We propose a method based on conditional power to make these recommendations more specific. Assuming a random-effects meta-analysis model, we evaluate the influence of the number of additional studies, of their information sizes and of the heterogeneity anticipated among them on the ability of an updated meta-analysis to detect a prespecified effect size. The conditional powers of possible design alternatives can be summarized in a simple graph which can also be the basis for decision making. We use three examples from the Cochrane Database of Systematic Reviews to demonstrate our strategy. We demonstrate that if heterogeneity is anticipated, it might not be possible for a single study to reach the desirable power no matter how large it is. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22786670
Lupoli, Roberta; Ambrosino, Pasquale; Tortora, Anna; Barba, Livia; Lupoli, Gelsy Arianna; Di Minno, Matteo Nicola Dario
Several studies reported an increased cardiovascular (CV) risk in Cushing's syndrome (CS). We performed a meta-analysis on the impact of CS on major markers of atherosclerosis. Studies on intima-media thickness (IMT), carotid plaques prevalence, and flow-mediated dilation (FMD) in CS patients and controls were searched in the PubMed, Web of Science, Scopus, and EMBASE. Differences between cases and controls were expressed as mean difference (MD) with 95% confidence intervals (95%CI) for continuous variables, and as Odds Ratio (OR) with 95%CI for dichotomous variables. Fourteen studies (332 CS, 462 controls) were included. Compared with controls, CS patients showed higher IMT (MD: 0.20 mm; 95% CI: 0.12, 0.28; p Cushing's syndrome (CS). In the present meta-analysis we demonstrated that CS is associated with an increased intima-media thickness, higher prevalence of carotid plaques, and lower flow-mediated dilation as compared with controls. These data consistently suggest the need for a strict monitoring of early signs of subclinical atherosclerosis in CS patients.
Full Text Available Introduction. Depression is one of the four major diseases in the world and is the most common cause of disability from diseases. The aim of this study is to estimate the prevalence of depression among Iranian university students using meta-analysis method. Materials and Methods. Keyword depression was searched in electronic databases such as PubMed, Scopus, MAGIran, Medlib, and SID. Data was analyzed using meta-analysis (random-effects model. Heterogeneity of studies was assessed using the I2 index. Data was analyzed using STATA software Ver.10. Results. In 35 studies conducted in Iran from 1995 to 2012 with sample size of 9743, prevalence of depression in the university students was estimated to be 33% (95% CI: 32–34. The prevalence of depression among boys was estimated to be 28% (95% CI: 26–30, among girls 23% (95% CI: 22–24, single students 39% (95% CI: 37–41, and married students 20% (95% CI: 17–24. Metaregression model showed that the trend of depression among Iranian students was flat. Conclusions. On the whole, depression is common in university students with no preponderance between males and females and in single students is higher than married ones.
Iniesta-Sepúlveda, Marina; Rosa-Alcázar, Ana I; Sánchez-Meca, Julio; Parada-Navas, José L; Rosa-Alcázar, Ángel
A meta-analysis on the efficacy of cognitive-behavior-family treatment (CBFT) on children and adolescents with obsessive-compulsive disorder (OCD) was accomplished. The purposes of the study were: (a) to estimate the effect magnitude of CBFT in ameliorating obsessive-compulsive symptoms and reducing family accommodation on pediatric OCD and (b) to identify potential moderator variables of the effect sizes. A literature search enabled us to identify 27 studies that fulfilled our selection criteria. The effect size index was the standardized pretest-postest mean change index. For obsessive-compulsive symptoms, the adjusted mean effect size for CBFT was clinically relevant and statistically significant in the posttest (d adj =1.464). For family accommodation the adjusted mean effect size was also positive and statistically significant, but in a lesser extent than for obsessive-compulsive symptoms (d adj =0.511). Publication bias was discarded as a threat against the validity of the meta-analytic results. Large heterogeneity among effect sizes was found. Better results were found when CBFT was individually applied than in group (d + =2.429 and 1.409, respectively). CBFT is effective to reduce obsessive-compulsive symptoms, but offers a limited effect for family accommodation. Additional modules must be included in CBFT to improve its effectiveness on family accommodation. Copyright © 2017 Elsevier Ltd. All rights reserved.
I. Marenholz (Ingo); J. Esparza-Gordillo (Jorge); F. Rüschendorf (Franz); A. Bauerfeind (Anja); D.P. Strachan (David P.); B.D. Spycher (Ben D.); H. Baurecht (Hansjörg); P. Margaritte-Jeannin (Patricia); A. Sääf (Annika); M. Kerkhof (Marjan); M. Ege (Markus); S. Baltic (Svetlana); J. Matheson; J. Li (Jin); S. Michel (Sven); W.Q. Ang (Wei Q.); W.L. McArdle (Wendy); A. Arnold (Andreas); G. Homuth (Georg); F. Demenais (Florence); E. Bouzigon (Emmanuelle); C. Söderhäll (Cilla); G. Pershagen (Göran); J.C. de Jongste (Johan); D.S. Postma (Dirkje); C. Braun-Fahrländer (Charlotte); E. Horak (Elisabeth); L.M. Ogorodova (Ludmila M.); V.P. Puzyrev (Valery P.); E.Y. Bragina (Elena Yu); T.J. Hudson (Thomas); C. Morin (Charles); D.L. Duffy (David); G.B. Marks (Guy B.); C. Robertson; G.W. Montgomery (Grant); A.W. Musk (Arthur); P.J. Thompson (Philip); N.G. Martin (Nicholas); A.L. James (Alan); P.M.A. Sleiman (Patrick); E. Toskala (Elina); P.M. Rodríguez; R. Fölster-Holst (R.); A. Franke (Andre); W. Lieb (Wolfgang); C. Gieger (Christian); A. Heinzmann (Andrea); E. Rietschel (Ernst); M. Keil (Mark); S. Cichon (Sven); M.M. Nöthen (Markus M.); C.E. Pennell (Craig); P.D. Sly; C.O. Schmidt (Carsten Oliver); A. Matanovic (Anja); V. Schneider (Valentin); M. Heinig (Matthias); N. Hübner (Norbert); P.G. Holt (Patrick); S. Lau (Susanne); M. Kabesch (Michael); S. Weidinger (Stefan); H. Hakonarson (Hakon); M.A. Ferreira (Manuel); C. Laprise (Catherine); M.B. Freidin (M.); J. Genuneit (Jon); G.H. Koppelman (Gerard); E. Melén (Erik); M.-H. Dizier; A.J. Henderson (A. John); Y.-A. Lee (Young-Ae)
textabstractEczema often precedes the development of asthma in a disease course called the a 'atopic march'. To unravel the genes underlying this characteristic pattern of allergic disease, we conduct a multi-stage genome-wide association study on infantile eczema followed by childhood asthma in 12
Lundstrøm, L H; Vester-Andersen, M; Møller, Ann
searches. The pooled estimates from the meta-analyses were calculated based on a random-effects model and a summary receiver operating curve. Meta-regression analyses were performed to explore sources of possible heterogeneity between the studies. The summary receiver operating curve demonstrated an area...
Cheng, Fengrui; Dai, Shuiping; Wang, Chiyi; Zeng, Shaoxue; Chen, Junjie; Cen, Ying
Aesthetic breast implant augmentation surgery is the most popular plastic surgery worldwide. Many women choose to receive breast implants during their reproductive ages, although the long-term effects are still controversial. Research aim: We conducted a meta-analysis to assess the influence of aesthetic breast augmentation on breastfeeding. We also compared the exclusive breastfeeding rates of periareolar versus inframammary incision. A systematic search for comparative studies about breast implants and breastfeeding was performed in PubMed, MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, ScienceDirect, Scopus, and Web of Science through May 2018. Meta-analysis was conducted with a random-effects model (or fixed effects, if heterogeneity was absent). Four cohorts and one cross-sectional study were included. There was a significant reduction in the exclusive breastfeeding rate for women with breast implants compared with women without implants, pooled relative risk = 0.63, 95% confidence interval [0.46, 0.86], as well as the breastfeeding rate, pooled relative risk = 0.88, 95% confidence interval [0.81, 0.95]. There was no evidence that periareolar incision was associated with a reduction in the exclusive breastfeeding rate, pooled relative risk = 0.84, 95% confidence interval [0.45, 1.58]. Participants with breast implants are less likely to establish breastfeeding, especially exclusive breastfeeding. Periareolar incision does not appear to reduce the exclusive breastfeeding rate.
Full Text Available Simultaneous analysis of genetic associations with multiple phenotypes may reveal shared genetic susceptibility across traits (pleiotropy. For a locus exhibiting overall pleiotropy, it is important to identify which specific traits underlie this association. We propose a Bayesian meta-analysis approach (termed CPBayes that uses summary-level data across multiple phenotypes to simultaneously measure the evidence of aggregate-level pleiotropic association and estimate an optimal subset of traits associated with the risk locus. This method uses a unified Bayesian statistical framework based on a spike and slab prior. CPBayes performs a fully Bayesian analysis by employing the Markov Chain Monte Carlo (MCMC technique Gibbs sampling. It takes into account heterogeneity in the size and direction of the genetic effects across traits. It can be applied to both cohort data and separate studies of multiple traits having overlapping or non-overlapping subjects. Simulations show that CPBayes can produce higher accuracy in the selection of associated traits underlying a pleiotropic signal than the subset-based meta-analysis ASSET. We used CPBayes to undertake a genome-wide pleiotropic association study of 22 traits in the large Kaiser GERA cohort and detected six independent pleiotropic loci associated with at least two phenotypes. This includes a locus at chromosomal region 1q24.2 which exhibits an association simultaneously with the risk of five different diseases: Dermatophytosis, Hemorrhoids, Iron Deficiency, Osteoporosis and Peripheral Vascular Disease. We provide an R-package 'CPBayes' implementing the proposed method.
Hovdenak, N; Sørbye, H; Dahl, O
During pelvic radiotherapy, many patients develop radiation-induced gastrointestinal symptoms, which may interfere with treatment. Prophylaxis during radiotherapy should ideally prevent acute reaction and the development of delayed injury. Sucralfate, an aluminium sucrose octasulphate, has been used for acute and delayed radiation side-effects. However, conflicting results have been published. We report here a prospective, randomised, placebo-controlled study of prophylactic sucralfate during pelvic radiotherapy. In addition, a meta-analysis of available data from the literature has been carried out. Fifty-one patients with localised pelvic tumours scheduled for curative conformal pelvic radiotherapy (total dose 64-70 Gy over 6.5-7 weeks in 2 Gy daily fractions) were included. Peroral sucralfate 2 g three times daily, or identically appearing placebo tablets, was given during the course of radiotherapy. Symptom registration, endoscopy and biopsies were carried out immediately before radiotherapy, 2 weeks and 6 weeks into the treatment course, and 2 weeks after completing radiotherapy. Mucosal cup forceps biopsies were obtained through a rigid proctoscope. Graded endoscopic appearance and quantitative histology were registered. On the basis of previously published negative reports, an unplanned interim analysis of 44 evaluable patients showed significantly increased diarrhoea in the sucralfate group and the trial was stopped. No difference was seen in other symptoms, endoscopic appearance or histology. A meta-analysis comprising five published studies showed no statistically significant beneficial effect of sucralfate on acute symptoms. Sucralfate cannot be recommended for prophylaxis of acute radiation proctopathy and may even worsen the symptoms.
Marenholz, Ingo; Esparza-Gordillo, Jorge; Rüschendorf, Franz; Bauerfeind, Anja; Strachan, David P; Spycher, Ben D; Baurecht, Hansjörg; Margaritte-Jeannin, Patricia; Sääf, Annika; Kerkhof, Marjan; Ege, Markus; Baltic, Svetlana; Matheson, Melanie C; Li, Jin; Michel, Sven; Ang, Wei Q; McArdle, Wendy; Arnold, Andreas; Homuth, Georg; Demenais, Florence; Bouzigon, Emmanuelle; Söderhäll, Cilla; Pershagen, Göran; de Jongste, Johan C; Postma, Dirkje S; Braun-Fahrländer, Charlotte; Horak, Elisabeth; Ogorodova, Ludmila M; Puzyrev, Valery P; Bragina, Elena Yu; Hudson, Thomas J; Morin, Charles; Duffy, David L; Marks, Guy B; Robertson, Colin F; Montgomery, Grant W; Musk, Bill; Thompson, Philip J; Martin, Nicholas G; James, Alan; Sleiman, Patrick; Toskala, Elina; Rodriguez, Elke; Fölster-Holst, Regina; Franke, Andre; Lieb, Wolfgang; Gieger, Christian; Heinzmann, Andrea; Rietschel, Ernst; Keil, Thomas; Cichon, Sven; Nöthen, Markus M; Pennell, Craig E; Sly, Peter D; Schmidt, Carsten O; Matanovic, Anja; Schneider, Valentin; Heinig, Matthias; Hübner, Norbert; Holt, Patrick G; Lau, Susanne; Kabesch, Michael; Weidinger, Stefan; Hakonarson, Hakon; Ferreira, Manuel A R; Laprise, Catherine; Freidin, Maxim B; Genuneit, Jon; Koppelman, Gerard H; Melén, Erik; Dizier, Marie-Hélène; Henderson, A John; Lee, Young Ae
Eczema often precedes the development of asthma in a disease course called the 'atopic march'. To unravel the genes underlying this characteristic pattern of allergic disease, we conduct a multi-stage genome-wide association study on infantile eczema followed by childhood asthma in 12 populations including 2,428 cases and 17,034 controls. Here we report two novel loci specific for the combined eczema plus asthma phenotype, which are associated with allergic disease for the first time; rs9357733 located in EFHC1 on chromosome 6p12.3 (OR 1.27; P=2.1 × 10(-8)) and rs993226 between TMTC2 and SLC6A15 on chromosome 12q21.3 (OR 1.58; P=5.3 × 10(-9)). Additional susceptibility loci identified at genome-wide significance are FLG (1q21.3), IL4/KIF3A (5q31.1), AP5B1/OVOL1 (11q13.1), C11orf30/LRRC32 (11q13.5) and IKZF3 (17q21). We show that predominantly eczema loci increase the risk for the atopic march. Our findings suggest that eczema may play an important role in the development of asthma after eczema.
Full Text Available Abstract Background Complex or heterogeneous data pose challenges for systematic review and meta-analysis. In recent years, a number of new methods have been developed to meet these challenges. This qualitative interview study aimed to understand researchers’ understanding of complexity and heterogeneity and the factors which may influence the choices researchers make in synthesising complex data. Methods We conducted interviews with a purposive sample of researchers (N = 19 working in systematic review or meta-analysis across a range of disciplines. We analysed data thematically using a framework approach. Results Participants reported using a broader range of methods and data types in complex reviews than in traditional reviews. A range of techniques are used to explore heterogeneity, but there is some debate about their validity, particularly when applied post hoc. Conclusions Technical considerations of how to synthesise complex evidence cannot be isolated from questions of the goals and contexts of research. However, decisions about how to analyse data appear to be made in a largely informal way, drawing on tacit expertise, and their relation to these broader questions remains unclear.
Lorenc, Theo; Felix, Lambert; Petticrew, Mark; Melendez-Torres, G J; Thomas, James; Thomas, Sian; O'Mara-Eves, Alison; Richardson, Michelle
Complex or heterogeneous data pose challenges for systematic review and meta-analysis. In recent years, a number of new methods have been developed to meet these challenges. This qualitative interview study aimed to understand researchers' understanding of complexity and heterogeneity and the factors which may influence the choices researchers make in synthesising complex data. We conducted interviews with a purposive sample of researchers (N = 19) working in systematic review or meta-analysis across a range of disciplines. We analysed data thematically using a framework approach. Participants reported using a broader range of methods and data types in complex reviews than in traditional reviews. A range of techniques are used to explore heterogeneity, but there is some debate about their validity, particularly when applied post hoc. Technical considerations of how to synthesise complex evidence cannot be isolated from questions of the goals and contexts of research. However, decisions about how to analyse data appear to be made in a largely informal way, drawing on tacit expertise, and their relation to these broader questions remains unclear.
Full Text Available The identification of genes associated with a given biological function in plants remains a challenge, although network-based gene prioritization algorithms have been developed for Arabidopsis thaliana and many non-model plant species. Nevertheless, these network-based gene prioritization algorithms have encountered several problems; one in particular is that of unsatisfactory prediction accuracy due to limited network coverage, varying link quality, and/or uncertain network connectivity. Thus a model that integrates complementary biological data may be expected to increase the prediction accuracy of gene prioritization. Towards this goal, we developed a novel gene prioritization method named RafSee, to rank candidate genes using a random forest algorithm that integrates sequence, evolutionary, and epigenetic features of plants. Subsequently, we proposed an integrative approach named RAP (Rank Aggregation-based data fusion for gene Prioritization, in which an order statistics-based meta-analysis was used to aggregate the rank of the network-based gene prioritization method and RafSee, for accurately prioritizing candidate genes involved in a pre-specific biological function. Finally, we showcased the utility of RAP by prioritizing 380 flowering-time genes in Arabidopsis. The ‘leave-one-out’ cross-validation experiment showed that RafSee could work as a complement to a current state-of-art network-based gene prioritization system (AraNet v2. Moreover, RAP ranked 53.68% (204/380 flowering-time genes higher than AraNet v2, resulting in an 39.46% improvement in term of the first quartile rank. Further evaluations also showed that RAP was effective in prioritizing genes-related to different abiotic stresses. To enhance the usability of RAP for Arabidopsis and non-model plant species, an R package implementing the method is freely available at http://bioinfo.nwafu.edu.cn/software.
Full Text Available BACKGROUND: Excision repair cross-complimentary group 1 (ERCC1 is an essential component of the nucleotide excision repair system that is responsible for repairing damaged DNA. Functional genetic variations in the ERCC1 gene may alter DNA repair capacity and modulate cancer risk. The putative roles of ERCC1 gene polymorphisms in lung cancer susceptibility have been widely investigated. However, the results remain controversial. OBJECTIVES: An updated meta-analysis was conducted to explore whether lung cancer risk could be attributed to the following ERCC1 polymorphisms: rs11615 (T>C, rs3212986 (C>A, rs3212961 (A>C, rs3212948 (G>C, rs2298881 (C>A. METHODS: Several major databases (MEDLINE, EMBASE and Scopus and the Chinese Biomedical database were searched for eligible studies. Crude odds ratios (ORs with 95% confidence intervals (CIs were used to measure the strength of associations. RESULTS: Sixteen studies with 10,106 cases and 13,238 controls were included in this meta-analysis. Pooled ORs from 11 eligible studies (8,215 cases vs. 11,402 controls suggested a significant association of ERCC1 rs11615 with increased risk for lung cancer (homozygous: CC versus TT, OR = 1.24, 95% CI: 1.04-1.48, P = 0.02. However, such an association was disproportionately driven by a single study. Removal of that study led to null association. Moreover, initial analyses suggested that ERCC1 rs11615 exerts a more profound effect on the susceptibility of non-smokers to lung cancer than that of smokers. Moreover, no statistically significant association was found between remaining ERCC1 polymorphisms of interest and lung cancer risk, except for rs3212948 variation (heterozygous: CG vs.GG, OR = 0.78, 95% CI: 0.67-0.90, P = 0.001; dominant: CG/CC vs.GG, OR = 0.79, 95% CI: 0.69-0.91, P = 0.001. CONCLUSION: Overall, this meta-analysis suggests that ERCC1 rs3212948 G>C, but not others, is a lung cancer risk-associated polymorphism. Carefully
Sapkota, Yadav; Steinthorsdottir, Valgerdur; Morris, Andrew P.
Endometriosis is a heritable hormone-dependent gynecological disorder, associated with severe pelvic pain and reduced fertility; however, its molecular mechanisms remain largely unknown. Here we perform a meta-analysis of 11 genome-wide association case-control data sets, totalling 17,045 endomet...
Durmaz, Aysegul; Komurcu, Nuran
Postpartum hemorrhage (PPH) is a leading cause of maternal death in low-income countries and the primary cause of approximately one of every four maternal deaths worldwide. The aim of this study was to determine the antenatal risk factors of PPH and its effects. The literature from nine databases was reviewed, and studies published between 2000 and 2012 were analyzed using terms such as "postpartum hemorrhage," "prevention of postpartum hemorrhage," and "management of postpartum hemorrhage." The full text of 1,061 articles was reviewed, and 29 studies were selected according to the inclusion criteria. Studies that determined bias using the funnel plot test were excluded, and 20 studies were included in the meta-analysis. The data were analyzed using Microsoft Office Excel 2010 and comprehensive meta-analysis. The meta-analysis included five studies and 1,286,752 women for maternal age, six studies and 607,822 women for body mass index, and six studies and 1,118,490 women for parity. The results of the analysis showed that body mass index ≥ 25.00 kg/m (OR = 1.43, 95% CI [1.40, 1.47]), primiparity of mothers (OR = 1.37, 95% CI [1.35, 1.40]), and hypertensive disorder in mothers (OR = 1.52, 95% CI [1.43, 1.61]) are risk factors for the development of PPH. No rela-tionship was found between maternal age ≥ 35 years and PPH (OR = 1.02, 95% CI [0.99, 1.04]). Midwives, obstetric nurses, and obstetricians should carefully evaluate mothers for the risk factors of PPH during the antepartum, intrapartum, and postpartum periods. Moreover, at-risk pregnant women should give birth in a unit with emergency initiative options. Future studies should examine relevant personal characteristics of mothers, as familiarity with the risk factors facilitates the management and treatment of PPH. Finally, meta-analyses should review more studies to detect risk factors more comprehensively.
Fu, Wenning; Wang, Chao; Zou, Li; Liu, Qiaoyan; Gan, Yong; Yan, Shijiao; Song, Fujian; Wang, Zhihong; Lu, Zuxun; Cao, Shiyi
An increasing amount of original studies suggested that exposure to noise could be associated with the risk of hypertension, but the results remain inconsistent and inconclusive. We aimed to synthesize available epidemiological evidence about the relationship between various types of noise and hypertension, and to explore the potential dose-response relationship between them in an up-to-date meta-analysis. We conducted a literature search of PubMed and Embase from these databases' inception through December 2016 to identify observational epidemiological studies examining the association between noise and risk of hypertension. A random effects model was used to combine the results of included studies. Dose-response meta-analysis was conducted to examine the potential dose-response relationship. In total, 32 studies (five cohort studies, one case-control study, and 26 cross-section studies) involving 264 678 participants were eligible for inclusion. Pooled result showed that living or working in environment with noise exposure was significantly associated with increased risk of hypertension (odds ratio 1.62; 95% confidence interval: 1.40-1.88). We found no evidence of a curve linear association between noise and risk of hypertension. A dose-response analysis suggested that, for an increment of per 10 dB(A) of noise, the combined odds ratio of hypertension was 1.06 (95% confidence interval: 1.04-1.08). Integrated epidemiological evidence supports the hypothesis that exposure to noise may be a risk factor of hypertension, and there is a positive dose-response association between them.
Full Text Available Observational studies of the relationship between hyperuricemia and the incidence of hypertension are controversial. We conducted a systematic review and meta-analysis to assess the association and consistency between uric acid levels and the risk of hypertension development.We searched MEDLINE, EMBASE, CBM (Chinese Biomedicine Database through September 2013 and reference lists of retrieved studies to identify cohort studies and nested case-control studies with uric acid levels as exposure and incident hypertension as outcome variables. Two reviewers independently extracted data and assessed study quality using Newcastle-Ottawa Scale. Extracted information included study design, population, definition of hyperuricemia and hypertension, number of incident hypertension, effect sizes, and adjusted confounders. Pooled relative risks (RRs and corresponding 95% confidence intervals (CIs for the association between hyperuricemia and risk of hypertension were calculated using a random-effects model.We included 25 studies with 97,824 participants assessing the association between uric acid and incident hypertension in our meta-analysis. The quality of included studies is moderate to high. Random-effects meta-analysis showed that hyperuricemia was associated with a higher risk of incident hypertension, regardless of whether the effect size was adjusted or not, whether the data were categorical or continuous as 1 SD/1 mg/dl increase in uric acid level (unadjusted: RR = 1.73, 95% CI 1.46∼2.06 for categorical data, RR = 1.22, 95% CI 1.03∼1.45 for a 1 SD increase; adjusted: RR = 1.48, 95% CI 1.33∼1.65 for categorical data, RR = 1.15, 95% CI 1.06∼1.26 for a 1 mg/dl increase, and the risk is consistent in subgroup analyses and have a dose-response relationship.Hyperuricemia may modestly increase the risk of hypertension incidence, consistent with a dose-response relationship.
Yao, Baodong; Yan, Yujie; Ye, Xianwu; Fang, Hong; Xu, Huilin; Liu, Yinan; Li, Sheran; Zhao, Yanping
Observational studies suggest an association between fruit and vegetables intake and risk of bladder cancer, but the results are controversial. We therefore summarized the evidence from observational studies in categorical, linear, and nonlinear, dose-response meta-analysis. Pertinent studies were identified by searching EMBASE and PubMed from their inception to August 2013. Thirty-one observational studies involving 12,610 cases and 1,121,649 participants were included. The combined rate ratio (RR, 95 % CI) of bladder cancer for the highest versus lowest intake was 0.83 (0.69-0.99) for total fruit and vegetables, 0.81 (0.70-0.93) for total vegetables, 0.77 (0.69-0.87) for total fruit, 0.84 (0.77-0.91) for cruciferous vegetables, 0.79 (0.68-0.91) for citrus fruits, and 0.74 (0.66-0.84) for yellow-orange vegetables. Subgroup analysis showed study design and gender as possible sources of heterogeneity. A nonlinear relationship was found of citrus fruits intake with risk of bladder cancer (P for nonlinearity = 0.018), and the RRs (95 % CI) of bladder cancer were 0.87 (0.78-0.96), 0.80 (0.67-0.94), 0.79 (0.66-0.94), 0.79 (0.65-0.96), and 0.79 (0.64-0.99) for 30, 60, 90, 120, and 150 g/day. A nonlinear relationship was also found of yellow-orange vegetable intake with risk of bladder cancer risk (P for nonlinearity = 0.033). Some evidence of publication bias was observed for fruit, citrus fruits, and yellow-orange vegetables. This meta-analysis supports the hypothesis that intakes of fruit and vegetables may reduce the risk of bladder cancer. Future well-designed studies are required to confirm this finding.
Schür, Remmelt R; Draisma, Luc W R; Wijnen, Jannie P; Boks, Marco P; Koevoets, Martijn G J C; Joëls, Marian; Klomp, Dennis W; Kahn, René S; Vinkers, Christiaan H
The inhibitory gamma-aminobutyric acid (GABA) system is involved in the etiology of most psychiatric disorders, including schizophrenia, autism spectrum disorder (ASD) and major depressive disorder (MDD). It is therefore not surprising that proton magnetic resonance spectroscopy ((1) H-MRS) is increasingly used to investigate in vivo brain GABA levels. However, integration of the evidence for altered in vivo GABA levels across psychiatric disorders is lacking. We therefore systematically searched the clinical (1) H-MRS literature and performed a meta-analysis. A total of 40 studies (N = 1,591) in seven different psychiatric disorders were included in the meta-analysis: MDD (N = 437), schizophrenia (N = 517), ASD (N = 150), bipolar disorder (N = 129), panic disorder (N = 81), posttraumatic stress disorder (PTSD) (N = 104), and attention deficit/hyperactivity disorder (ADHD) (N = 173). Brain GABA levels were lower in ASD (standardized mean difference [SMD] = -0.74, P = 0.001) and in depressed MDD patients (SMD = -0.52, P = 0.005), but not in remitted MDD patients (SMD = -0.24, P = 0.310) compared with controls. In schizophrenia this finding did not reach statistical significance (SMD = -0.23, P = 0.089). No significant differences in GABA levels were found in bipolar disorder, panic disorder, PTSD, and ADHD compared with controls. In conclusion, this meta-analysis provided evidence for lower brain GABA levels in ASD and in depressed (but not remitted) MDD patients compared with healthy controls. Findings in schizophrenia were more equivocal. Even though future (1) H-MRS studies could greatly benefit from a longitudinal design and consensus on the preferred analytical approach, it is apparent that (1) H-MRS studies have great potential in advancing our understanding of the role of the GABA system in the pathogenesis of psychiatric disorders. Hum Brain Mapp 37:3337-3352, 2016. © 2016 Wiley Periodicals
Barrett, Jeffrey C; Clayton, David G; Concannon, Patrick
Type 1 diabetes (T1D) is a common autoimmune disorder that arises from the action of multiple genetic and environmental risk factors. We report the findings of a genome-wide association study of T1D, combined in a meta-analysis with two previously published studies. The total sample set included 7......,514 cases and 9,045 reference samples. Forty-one distinct genomic locations provided evidence for association with T1D in the meta-analysis (P
Valipour, Ghazaleh; Saneei, Parvane; Esmaillzadeh, Ahmad
Although several observational studies have investigated the association between vitamin D status and schizophrenia, we are aware of no comprehensive meta-analysis in this regard. We aimed to conduct a systematic review and a meta-analysis of observational studies to summarize the available data on the association between serum vitamin D levels and schizophrenia. A systematic research on all published articles until October 2013 was conducted in PubMed, ISI (Web of science), SCOPUS, and Google Scholar. All observational studies that had measured serum vitamin D levels in schizophrenic patients were included in the systematic review. After considering exclusion criteria, we had 19 studies for the systematic review that were included in three separate meta-analyses: 1) a meta-analysis on mean levels of 25-hydroxyvitamin D [25(OH)D] (n = 13); 2) a meta-analysis on the prevalence of vitamin D deficiency (n = 8); 3) a meta-analysis on odds ratios (n = 8). Findings from a meta-analysis on means revealed that the overall mean difference in serum 25(OH)D levels between schizophrenic patients and control participants was -5.91 ng/mL [95% confidence interval (CI) -10.68, -1.14]. Subgroup analyses based on study design, the patient's hospitalization status, study quality, and study location did not explain between-study heterogeneity; however, type of biomarker assessed [25-hydroxyvitamin D3 vs 25-hydroxyvitamin D (D2 & D3)] could account for some degree of heterogeneity. RESULTS from the meta-analysis on the prevalence of vitamin D deficiency indicated that the overall prevalence of vitamin D deficiency in schizophrenic patients was 65.3% (95% CI 46.4%-84.2%). Findings from the meta-analysis on odds ratios indicated that vitamin D-deficient persons were 2.16 times (95% CI 1.32, 3.56) more likely to have schizophrenia than those with vitamin D sufficiency. No evidence of heterogeneity was detected. We found a strong association between vitamin D deficiency and schizophrenia
Liu, Xueying; Du, Xiaoyuan; Han, Guanying; Gao, Wenyuan
The epidemiological evidence for a dose-response relationship between tea consumption and risk of cognitive disorders is sparse. The aim of the study was to summarize the evidence for the association of tea consumption with risk of cognitive disorders and assess the dose-response relationship. We searched electronic databases of Pubmed, Embase, and Cochrane Library (from 1965 to Jan 19, 2017) for eligible studies that published in the international journals. A random-effects model was used to pool the most adjusted odds ratios (ORs) and the corresponding 95% confidence intervals (CIs). Seventeen studies involving 48,435 participants were included in our study. The meta-analysis showed that a higher tea consumption was associated with a significant reduction in the risk of cognitive disorders (OR=0.73, 95% CI: 0.65-0.82). When considering the specific types of tea consumption, the significantly inverse association is only found in green tea consumption (OR=0.64, 95% CI: 0.53-0.77) but not in black/oolong tea consumption (OR=0.75, 95% CI: 0.55-1.01). Dose-response meta-analysis indicated that tea consumption is linearly associated with a reduced risk of cognitive disorders. An increment of 100 ml/day, 300 ml/day, and 500 ml/day of tea consumption was associated with a 6% (OR=0.94, 95% CI: 0.92-0.96), 19% (OR=0.81, 95% CI: 0.74-0.88), and 29% (OR=0.71, 95% CI: 0.62-0.82) lower risk of cognitive disorders. Tea consumption is inversely and linearly related to the risk of cognitive disorders. More studies are needed to further confirm our findings.
Full Text Available Iron homeostasis dysregulation has been regarded as an important mechanism in neurodegenerative diseases. The H63D and C282Y polymorphisms in the HFE gene may be involved in the development of sporadic amyotrophic lateral sclerosis (ALS through the disruption of iron homeostasis. However, studies investigating the relationship between ALS and these two polymorphisms have yielded contradictory outcomes. We performed a meta-analysis to assess the roles of the H63D and C282Y polymorphisms of HFE in ALS susceptibility. PubMed, MEDLINE, EMBASE, and Cochrane Library databases were systematically searched to identify relevant studies. Strict selection criteria and exclusion criteria were applied. Odds ratios (ORs with 95% confidence intervals (CIs were used to assess the strength of associations. A fixed- or random-effect model was selected, depending on the results of the heterogeneity test. Fourteen studies were included in the meta-analysis (six studies with 1692 cases and 8359 controls for C282Y; 14 studies with 5849 cases and 13,710 controls for H63D. For the C282Y polymorphism, significant associations were observed in the allele model (Y vs C: OR=0.76, 95%CI=0.62-0.92, P=0.005 and the dominant model (YY+CY vs CC: OR=0.75, 95%CI=0.61-0.92, P=0.006. No associations were found for any genetic model for the H63D polymorphism. The C282Y polymorphism in HFE could be a potential protective factor for ALS in Caucasians. However, the H63D polymorphism does not appear to be associated with ALS.
DeSmet, Ann; Shegog, Ross; Van Ryckeghem, Dimitri; Crombez, Geert; De Bourdeaudhuij, Ilse
Serious games may be effective in promoting sexual health behavior. Their confidential nature may encourage users to discuss sensitive sexuality topics. Furthermore, they can tailor messages to the individual's needs and may be intrinsically motivating. This meta-analysis investigates the effectiveness of interventions for sexual health promotion that use serious games. A database search was conducted in PubMed, Web of Science, CINAHL, and PsycINFO for publications before the end of July 2013. Serious digital games studies measuring effects on behavior or its determinants, using a control condition, allowing the calculation of an effect size (Hedges' g, random-effects model) were included. Seven game studies for sexual health promotion were included. These showed positive effects on determinants (g=0.242; 95 percent confidence interval, 0.129, 0.356), albeit of small effect size. The effects on behavior, measured in only two studies, were not significant (g=0.456; 95 percent confidence interval, -0.649, 1.561). Most games did not use many game features that are considered to be immersive or enhancing flow. Instead, there was a strong reliance on pure gamification features, such as rewards and feedback. The effectiveness of the next generation of games may be enhanced by building on the behavioral change and educational gaming literatures (e.g., using role-play and simulation game formats, individual tailoring, offering adaptation in the difficulty of the challenge, and amount and timing of the feedback). There is a need for studies with rigorous evaluations of game effectiveness, longer-term follow-up, and using measures of behavior rather than merely their determinants.
Full Text Available Kai Bai,* Qiucheng Cai,* Yi Jiang, Lizhi Lv Department of Hepatobiliary Surgery, Fuzong Clinical College, Fujian Medical University, Fuzhou, People’s Republic of China *These authors contributed equally to this work Abstract: Growing evidence has shown that coffee consumption is inversely related with the risk of hepatocellular carcinoma. It is suggested that caffeine maintains strong antioxidative activity. With this property, coffee intake may lead to the inhibition of cell proliferation of liver cancer cells; also, some compounds contained in coffee can reduce the genotoxicity of aflatoxin B1 in vitro and lower the damage caused by some carcinogens. A computerized search was performed in PubMed to identify relevant articles published before August 2015. Eleven relevant studies were included with a total of 2,795 cases and 340,749 control subjects. According to the meta-analysis we performed, the pooled odds ratio (OR from all included studies was 0.49 (95% confidence interval [CI] =0.46–0.52. The subgroup analysis indicated that the pooled ORs for Asian studies and other populations were 0.27 (95% CI =0.23–0.31 and 0.82 (95% CI =0.77–0.87, respectively. The overall pooled OR for high consumption was decreased to 0.21 (95% CI =0.18–0.25 and significance was observed. Among other populations, the pooled OR of subjects with high coffee consumption was 0.65 (95% CI =0.56–0.73 compared to the nondrinker. The corresponding OR of five Asian studies was 0.13 (95% CI =0.09–0.17. The findings from this meta-analysis further confirmed the inverse association between the coffee consumption and hepatocellular carcinoma risk with quantitative evidence. The protective effect can be detected among healthy population and patients with chronic liver diseases, and the consumption can also prevent the development of liver cirrhosis. Keywords: hepatocarcinogenesis, meta-analysis, coffee, antioxidant
Chrissa G. Tsiara
Mar 13, 2018 ... a meta-analysis of case–control studies was conducted. Univariate and ...... recent hepatitis C virus: potential benefit for ribavirin use in. HCV/HIV ... C/G polymorphism in breast pathologies and in HIV-infected patients.
Cong, Y J; Gan, Y; Sun, H L; Deng, J; Cao, S Y; Xu, X; Lu, Z X
Sedentary behaviour is ubiquitous in modern society. Emerging studies have focused on the health consequences of sedentary behaviour, including colorectal cancer, but whether sedentary behaviour is associated with the risks of colon and rectal cancer remains unclear. No systematic reviews have applied quantitative techniques to independently compute summary risk estimates. We aimed to conduct a meta-analysis to investigate this issue. We searched PubMed, Embase, and Google Scholar databases up to May 2013 to identify cohort and case-control studies that evaluated the association between sedentary behaviour and colon or rectal cancer. A random-effect model was used to pool the results of included studies. Publication bias was assessed by using Begg's funnel plot. Twenty-three studies with 63 reports were included in our meta-analysis. These groups included 4,324,462 participants (27,231 colon cancer cases and 13,813 rectal cancer cases). Sedentary behaviour was significantly associated with colon cancer (relative risk (RR): 1.30, 95% confidence interval (CI): 1.22-1.39) but did not have a statistically significant association with rectal cancer (RR 1.05, 95% CI, 0.98-1.13). Subgroup analyses suggested that the odds ratio (OR) of colon cancer was 1.46 (95% CI: 1.22-1.68) in the case-control studies, and the RR was 1.27 (95% CI: 1.18-1.36) in the cohort studies, the OR of rectal cancer was 1.06 (95% CI: 0.85-1.33) in the case-control studies, and the RR was 1.06 (95% CI, 1.01-1.12) in the cohort studies. Sedentary behaviour is associated with an increased risk of colon cancer. Subgroup analyses suggest a positive association between sedentary behaviour and risk of rectal cancer in cohort studies. Reducing sedentary behaviour is potentially important for the prevention of colorectal cancer.
Larsson, Susanna C; Åkesson, Agneta; Gigante, Bruna; Wolk, Alicja
To examine whether chocolate consumption is associated with a reduced risk of ischaemic heart disease, we used data from a prospective study of Swedish adults and we performed a meta-analysis of available prospective data. The Swedish prospective study included 67 640 women and men from the Cohort of Swedish Men and the Swedish Mammography Cohort who had completed a food-frequency questionnaire and were free of cardiovascular disease at baseline. Myocardial infarction (MI) cases were ascertained through linkage with the Swedish National Patient and Cause of Death Registers. PubMed and EMBASE databases were searched from inception until 4 February 2016 to identify prospective studies on chocolate consumption and risk of ischaemic heart disease. The results from eligible studies were combined using a random-effects model. During follow-up (1998-2010), 4417 MI cases were ascertained in the Swedish study. Chocolate consumption was inversely associated with MI risk. Compared with non-consumers, the multivariable relative risk for those who consumed ≥3-4 servings/week of chocolate was 0.87 (95% CI 0.77 to 0.98; p for trend =0.04). Five prospective studies on chocolate consumption and ischaemic heart disease were identified. Together with the Swedish study, the meta-analysis included six studies with a total of 6851 ischaemic heart disease cases. The overall relative risk for the highest versus lowest category of chocolate consumption was 0.90 (95% CI 0.82 to 0.97), with little heterogeneity among studies (I(2)=24.3%). Chocolate consumption is associated with lower risk of MI and ischaemic heart disease. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Kuiper, Jisca S; Zuidersma, Marij; Zuidema, Sytse U; Burgerhof, Johannes Gm; Stolk, Ronald P; Oude Voshaar, Richard C; Smidt, Nynke
Although poor social relationships are assumed to contribute to cognitive decline, meta-analytic approaches have not been applied. Individual study results are mixed and difficult to interpret due to heterogeneity in measures of social relationships. We conducted a systematic review and meta-analysis to investigate the relation between poor social relationships and cognitive decline. MEDLINE, Embase and PsycINFO were searched for longitudinal cohort studies examining various aspects of social relationships and cognitive decline in the general population. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled using random effects meta-analysis. Sources of heterogeneity were explored and likelihood of publication bias was assessed. We stratified analyses according to three aspects of social relationships: structural, functional and a combination of these. We identified 43 articles. Poor social relationships predicted cognitive decline; for structural (19 studies): pooled OR: 1.08 (95% CI: 1.05-1.11); functional (8 studies): pooled OR: 1.15 (95% CI: 1.00-1.32); and combined measures (7 studies): pooled OR: 1.12 (95% CI: 1.01-1.24). Meta-regression and subgroup analyses showed that the heterogeneity could be explained by the type of social relationship measurement and methodological quality of included studies. Despite heterogeneity in study design and measures, our meta-analyses show that multiple aspects of social relationships are associated with cognitive decline. As evidence for publication bias was found, the association might be overestimated and should therefore be interpreted with caution. Future studies are needed to better define the mechanisms underlying these associations. Potential causality of this prognostic association should be examined in future randomized controlled studies. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.
Newman, Anne B; Walter, Stefan; Lunetta, Kathryn L
BACKGROUND: Genome-wide association studies (GWAS) may yield insights into longevity. METHODS: We performed a meta-analysis of GWAS in Caucasians from four prospective cohort studies: the Age, Gene/Environment Susceptibility-Reykjavik Study, the Cardiovascular Health Study, the Framingham Heart S...
Yang, Ximeng; Lu, Jun; Wang, Junjie; Wang, Lijun; Qi, Peng; Hu, Shen; Chen, Kunpeng; Wang, Daming
Carotid stenosis (CS) and intracranial aneurysms (IAs) may concur in one person. We studied the prevalence of IAs in CS patients in our retrospectively collected database and systematically reviewed this issue. Five hundred and fifty-seven CS (≥50%) patients confirmed by DSA in our hospital from 2010-06 to 2015-06 were screened for coexistent IAs. After searching the related literatures from English and Chinese journal literature databases, a meta-analysis was performed to pool the prevalence of CS with coexistent IAs. Subgroup analyses were performed to explore the causes of heterogeneity among studies. IAs were detected in 98(17.0%) out of the 577 CS patients. 12 literatures and the present study including a total of 6965 CS patients and 446 cases with coexistent IAs. The pooled prevalence of CS with coexistent IAs was 6.3% (95%CI: 4.2-8.3%) in all the CS patients. The pooled RR for female to male CS patients to have coexistent IAs was 1.67 (95%CI: 1.34-2.08, P = 0.000). 3 studies and the present study were carried out in Asian countries with a pooled prevalence of 10.8% (95%CI: 5.3-16.3%); 6 studies in European countries with 3.0% (95%CI: 2.2-3.7%); and 3 studies in USA with 6.0% (95%CI: 2.2-9.7%). There was a statistically significant difference between the three subgroups (P IAs in CS patients seems higher in our clinical study and the meta-analysis than in the general population and previously reported. The eastern and the women CS patients have a higher risk for coexistent IAs. Copyright © 2018 Elsevier Ltd. All rights reserved.
Full Text Available Several epidemiological studies have determined the associations between coffee intake level and skin cancer risk; however, the results were not yet conclusive. Herein, we conducted a systematic review and meta-analysis of the cohort and case-control studies for the association between coffee intake level and malignant melanoma (MM risk.Studies were identified through searching the PubMed and MEDLINE databases (to November, 2015. Study-specific risk estimates were pooled under the random-effects model.Two case-control studies (846 MM patients and 843 controls and five cohort studies (including 844,246 participants and 5,737 MM cases were identified. For caffeinated coffee, the pooled relative risk (RR of MM was 0.81 [95% confidential interval (95% CI = 0.68-0.97; P-value for Q-test = 0.003; I2 = 63.5%] for those with highest versus lowest quantity of intake. In the dose-response analysis, the RR of MM was 0.955 (95% CI = 0.912-0.999 for per 1 cup/day increment of caffeinated coffee consumption and linearity dose-response association was found (P-value for nonlinearity = 0.326. Strikingly, no significant association was found between the decaffeinated coffee intake level and MM risk (pooled RR = 0.92, 95% CI = 0.81-1.05; P-value for Q-test = 0.967; I2 = 0%; highest versus lowest quantity of intake.This meta-analysis suggested that caffeinated coffee might have chemo-preventive effects against MM but not decaffeinated coffee. However, larger prospective studies and the intervention studies are warranted to confirm these findings.
Full Text Available Child gender has been proved to affect toddlers’/children’s language development in several studies, but its effect was not found to be stable across different ages or various aspects of language ability. The effect of gender on toddler’s, children’s and adolescents’ language ability was examined in the present meta-analysis of ten Slovenian studies (nine cross-sectional studies and one longitudinal study. The ten studies were published between 2004 and 2016 and included a total of 3,657 toddlers, children and adolescents, aged from 8 months to 15 years. The language outcome measures refer to different aspects of language ability, including vocabulary, mean length of utterance, sentence complexity, language expression and comprehension, storytelling ability and metalinguistic awareness. Across the studies, language ability was assessed using different approaches and instruments, most of which were standardised on samples ofSlovenian speaking children. Based on the reported arithmetic means and standard deviations, the effect sizes of gender for each of the included studies were calculated, as well as the average effect size of gender across the different studies. The findings of the meta-analysis showed that the effect size of gender on toddlers’/children’s/adolescents’ language largely depended on their age and the aspect of language measured. The effect sizes increased with children’s increasing age. All significant effects proved to be in favour of girls. The findings were interpreted in relation to the characteristics of language development and social cultural factors that can contribute to gender differences in language ability.
Hsiao, Jenn-Ren; Ou, Chun-Yen; Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S
Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. THE CURRENT PAPER REPORTS RESULTS FROM: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27-0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63-0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40-0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54-0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81-1.18). These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC.
Full Text Available BACKGROUND: Several studies have shown that erectile dysfunction (ED influences the risk of cardiovascular events (CV events. However, a meta-analysis of the overall risk of CV events associated with ED in patients with diabetes has not been performed. METHODOLOGY/PRINCIPAL FINDINGS: We searched MEDLINE and the Cochrane Library for pertinent articles (including references published between 1951 and April 22, 2012. English language reports of original observational cohort studies and cross-sectional studies were included. Pooled effect estimates were obtained by random effects meta-analysis. A total of 3,791 CV events were reported in 3 cohort studies and 9 cross-sectional studies (covering 22,586 subjects. Across the cohort studies, the overall odds ratio (OR of diabetic men with ED versus those without ED was 1.74 (95% confidence interval [CI]: 1.34-2.27; P0.05. Moreover, meta-regression analysis found no relationship between the method used to assess ED (questionnaire or interview, mean age, mean hemoglobin A(1c, mean body mass index, or mean duration of diabetes and the risk of CV events or CHD. In the cross-sectional studies, the OR of diabetic men with ED versus those without ED was 3.39 (95% CI: 2.58-4.44; P<0.001 for CV events (N = 9, 3.43 (95% CI: 2.46-4.77; P<0.001 for CHD (N = 7, and 2.63 (95% CI: 1.41-4.91; P = 0.002 for peripheral vascular disease (N = 5. CONCLUSION/SIGNIFICANCE: ED was associated with an increased risk of CV events in diabetic patients. Prevention and early detection of cardiovascular disease are important in the management of diabetes, especially in view of the rapid increase in its prevalence.
Choueiri, Toni K.; Je, Youjin; Cho, Eunyoung
Analgesics are the most commonly used over-the-counter drugs worldwide with certain analgesics having cancer prevention effect. The evidence for an increased risk of developing kidney cancer with analgesic use is mixed. Using a meta-analysis design of available observational epidemiologic studies, we investigated the association between analgesic use and kidney cancer risk. We searched the MEDLINE and EMBASE databases to identify eligible case-control or cohort studies published in English until June 2012 for 3 categories of analgesics: acetaminophen, aspirin or other Non-Steroidal Anti-Inflammatory Drugs (NSAIDs). Study-specific effect estimates were pooled to compute an overall relative risk (RR) and its 95% confidence interval (CI) using a random effects model for each category of the analgesics. We identified 20 studies (14 with acetaminophen, 13 with aspirin, and 5 with other NSAIDs) that were performed in 6 countries, including 8,420 cases of kidney cancer. Use of acetaminophen and non-aspirin NSAIDs were associated with an increased risk of kidney cancer (pooled RR, 1.28; 95% CI, 1.15 to 1.44 and 1.25; 95% CI, 1.06 to 1.46, respectively). For aspirin use, we found no overall increased risk (pooled RR, 1.10; 95% CI, 0.95 to 1.28), except for non-US studies (5 studies, pooled RR=1.17, 95% CI, 1.04 to 1.33). Similar increases in risks were seen with higher analgesic intake. In this largest meta-analysis to date, we found that acetaminophen and non-aspirin NSAIDs are associated with a significant risk of developing kidney cancer. Further work is needed to elucidate biologic mechanisms behind these findings. PMID:23400756
Wiedermann, Christian J; Wiedermann, Wolfgang; Joannidis, Michael
To test the hypothesis that hypoalbuminemia is independently associated with increased risk of acute kidney injury (AKI). A meta-analysis was performed of observational clinical studies evaluating the relationship between serum albumin level and the occurrence of AKI by multivariate methods. Additionally, the impact was assessed of lower serum albumin on mortality in patients who developed AKI. Eligible studies were sought by multiple methods, and adjusted odds ratios (OR) were quantitatively combined using a random effects model. Seventeen clinical studies with 3,917 total patients were included: 11 studies (6 in surgical or intensive care unit patients and 5 in other hospital settings) evaluating the influence of serum albumin on AKI incidence and 6 studies describing the relationship between serum albumin and mortality among patients who had developed AKI. Lower serum albumin was an independent predictor both of AKI and of death after AKI development. With each 10 g L(-1) serum albumin decrement, the odds of AKI increased by 134%. The pooled OR for AKI was 2.34 with a 95% confidence interval (CI) of 1.74-3.14. Among patients who had developed AKI, the odds of death rose 147% (pooled OR 2.47, 95% CI 1.51-4.05) with each 10 g L(-1) serum albumin decrement. This meta-analysis provides evidence that hypoalbuminemia is a significant independent predictor both of AKI and of death following AKI development. Serum albumin determinations may be of utility in identifying patients at increased risk for AKI or for death after AKI. Controlled studies are warranted to assess interventions aimed at correcting hypoalbuminemia.
Rafiei, Mohammad; Kiani, Faezeh; Sayehmiri, Fatemeh; Sayehmiri, Kourosh; Sheikhi, Abdolkarim; Zamanian Azodi, Mona
Background : The mouth cavity hosts various types of anaerobic bacteria including Porphyromonas gingivalis , which causes periodontal inflammatory diseases. P. gingivalis is a gram-negative oral anaerobe and is considered as a main etiological factor in periodontal diseases. Several studies have reported a relationship between P. gingivalis in individuals with periodontal diseases and a critical role of this bacterium in the pathogenesis of periodontal diseases. The present study aimed at estimating this probability using a meta-analysis. Methods : We searched several databases including PubMed, Scopus, Google Scholar, and Web of Science to identify case-control studies addressing the relationship between P. gingivalis with periodontal diseases. A total of 49 reports published from different countries from 1993 to 2014 were included in this study. I² (heterogeneity index) statistics were calculated to examine heterogeneity. Data were analyzed using STATA Version 11. Results : After a detailed analysis of the selected articles, 49 case-control studies with 5924 individuals fulfilled the inclusion criteria for the meta-analysis. The healthy controls included 2600 healthy individuals with a Mean±SD age of 36.56±7.45 years. The periodontal diseases group included 3356 patients with a mean age of 43.62±8.35 years. There was a statistically significant difference between P. gingivalis in periodontal patients and healthy controls; 9.24 (95% CI: 5.78 to 14.77; P = 0.000). In the other word, there was a significant relationship between the presence of P. gingivalis and periodontal diseases. Conclusion : Analyzing the results of the present study, we found a strong association between the presence of P. gingivalis and periodontal diseases. This result suggests that another research is needed to further assess this subject.
Pappachan, Joseph M; Raskauskiene, Diana; Kutty, V Raman; Clayton, Richard N
Several previous observational studies showed an association between hypopituitarism and excess mortality. Reports on reduction of standard mortality ratio (SMR) with GH replacement have been published recently. This meta-analysis assessed studies reporting SMR to clarify mortality risk in hypopituitary adults and also the potential benefit conferred by GH replacement. A literature search was performed in Medline, Embase, and Cochrane library up to March 31, 2014. Studies with or without GH replacement reporting SMR with 95% confidence intervals (95% CI) were included. Patient characteristics, SMR data, and treatment outcomes were independently assessed by two authors, and with consensus from third author, studies were selected for analysis. Meta-analysis was performed in all studies together, and those without and with GH replacement separately, using the statistical package metafor in R. Six studies reporting a total of 19 153 hypopituiatary adults with a follow-up duration of more than 99,000 person years were analyzed. Hypopituitarism was associated with an overall excess mortality (weighted SMR, 1.99; 95% CI, 1.21-2.76) in adults. Female hypopituitary adults showed higher SMR compared with males (2.53 vs 1.71). Onset of hypopituitarism at a younger age was associated with higher SMR. GH replacement improved the mortality risk in hypopituitary adults that is comparable to the background population (SMR with GH replacement, 1.15; 95% CI, 1.05-1.24 vs SMR without GH, 2.40; 95% CI, 1.46-3.34). GH replacement conferred lower mortality benefit in hypopituitary women compared with men (SMR, 1.57; 95% CI, 1.38-1.77 vs 0.95; 95% CI, 0.85-1.06). There was a potential selection bias of benefit of GH replacement from a post-marketing data necessitating further evidence from long-term randomized controlled trials. Hypopituitarism may increase premature mortality in adults. Mortality benefit from GH replacement in hypopituitarism is less pronounced in women than men.
Meta-analysis is a statistical method to summarize research data from multiple studies in a quantitative manner. This dissertation addresses a number of methodological topics in causal meta-analysis and reports the development and validation of meta-analysis software. In the first (methodological)
Beales, Ian L P; Dearman, Leanne; Vardi, Inna; Loke, Yoon
Use of statins has been associated with a reduced incidence of esophageal adenocarcinoma in population-based studies. However there are few studies examining statin use and the development of Barrett's esophagus. The purpose of this study was to examine the association between statin use and the presence of Barrett's esophagus in patients having their first gastroscopy. We have performed a case-control study comparing statin use between patients with, and without, an incident diagnosis of non-dysplastic Barrett's esophagus. Male Barrett's cases (134) were compared to 268 male age-matched controls in each of two control groups (erosive gastro-esophageal reflux and dyspepsia without significant upper gastrointestinal disease). Risk factor and drug exposure were established using standardised interviews. Logistic regression was used to compare statin exposure and correct for confounding factors. We performed a meta-analysis pooling our results with three other case-control studies. Regular statin use was associated with a significantly lower incidence of Barrett's esophagus compared to the combined control groups [adjusted OR 0.62 (95 % confidence intervals 0.37-0.93)]. This effect was more marked in combined statin plus aspirin users [adjusted OR 0.43 (95 % CI 0.21-0.89)]. The inverse association between statin or statin plus aspirin use and risk of Barrett's was significantly greater with longer duration of use. Meta-analysis of pooled data (1098 Barrett's, 2085 controls) showed that statin use was significantly associated with a reduced risk of Barrett's esophagus [pooled adjusted OR 0.63 (95 % CI 0.51-0.77)]. Statin use is associated with a reduced incidence of a new diagnosis of Barrett's esophagus.
Navickis, Roberta J; Greenhalgh, David G; Wilkes, Mahlon M
Critical appraisal of outcomes after burn shock resuscitation with albumin has previously been restricted to small relatively old randomized trials, some with high risk of bias. Extensive recent data from nonrandomized studies assessing the use of albumin can potentially reduce bias and add precision. The objective of this meta-analysis was to determine the effect of burn shock resuscitation with albumin on mortality and morbidity in adult patients. Randomized and nonrandomized controlled clinical studies evaluating mortality and morbidity in adult patients receiving albumin for burn shock resuscitation were identified by multiple methods, including computer database searches and examination of journal contents and reference lists. Extracted data were quantitatively combined by random-effects meta-analysis. Four randomized and four nonrandomized studies with 688 total adult patients were included. Treatment effects did not differ significantly between the included randomized and nonrandomized studies. Albumin infusion during the first 24 hours showed no significant overall effect on mortality. However, significant statistical heterogeneity was present, which could be abolished by excluding two studies at high risk of bias. After those exclusions, albumin infusion was associated with reduced mortality. The pooled odds ratio was 0.34 with a 95% confidence interval of 0.19 to 0.58 (P Albumin administration was also accompanied by decreased occurrence of compartment syndrome (pooled odds ratio, 0.19; 95% confidence interval, 0.07-0.50; P albumin can improve outcomes of burn shock resuscitation. However, the scope and quality of current evidence are limited, and additional trials are needed.
Ng, MYM; Levinson, DF; Faraone, SV; Suarez, BK; DeLisi, LE; Arinami, T; Riley, B; Paunio, T; Pulver, AE; Irmansyah; Holmans, PA; Escamilla, M; Wildenauer, DB; Williams, NM; Laurent, C; Mowry, BJ; Brzustowicz, LM; Maziade, M; Sklar, P; Garver, DL; Abecasis, GR; Lerer, B; Fallin, MD; Gurling, HMD; Gejman, PV; Lindholm, E; Moises, HW; Byerley, W; Wijsman, EM; Forabosco, P; Tsuang, MT; Hwu, H-G; Okazaki, Y; Kendler, KS; Wormley, B; Fanous, A; Walsh, D; O’Neill, FA; Peltonen, L; Nestadt, G; Lasseter, VK; Liang, KY; Papadimitriou, GM; Dikeos, DG; Schwab, SG; Owen, MJ; O’Donovan, MC; Norton, N; Hare, E; Raventos, H; Nicolini, H; Albus, M; Maier, W; Nimgaonkar, VL; Terenius, L; Mallet, J; Jay, M; Godard, S; Nertney, D; Alexander, M; Crowe, RR; Silverman, JM; Bassett, AS; Roy, M-A; Mérette, C; Pato, CN; Pato, MT; Roos, J Louw; Kohn, Y; Amann-Zalcenstein, D; Kalsi, G; McQuillin, A; Curtis, D; Brynjolfson, J; Sigmundsson, T; Petursson, H; Sanders, AR; Duan, J; Jazin, E; Myles-Worsley, M; Karayiorgou, M; Lewis, CM
A genome scan meta-analysis (GSMA) was carried out on 32 independent genome-wide linkage scan analyses that included 3255 pedigrees with 7413 genotyped cases affected with schizophrenia (SCZ) or related disorders. The primary GSMA divided the autosomes into 120 bins, rank-ordered the bins within each study according to the most positive linkage result in each bin, summed these ranks (weighted for study size) for each bin across studies and determined the empirical probability of a given summed rank (PSR) by simulation. Suggestive evidence for linkage was observed in two single bins, on chromosomes 5q (142-168 Mb) and 2q (103-134 Mb). Genome-wide evidence for linkage was detected on chromosome 2q (119-152 Mb) when bin boundaries were shifted to the middle of the previous bins. The primary analysis met empirical criteria for ‘aggregate’ genome-wide significance, indicating that some or all of 10 bins are likely to contain loci linked to SCZ, including regions of chromosomes 1, 2q, 3q, 4q, 5q, 8p and 10q. In a secondary analysis of 22 studies of European-ancestry samples, suggestive evidence for linkage was observed on chromosome 8p (16-33 Mb). Although the newer genome-wide association methodology has greater power to detect weak associations to single common DNA sequence variants, linkage analysis can detect diverse genetic effects that segregate in families, including multiple rare variants within one locus or several weakly associated loci in the same region. Therefore, the regions supported by this meta-analysis deserve close attention in future studies. PMID:19349958
The purpose of this study was to examine the effects of conflict resolution, peace education and peer mediation on the conflict resolution skills of students via meta-analysis method. 23 studies were determined to be in accordance with the study criteria. According to research findings conflict resolution, peace education and peer mediation…
Conclusion: This is the first meta-analysis of the relationship of total dairy intake with CVD. This study showed an inverse relationship between total dairy intake and CVD while no relationship was found for CHD. Considering the limited number of studies in this regard, more studies are required to investigate the effect of different factors on the association of dairy intake and CVD.
Çogaltay, Nazim; Karadag, Engin
The purpose of this study is to test the effect of educational leadership on some organizational variables using meta-analysis method. In this context, the results of independent researches were merged together and the hypotheses created within the scope of the study were tested. In order to determine the researches to be included in the study,…
Huang, Zhicong; Lin, Huang; Fellay, Jacques; Kutalik, Zoltán; Hubaux, Jean-Pierre
Due to the limited power of small-scale genome-wide association studies (GWAS), researchers tend to collaborate and establish a larger consortium in order to perform large-scale GWAS. Genome-wide association meta-analysis (GWAMA) is a statistical tool that aims to synthesize results from multiple independent studies to increase the statistical power and reduce false-positive findings of GWAS. However, it has been demonstrated that the aggregate data of individual studies are subject to inference attacks, hence privacy concerns arise when researchers share study data in GWAMA. In this article, we propose a secure quality control (SQC) protocol, which enables checking the quality of data in a privacy-preserving way without revealing sensitive information to a potential adversary. SQC employs state-of-the-art cryptographic and statistical techniques for privacy protection. We implement the solution in a meta-analysis pipeline with real data to demonstrate the efficiency and scalability on commodity machines. The distributed execution of SQC on a cluster of 128 cores for one million genetic variants takes less than one hour, which is a modest cost considering the 10-month time span usually observed for the completion of the QC procedure that includes timing of logistics. SQC is implemented in Java and is publicly available at https://github.com/acs6610987/secureqc. email@example.com. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: firstname.lastname@example.org
Full Text Available Introduction: The mean age of menopause have been reported at the age of 51 in the world and regarding the increase in life expectancy in many countries more than a third of the life time of women i s in menopause period. The importance of menopause is due to its relationship with various diseases and quality of life. The present study was conducted to estimate the average natural age of menopause in women based on a meta-analysis study. Material and Methods: In a meta-analysis study on all the existing articles in the natural age o f menopause in Iran, 21 articles were selected based on inclusion criteria. Begg and Egger tests fo r publication bias and Cochrane test were used to determine the heterogeneity among samples. ???? estimate of mean calculated based on Random effect model in Stata11 software. Results: The publication bias assumption was rejected by Begg and Egger tests with significant value s equal to 0.174 and 0.446 respectively. There was a heterogeneity among samples (Q=4626.3, df=20 , P<0.001. So based on random effect model the mean age of menopause was calculated as 48.183 with 95 % CI=47.457-48.91. Conclusion: The average age of natural menopause in Iranian women is favorable to some places of Middle East, but is less compared with developed countries and the world mean. Because of the importance of this period in women, educational programs seem to be necessary.
Schäfer, Mike S
The presentation of science in the mass media is one of the most important questions facing social scientists who analyse science. Accordingly, media coverage of science has been a constant focal point in the respective literature, and a flurry of such publications has appeared in the past few years. Yet the activity and growth of the respective research have not been accompanied by systematic overviews. This article aims to provide such an overview by means of a meta-analysis: it analyses existing studies systematically and provides an empirical overview of the literature. The analysis shows that while the research field grew significantly in the past few years and employs a variety of research strategies and methods, it has been biased in three ways: mainly natural sciences (and namely biosciences and medicine), Western countries, and print media have been analysed.
da Silva, Felipe Rodolfo Pereira; Vasconcelos, Any Carolina Cardoso Guimarães; de Carvalho França, Luiz Felipe; Di Lenardo, David; Nascimento, Hélio Mateus Silva; Vasconcelos, Daniel Fernando Pereira
Several factors are involved in the periodontitis with host response through cytokines and as well as with influence of polymorphisms in cytokine genes, however the results remained contradictory. This study aimed at evaluating the rs1143634 polymorphism in interleukin-1B gene, a cytokine gene, and the risk of chronic periodontitis with conducting a meta-analysis focusing in ethnicity. A review in literature was performed in several databases to studies published before June 2017. Data extraction was performed by two calibrated investigators and the calculations of the meta-analysis were obtained through Review Manager version 5.2 statistical software with Odds Ratio (OR) calculation and Funnel plot (P 0.05). No publication bias was found in allelic evaluation. This meta-analysis in 9376 participants with 54 case/control studies revealed the rs1143634 polymorphism was associated with elevated risk of chronic periodontitis in overall analysis as well as Caucasian and Asian ethnicities and Mixed population. Copyright © 2018 Elsevier B.V. All rights reserved.
Donga, Esther; Dekkers, Olaf M.; Corssmit, Eleonora P. M.; Romijn, Johannes A.
Objective: The aim of this study was to perform a systematic review and meta-analysis on insulin resistance in adult patients with type 1 diabetes mellitus compared to healthy controls, assessed by hyperinsulinemic euglycemic clamp studies. Design and methods: We conducted a systematic search of
Singer, George H. S.
Meta-analysis was used to synthesize findings from comparative studies of depression in mothers of children with and without developmental disabilities. Effect sizes were determined for 18 studies conducted between 1984 and 2003. A weighted effect size of 0.39 indicated an elevated level of depression in mothers of children with developmental…
Shyamani Siriwardena; Kevin Boyle; Tom Holmes; P. Eric Wiseman
Trees in residential neighborhoods and communities provide benefits for homeowners that are capitalized intoÂ residential property values. In this paper, we collected data from hedonic property value studies and mergedÂ these data with ancillary spatial data describing forest and socio-economic characteristics surrounding eachÂ study area to conduct a meta-analysis of the...
Yan, Dandan; Zhao, Enfa; Zhang, Hong; Luo, Xiaohui; Du, Yajuan
A potential association between type 1 diabetes mellitus and subsequent epilepsy emerged in recent studies. This study aimed to evaluate the possible relationship between type 1 diabetes mellitus and epilepsy using meta-analysis. Pubmed, ISI Web of Knowledge, Embase and Cochrane Library were searched for potential studies of the association between type 1 diabetes mellitus and epilepsy from inception to February 1, 2017. Two investigators independently screened studies for inclusion and extracted related data; discrepancies were solved by consensus. Random effects model of Hazard Ratio (HR) was used to estimate the strength of association. We identified 13 papers from potentially relevant articles of which 3 cohort studies met the inclusion criteria. Random effects meta-analysis showed that type 1 diabetes mellitus was associated with an increased risk of epilepsy with HR = 3.29 (95% CI: 2.61-4.14; I 2 = 0, p = 0.689). Similar results were observed in type 1 diabetes mellitus patents younger than 18-years-old with HR = 2.96 (95% CI: 2.28-3.84; I 2 = 0, p = 0.571). Meta-analysis of 2 studies that adjusted for potential confounders yielded an increased risk of epilepsy with HR = 2.89 (95% CI: 2.26-3.70; I 2 = 0, p = 0.831). The meta-analysis indicates that type 1 diabetes mellitus is associated with a statistically significant increased risk for epilepsy compared to those without type 1 diabetes mellitus.
Sangnawakij, Patarawan; Böhning, Dankmar; Adams, Stephen; Stanton, Michael; Holling, Heinz
Statistical inference for analyzing the results from several independent studies on the same quantity of interest has been investigated frequently in recent decades. Typically, any meta-analytic inference requires that the quantity of interest is available from each study together with an estimate of its variability. The current work is motivated by a meta-analysis on comparing two treatments (thoracoscopic and open) of congenital lung malformations in young children. Quantities of interest include continuous end-points such as length of operation or number of chest tube days. As studies only report mean values (and no standard errors or confidence intervals), the question arises how meta-analytic inference can be developed. We suggest two methods to estimate study-specific variances in such a meta-analysis, where only sample means and sample sizes are available in the treatment arms. A general likelihood ratio test is derived for testing equality of variances in two groups. By means of simulation studies, the bias and estimated standard error of the overall mean difference from both methodologies are evaluated and compared with two existing approaches: complete study analysis only and partial variance information. The performance of the test is evaluated in terms of type I error. Additionally, we illustrate these methods in the meta-analysis on comparing thoracoscopic and open surgery for congenital lung malformations and in a meta-analysis on the change in renal function after kidney donation. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Alfotih, Gobran Taha Ahmed; Li, FangCheng; Xu, XinKe; Zhang, ShangYi
The mortality of re-bleeding following aneurysmal subarachnoid hemorrhage is high, and surviving patients often have poor clinical condition and worse outcome than patients with a single bleed. In this study, we performed an updated systematic review and meta-analysis to determine the most common risk factors for re-bleeding in this patient population, with the goal of providing neurologists, neurosurgeons, neuro-interventionalists with a simple and fast method to evaluate the re-bleeding risk for aneurysmal subarachnoid hemorrhage. We conducted a thorough meta-analysis of the risk factors associated with re-bleeding or re-rupture of intracranial aneurysms in cases published between 2000 and 2013. Pooled mean difference was calculated for the continuous variables (age), and pooled odds ratio (OR) was calculated for categorical factors. If heterogeneity was significant (pbleeding, resulting in a weighted average rate of re-bleeding of 11.3% with 95% confidence interval [CI]: 10.1-12.6. In this population, sex (OR 1.46; 95% CI: 1.11-1.92), high systolic blood pressure [SBP] (OR 2.52; 95% CI: 1.40-4.53), aneurysm size (OR 3.00; 95% CI: 2.06-4.37), clinical condition (Hunt & Hess) (OR 4.94; 95% CI: 2.29,10.68), and Fisher grade (OR 2.29; 95% CI: 1.45, 3.61) were statistically significant risk factors for re-bleeding. Sex, high SBP, high Fisher grade, aneurysm size larger than 10mm, and poor clinical condition were independent risk factors for aneurysmal re-bleeding. The importance of early aneurysm intervention and careful consideration of patient risk factors should be emphasized to eliminate the risk of re-bleeding and poor outcome. Copyright © 2014 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.
Wang, Zhaoming; McGlynn, Katherine A.; Rajpert-De Meyts, Ewa
The international Testicular Cancer Consortium (TECAC) combined five published genome-wide association studies of testicular germ cell tumor (TGCT; 3,558 cases and 13,970 controls) to identify new susceptibility loci. We conducted a fixed-effects meta-analysis, including, to our knowledge, the fi...
Gijsbers, L.; Ding, E.L.; Malik, Vasanti; Goede, de J.; Geleijnse, J.M.; Soedamah-Muthu, S.S.
BACKGROUND: A growing number of cohort studies suggest a potential role of dairy consumption in type 2 diabetes (T2D) prevention. The strength of this association and the amount of dairy needed is not clear. OBJECTIVE: We performed a meta-analysis to quantify the associations of incident T2D with
Pasipanodya, Jotam G.; Srivastava, Shashikant; Gumbo, Tawanda
Laboratory studies have questioned nonadherence as a cause of antituberculosis drug failure and propose that between-patient pharmacokinetic variability may be the cause. This meta-analysis provides clinical evidence that pharmacokinetic variability of isoniazid alone leads to worse microbiological failure, relapse, and acquired drug resistance.
Morina, N.; Ijntema, H.; Meyerbröker, K.; Emmelkamp, P.M.G.
In virtual reality exposure therapy (VRET), patients are exposed to virtual environments that resemble feared real-life situations. The aim of the current study was to assess the extent to which VRET gains can be observed in real-life situations. We conducted a meta-analysis of clinical trials
This meta-analysis summarizes the influence of Turkish teacher's gender and marital status on their perception of organizational commitment. In total, 30 independent research studies conducted across the country are investigated to analyze the relations between gender and organizational commitment, i.e., a sample group of 11,724 participants. In…
Foody, Mairéad; Samara, Muthanna; O'Higgins Norman, James
Background: Bullying research has gained a substantial amount of interest in recent years because of the implications for child and adolescent development. Aim and sample: We conducted a meta-analysis of traditional and cyberbullying studies in the Republic and North of Ireland to gain an understanding of prevalence rates and associated issues…
Aune, D.; Chan, D.S.M.; Vieira, A.; Navarro Rosenblatt, D.; Vieira, R.; Greenwood, D.C.; Kampman, E.; Norat, T.
Background Current evidence indicates that red and processed meat intake increases the risk of colorectal cancer; however, the association with colorectal adenomas is unclear. Objective To conduct a systematic review and meta-analysis of epidemiological studies of red and processed meat intake and
Springelkamp, Henriët; Höhn, René; Mishra, Aniket; Hysi, Pirro G; Khor, Chiea-Chuen; Loomis, Stephanie J; Bailey, Jessica N Cooke; Gibson, Jane; Thorleifsson, Gudmar; Janssen, Sarah F; Luo, Xiaoyan; Ramdas, Wishal D; Vithana, Eranga; Nongpiur, Monisha E; Montgomery, Grant W; Xu, Liang; Mountain, Jenny E; Gharahkhani, Puya; Lu, Yi; Amin, Najaf; Karssen, Lennart C; Sim, Kar-Seng; van Leeuwen, Elisabeth M; Iglesias, Adriana I; Verhoeven, Virginie J M; Hauser, Michael A; Loon, Seng-Chee; Despriet, Dominiek D G; Nag, Abhishek; Venturini, Cristina; Sanfilippo, Paul G; Schillert, Arne; Kang, Jae H; Landers, John; Jonasson, Fridbert; Cree, Angela J; van Koolwijk, Leonieke M E; Rivadeneira, Fernando; Souzeau, Emmanuelle; Jonsson, Vesteinn; Menon, Geeta; Weinreb, Robert N; de Jong, Paulus T V M; Oostra, Ben A; Uitterlinden, André G; Hofman, Albert; Ennis, Sarah; Thorsteinsdottir, Unnur; Burdon, Kathryn P; Spector, Timothy D; Mirshahi, Alireza; Saw, Seang-Mei; Vingerling, Johannes R; Teo, Yik-Ying; Haines, Jonathan L; Wolfs, Roger C W; Lemij, Hans G; Tai, E-Shyong; Jansonius, Nomdo M; Jonas, Jost B; Cheng, Ching-Yu; Aung, Tin; Viswanathan, Ananth C; Klaver, Caroline C W; Craig, Jamie E; Macgregor, Stuart; Mackey, David A; Lotery, Andrew J; Stefansson, Kari; Bergen, Arthur A B; Young, Terri L; Wiggs, Janey L; Pfeiffer, Norbert; Wong, Tien-Yin; Pasquale, Louis R; Hewitt, Alex W; van Duijn, Cornelia M; Hammond, Christopher J
Glaucoma is characterized by irreversible optic nerve degeneration and is the most frequent cause of irreversible blindness worldwide. Here, the International Glaucoma Genetics Consortium conducts a meta-analysis of genome-wide association studies of vertical cup-disc ratio (VCDR), an important
Grabe, Shelly; Ward, L. Monique; Hyde, Janet Shibley
Research suggests that exposure to mass media depicting the thin-ideal body may be linked to body image disturbance in women. This meta-analysis examined experimental and correlational studies testing the links between media exposure to women's body dissatisfaction, internalization of the thin ideal, and eating behaviors and beliefs with a sample…
Full Text Available BACKGROUND: The association between cytotoxic T-lymphocyte antigen 4 (CTLA-4 gene -1722T/C polymorphism (rs733618 and cancer has been widely assessed, and a definitive conclusion remains elusive. We first performed a hospital based case-control study to measure this association of esophageal cancer with CTLA-4 -1722T/C polymorphism in Han Chinese population, and then carried out a meta-analysis to obtain a comprehensive evaluation for this issue. METHODOLOGY/PRINCIPAL FINDINGS: This case-control study involved 629 esophageal squamous cell carcinoma (ESCC cases and 686 age and gender well matched cancer-free controls. PCR-LDR (polymerase chain reaction-ligase detection reactions method was used to identify genotypes. Meta-analysis was conducted by STATA (v12.0 software. This case-control study showed no significant difference in the genotype and allele distributions of CTLA-4 -1722T/C polymorphism between esophageal cancer cases and control subjects, in accord with the findings of the further meta-analysis in all genetic models. Evidence of large heterogeneity was observed among all eligible studies in the recessive model. Further subgroup analyses by ethnicity, cancer type and system, detected null associations in this meta-analysis. CONCLUSION: This case-control study and the further meta-analysis, failed to identify the association between CTLA-4 -1722T/C polymorphism and cancer risk.
Svahn, Malene F; Faber, Mette Tuxen; Christensen, Jane
The role of human papillomavirus (HPV) in the pathogenesis of ovarian cancer is controversial, and conflicting results have been published. We conducted a systematic review and meta-analysis to estimate the prevalence of HPV in epithelial ovarian cancer tissue....
Li, Lian; Zhang, Shuang; Huang, Yubei; Chen, Kexin
Childhood obesity is a major public problem worldwide, and sleep duration may be associated with childhood obesity. We conducted a systematic review and meta-analysis of prospective cohort studies to estimate the associations between sleep duration and obesity/body mass index (BMI) in children. PubMed, Embase and the Cochrane Library were searched. For the meta-analysis, the pooled relative risk (RR) and 95% confidence intervals (CI) were estimated to reveal the association between short sleep duration and obesity. For the review, the outcomes focused on BMI change or subsequent BMI status. A total of 12 studies (15 populations) met the criteria for inclusion in the meta-analysis. Short sleep duration was significantly associated with obesity (RR: 1.45; 95% CI: 1.14-1.85). After excluding two cohorts that substantially affected the heterogeneity, the pooled results remained significant (RR: 1.30; 95% CI: 1.20-1.42), and the association was not substantially altered in the subgroup analysis. In addition, we summarised 24 studies that met the criteria for our review of the relationship between sleeping and BMI. The present meta-analysis indicated that short sleep duration increased the risk of childhood obesity. Public health efforts that encourage children to have sufficient sleep time may be important in combating obesity. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).
Yang, Jingjing; Chen, Sai; Abecasis, Gonçalo
Meta-analysis is now an essential tool for genetic association studies, allowing them to combine large studies and greatly accelerating the pace of genetic discovery. Although the standard meta-analysis methods perform equivalently as the more cumbersome joint analysis under ideal settings, they result in substantial power loss under unbalanced settings with various case-control ratios. Here, we investigate the power loss problem by the standard meta-analysis methods for unbalanced studies, and further propose novel meta-analysis methods performing equivalently to the joint analysis under both balanced and unbalanced settings. We derive improved meta-score-statistics that can accurately approximate the joint-score-statistics with combined individual-level data, for both linear and logistic regression models, with and without covariates. In addition, we propose a novel approach to adjust for population stratification by correcting for known population structures through minor allele frequencies. In the simulated gene-level association studies under unbalanced settings, our method recovered up to 85% power loss caused by the standard methods. We further showed the power gain of our methods in gene-level tests with 26 unbalanced studies of age-related macular degeneration . In addition, we took the meta-analysis of three unbalanced studies of type 2 diabetes as an example to discuss the challenges of meta-analyzing multi-ethnic samples. In summary, our improved meta-score-statistics with corrections for population stratification can be used to construct both single-variant and gene-level association studies, providing a useful framework for ensuring well-powered, convenient, cross-study analyses. © 2018 WILEY PERIODICALS, INC.
Wang, Wei; Liu, Lei; Wang, Zhiwei; Lu, Xiaopeng; Wei, Min; Lin, Tianlong; Zhang, Yixin; Jiang, Songqi; Wang, Qiang; Cao, Ziang; Shi, Minxin
The association between ABO blood group and the risk of esophageal carcinoma (EC) in previously published studies is uncertain and conflicting. The aim of the current study was to determine the correlation of ABO blood group with EC risk via a case-control study and meta-analysis. We performed a population-based case-control study of 3,595 cases and 41,788 controls in Chinese population to evaluate the association between ABO blood group and EC risk. Then, a comprehensive meta-analysis combining our original data and previously published data was conducted to clearly discern the real relationship. The strength of association was measured by odds ratios (ORs) with 95% confidence intervals (CI). In our case-control study, the risk of EC in blood group B was significantly higher than that in non-B groups (A, O, and AB) (OR = 1.15, 95% CI 1.09-1.21). Compared with non-O groups (A, B, and AB), individuals with blood group O demonstrated a reduced risk of EC (OR = 0.90, 95% CI 0.85-0.94). The meta-analysis also indicated that blood group B was associated with significantly higher EC risk (OR = 1.20, 95% CI 1.10-1.31), and people with blood group O had a decreased EC risk (OR = 0.94, 95% CI 0.90-0.99). Neither the case-control study nor the meta-analysis produced any significant association of blood group A or AB with EC risk. Results from our case-control study and the followed meta-analysis confirmed that there was an increased risk of EC in blood group B individuals, whereas a decreased risk of EC was observed in blood group O individuals.
Cook, James P; Mahajan, Anubha; Morris, Andrew P
Linear mixed models are increasingly used for the analysis of genome-wide association studies (GWAS) of binary phenotypes because they can efficiently and robustly account for population stratification and relatedness through inclusion of random effects for a genetic relationship matrix. However, the utility of linear (mixed) models in the context of meta-analysis of GWAS of binary phenotypes has not been previously explored. In this investigation, we present simulations to compare the performance of linear and logistic regression models under alternative weighting schemes in a fixed-effects meta-analysis framework, considering designs that incorporate variable case-control imbalance, confounding factors and population stratification. Our results demonstrate that linear models can be used for meta-analysis of GWAS of binary phenotypes, without loss of power, even in the presence of extreme case-control imbalance, provided that one of the following schemes is used: (i) effective sample size weighting of Z-scores or (ii) inverse-variance weighting of allelic effect sizes after conversion onto the log-odds scale. Our conclusions thus provide essential recommendations for the development of robust protocols for meta-analysis of binary phenotypes with linear models.
Du, Shu-Li; Geng, Ting-Ting; Feng, Tian; Chen, Cui-Ping; Jin, Tian-Bo; Chen, Chao
The association between the RTEL1 rs6010620 single nucleotide polymorphism (SNP) and glioma risk has been extensively studied. However, the results remain inconclusive. To further examine this association, we performed a meta-analysis. A computerized search of the PubMed and Embase databases for publications regarding the RTEL1 rs6010620 polymorphism and glioma cancer risk was performed. Genotype data were analyzed in a meta-analysis. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association. Sensitivity analyses, tests of heterogeneity, cumulative meta-analyses, and assessments of bias were performed in our meta-analysis. Our meta-analysis confirmed that risk with allele A is lower than with allele G for glioma. The A allele of rs6010620 in RTEL1 decreased the risk of developing glioma in the 12 case-control studies for all genetic models: the allele model (OR=0.752, 95%CI: 0.715-0.792), the dominant model (OR=0.729, 95%CI: 0.685-0.776), the recessive model (OR=0.647, 95%CI: 0.569-0.734), the homozygote comparison (OR=0.528, 95%CI: 0.456-0.612), and the heterozygote comparison (OR=0.761, 95%CI: 0.713-0.812). In all genetic models, the association between the RTEL1 rs6010620 polymorphism and glioma risk was significant. This meta-analysis suggests that the RTEL1 rs6010620 polymorphism may be a risk factor for glioma. Further functional studies evaluating this polymorphism and glioma risk are warranted.
La Gamba, Fabiola; Corrao, Giovanni; Romio, Silvana; Sturkenboom, Miriam; Trifirò, Gianluca; Schink, Tania; de Ridder, Maria
Clustering of patients in databases is usually ignored in one-stage meta-analysis of multi-database studies using matched case-control data. The aim of this study was to compare bias and efficiency of such a one-stage meta-analysis with a two-stage meta-analysis. First, we compared the approaches by generating matched case-control data under 5 simulated scenarios, built by varying: (1) the exposure-outcome association; (2) its variability among databases; (3) the confounding strength of one covariate on this association; (4) its variability; and (5) the (heterogeneous) confounding strength of two covariates. Second, we made the same comparison using empirical data from the ARITMO project, a multiple database study investigating the risk of ventricular arrhythmia following the use of medications with arrhythmogenic potential. In our study, we specifically investigated the effect of current use of promethazine. Bias increased for one-stage meta-analysis with increasing (1) between-database variance of exposure effect and (2) heterogeneous confounding generated by two covariates. The efficiency of one-stage meta-analysis was slightly lower than that of two-stage meta-analysis for the majority of investigated scenarios. Based on ARITMO data, there were no evident differences between one-stage (OR = 1.50, CI = [1.08; 2.08]) and two-stage (OR = 1.55, CI = [1.12; 2.16]) approaches. When the effect of interest is heterogeneous, a one-stage meta-analysis ignoring clustering gives biased estimates. Two-stage meta-analysis generates estimates at least as accurate and precise as one-stage meta-analysis. However, in a study using small databases and rare exposures and/or outcomes, a correct one-stage meta-analysis becomes essential. Copyright © 2017 John Wiley & Sons, Ltd.
Chowdhury, Mohammad Ziaul Islam; Anik, Ataul Mustufa; Farhana, Zaki; Bristi, Piali Dey; Abu Al Mamun, B M; Uddin, Mohammad Jasim; Fatema, Jain; Akter, Tanjila; Tani, Tania Akhter; Rahman, Meshbahur; Turin, Tanvir C
Metabolic syndrome (MS) is a cluster of health problems that set the stage for serious health conditions and places individuals at higher risk of cardiovascular disease, diabetes and stroke. The worldwide prevalence of MS in the adult population is on the rise and Bangladesh is no exception. According to some epidemiological study, MS is highly prevalent in Bangladesh and has increased dramatically in last few decades. To provide a clear picture of the current situation, we conducted a systematic review and meta-analysis with an objective to assess the prevalence of metabolic syndrome among the Bangladeshi population using data already published in the scientific literature. We searched MEDLINE, EMBASE and PubMed and manually checked references of all identified relevant publications that described the prevalence of MS in Bangladesh. Random effects meta-analysis was used to pool the prevalence. Heterogeneity was explored using formal tests and subgroup analyses. Study quality and publication bias was also explored. Electronic and grey literature search retrieved 491 potentially relevant papers. After removing duplicates, reviewing titles and abstracts and screening full texts, 10 studies were finally selected. Most of the studies were conducted in rural populations and study participants were mostly females. The weighted pooled prevalence of metabolic syndrome regardless of gender and criteria used to define metabolic syndrome, was 30.0% with high heterogeneity observed. Weighted pooled prevalence of metabolic syndrome is higher in females (32%) compared to males (25%) though not statistically significant (p = 0.434). Prevalence was highest (37%) when Modified NCEP ATP III criteria was used to define MS, while it was lowest (20%) when WHO criteria was used. In most cases, geographical area (urban/rural) was identified as a source of heterogeneity between the studies. Most of the studies met study quality assessment criteria's except adequate sample size
Boeckle, Markus; Liegl, Gregor; Jank, Robert; Pieh, Christoph
Conversion Disorders (CD) are prevalent functional disorders. Although the pathogenesis is still not completely understood, an interaction of genetic, neurobiological, and psychosocial factors is quite likely. The aim of this study is to provide a systematic overview on imaging studies on CDs and investigate neuronal areas involved in Motor Conversion Disorders (MCD). A systematic literature search was conducted on CD. Subsequently a meta-analysis of functional neuroimaging studies on MCD was implemented using an Activation Likelihood Estimation (ALE). We calculated differences between patients and healthy controls as well as between affected versus unaffected sides in addition to an overall analysis in order to identify neuronal areas related to MCD. Patients with MCD differ from healthy controls in the amygdala, superior temporal lobe, retrosplenial area, primary motor cortex, insula, red nucleus, thalamus, anterior as well as dorsolateral prefrontal and frontal cortex. When comparing affected versus unaffected sides, temporal cortex, dorsal anterior cingulate cortex, supramarginal gyrus, dorsal temporal lobe, anterior insula, primary somatosensory cortex, superior frontal gyrus and anterior prefrontal as well as frontal cortex show significant differences. Neuronal areas seem to be involved in the pathogenesis, maintenance or as a result of MCD. Areas that are important for motor-planning, motor-selection or autonomic response seem to be especially relevant. Our results support the emotional unawareness theory but also underline the need of more support by conduction imaging studies on both CD and MCD.
Stevens, Jennifer S; Hamann, Stephan
Substantial sex differences in emotional responses and perception have been reported in previous psychological and psychophysiological studies. For example, women have been found to respond more strongly to negative emotional stimuli, a sex difference that has been linked to an increased risk of depression and anxiety disorders. The extent to which such sex differences are reflected in corresponding differences in regional brain activation remains a largely unresolved issue, however, in part because relatively few neuroimaging studies have addressed this issue. Here, by conducting a quantitative meta-analysis of neuroimaging studies, we were able to substantially increase statistical power to detect sex differences relative to prior studies, by combining emotion studies which explicitly examined sex differences with the much larger number of studies that examined only women or men. We used an activation likelihood estimation approach to characterize sex differences in the likelihood of regional brain activation elicited by emotional stimuli relative to non-emotional stimuli. We examined sex differences separately for negative and positive emotions, in addition to examining all emotions combined. Sex differences varied markedly between negative and positive emotion studies. The majority of sex differences favoring women were observed for negative emotion, whereas the majority of the sex differences favoring men were observed for positive emotion. This valence-specificity was particularly evident for the amygdala. For negative emotion, women exhibited greater activation than men in the left amygdala, as well as in other regions including the left thalamus, hypothalamus, mammillary bodies, left caudate, and medial prefrontal cortex. In contrast, for positive emotion, men exhibited greater activation than women in the left amygdala, as well as greater activation in other regions including the bilateral inferior frontal gyrus and right fusiform gyrus. These meta-analysis
Warlé, Michiel C.; Hooijmans, Carlijn R.
Both preclinical and clinical studies indicate that raised intra-abdominal pressure (IAP) associated with pneumoperitoneum during laparoscopic surgical procedures can cause renal damage, the severity of which may be influenced by variables such as pressure level and duration. Several of these variables have been investigated in animal studies, but synthesis of all preclinical data has not been performed. This systematic review summarizes all available pre-clinical evidence on this topic, including an assessment of its quality and risk of bias. We performed meta-analysis to assess which aspects of the pneumoperitoneum determine the severity of its adverse effects. A systematic search in two databases identified 55 studies on the effect of pneumoperitoneum on renal function which met our inclusion criteria. There was high heterogeneity between the studies regarding study design, species, sex, pressure and duration of pneumoperitoneum, and type of gas used. Measures to reduce bias were poorly reported, leading to an unclear risk of bias in the majority of studies. Details on randomisation, blinding and a sample size calculation were not reported in ≥80% of the studies. Meta-analysis showed an overall increase in serum creatinine during pneumoperitoneum, and a decrease in urine output and renal blood flow. Subgroup analysis indicated that for serum creatinine, this effect differed between species. Subgroup analysis of pressure level indicated that urine output decreased as IAP level increased. No differences between types of gas were observed. Data were insufficient to reliably assess whether sex or IAP duration modulate the effect of pneumoperitoneum. Four studies assessing long-term effects indicated that serum creatinine normalized ≥24 hours after desufflation of pneumoperitoneum at 15mmHg. We conclude that harmful effects on renal function and perfusion during pneumoperitoneum appear to be robust, but evidence on long-term effects is very limited. The
Yu, Kevin K; Cheung, Charlton; Chua, Siew E; McAlonan, Gráinne M
The question of whether Asperger syndrome can be distinguished from autism has attracted much debate and may even incur delay in diagnosis and intervention. Accordingly, there has been a proposal for Asperger syndrome to be subsumed under autism in the forthcoming Diagnostic and Statistical Manual of Mental Disorders, fifth edition, in 2013. One approach to resolve this question has been to adopt the criterion of absence of clinically significant language or cognitive delay--essentially, the "absence of language delay." To our knowledge, this is the first meta-analysis of magnetic resonance imaging (MRI) studies of people with autism to compare absence with presence of language delay. It capitalizes on the voxel-based morphometry (VBM) approach to systematically explore the whole brain for anatomic correlates of delay and no delay in language acquisition in people with autism spectrum disorders. We conducted a systematic search for VBM MRI studies of grey matter volume in people with autism. Studies with a majority (at least 70%) of participants with autism diagnoses and a history of language delay were assigned to the autism group (n = 151, control n = 190). Those with a majority (at least 70%) of individuals with autism diagnoses and no language delay were assigned to the Asperger syndrome group (n = 149, control n = 214). We entered study coordinates into anatomic likelihood estimation meta-analysis software with sampling size weighting to compare grey matter summary maps driven by Asperger syndrome or autism. The summary autism grey matter map showed lower volumes in the cerebellum, right uncus, dorsal hippocampus and middle temporal gyrus compared with controls; grey matter volumes were greater in the bilateral caudate, prefrontal lobe and ventral temporal lobe. The summary Asperger syndrome map indicated lower grey matter volumes in the bilateral amygdala/hippocampal gyrus and prefrontal lobe, left occipital gyrus, right cerebellum, putamen and precuneus
Zhu, Ce; Li, Fei; Wong, May Chun Mei; Feng, Xi-Ping; Lu, Hai-Xia; Xu, Wei
Numerous studies have investigated the associations between herpesviruses and chronic periodontitis; however, the results remain controversial. To derive a more precise estimation, a meta-analysis on all available studies was performed to identify the association between herpesviruses and chronic periodontitis. A computerized literature search was conducted in December 2014 to identify eligible case-control studies from the PUBMED and EMBASE databases according to inclusion and exclusion criteria. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were used to assess the association between herpesviruses and risk of chronic periodontitis. A fixed or random effects model was determined based on a heterogeneity test. Sensitivity analysis was conducted to investigate stability and reliability. Publication bias was investigated using the Begg rank correlation test and Egger's funnel plot. Ten eligible studies were included to investigate the association between Epstein-Barr virus (EBV) and chronic periodontitis. The results showed that EBV has a significant association with chronic periodontitis compared with periodontally healthy group (OR = 5.74, 95% CI = 2.53-13.00, Pchronic periodontitis was analyzed in 10 studies. The pooled result showed that HCMV also has a significant association with chronic periodontitis (OR = 3.59, 95% CI = 1.41-9.16, P = 0.007). Similar results were found in the sensitivity analyses. No significant publication bias was observed. Two eligible studies were included to investigate the association between herpes simplex virus (HSV) and chronic periodontitis risk. The association between HSV and chronic periodontitis was inconclusive (OR = 2.81 95% CI = 0.95-8.27, P = 0.06). Only one included study investigated the association between human herpesvirus 7 (HHV-7) and chronic periodontitis risk (OR = 1.00, 95% CI = 0.21-4.86). The findings of this meta-analysis suggest that two members of the herpesvirus family, EBV
Full Text Available Vitamin D is suggested to have protective effects against type 1 diabetes. However, the results from observational studies have been inconsistent. We aimed to examine their association by conducting a meta-analysis of observational studies. Multiple databases were searched in June 2013 to identify relevant studies including both case-control and cohort studies. Either a fixed- or random-effects model was used to calculate the pooled risk estimate. We identified eight studies (two cohort studies and six case-control studies on vitamin D intake during early life and three studies (two cohort studies and one case-control study on maternal vitamin D intake during pregnancy. The pooled odds ratio for type 1 diabetes comparing vitamin D supplementation with non-supplementation during early life was 0.71 (95% confidence interval [CI], 0.51–0.98. Similar results were observed in the case-control subgroup analysis but not in the cohort subgroup analysis. The pooled odds ratio with maternal intake of vitamin D during pregnancy was 0.95 (95% CI, 0.66–1.36. In conclusion, vitamin D intake during early life may be associated with a reduced risk of type 1 diabetes. However, there was not enough evidence for an association between maternal intake of vitamin D and risk of type 1 diabetes in the offspring.
Full Text Available This study aimed to elucidate the effects of cholecystectomy on the risk of colorectal cancer (CRC by conducting a meta-analysis of 10 cohort studies.The eligible cohort studies were selected by searching the PubMed and EMBASE databases from their origination to June 30, 2016, as well as by consulting the reference lists of the selected articles. Two authors individually collected the data from the 10 papers. When the data showed marked heterogeneity, we used a random-effects model to estimate the overall pooled risk; otherwise, a fixed effects model was employed.The final analysis included ten cohort studies. According to the Newcastle-Ottawa Scale (NOS, nine papers were considered high quality. After the data of these 9 studies were combined, an increased risk of CRC was found among the individuals who had undergone cholecystectomy (risk ratio (RR 1.22; 95% confidence interval (CI 1.08-1.38. In addition, we also found a promising increased risk for colon cancer (CC (RR 1.30, 95% CI 1.07-1.58, but no relationship between cholecystectomy and rectum cancer (RC (RR 1.09; 95% CI 0.89-1.34 was observed. Additionally, in the sub-group analysis of the tumor location in the colon, a positive risk for ascending colon cancer (ACC was found (RR 1.18, 95% CI 1.11-1.26. After combining the ACC, transverse colon cancer (TCC, sigmoid colon cancer (SCC and descending colon cancer (DCC patients, we found a positive relationship with cholecystectomy (RR 1.18, 95% CI 1.11-1.26. Furthermore, after combining the ACC and DCC patients, we also found a positive relationship with cholecystectomy (RR 1.28; 95% CI 1.11-1.26 in the sub-group analysis. In an additional sub-group analysis of patients from Western countries, there was a positive relationship between cholecystectomy and the risk of CRC (RR 1.20; 95% CI 1.05-1.36. Furthermore, a positive relationship between female gender and CRC was also found (RR 1.17; 95% CI 1.03-1.34. However, there was no relationship
Full Text Available The potential role of coffee consumption in the development of various types of cancer has been extensively investigated in epidemiologic studies. How coffee consumption may modulate risk of gastric cancer, however, remains a subject open for investigation. To better quantify this relation, we quantitatively summarized evidence from prospective studies. Eligible studies were identified on PubMed and Embase databases. The summary risk estimates were obtained using the random-effects model. Subgroup, sensitivity and dose-response analyses were conducted. The present meta-analysis included 12 prospective cohort studies. A pooled analysis of these studies suggested that coffee consumption (highest vs. lowest consumption was not associated with risk of gastric cancer (RR = 1.12, 95% CI = 0.93–1.36. In the subgroup analysis, significant increased risk was detected in the U.S. studies (RR = 1.36, 95% CI = 1.06–1.74 and in the studies with <10 years of follow-up (RR = 1.24, 95% CI = 1.00–1.54, and the greatest increase in risk was observed in those studies without adjustment for smoking (RR = 1.48, 95% CI = 1.13–1.93. There was some evidence of publication bias (P for Egger’s test = 0.03. Cumulative evidence from prospective studies suggests that coffee consumption is not associated with risk of gastric cancer. The observed positive results may be confounded by smoking and need further investigation.
Zhang, Juan; Zhou, Bin; Hao, Chuanzheng
In epidemiologic studies, association between coffee consumption and esophageal cancer risk is inconsistent. The aim of tjis study was to evaluate the effect of coffee on esophageal cancer by combining several similar studies. We conducted a meta-analysis for association of coffee intake and esophageal cancer incidence. Eleven studies, including 457,010 participants and 2628 incident cases, were identified. A relative risk (RR, for cohort study) or odds ratio (OR, for case-control study) of heavy coffee drinkers was calculated, compared with light coffee drinkers or non-drinkers. The analysis was also stratified by cancer types (esophageal squamous cell carcinoma and esophageal adenocarcinoma), sex, and geographic region. The summarized OR of having esophageal cancer in heavy coffee drinkers was 0.93 (95% confidence interval [CI]: 0.73-1.12), compared with light coffee drinkers. When stratified by sex, pathologic type of esophageal cancer, and type of epidemiologic study, we did not find any association of coffee consumption and esophageal cancer incidence. However, an inverse association between coffee consumption and incidence of esophageal cancer was found in East Asia participants with OR of 0.64 (95% CI: 0.44-0.83), but not in Euro-America participants (OR = 1.05; 95% CI: 0.81-1.29). There is a protective role of coffee consumption against esophageal cancer in East Asians, but not in Euro-Americans.
Guo, K; Liang, Z; Liu, L; Li, F; Wang, H
The aim of the study was to assess the association between total flavonoids/flavonoid subclasses intake and prostate cancer risk. Several databases were searched to select eligible studies with predefined criteria. Risk ratios (RRs) with 95% confidence intervals (CIs) were used as the effect size. Publication bias and sensitivity analysis were performed. A total of five studies including four prospective cohort studies and one case-control study were included in the meta-analysis. The pooled result demonstrated a significantly increased risk of prostate cancer with higher intake of total flavonoids (RR = 1.12, 95% CI: 1.02-1.23, P = 0.013). However, sensitivity analysis indicated that there lacked a significant association after removing the study of Wang et al. (RR = 1.17, 95% CI: 0.94-1.46). Subgroup analysis stratified by flavonoids subclasses found that higher intake of anthocyanidins and flavan-3-ols were significantly associated with increased prostate cancer risk (RR = 1.12, 95% CI: 1.03-1.21, P = 0.011; RR = 1.21, 95% CI: 1.10-1.32, P flavonoids may not be associated with prostate cancer risk. © 2016 Blackwell Verlag GmbH.
Cheng, Min; Lu, Xiangfeng; Huang, Jianfeng; Zhang, Shu; Gu, Dongfeng
Electrocardiographic PR interval prolongation is considered a benign condition, but recent studies have challenged the notion by demonstrating that prolonged PR interval is associated with an increased risk of atrial fibrillation (AF). The purpose of this study was to perform a meta-analysis of prospective cohort studies to evaluate the evidence supporting an association of prolonged PR interval with AF incidence. We searched the MEDLINE and EMBASE database (from inception to May 2014) supplemented by manual searches of references of relevant retrieved articles. Prospective cohort studies were included with hazard ratio (HR) of prolonged PR interval for incident AF. The search strategy yielded 6 cohort studies meeting eligibility criteria. A total of 328,932 participants were included, with 14,191 participants suffering from AF during follow-up. Pooled HRs of prolonged PR interval for incident AF was 1.30 (95% CI: 1.13 to 1.49) using random-effect model (I(2) = 30%). There was a significant difference of combined HRs between studies with and without adjustment for taking of AV nodal blocking agents in subgroup analysis. Sensitivity analysis supported the robustness of the results. Prolonged PR interval is not a totally benign condition but an independent risk factor for AF incidence. The mechanisms underlying the association of prolonged PR interval with AF incidence need further research. © 2014 Wiley Periodicals, Inc.
Rebecca J. Von Der Heide
Full Text Available Studies of nonhuman primates have reported face sensitive patches in the ventral anterior temporal lobes (ATL. In humans, ATL resection or damage causes an associative prosopagnosia in which face perception is intact but face memory is compromised. Some fMRI studies have extended these findings using famous and familiar faces. However, it is unclear whether these regions in the human ATL are in locations comparable to those reported in non-human primates, typically using unfamiliar faces. We present the results of two studies of person memory: a meta-analysis of existing fMRI studies and an empirical fMRI study using optimized imaging parameters. Both studies showed left-lateralized ATL activations to familiar individuals while novel faces activated the right ATL. Activations to famous faces were quite ventral, similar to what has been reported in monkeys. These findings suggest that face memory-sensitive patches in the human ATL are in the ventral/polar ATL.
Song, Bo; Liu, Kai; Gao, Yuan; Zhao, Lu; Fang, Hui; Li, Yusheng; Pei, Lulu; Xu, Yuming
The aim of current meta-analysis was to investigate the relation between lycopene and risk of cardiovascular diseases (CVD). Studies concerning about the association between lycopene and risk of CVD were searched on Pubmed, Embase, and Web of Science from inception to October 2016. A total of 14 eligible studies were identified. A significantly inverse association with a pooled risk ratio (RR) of 0.83 (95% CI: 0.76-0.90) was shown between lycopene exposure and risk of CVD. Findings were similar restricting to dietary studies (RR = 0.87, 95% CI = 0.79-0.96) and biomarker studies (RR = 0.74, 95% CI = 0. 62-0.87).Dietary lycopene intake was statistically significant for coronary heart disease (CHD) (RR: 0.87; 95% CI: 0.76-0.98) and stroke (RR: 0.83; 95% CI: 0.69-0.96).The pooled risk estimate was generally similar for lycopene biomarker concentrations, but the association was only statistically significant for stroke (RR: 0.65; 95% CI: 0.42-0.87). Subgroup analyses showed that retrospective and low quality studies were statistically significant sources of heterogeneity. Higher lycopene exposure is inversely associated with a lower risk of CVD. Further well-designed randomized clinical trials are required to assess the role of lycopene on CVD. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
van der Vijgh, Benny; Beun, Robbert-Jan; Van Rood, Maarten; Werkhoven, Peter
Digital games have been used as stressors in a range of disciplines for decades. Nonetheless, the underlying characteristics of these stressors and the study in which the stressor was applied are generally not recognized for their moderating effect on the measured physiological stress responses. We have therefore conducted a meta-analysis that analyzes the effects of characteristics of digital game stressors and study design on heart rate, systolic and diastolic blood pressure, in studies carried out from 1976 to 2012. In order to assess the differing quality between study designs, a new scale is developed and presented, coined reliability of effect size. The results show specific and consistent moderating functions of both game and study characteristics, on average accounting for around 43%, and in certain cases up to 57% of the variance found in physiological stress responses. Possible cognitive and physiological processes underlying these moderating functions are discussed, and a new model integrating these processes with the moderating functions is presented. These findings indicate that a digital game stressor does not act as a stressor by virtue of being a game, but rather derives its stressor function from its characteristics and the methodology in which it is used. This finding, together with the size of the associated moderations, indicates the need for a standardization of digital game stressors. © 2015 Society for Psychophysiological Research.
Shang, Yonggang; Yi, Shanhong; Cui, Dong; Han, Guangwei; Liu, Chengcheng
Vitamin E intake may reduce the risk of renal cell carcinoma, but the results were inconsistent. Hence, we conducted a meta-analysis to assess the association between dietary vitamin E intake and the risk of renal cell carcinoma. We searched PubMed to identify the relevant case-control studies up to June 2014. Reference lists of retrieved articles were also reviewed. Odds ratios and corresponding 95% confidence intervals were used to estimate the association between dietary vitamin E intake and the risk of renal cell carcinoma. We identified 7 case-control studies regarding dietary vitamin E intake and risk of renal cell carcinoma, involving 5789 cases and 14866 controls. The odds ratio of renal cell carcinoma for the highest compared with the lowest dietary vitamin E intake was 0.75 (95% confidence interval: 0.59-0.91), and heterogeneity was observed across studies. The association between dietary vitamin E intake and the risk of renal cell carcinoma was not significantly differed by gender, but this association were inconsistent in the North American and European populations. Our study provided a evidence that there was a significant inverse association of dietary vitamin E intake with risk of renal cell carcinoma. However, this finding was based on the case-control studies, more well-designed cohort studies are needed. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
Corrigan, Patrick W; Morris, Scott B; Michaels, Patrick J; Rafacz, Jennifer D; Rüsch, Nicolas
Public stigma and discrimination have pernicious effects on the lives of people with serious mental illnesses. Given a plethora of research on changing the stigma of mental illness, this article reports on a meta-analysis that examined the effects of antistigma approaches that included protest or social activism, education of the public, and contact with persons with mental illness. The investigators heeded published guidelines for systematic literature reviews in health care. This comprehensive and systematic review included articles in languages other than English, dissertations, and population studies. The search included all articles from the inception of the databases until October 2010. Search terms fell into three categories: stigma, mental illness (such as schizophrenia and depression), and change program (including contact and education). The search yielded 72 articles and reports meeting the inclusion criteria of relevance to changing public stigma and sufficient data and statistics to complete analyses. Studies represented 38,364 research participants from 14 countries. Effect sizes were computed for all studies and for each treatment condition within studies. Comparisons between effect sizes were conducted with a weighted one-way analysis of variance. Overall, both education and contact had positive effects on reducing stigma for adults and adolescents with a mental illness. However, contact was better than education at reducing stigma for adults. For adolescents, the opposite pattern was found: education was more effective. Overall, face-to-face contact was more effective than contact by video. Future research is needed to identify moderators of the effects of both education and contact.
Janket, S-J; Wightman, A; Baird, A E; Van Dyke, T E; Jones, J A
Previous analyses regarding effects of periodontal treatment on glycemic control included studies where causal association might not be assumed, or the results were reported non-quantitatively. We initiated this meta-analysis of 10 intervention studies to quantify the effects of periodontal treatment on HbA1c level among diabetic patients, to explore possible causes for the discrepant reports, and to make recommendations for future studies. Data sources were MEDLINE (January, 1980, to January, 2005), the EBMR, Cochrane Register, and bibliographies of the published articles. Three investigators extracted data regarding intervention, outcomes, and effect size. A total of 456 patients was included in this analysis, with periodontal treatment as predictor and the actual change in hemoglobin A1c level as the outcome. The weighted average decrease in actual HbA1c level was 0.38% for all studies, 0.66% when restricted to type 2 diabetic patients, and 0.71% if antibiotics were given to them. However, none was statistically significant.
Chang, Ke-Vin; Hsu, Tsai-Hsuan; Wu, Wei-Ting; Huang, Kuo-Chin; Han, Der-Sheng
to explore whether sarcopenia is associated with depression. electronic literature databases from PubMed, Scopus, Embase and Google Scholar were searched. A systematic review and meta-analysis of observational studies was conducted. community and outpatient clinic. people with and without diagnoses of sarcopenia. outcome measures of depression. about 15 articles were included, 5 of which were retrieved for narrative review. The crude odds ratios (ORs) between sarcopenia and depression were extracted from the remaining 10 studies, 6 of which also included adjusted ORs. Sarcopenia was associated with depression without adjusting covariates (crude OR, 1.640; 95% confidence interval (CI), 1.247-2.155). After adjusting for potential confounders such as age, gender, cognitive performance and physical activity, sarcopenia still demonstrated a significant positive association with depression (adjusted OR, 1.821; 95% CI, 1.160-2.859). A stratified analysis showed that the studies that used bioelectrical impedance analysis for measurement of body composition tended to have an elevated association between sarcopenia and depression compared with those that used dual-energy X-ray absorptiometry or equation estimation. sarcopenia was independently associated with depression. The causal relationship between the two clinical conditions requires future validation with cohort studies. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.All rights reserved. For permissions, please email: email@example.com
Noar, Seth M; Hall, Marissa G; Francis, Diane B; Ribisl, Kurt M; Pepper, Jessica K; Brewer, Noel T
To inform international research and policy, we conducted a meta-analysis of the experimental literature on pictorial cigarette pack warnings. We systematically searched 7 computerised databases in April 2013 using several search terms. We also searched reference lists of relevant articles. We included studies that used an experimental protocol to test cigarette pack warnings and reported data on both pictorial and text-only conditions. 37 studies with data on 48 independent samples (N=33,613) met criteria. Two independent coders coded all study characteristics. Effect sizes were computed from data extracted from study reports and were combined using random effects meta-analytic procedures. Pictorial warnings were more effective than text-only warnings for 12 of 17 effectiveness outcomes (all pnegative pack attitudes and negative smoking attitudes and (4) more effectively increased intentions to not start smoking and to quit smoking. Participants also perceived pictorial warnings as being more effective than text-only warnings across all 8 perceived effectiveness outcomes. The evidence from this international body of literature supports pictorial cigarette pack warnings as more effective than text-only warnings. Gaps in the literature include a lack of assessment of smoking behaviour and a dearth of theory-based research on how warnings exert their effects. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Soroush, Ali; Shamsi, Mohammadbagher; Izadi, Neda; Heydarpour, Behzad; Samadzadeh, Soheila; Shahmohammadi, Afshar
Considering the importance of musculoskeletal disorders (MSDs) as one of the health consequences of job stress among nurses and significant contradictions in prevalence in different parts of the body, this study was carried out to determine the prevalence of MSDs among Iranian nurses. All published studies from June 2000 until June 2015 were considered in reliable databases such as PubMed, Google Scholar, Google search, Scopus, ScienceDirect, and Persian databases such as SID, Iran Medex, and Magiran. These studies, after quality control, were entered into meta-analysis using the random effects model, a total of 41 papers were assessed between 2004 and 2015. The prevalence rate of these disorders was 60.98%, 47.76%, 46.53%, 44.64%, 42.8%, 36.8%, 24.61%, and 17.5%, respectively, obtained for the back, neck, knees, upper back, ankles, shoulders, hands, hips, thighs, and elbows. Prevalence of MSDs will lead to high costs of medical, absenteeism from work, or even unemployment. Due to high prevalence of these disorders among Iranian nurses, providing effective training in the field of ergonomics and undergoing appropriate exercises are necessary to control it.
Full Text Available Lumbar disc removal is currently the standard treatment for lumbar disc herniation. No consensus has been achieved whether aggressive disc resection with curettage (discectomy versus conservative removal of the offending disc fragment alone (sequestrectomy provides better outcomes. This study aims to compare the reherniation rate and clinical outcomes between discectomy and sequestrectomy by literature review and a meta-analysis.A systematic search of PubMed, Medline, Embase and the Cochrane Library was performed up to June 1, 2014. Outcomes of interest assessing the two techniques included demographic and clinical baseline characteristics, perioperative variables, complications, recurrent herniation rate and post-operative functional outcomes.Twelve eligible trials evaluating discectomy vs sequestrectomy were identified including one randomized controlled study, five prospective and six retrospective comparative studies. By contrast to discectomy, sequestrectomy was associated with significantly less operative time (p<0.001, lower visual analogue scale (VAS for low back pain (p<0.05, less post-operative analgesic usage (p<0.05 and better patients' satisfaction (p<0.05. Recurrent herniation rate, reoperation rate, intraoperative blood loss, hospitalization duration and VAS for sciatica were without significant difference.According to our pooled data, sequestrectomy entails equivalent reherniation rate and complications compared with discectomy but maintains a lower incidence of recurrent low back pain and higher satisfactory rate. High-quality prospective randomized controlled trials are needed to firmly assess these two procedures.
van der Meij, Leander; Schaveling, Jaap; van Vugt, Mark
This article examines the role of basal testosterone as a potential biological marker of leadership and hierarchy in the workplace. First, we report the result of a study with a sample of male employees from different corporate organizations in the Netherlands (n=125). Results showed that employees with higher basal testosterone levels reported a more authoritarian leadership style, but this relationship was absent among those who currently held a real management position (i.e., they had at least one subordinate). Furthermore, basal testosterone levels were not different between managers and non-managers, and testosterone was not associated with various indicators of status and hierarchy such as number of subordinates, income, and position in the organizational hierarchy. In our meta-analysis (second study), we showed that basal testosterone levels were not associated with leadership in men nor in women (9 studies, n=1103). Taken together, our findings show that basal testosterone is not associated with having a leadership position in the corporate world or related to leadership styles in leaders. We suggest that basal testosterone could play a role in acquiring leadership positions through dominant and authoritarian behavior. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Full Text Available OBJECTIVES: A common method for conducting a quantitative systematic review (QSR for observational studies related to nutritional epidemiology is the “highest versus lowest intake” method (HLM, in which only the information concerning the effect size (ES of the highest category of a food item is collected on the basis of its lowest category. However, in the interval collapsing method (ICM, a method suggested to enable a maximum utilization of all available information, the ES information is collected by collapsing all categories into a single category. This study aimed to compare the ES and summary effect size (SES between the HLM and ICM. METHODS: A QSR for evaluating the citrus fruit intake and risk of pancreatic cancer and calculating the SES by using the HLM was selected. The ES and SES were estimated by performing a meta-analysis using the fixed-effect model. The directionality and statistical significance of the ES and SES were used as criteria for determining the concordance between the HLM and ICM outcomes. RESULTS: No significant differences were observed in the directionality of SES extracted by using the HLM or ICM. The application of the ICM, which uses a broader information base, yielded more-consistent ES and SES, and narrower confidence intervals than the HLM. CONCLUSIONS: The ICM is advantageous over the HLM owing to its higher statistical accuracy in extracting information for QSR on nutritional epidemiology. The application of the ICM should hence be recommended for future studies.
LI, Xinli; XU, Jiuhong
Epidemiological studies support a protective role of lycopene against stroke occurrence or mortality, but the results have been conflicting. We conducted a meta-analysis to assess the relationship between dietary or circulating lycopene and stroke risk (including stroke occurrence or mortality). Relevant papers were collected by screening the PubMed database through October 2013. Only prospective studies providing relative risk estimates with 95% confidence intervals for the association between lycopene and stroke were included. A random-effects model was used to calculate the pooled estimate. Subgroup analysis was conducted to investigate the effects of various factors on the final results. The pooled analysis of seven prospective studies, with 116,127 participants and 1,989 cases, demonstrated that lycopene decreased stroke risk by 19.3% (RR = 0.807, 95% CI = 0.680–0.957) after adjusting for confounding factors. No heterogeneity was observed (p = 0.234, I2 = 25.5%). Circulating lycopene, not dietary lycopene, was associated with a statistically significant decrease in stroke risk (RR = 0.693, 95% CI = 0.503–0.954). Lycopene could protect European, or males against stroke risk. Duration of follow-up had no effect on the final results. There was no evidence of publication bias. Lycopene, especially circulating lycopene, is negatively associated with stroke risk. PMID:24848940
Simmons, Sarah M; Hicks, Anne; Caird, Jeff K
A systematic review and meta-analysis of naturalistic driving studies involving estimates of safety-critical event risk associated with handheld device use while driving is described. Fifty-seven studies identified from targeted databases, journals and websites were reviewed in depth, and six were ultimately included. These six studies, published between 2006 and 2014, encompass seven sets of naturalistic driver data and describe original research that utilized naturalistic methods to assess the effects of distracting behaviors. Four studies involved non-commercial drivers of light vehicles and two studies involved commercial drivers of trucks and buses. Odds ratios quantifying safety-critical event (SCE) risk associated with talking, dialing, locating or answering, and texting or browsing were extracted. Stratified meta-analysis of pooled odds ratios was used to estimate SCE risk by distraction type; meta-regression was used to test for sources of heterogeneity. The results indicate that tasks that require drivers to take their eyes off the road, such as dialing, locating a phone and texting, increase SCE risk to a greater extent than tasks that do not require eyes off the road such as talking. Although talking on a handheld device did not increase SCE risk, further research is required to determine whether it indirectly influences SCE risk (e.g., by encouraging other cell phone activities). In addition, a number of study biases and quality issues of naturalistic driving studies are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.
Zhang, Cheng; Zhong, Min
Several meta-analyses and reports from the World Cancer Research Fund supported a risk association between alcohol consumption and colorectal cancer (CRC). However, the association for beer consumption, the common type of alcoholic beverage, remains unclear. We identified studies by a literature search of PUBMED and EMBASE through 30 June 2014. Summary relative risks (SRRs) with their 95% CIs were calculated with a fixed or random effects model. Twelve case-control and nine cohort studies were included. Compared with non-alcohol drinkers or non-beer drinkers, any beer drinkers were associated with an increased risk of CRC (SRR = 1.20, 95% CI, 1.06-1.37; p(heterogeneity) beer drinking was related to increased risk of CRC (SRR = 1.37, 95% CI 1.26-1.49), while light or moderate beer drinking was not. The dose-response analysis demonstrated that an increase of one drink per day in beer consumption was related to an increased risk of CRC (SRR = 1.13, 95% CI, 1.06-1.21). There was evidence of a potential nonlinear association between beer intake and CRC incidence (p = 0.002 for nonlinearity). The results from this meta-analysis suggest that heavy (≥ 2 drinks/day) beer drinking may be associated with increased CRC risk. More researches with improved control of confounding and actual measurement of beer consumption are needed to confirm these findings.
Mulatu, A.; Florax, R.J.G.M. [Department of Spatial Economics, Master-point and Tinbergen Institute, Vrije Universiteit, Amsterdam (Netherlands); Withagen, C.A.A.M. [Department of Economics and CentER, Tilburg University, Tilburg (Netherlands)
The potential relationship between domestic environmental regulation and international competitiveness has evoked various speculations. The common neoclassical train of thought is that strict environmental regulation is detrimental to the competitiveness of industry, and that it induces phenomena such as ecological dumping, ecological capital flight, and regulatory 'chill' in environmental standards. A different view is that strict environmental regulation triggers industry's innovation potential, and subsequently increases its competitiveness. The impact of environmental regulation on competitiveness has been analyzed in terms of international capital movements, new firm formation, and international trade. This paper focuses on a statistically rigorous analysis of international trade studies, using a technique that is known as meta-analysis. The paper presents a statistically supported evaluation of the literature, in order to assess what the main conclusions regarding the relationship between environmental regulation and competitiveness are when it comes to studies on international trade flows. The synthesis of the literature is subsequently used to present guidelines for future primary research in this area.
Mulatu, A.; Florax, R.J.G.M.; Withagen, C.A.A.M.
The potential relationship between domestic environmental regulation and international competitiveness has evoked various speculations. The common neoclassical train of thought is that strict environmental regulation is detrimental to the competitiveness of industry, and that it induces phenomena such as ecological dumping, ecological capital flight, and regulatory 'chill' in environmental standards. A different view is that strict environmental regulation triggers industry's innovation potential, and subsequently increases its competitiveness. The impact of environmental regulation on competitiveness has been analyzed in terms of international capital movements, new firm formation, and international trade. This paper focuses on a statistically rigorous analysis of international trade studies, using a technique that is known as meta-analysis. The paper presents a statistically supported evaluation of the literature, in order to assess what the main conclusions regarding the relationship between environmental regulation and competitiveness are when it comes to studies on international trade flows. The synthesis of the literature is subsequently used to present guidelines for future primary research in this area
Patil, S. S.; Suresh, K. P.; Saha, S.; Prajapati, A.; Hemadri, D.; Roy, P.
Aim: The aim of the study was to determine the overall prevalence of classical swine fever (CSF) in pigs in India, through a systematic review and meta-analysis of published data. Materials and Methods: Consortium for e-Resources in Agriculture, India, Google Scholar, PubMed, annual reports of All India Coordinated Research Project on Animal Disease Monitoring and Surveillance, and All India Animal Disease database of NIVEDI (NADRES) were used for searching and retrieval of CSF prevalence data (seroprevalence, virus antigen, and virus nucleic acid detection) in India using a search strategy combining keywords and related database-specific subject terms from January 2011 to December 2015 in English only. Results: A total of 22 data reports containing 6,158 samples size from 18 states of India were used for the quantitative synthesis, and overall 37% (95% confidence interval [CI]=0.24, 0.51) CSF prevalence in India was estimated. The data were classified into 4 different geographical zones of the country: 20% (95% CI=0.05, 0.55), 31% (95% CI=0.18, 0.47), 55% (95% CI=0.32, 0.76), and 34% (95% CI=0.14, 0.62). CSF prevalence was estimated in northern, eastern, western, and southern regions, respectively. Conclusion: This study indicates that overall prevalence of CSF in India is much lower than individual published reports. PMID:29657420
Kivimäki, M; Singh-Manoux, A; Nyberg, S; Jokela, M; Virtanen, M
Job strain, the most widely used indicator of work stress, is a risk factor for obesity-related disorders such as cardiovascular disease and type 2 diabetes. However, the extent to which job strain is related to the development of obesity itself has not been systematically evaluated. We carried out a systematic review (PubMed and Embase until May 2014) and meta-analysis of cohort studies to address this issue. Eight studies that fulfilled inclusion criteria showed no overall association between job strain and the risk of weight gain (pooled odds ratio for job strain compared with no job strain 1.04, 95% confidence interval (CI) 0.99-1.09, NTotal=18 240) or becoming obese (1.00, 95% CI 0.89-1.13, NTotal=42 222). In addition, a reduction in job strain over time was not associated with lower obesity risk (1.13, 95% CI 0.90-1.41, NTotal=6507). These longitudinal findings do not support the hypothesis that job strain is an important risk factor for obesity or a promising target for obesity prevention.
Yin, Xin-Hai; Huang, Guang-Lei; Lin, Du-Ren; Wan, Cheng-Cheng; Wang, Ya-Dong; Song, Ju-Kun; Xu, Ping
Background Many observational studies have shown that exposure to fluoride in drinking water is associated with hip fracture risk. However, the findings are varied or even contradictory. In this work, we performed a meta-analysis to assess the relationship between fluoride exposure and hip fracture risk. Methods PubMed and EMBASE databases were searched to identify relevant observational studies from the time of inception until March 2014 without restrictions. Data from the included studies w...
Berndt, Sonja I.; Camp, Nicola J.; Skibola, Christine F.; Vijai, Joseph; Wang, Zhaoming; Gu, Jian; Nieters, Alexandra; Kelly, Rachel S.; Smedby, Karin E.; Monnereau, Alain; Cozen, Wendy; Cox, Angela; Wang, Sophia S.; Lan, Qing; Teras, Lauren R.; Machado, Moara; Yeager, Meredith; Brooks-Wilson, Angela R.; Hartge, Patricia; Purdue, Mark P.; Birmann, Brenda M.; Vajdic, Claire M.; Cocco, Pierluigi; Zhang, Yawei; Giles, Graham G.; Zeleniuch-Jacquotte, Anne; Lawrence, Charles; Montalvan, Rebecca; Burdett, Laurie; Hutchinson, Amy; Ye, Yuanqing; Call, Timothy G.; Shanafelt, Tait D.; Novak, Anne J.; Kay, Neil E.; Liebow, Mark; Cunningham, Julie M.; Allmer, Cristine; Hjalgrim, Henrik; Adami, Hans-Olov; Melbye, Mads; Glimelius, Bengt; Chang, Ellen T.; Glenn, Martha; Curtin, Karen; Cannon-Albright, Lisa A.; Diver, W Ryan; Link, Brian K.; Weiner, George J.; Conde, Lucia; Bracci, Paige M.; Riby, Jacques; Arnett, Donna K.; Zhi, Degui; Leach, Justin M.; Holly, Elizabeth A.; Jackson, Rebecca D.; Tinker, Lesley F.; Benavente, Yolanda; Sala, Núria; Casabonne, Delphine; Becker, Nikolaus; Boffetta, Paolo; Brennan, Paul; Foretova, Lenka; Maynadie, Marc; McKay, James; Staines, Anthony; Chaffee, Kari G.; Achenbach, Sara J.; Vachon, Celine M.; Goldin, Lynn R.; Strom, Sara S.; Leis, Jose F.; Weinberg, J. Brice; Caporaso, Neil E.; Norman, Aaron D.; De Roos, Anneclaire J.; Morton, Lindsay M.; Severson, Richard K.; Riboli, Elio; Vineis, Paolo; Kaaks, Rudolph; Masala, Giovanna; Weiderpass, Elisabete; Chirlaque, María- Dolores; Vermeulen, Roel C. H.; Travis, Ruth C.; Southey, Melissa C.; Milne, Roger L.; Albanes, Demetrius; Virtamo, Jarmo; Weinstein, Stephanie; Clavel, Jacqueline; Zheng, Tongzhang; Holford, Theodore R.; Villano, Danylo J.; Maria, Ann; Spinelli, John J.; Gascoyne, Randy D.; Connors, Joseph M.; Bertrand, Kimberly A.; Giovannucci, Edward; Kraft, Peter; Kricker, Anne; Turner, Jenny; Ennas, Maria Grazia; Ferri, Giovanni M.; Miligi, Lucia; Liang, Liming; Ma, Baoshan; Huang, Jinyan; Crouch, Simon; Park, Ju-Hyun; Chatterjee, Nilanjan; North, Kari E.; Snowden, John A.; Wright, Josh; Fraumeni, Joseph F.; Offit, Kenneth; Wu, Xifeng; de Sanjose, Silvia; Cerhan, James R.; Chanock, Stephen J.; Rothman, Nathaniel; Slager, Susan L.
Chronic lymphocytic leukemia (CLL) is a common lymphoid malignancy with strong heritability. To further understand the genetic susceptibility for CLL and identify common loci associated with risk, we conducted a meta-analysis of four genome-wide association studies (GWAS) composed of 3,100 cases and 7,667 controls with follow-up replication in 1,958 cases and 5,530 controls. Here we report three new loci at 3p24.1 (rs9880772, EOMES, P=2.55 × 10−11), 6p25.2 (rs73718779, SERPINB6, P=1.97 × 10−8) and 3q28 (rs9815073, LPP, P=3.62 × 10−8), as well as a new independent SNP at the known 2q13 locus (rs9308731, BCL2L11, P=1.00 × 10−11) in the combined analysis. We find suggestive evidence (P<5 × 10−7) for two additional new loci at 4q24 (rs10028805, BANK1, P=7.19 × 10−8) and 3p22.2 (rs1274963, CSRNP1, P=2.12 × 10−7). Pathway analyses of new and known CLL loci consistently show a strong role for apoptosis, providing further evidence for the importance of this biological pathway in CLL susceptibility. PMID:26956414
Xu, Chang; Niu, Yuming; Wu, Junyi; Gu, Huiyun; Zhang, Chao
To compare and analyze the characteristics and functions of software applications for network meta-analysis (NMA). PubMed, EMbase, The Cochrane Library, the official websites of Bayesian inference Using Gibbs Sampling (BUGS), Stata and R, and Google were searched to collect the software and packages for performing NMA; software and packages published up to March 2016 were included. After collecting the software, packages, and their user guides, we used the software and packages to calculate a typical example. All characteristics, functions, and computed results were compared and analyzed. Ten types of software were included, including programming and non-programming software. They were developed mainly based on Bayesian or frequentist theory. Most types of software have the characteristics of easy operation, easy mastery, exact calculation, or excellent graphing. However, there was no single software that performed accurate calculations with superior graphing; this could only be achieved through the combination of two or more types of software. This study suggests that the user should choose the appropriate software according to personal programming basis, operational habits, and financial ability. Then, the choice of the combination of BUGS and R (or Stata) software to perform the NMA is considered. © 2017 Chinese Cochrane Center, West China Hospital of Sichuan University and John Wiley & Sons Australia, Ltd.
Full Text Available Vortex pumps can impel solid-containing fluids and are therefore widely applied, from wastewater transport to the food industry. Despite constant efforts to improve vortex pumps, however, they have remained relatively inefficient compared to conventional centrifugal pumps. To find an optimized design of vortex pumps, this paper provides a systematic analysis on experimental studies that investigated how variations in geometric parameters influence vortex pump characteristics, in particular the pump head, the pressure coefficient and the efficiency for best point operation. To this end, an extensive literature search was conducted, and eighteen articles with 53 primary investigations were identified and meta-integrated. This showed that it is not yet clarified how vortex pumps operate. Two different assumptions of the underlying operating principle of a vortex pump lead to diverging design principles. From the results of this meta-analysis, we deduce recommendations for a more efficient design of a vortex pump and emphasize further aspects on the underlying operating principle of a vortex pump.
Zhou, Dan; Tang, Weiwei; Wang, Wenyi; Pan, Xiaoyan; An, Han-Xiang; Zhang, Yun
Background. Adenomatous polyposis coli (APC) is widely known as an antagonist of the Wnt signaling pathway via the inactivation of β-catenin. An increasing number of studies have reported that APC methylation contributes to the predisposition to breast cancer (BC). However, recent studies have yielded conflicting results. Methods. Herein, we systematically carried out a meta-analysis to assess the correlation between APC methylation and BC risk. Based on searches of the Cochrane Library, PubMed, Web of Science and Embase databases, the odds ratio (OR) with 95% confidence interval (CI) values were pooled and summarized. Results. A total of 31 articles involving 35 observational studies with 2,483 cases and 1,218 controls met the inclusion criteria. The results demonstrated that the frequency of APC methylation was significantly higher in BC cases than controls under a random effect model (OR = 8.92, 95% CI [5.12-15.52]). Subgroup analysis further confirmed the reliable results, regardless of the sample types detected, methylation detection methods applied and different regions included. Interestingly, our results also showed that the frequency of APC methylation was significantly lower in early-stage BC patients than late-stage ones (OR = 0.62, 95% CI [0.42-0.93]). Conclusion. APC methylation might play an indispensable role in the pathogenesis of BC and could be regarded as a potential biomarker for the diagnosis of BC.
Efficacy of Vitamin D supplements in depression is controversial, awaiting further literature analysis. Biological flaws in primary studies is a possible reason meta-analyses of Vitamin D have failed to demonstrate efficacy. This systematic review and meta-analysis of Vitamin D and depression compared studies with and without biological flaws. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was undertaken through four databases for randomized controlled trials (RCTs). Studies were critically appraised for methodological quality and biological flaws, in relation to the hypothesis and study design. Meta-analyses were performed for studies according to the presence of biological flaws. The 15 RCTs identified provide a more comprehensive evidence-base than previous systematic reviews; methodological quality of studies was generally good and methodology was diverse. A meta-analysis of all studies without flaws demonstrated a statistically significant improvement in depression with Vitamin D supplements (+0.78 CI +0.24, +1.27). Studies with biological flaws were mainly inconclusive, with the meta-analysis demonstrating a statistically significant worsening in depression by taking Vitamin D supplements (-1.1 CI -0.7, -1.5). Vitamin D supplementation (≥800 I.U. daily) was somewhat favorable in the management of depression in studies that demonstrate a change in vitamin levels, and the effect size was comparable to that of anti-depressant medication.
Full Text Available Efficacy of Vitamin D supplements in depression is controversial, awaiting further literature analysis. Biological flaws in primary studies is a possible reason meta-analyses of Vitamin D have failed to demonstrate efficacy. This systematic review and meta-analysis of Vitamin D and depression compared studies with and without biological flaws. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA guidelines. The literature search was undertaken through four databases for randomized controlled trials (RCTs. Studies were critically appraised for methodological quality and biological flaws, in relation to the hypothesis and study design. Meta-analyses were performed for studies according to the presence of biological flaws. The 15 RCTs identified provide a more comprehensive evidence-base than previous systematic reviews; methodological quality of studies was generally good and methodology was diverse. A meta-analysis of all studies without flaws demonstrated a statistically significant improvement in depression with Vitamin D supplements (+0.78 CI +0.24, +1.27. Studies with biological flaws were mainly inconclusive, with the meta-analysis demonstrating a statistically significant worsening in depression by taking Vitamin D supplements (−1.1 CI −0.7, −1.5. Vitamin D supplementation (≥800 I.U. daily was somewhat favorable in the management of depression in studies that demonstrate a change in vitamin levels, and the effect size was comparable to that of anti-depressant medication.
Efficacy of Vitamin D supplements in depression is controversial, awaiting further literature analysis. Biological flaws in primary studies is a possible reason meta-analyses of Vitamin D have failed to demonstrate efficacy. This systematic review and meta-analysis of Vitamin D and depression compared studies with and without biological flaws. The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was un...
Full Text Available BACKGROUND: Previous epidemiological studies have shown that fish consumption may modify the risk of ovarian cancer. However, these studies yielded controversial results. The present meta-analysis was undertaken to evaluate the relationship between fish intake and ovarian cancer risk. METHODS: A literature search was carried out using Pubmed, Embase, and Cochrane Library Central database for all relevant studies up to August 2013. We pooled the relative risks (RR from individual studies using fixed-effect or random-effect model, and carried out heterogeneity and publication bias analyses. RESULTS: A total of 15 (ten case-control, and five cohort studies were included in the present meta-analysis, representing data for 889,033 female subjects and 6,087 ovarian cancer cases. We found that total fish intake was not significantly associated with the risk of ovarian cancer among cohort studies (RR = 1.04 95% CI [0.89, 1.22] as well as case-control studies (RR = 0.90, 95% CI [0.73,1.12]. There was no evidence of publication bias as suggested by Begg's test (P = 0.55 and Egger's test(P = 0.29. CONCLUSIONS: The present meta-analysis showed that total fish consumption was not significantly associated with the risk of ovarian cancer. Further analysis on different fish species and food preparation methods should be conducted in future studies.
Mak, Winnie W S; Mo, Phoenix K H; Ma, Gloria Y K; Lam, Maggie Y Y
The present study conducted a meta-analysis and systematic review on studies evaluating the effectiveness of stigma reduction programs in improving knowledge and reducing negative attitudes towards people living with HIV (PLHIV). Meta-analysis (k = 42 studies) found significant and small effect sizes in the improvement of the participants' knowledge of HIV/AIDS from interventions with (Cohen's d = 0.48, 95% CI [0.30, 0.66]) and without control groups (Cohen's d = 0.42, 95% CI [0.28, 0.57]). Significant and small effect sizes were found in the improvement of the participants' attitudes toward PLHIV from interventions with (Cohen's d = 0.39, 95% CI [0.23, 0.55]) and without control groups (Cohen's d = 0.25, 95% CI [0.11, 0.39]). Significant and small effect sizes were sustained at the follow-up assessments. Subgroup analysis showed that number of intervention sessions, intervention settings, and sample type significantly moderated the effect sizes in the meta-analysis. Findings from the systematic review of 35 studies indicated that most of the included studies showed positive results in reducing negative attitudes toward PLHIV and improving HIV-related knowledge. Most of the included studies tended to have low methodological quality. The present meta-analysis and systematic review indicated that the studies generally found small improvement in HIV-related knowledge and reduction in negative attitudes towards PLHIV among the stigma reduction programs being evaluated. High-quality stigma reduction programs with multidimensional stigma indicators and psychometrically sound outcome measures are highly warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.
van der Meer, Lisette; Costafreda, Sergi; Aleman, André; David, Anthony S
Several studies have investigated the neural correlates of self-reflection. In the paradigm most commonly used to address this concept, a subject is presented with trait adjectives or sentences and asked whether they describe him or her. Functional neuroimaging research has revealed a set of regions known as Cortical Midline Structures (CMS) appearing to be critically involved in self-reflection processes. Furthermore, it has been shown that patients suffering damage to the CMS, have difficulties in properly evaluating the problems they encounter and often overestimate their capacities and performance. Building on previous work, a meta-analysis of published fMRI and PET studies on self-reflection was conducted. The results showed that two areas within the medial prefrontal cortex (MPFC) are important in reflective processing, namely the ventral (v) and dorsal (d) MPFC. In this paper a model is proposed in which the vMPFC is responsible for tagging information relevant for 'self', whereas the dMPFC is responsible for evaluation and decision-making processes in self- and other-referential processing. Finally, implications of the model for schizophrenia and lack of insight are noted. (c) 2009 Elsevier Ltd. All rights reserved.
Richard-Devantoy, Stéphane; Ding, Yang; Turecki, Gustavo; Jollant, Fabrice
Previous studies using a modified Stroop test suggested that suicide attempters, in contrast to depressed patients with no suicidal history, display a particular attentional bias toward suicide-related cues. However, negative results have also been reported. In the present study, we collected new data and pooled them as part of a meta-analysis intended to shed further light on this question. We conducted 1) a cross-sectional study comparing performance on the modified Stroop task for suicide-related, positively-valenced and negatively-valenced words in 33 suicide attempters and 46 patient controls with a history of mood disorders; 2) a systematic review and a meta-analysis of studies comparing performance on the modified Stroop task among patients with vs. without a history of suicidal acts in mood disorders. The cross-sectional study showed no significant difference in interference scores for any type of words between suicide attempters and patient controls. A meta-analysis of four studies, including 233 suicide attempters and 768 patient controls, showed a significant but small attentional bias toward suicide-related words (Hedges'g=0.22, 95%CI [0.06-0.38], Z=2.73, p=0.006), but not negatively-valenced words (Hedges'g=0.06, 95%CI [-0.09-0.22], Z=0.77, p=0.4) in suicide attempters compared to patient controls. Positively-valenced words and healthy controls could not be assessed in the meta-analysis. Our data support a selective information-processing bias among suicide attempters. Indirect evidence suggests that this effect would be state-related and may be a cognitive component of the suicidal crisis. However, we could not conclude about the clinical utility of this Stroop version at this stage. Copyright © 2016 Elsevier B.V. All rights reserved.
Broekhuijsen, Kim; Bernardes, Thomas; van Baaren, Gert-Jan; Tajik, Parvin; Novikova, Natalia; Thangaratinam, Shakila; Boers, Kim; Koopmans, Corine M; Wallace, Kedra; Shennan, Andrew H; Langenveld, Josje; Groen, Henk; van den Berg, Paul P; Mol, Ben Willem J; Franssen, Maureen T M
Like many other research subjects in obstetrics, research on immediate delivery versus expectant monitoring for women with hypertensive disorders of pregnancy faces certain challenges when it comes to interpretation and generalisation of the results; relatively rare outcomes are studied, in a clinically heterogeneous population, while the clinical practice in some countries has dictated that studies in term pregnancy were completed before earlier gestational ages could be studied. This has resulted in multiple smaller studies, some studying surrogate outcome measures, with different in- and exclusion criteria, and without enough power for reliable subgroup analyses. All this complicates the generation of definitive answers and implementation of the results into clinical practice. Performing multiple studies and subsequently pooling their results in a meta-analysis can be a way to overcome the difficulties of studying relatively rare outcomes and subgroups with enough power, as well as a solution to reach a final answer on questions involving an uncertain and possibly harmful intervention. However, in the case of the current studies on delivery versus expectant monitoring in women with hypertensive disorders of pregnancy, differences regarding eligibility criteria, outcome measures and subgroup definitions make it difficult to pool their results in an aggregate meta-analysis. Individual patient data meta-analysis (IPDMA) has the potential to overcome these challenges, because it allows for flexibility regarding the choice of endpoints and standardisation of inclusion and exclusion criteria across studies. In addition, it has more statistical power for informative subgroup analyses. We therefore propose an IPDMA on immediate delivery versus expectant monitoring for hypertensive disorders of pregnancy, and advocate the use of IPDMA for research questions in obstetrics that face similar challenges. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Gao, Yuan; Huang, Changquan; Zhao, Kexiang; Ma, Louyan; Qiu, Xuan; Zhang, Lei; Xiu, Yun; Chen, Lin; Lu, Wei; Huang, Chunxia; Tang, Yong; Xiao, Qian
This study examined whether depression was a risk factor for onset of dementia including Alzheimer's disease (AD), vascular dementia (VD) and any dementia, and mild cognitive impairment (MCI) by using a quantitative meta-analysis of longitudinal studies. EMBASE and MEDLINE were searched for articles published up to February 2011. All studies that examined the relationship between depression and the onset of dementia or MCI were included. Pooled relative risk was calculated using fixed-effects models. Twelve studies met our inclusion criteria for this meta-analysis. All subjects were without dementia or MCI at baseline. Four, two, five, and four studies compared the incidence of AD, VD, any dementia, and MCI between subjects with or without depression, respectively. After pooling all the studies, subjects with depression had higher incidence of AD (relative risk (RR):1.66, 95% confidence interval (CI): 1.29-2.14), VD (RR: 1.89, 95% CI: 1.19-3.01), any dementia (RR: 1.55, 95% CI: 1.31-2.83), and MCI (RR: 1.97, 95% CI: 1.53-2.54) than those without depression. The quantitative meta-analysis showed that depression was a major risk factor for incidence of dementia (including AD, VD, and any dementia) and MCI. Copyright © 2012 John Wiley & Sons, Ltd.
Sulovari, Arvis; Li, Dawei
Genome-wide association studies (GWAS) have successfully identified genes associated with complex human diseases. Although much of the heritability remains unexplained, combining single nucleotide polymorphism (SNP) genotypes from multiple studies for meta-analysis will increase the statistical power to identify new disease-associated variants. Meta-analysis requires same allele definition (nomenclature) and genome build among individual studies. Similarly, imputation, commonly-used prior to meta-analysis, requires the same consistency. However, the genotypes from various GWAS are generated using different genotyping platforms, arrays or SNP-calling approaches, resulting in use of different genome builds and allele definitions. Incorrect assumptions of identical allele definition among combined GWAS lead to a large portion of discarded genotypes or incorrect association findings. There is no published tool that predicts and converts among all major allele definitions. In this study, we have developed a tool, GACT, which stands for Genome build and Allele definition Conversion Tool, that predicts and inter-converts between any of the common SNP allele definitions and between the major genome builds. In addition, we assessed several factors that may affect imputation quality, and our results indicated that inclusion of singletons in the reference had detrimental effects while ambiguous SNPs had no measurable effect. Unexpectedly, exclusion of genotypes with missing rate > 0.001 (40% of study SNPs) showed no significant decrease of imputation quality (even significantly higher when compared to the imputation with singletons in the reference), especially for rare SNPs. GACT is a new, powerful, and user-friendly tool with both command-line and interactive online versions that can accurately predict, and convert between any of the common allele definitions and between genome builds for genome-wide meta-analysis and imputation of genotypes from SNP-arrays or deep
Moosazadeh, Mahmood; Nekoei-Moghadam, Mahmood; Aliram-Zany, Maryam; Amiresmaili, Mohammadreza
Glucose-6-phosphate dehydrogenase is one of the most common genetic deficiencies, which approximately 400 million people in the world suffer from. According to authors' initial search, numerous studies have been carried out in Iran regarding molecular variants of this enzyme. Thus, this meta-analysis presented a reliable estimation about prevalence of different types of molecular mutations of G6PD Enzyme in Iran. Keywords "glucose 6 phosphate dehydrogenase or G6PD, Mediterranean or Chatham or Cosenza and mutation, Iran or Iranian and their Persian equivalents" were searched in different databases. Moreover, reference list of the published studies were examined to increase sensitivity and to select more studies. After studying titles and abstracts of retrieved articles, excluding the repeated and unrelated ones, and evaluating quality of articles, documents were selected. Data was analyzed using STATA. After performing systematic review, 22 papers were entered this meta-analysis and 1698 subjects were examined concerning G6PD molecular mutation. In this meta-analysis, prevalence of Mediterranean mutation, Chatham mutation and Cosenza mutation in Iran was estimated 78.2%, 9.1% and 0.5% respectively. This meta-analysis showed that in spite of prevalence of different types of G6PD molecular mutations in center, north, north-west and west of Iran, the most common molecular mutations in people with G6PD deficiency in Iran, like other Mediterranean countries and countries around Persian Gulf, were Mediterranean mutation, Chatham mutation and Cosenza mutation. It is also recommended that future studies may focus on races and regions which haven't been taken into consideration up to now.
Zhang, Yi; Yang, Ye; Xie, Ming-Sheng; Ding, Xiang; Li, Hui; Liu, Zhi-Chen; Peng, Shi-Fang
A number of epidemiological studies have examined the effect of meat consumption on depression. However, no conclusion has been reached. The aim of this study was to examine the relationship between meat consumption and depression. The electronic databases of PUBMED and EMBASE were searched up to March 2017, for observational studies that examined the relationship between meat consumption and depression. The pooled odds ratio (OR) for the prevalence of depression and the relative risk (RR) for the incidence of depression, as well as their corresponding 95% confidence interval (CI), were calculated respectively (the highest versus the lowest category of meat consumption). A total of eight observational studies (three cross-sectional, three cohort and two case-control studies) were included in this meta-analysis. Specifically, six studies were related to the prevalence of depression, and the overall multi-variable adjusted OR suggested no significant association between meat consumption and the prevalence of depression (OR = 0.89, 95% CI: 0.65 to 1.22; P = 0.469). In contrast, for the three studies related to the incidence of depression, the overall multi-variable adjusted RR evidenced an association between meat consumption and a moderately higher incidence of depression (RR = 1.13, 95% CI: 1.03 to 1.24; P = 0.013). Meat consumption may be associated with a moderately higher risk of depression. However, it still warrants further studies to confirm such findings due to the limited number of prospective studies.
Hasson, Joseph; Limoni, Dana; Malcov, Mira; Frumkin, Tsvia; Amir, Hadar; Shavit, Tal; Bay, BjØrn; Many, Ariel; Almog, Benjamin
Preimplantation genetic diagnosis (PGD) may pose risks to pregnancy outcome owing to the invasiveness of the biopsy procedure. This study compares outcome of singleton and twin clinical pregnancies conceived after fresh embryo transfers of PGD (n = 89) and matched intracytoplasmic sperm injection (ICSI) pregnancies (n = 166). The study was carried out in a single university affiliated centre. Because of the paucity of available data, a literature-based meta-analysis of studies comparing neonatal outcome of PGD and ICSI pregnancies was also conducted. In the retrospective cohort study, obstetric and neonatal outcome were available in 67 PGD and 118 ICSI pregnancies. Perinatal outcomes were comparable between PGD and ICSI pregnancies. Meta-analysis revealed similar outcomes, except for higher rate of low birth weight (<2500 g) neonates in ICSI twin pregnancies (RR 0.86, 95% CI 0.74 to 1.0). Mean birth weight, gestational age at birth, pre-term deliveries (<37 weeks) and malformations were all comparable. In this cohort study and subsequent meta-analysis, no association was found between PGD conceived pregnancies and risks of adverse neonatal or obstetrical outcomes compared with ICSI pregnancies. Hence, blastomere biopsy for PGD does not seem to increase the risk for adverse perinatal outcome compared with ICSI pregnancies. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Bakbergenuly, Ilyas; Kulinskaya, Elena; Morgenthaler, Stephan
We study bias arising as a result of nonlinear transformations of random variables in random or mixed effects models and its effect on inference in group-level studies or in meta-analysis. The findings are illustrated on the example of overdispersed binomial distributions, where we demonstrate considerable biases arising from standard log-odds and arcsine transformations of the estimated probability p̂, both for single-group studies and in combining results from several groups or studies in meta-analysis. Our simulations confirm that these biases are linear in ρ, for small values of ρ, the intracluster correlation coefficient. These biases do not depend on the sample sizes or the number of studies K in a meta-analysis and result in abysmal coverage of the combined effect for large K. We also propose bias-correction for the arcsine transformation. Our simulations demonstrate that this bias-correction works well for small values of the intraclass correlation. The methods are applied to two examples of meta-analyses of prevalence. © 2016 The Authors. Biometrical Journal Published by Wiley-VCH Verlag GmbH & Co. KGaA.
Goldman, Samantha E.; Burke, Meghan M.
Although parent involvement is required by special education law and is important for all students, the literature synthesizing studies on parent involvement has focused on the general education parent population, often without addressing students with disabilities. The purpose of this review was to descriptively synthesize the literature on…
Noels, Eline C.; Lapid, Oren; Lindeman, Jan H. N.; Bastiaannet, Esther
The popularity of cosmetic breast augmentation and the incidence of breast cancer have been increasing worldwide. It has been hypothesized that the risk of breast cancer may be greater among patients who have undergone cosmetic breast implantation. The authors performed a meta-analysis of the
M.H.M. de Moor; P.T. Costa Jr; A. Terracciano; R.F. Krueger; E.J.C. de Geus (Eco); T. Toshiko; B.W.J.H. Penninx (Brenda); T. Esko; P.A.F. Madden (Pamela); J. Derringer; N. Amin (Najaf); G.A.H.M. Willemsen (Gonneke); J.J. Hottenga (Jouke Jan); M.A. Distel (Marijn); M. Uda (Manuela); S. Sanna (Serena); P. Spinhoven; C.A. Hartman; P.F. Sullivan (Patrick); A. Realo; J. Allik; A.C. Heath; M.L. Pergadia; P. Lin; R. Grucza; T. Nutile; M. Ciullo; D. Rujescu (Dan); I. Giegling (Ina); B. Konte; E. Widen (Elisabeth); D.L. Cousminer (Diana); J.G. Eriksson; A. Palotie; L. Peltonen; M. Luciano (Michelle); A. Tenesa (Albert); G. Davies; L.M. Lopez; N.K. Hansell (Narelle); S.E. Medland (Sarah Elizabeth); L. Ferrucci; D. Schlessinger; G.W. Montgomery; M.J. Wright (Margaret); Y.S. Aulchenko (Yurii); A.C.J.W. Janssens (Cécile); B.A. Oostra (Ben); A. Metspalu (Andres); I.J. Deary; K. Räikkönen (Katri); L.J. Bierut (Laura); N.G. Martin; C.M. van Duijn (Cornelia); D.I. Boomsma (Dorret); G.R. Abecasis (Gonçalo); A. Agrawal (Arpana)
textabstractPersonality can be thought of as a set of characteristics that influence people's thoughts, feelings and behavior across a variety of settings. Variation in personality is predictive of many outcomes in life, including mental health. Here we report on a meta-analysis of genome-wide
Lifshitz, Hefziba; Shtein, Sarit; Weiss, Izhak; Vakil, Eli
This meta-analysis combines the effect size (ES) of 40 explicit memory experiments in populations with intellectual disability (ID). Eight meta-analyses were performed, as well as contrast tests between ES. The explicit memory of participants with ID was inferior to that of participants with typical development (TD). Relatively preserved explicit…
Postmus, Iris; Warren, Helen R.; Trompet, Stella; Arsenault, Benoit J.; Avery, Christy L.; Bis, Joshua C.; Chasman, Daniel I.; de Keyser, Catherine E.; Deshmukh, Harshal A.; Evans, Daniel S.; Feng, QiPing; Li, Xiaohui; Smit, Roelof A. J.; Smith, Albert V.; Sun, Fangui; Taylor, Kent D.; Arnold, Alice M.; Barnes, Michael R.; Barratt, Bryan J.; Betteridge, John; Boekholdt, S. Matthijs; Boerwinkle, Eric; Buckley, Brendan M.; Chen, Y.-D. Ida; de Craen, Anton J. M.; Cummings, Steven R.; Denny, Joshua C.; Dubé, Marie Pierre; Durrington, Paul N.; Eiriksdottir, Gudny; Ford, Ian; Guo, Xiuqing; Harris, Tamara B.; Heckbert, Susan R.; Hofman, Albert; Hovingh, G. Kees; Kastelein, John J. P.; Launer, Leonore J.; Liu, Ching-Ti; Liu, Yongmei; Lumley, Thomas; McKeigue, Paul M.; Munroe, Patricia B.; Neil, Andrew; Nickerson, Deborah A.; Nyberg, Fredrik; O'Brien, Eoin; O'Donnell, Christopher J.; Post, Wendy; Poulter, Neil; Vasan, Ramachandran S.; Rice, Kenneth; Rich, Stephen S.; Rivadeneira, Fernando; Sattar, Naveed; Sever, Peter; Shaw-Hawkins, Sue; Shields, Denis C.; Slagboom, P. Eline; Smith, Nicholas L.; Smith, Joshua D.; Sotoodehnia, Nona; Stanton, Alice; Stott, David J.; Stricker, Bruno H.; Stürmer, Til; Uitterlinden, André G.; Wei, Wei-Qi; Westendorp, Rudi G. J.; Whitsel, Eric A.; Wiggins, Kerri L.; Wilke, Russell A.; Ballantyne, Christie M.; Colhoun, Helen M.; Cupples, L. Adrienne; Franco, Oscar H.; Gudnason, Vilmundur; Hitman, Graham; Palmer, Colin N. A.; Psaty, Bruce M.; Ridker, Paul M.; Stafford, Jeanette M.; Stein, Charles M.; Tardif, Jean-Claude; Caulfield, Mark J.; Jukema, J. Wouter; Rotter, Jerome I.; Krauss, Ronald M.
In addition to lowering low density lipoprotein cholesterol (LDL-C), statin therapy also raises high density lipoprotein cholesterol (HDL-C) levels. Inter-individual variation in HDL-C response to statins may be partially explained by genetic variation. We performed a meta-analysis of genome-wide
Springelkamp, Henriët; Mishra, Aniket; Hysi, Pirro G.; Gharahkhani, Puya; Höhn, René; Khor, Chiea-Chuen; Cooke Bailey, Jessica N.; Luo, Xiaoyan; Ramdas, Wishal D.; Vithana, Eranga; Koh, Victor; Yazar, Seyhan; Xu, Liang; Forward, Hannah; Kearns, Lisa S.
Primary open-angle glaucoma is the most common optic neuropathy and an important cause of irreversible blindness worldwide. The optic nerve head or optic disc is divided in two parts: a central cup (without nerve fibers) surrounded by the neuroretinal rim (containing axons of the retinal ganglion cells). The International Glaucoma Genetics Consortium conducted a meta-analysis of genome-wide association studies consisting of 17,248 individuals of European ancestry and 6,841 individuals of Asia...
Lavigne, Eric; Holowaty, Eric J; Pan, Sai Yi; Villeneuve, Paul J; Johnson, Kenneth C; Fergusson, Dean A; Morrison, Howard; Brisson, Jacques
To evaluate whether the stage distribution among women diagnosed as having breast cancer differs between those who have received breast implants for cosmetic purposes and those with no implants and to evaluate whether cosmetic breast augmentation before the detection of breast cancer is a predictor of post-diagnosis survival. Systematic review of observational studies with two meta-analyses. Systematic search of the literature published before September 2012 conducted in Medline, Embase, Global health, CINAHL, IPAB, and PsycINFO. Eligible publications were those that included women diagnosed as having breast cancer and who had had augmentation mammaplasty for cosmetic purposes. The overall odds ratio of the first meta-analysis based on 12 studies was 1.26 (95% confidence interval 0.99 to 1.60; P=0.058; I(2)=35.6%) for a non-localized stage of breast cancer at diagnosis comparing women with implants who had breast cancer and women without implants who had breast cancer. The second meta-analysis, based on five studies, evaluated the relation between cosmetic breast implantation and survival. This meta-analysis showed reduced survival after breast cancer among women who had implants compared with those who did not (overall hazard ratio for breast cancer specific mortality 1.38, 95% confidence interval 1.08 to 1.75). The research published to date suggests that cosmetic breast augmentation adversely affects the survival of women who are subsequently diagnosed as having breast cancer. These findings should be interpreted with caution, as some studies included in the meta-analysis on survival did not adjust for potential confounders. Further investigations are warranted regarding diagnosis and prognosis of breast cancer among women with breast implants.
Dunst, Carl J.; Trivette, Carol M.; Hamby, Deborah W.
Incorporating the interests and preferences of young children with autism spectrum disorders into interventions to promote prosocial behavior and decrease behavior excesses has emerged as a promising practice for addressing the core features of autism. The efficacy of interest-based early intervention practices was examined in a meta-analysis of 24 studies including 78 children 2 to 6 years of age diagnosed with autism spectrum disorders. Effect size analyses of intervention versus noninterve...
C.E. Elks (Cathy); J.R.B. Perry (John); P. Sulem (Patrick); D.I. Chasman (Daniel); N. Franceschini (Nora); C. He (Chunyan); K.L. Lunetta (Kathryn); J.A. Visser (Jenny); E.M. Byrne (Enda); D.L. Cousminer (Diana); D.F. Gudbjartsson (Daniel); T. Esko (Tõnu); B. Feenstra (Bjarke); J.J. Hottenga (Jouke Jan); D.L. Koller (Daniel); Z. Kutalik (Zoltán); P. Lin (Peng); M. Mangino (Massimo); M. Marongiu (Mara); P.F. McArdle (Patrick); A.V. Smith (Albert Vernon); L. Stolk (Lisette); S. van Wingerden (Sophie); J.H. Zhao (Jing Hua); E. Albrecht (Eva); T. Corre (Tanguy); E. Ingelsson (Erik); C. Hayward (Caroline); P.K. Magnusson (Patrik); S. Ulivi (Shelia); N.M. Warrington (Nicole); L. Zgaga (Lina); H. Alavere (Helene); N. Amin (Najaf); T. Aspelund (Thor); S. Bandinelli (Stefania); I.E. Barroso (Inês); G. Berenson (Gerald); S.M. Bergmann (Sven); H. Blackburn (Hannah); E.A. Boerwinkle (Eric); J.E. Buring (Julie); F. Busonero; H. Campbell (Harry); S.J. Chanock (Stephen); W. Chen (Wei); M. Cornelis (Marilyn); D.J. Couper (David); A.D. Coviello (Andrea); P. d' Adamo (Pio); U. de Faire (Ulf); E.J.C. de Geus (Eco); P. Deloukas (Panagiotis); A. Döring (Angela); D.F. Easton (Douglas); G. Eiriksdottir (Gudny); V. Emilsson (Valur); J.G. Eriksson (Johan); L. Ferrucci (Luigi); A.R. Folsom (Aaron); T. Foroud (Tatiana); M. Garcia (Melissa); P. Gasparini (Paolo); F. Geller (Frank); C. Gieger (Christian); V. Gudnason (Vilmundur); A.S. Hall (Alistair); S.E. Hankinson (Susan); L. Ferreli (Liana); A.C. Heath (Andrew); D.G. Hernandez (Dena); A. Hofman (Albert); F.B. Hu (Frank); T. Illig (Thomas); M.R. Järvelin; A.D. Johnson (Andrew); D. Karasik (David); K-T. Khaw (Kay-Tee); D.P. Kiel (Douglas); T.O. Kilpelänen (Tuomas); I. Kolcic (Ivana); P. Kraft (Peter); L.J. Launer (Lenore); J.S.E. Laven (Joop); S. Li (Shengxu); J. Liu (Jianjun); D. Levy (Daniel); N.G. Martin (Nicholas); M. Melbye (Mads); V. Mooser (Vincent); J.C. Murray (Jeffrey); M.A. Nalls (Michael); P. Navarro (Pau); M. Nelis (Mari); A.R. Ness (Andrew); K. Northstone (Kate); B.A. Oostra (Ben); M. Peacock (Munro); C. Palmer (Cameron); A. Palotie (Aarno); G. Paré (Guillaume); A.N. Parker (Alex); N.L. Pedersen (Nancy); L. Peltonen (Leena Johanna); C.E. Pennell (Craig); P.D.P. Pharoah (Paul); O. Polasek (Ozren); A.S. Plump (Andrew); A. Pouta (Anneli); E. Porcu (Eleonora); T. Rafnar (Thorunn); J.P. Rice (John); S.M. Ring (Susan); F. Rivadeneira Ramirez (Fernando); I. Rudan (Igor); C. Sala (Cinzia); V. Salomaa (Veikko); S. Sanna (Serena); D. Schlessinger; N.J. Schork (Nicholas); A. Scuteri (Angelo); A.V. Segrè (Ayellet); A.R. Shuldiner (Alan); N. Soranzo (Nicole); U. Sovio (Ulla); S.R. Srinivasan (Sathanur); D.P. Strachan (David); M.L. Tammesoo; E. Tikkanen (Emmi); D. Toniolo (Daniela); K. Tsui (Kim); L. Tryggvadottir (Laufey); J.P. Tyrer (Jonathan); M. Uda (Manuela); R.M. van Dam (Rob); J.B.J. van Meurs (Joyce); P. Vollenweider (Peter); G. Waeber (Gérard); N.J. Wareham (Nick); D. Waterworth (Dawn); H.E. Wichmann (Heinz Erich); G.A.H.M. Willemsen (Gonneke); J.F. Wilson (James); A.F. Wright (Alan); L. Young (Lauren); G. Zhai (Guangju); W.V. Zhuang; L.J. Bierut (Laura); D.I. Boomsma (Dorret); H.A. Boyd (Heather); L. Crisponi (Laura); E.W. Demerath (Ellen); P. Tikka-Kleemola (Päivi); M.J. Econs (Michael); T.B. Harris (Tamara); D. Hunter (David); R.J.F. Loos (Ruth); A. Metspalu (Andres); G.W. Montgomery (Grant); P.M. Ridker (Paul); T.D. Spector (Tim); E.A. Streeten (Elizabeth); K. Stefansson (Kari); U. Thorsteinsdottir (Unnur); A.G. Uitterlinden (André); E. Widen (Elisabeth); J. Murabito (Joanne); K. Ong (Ken); M.N. Weedon (Michael)
textabstractTo identify loci for age at menarche, we performed a meta-analysis of 32 genome-wide association studies in 87,802 women of European descent, with replication in up to 14,731 women. In addition to the known loci at LIN28B (P = 5.4 × 10 -60) and 9q31.2 (P = 2.2 × 10 -33), we identified 30
Koppes, L.L.J.; Dekker, J.M.; Hendriks, H.F.J.; Bouter, L.M.; Heine, R.J.
OBJECTIVE - This meta-analysis was undertaken to obtain insight regarding the shape and strength of the relationship between alcohol consumption and the risk of type 2 diabetes, the effects of adjustment for confounders, and the effect of modification by type 2 diabetes definition, sex, and BMI. RESEARCH DESIGN AND METHODS - The 15 original prospective cohort studies that were included comprise 11,959 incident cases of type 2 diabetes in 369,862 individuals who, on average, were followed for ...
Duan, Liang; Hu, Xuefei; Jin, Yuxing; Liu, Ruijun; You, Qingjun
Surviving expression might serve as a prognostic biomarker predicting the clinical outcome of non-small cell lung cancer (NSCLC). The study was conducted to explore the potential correlation of survivin protein expression with NSCLC and its clinicopathologic characteristics. PubMed, Medline, Cochrane Library, CNKI and Wanfang database were searched through January 2016 with a set of inclusion and exclusion criteria. Data was extracted from these articles and all statistical analysis was conducted by using Stata 12.0. A total of 28 literatures (14 studies in Chinese and 14 studies in English) were enrolled in this meta-analysis, including 3206 NSCLC patients and 816 normal controls. The result of meta-analysis demonstrated a significant difference of survivin positive expression between NSCLC patients and normal controls (RR = 7.16, 95 % CI = 4.63-11.07, P < 0.001). To investigate the relationship of survivin expression and clinicopathologic characteristics, we performed a meta-analysis in NSCLC patients. Our results indicates survivin expression was associated with histological differentiation, tumor-node-metastasis (TNM) stage and lymph node metastasis (LNM) (RR = 0.80, 95 % CI = 0.73-0.87, P < 0.001; RR = 0.75, 95 % CI = 0.67-0.84, P < 0.001; RR = 1.14, 95 % CI = 1.01-1.29, P = 0.035, respectively), but not pathological type and tumor size. (RR = 1.00, 95 % CI = 0.93-1.07, P = 0.983; RR = 0.95, 95 % CI = 0.86-1.05, P = 0.336, respectively). Higher expression of survivin in NSCLC patients was found when compared to normal controls. Survivin expression was associated with the clinicopathologic characteristics of NSCLC and may serves as an important biomarker for NSCLC progression
Xu, Chen; Lu, Hong-Xiang; Wang, Yu-Xiao; Chen, Yu; Yang, Sheng-Hong; Luo, Yong-Jun
People rapidly ascending to high altitudes (>2500 m) may suffer from acute mountain sickness (AMS). The association between smoking and AMS risk remains unclear. Therefore, we performed a meta-analysis to evaluate the association between smoking and AMS risk. The association between smoking and AMS risk was determined according to predefined criteria established by our team. Meta-analysis was conducted according to the PRISMA guidelines. We included all relevant studies listed in the PubMed and Embase databases as of September 2015 in this meta-analysis and performed systemic searches using the terms "smoking", "acute mountain sickness" and "risk factor". The included studies were required to provide clear explanations regarding their definitions of smoking, the final altitudes reached by their participants and the diagnostic criteria used to diagnose AMS. Odds ratios ( ORs ) were used to evaluate the association between smoking and AMS risk across the studies, and the Q statistic was used to test OR heterogeneity, which was considered significant when P smoking patients and 1986 non-smoking controls to analyze the association between smoking and AMS risk. We observed a significant association between AMS and smoking ( OR = 0.71, 95% CI 0.52-0.96, P = 0.03). We determined that smoking may protect against AMS development. However, we do not advise smoking to prevent AMS. More studies are necessary to confirm the role of smoking in AMS risk.
Song, Huihui; Yang, Lei; Jia, Chongqi
Mounting evidence suggests that maternal vitamin D status during pregnancy may be associated with development of childhood asthma, but the results are still inconsistent. A dose-response meta-analysis was performed to quantitatively summarize evidence on the association of maternal vitamin D status during pregnancy with the risk of childhood asthma. A systematic search was conducted to identify all studies assessing the association of maternal 25-hydroxyvitamin D (25(OH)D) during pregnancy with risk of childhood asthma. The fixed or random-effect model was selected based on the heterogeneity test among studies. Nonlinear dose-response relationship was assessed by restricted cubic spline model. Fifteen prospective studies with 12 758 participants and 1795 cases were included in the meta-analysis. The pooled relative risk of childhood asthma comparing the highest versus lowest category of maternal 25(OH)D levels was 0.87 (95% confidence interval, CI, 0.75-1.02). For dose-response analysis, evidence of a U-shaped relationship was found between maternal 25(OH)D levels and risk of childhood asthma (P nonlinearity = 0.02), with the lowest risk at approximately 70 nmol/L of 25(OH)D. This dose-response meta-analysis suggested a U-shaped relationship between maternal blood 25(OH)D levels and risk of childhood asthma. Further studies are needed to confirm the association. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Shim, Sungryul; Kim, Jiyoung; Jung, Wonguen; Shin, In-Soo; Bae, Jong-Myon
This review aimed to arrange the process of a systematic review of genome-wide association studies in order to practice and apply a genome-wide meta-analysis (GWMA). The process has a series of five steps: searching and selection, extraction of related information, evaluation of validity, meta-analysis by type of genetic model, and evaluation of heterogeneity. In contrast to intervention meta-analyses, GWMA has to evaluate the Hardy-Weinberg equilibrium (HWE) in the third step and conduct meta-analyses by five potential genetic models, including dominant, recessive, homozygote contrast, heterozygote contrast, and allelic contrast in the fourth step. The 'genhwcci' and 'metan' commands of STATA software evaluate the HWE and calculate a summary effect size, respectively. A meta-regression using the 'metareg' command of STATA should be conducted to evaluate related factors of heterogeneities.
Full Text Available This review aimed to arrange the process of a systematic review of genome-wide association studies in order to practice and apply a genome-wide meta-analysis (GWMA. The process has a series of five steps: searching and selection, extraction of related information, evaluation of validity, meta-analysis by type of genetic model, and evaluation of heterogeneity. In contrast to intervention meta-analyses, GWMA has to evaluate the Hardy–Weinberg equilibrium (HWE in the third step and conduct meta-analyses by five potential genetic models, including dominant, recessive, homozygote contrast, heterozygote contrast, and allelic contrast in the fourth step. The ‘genhwcci’ and ‘metan’ commands of STATA software evaluate the HWE and calculate a summary effect size, respectively. A meta-regression using the ‘metareg’ command of STATA should be conducted to evaluate related factors of heterogeneities.
Lima, Estelita Pereira; Goulart, Marília Oliveira Fonseca; Rolim Neto, Modesto Leite
Aedes aegypti is a vector of international concern because it can transmit to humans three important arboviral diseases: yellow fever, dengue and chikungunya. Epidemics that are repeated year after year in a variety of urban centers indicate that there are control failures, allowing the vector to continue expanding. To identify the most effective vector control strategies and the factors that contributed to the success or failure of each strategy, we carried out a systematic review with meta-analysis of articles published in 12 databases, from 1974 to the month of December 2013. We evaluated the association between the use of whatever chemical substance, mechanical agent, biological or integrated actions against A. aegypti and the control of the vector, as measured by 10 indicators. We found 2,791 articles, but after careful selection, only 26 studies remained for analysis related to control interventions implemented in 15 countries, with 5 biological, 5 chemical, 3 mechanical and 13 integrated strategies. The comparison among all of them, indicated that the control of A. aegypti is significantly associated with the type of strategy used, and that integrated interventions consist of the most effective method for controlling A. aegypti. The most effective control method was the integrated approach, considering the influence of eco-bio-social determinants in the virus-vector-man epidemiological chain, and community involvement, starting with community empowerment as active agents of vector control.
Sulloway, Frank J; Zweigenhaft, Richard L
According to expectations derived from evolutionary theory, younger siblings are more likely than older siblings to participate in high-risk activities. The authors test this hypothesis by conducting a meta-analysis of 24 previous studies involving birth order and participation in dangerous sports. The odds of laterborns engaging in such activities were 1.48 times greater than for firstborns (N = 8,340). The authors also analyze performance data on 700 brothers who played major league baseball. Consistent with their greater expected propensity for risk taking, younger brothers were 10.6 times more likely to attempt the high-risk activity of base stealing and 3.2 times more likely to steal bases successfully (odds ratios). In addition, younger brothers were significantly superior to older brothers in overall batting success, including two measures associated with risk taking. As expected, significant heterogeneity among various performance measures for major league baseball players indicated that older and younger brothers excelled in different aspects of the game.
Morgan, Eileen; Halliday, Sophia R; Campbell, Gemma R; Cardwell, Chris R; Patterson, Chris C
The aim of this study was to investigate the association between routine vaccinations and the risk of childhood type 1 diabetes mellitus by systematically reviewing the published literature and performing meta-analyses where possible. A comprehensive literature search was performed of MEDLINE and EMBASE to identify all studies that compared vaccination rates in children who subsequently developed type 1 diabetes mellitus and in control children. ORs and 95% CIs were obtained from published reports or derived from individual patient data and then combined using a random effects meta-analysis. In total, 23 studies investigating 16 vaccinations met the inclusion criteria. Eleven of these contributed to meta-analyses which included data from between 359 and 11,828 childhood diabetes cases. Overall, there was no evidence to suggest an association between any of the childhood vaccinations investigated and type 1 diabetes mellitus. The pooled ORs ranged from 0.58 (95% CI 0.24, 1.40) for the measles, mumps and rubella (MMR) vaccination in five studies up to 1.04 (95% CI 0.94, 1.14) for the haemophilus influenza B (HiB) vaccination in 11 studies. Significant heterogeneity was present in most of the pooled analyses, but was markedly reduced when analyses were restricted to study reports with high methodology quality scores. Neither this restriction by quality nor the original authors' adjustments for potential confounding made a substantial difference to the pooled ORs. This study provides no evidence of an association between routine vaccinations and childhood type 1 diabetes.
Adamu, Mariam Abdullahi; Weck, Melanie Nicole; Gao, Lei; Brenner, Hermann
Chronic atrophic gastritis (CAG) is an important precursor lesion of intestinal gastric cancer. As it is typically asymptomatic, epidemiological data on the incidence of CAG are sparse. We aimed to provide an overview of published data on CAG incidence (overall and according to risk factors) from follow-up studies. Articles with information on incidence of CAG published in English until 26th of July 2009 were identified through a systematic MEDLINE and EMBASE search. Data extracted include study characteristics and key findings regarding the incidence of CAG. A meta-analysis was performed on the association between Helicobacter pylori infection and CAG incidence. Overall, data on CAG incidence were available from 14 studies, in 7 studies incidence could be estimated according to H. pylori infection. Most studies were conducted in symptomatic or high risk populations and the maximum number of incident cases was 284. Incidence estimates ranged from 0 to 11% per year and were consistently below 1% in patients not infected with H. pylori. The highest incidence was observed in a special study conducted on ulcer patients treated by proximal gastric vagotomy. Rate ratios for the association between H. pylori infection and CAG incidence ranged from 2.4 to 7.6 with a summary estimate of 5.0 (95% confidence interval: 3.1-8.3). Incidence of CAG is very low in the absence of H. pylori infection. There is a need for more population-based studies to provide comparable estimates of incidence and the impact of risk factors in the development of CAG.
Full Text Available AbstractBackground and Objective: Many clinical researches have been carried out to investigate the relationship between myocardial infarction (MI and periodontitis. Despite most of them indicated that the periodontitis may be associated with an increased risk of MI, the findings and study types of these studies have been inconsistent. The goal of this meta-analysis was to critically assess the strength of the association between MI and periodontitis in case-control studies.Methods: PubMed and the Cochrane Library were searched for eligible case-control studies reporting relevant parameters that compared periodontal status between MI and control subjects. The odds ratios (ORs and 95% confidence intervals (CIs from each study were pooled to estimate the strength of the association between MI and periodontitis. The mean differences and 95% CIs for periodontal-related parameters were calculated to determine their overall effects.Results: Seventeen studies including a total of 3456 MI patients and 3875 non-MI control subjects were included. The pooled OR for the association between MI and periodontitis was 2.531 (95% CI: 1.927-3.324. The mean differences (95% CIs for clinical attachment loss, probing depth, bleeding on probing, plaque index, and the number of missing teeth were 1.000 (0.726-1.247, 1.209 (0.538-1.880, 0.342 (0.129-0.555, 0.383 (0.205-0.560, and 4.122 (2.012-6.232, respectively. Conclusion: With the current evidence, the results support the presence of a significant association between MI and periodontitis. Moreover, MI patients had worse periodontal and oral hygiene status and fewer teeth than did control subjects. More high-quality and well-designed studies focusing on the casual relationship between MI and periodontitis should be conducted in the future.
Hauser, Robert A; Abler, Victor; Eyal, Eli; Eliaz, Rom E
To evaluate the efficacy of rasagiline versus placebo in a pooled population of patients with early Parkinson's disease (PD). TEMPO and ADAGIO were Phase III studies that evaluated the symptomatic efficacy of rasagiline versus placebo in patients with early PD. This meta-analysis included Unified Parkinson's Disease Rating Scale (UPDRS) observations from weeks 12, 24 and 36 in ADAGIO and from weeks 14 and 26 in TEMPO; TEMPO visits were recoded to weeks 12 and 24, respectively. The present analysis includes all patients who received rasagiline 1 mg/day, 2 mg/day or placebo, and had ≥1 post-baseline observations and a subgroup of patients whose baseline UPDRS Total scores were ≥27 (Upper Quartile population). Change from baseline in UPDRS scores were evaluated using mixed models repeated measures analyses. Of the 1578 patients randomized to the two studies, 1546 patients met criteria for inclusion in the meta-analysis. Effects on UPDRS Total, motor and activities of daily living scores were significantly better for both doses of rasagiline compared with placebo at all time periods. The Upper Quartile population included 402 patients with a UPDRS Total score ≥27 at baseline. These patients generally demonstrated a larger magnitude of treatment effect than was seen in the full population. This meta-analysis confirms the efficacy of rasagiline monotherapy over 36 weeks. Although TEMPO and ADAGIO are considered studies of "very early" PD, both contained a sizeable pool of patients with more severe disease. In addition, the meta-analysis showed a larger magnitude of effect in patients with more severe baseline disease.
Ramezani, Mazaher; Sadeghi, Masoud
Human papillomaviruses (HPVs) are a large and ubiquitous group of viruses that some of them have been suggested as a co-factor in the development of non-melanoma skin cancers. The aim of this meta-analysis study was to evaluate HPVs' prevalence in basal cell carcinoma (BCC) of the skin and the risk of them in the BCC patients compared with the healthy controls. Five databases were searched from January 1980 to February 2017. A random-effects meta-analysis was done with the event rate (ER) for the prevalence of HPVs and odds ratio (OR) for estimation of the incidence of HPVs. Out of 1087 studies, 45 studies were included in the review. The pooled analysis demonstrated that the incidence of γ-HPV was effective in the BCC patients compared with the healthy controls [OR = 1.97; 95% CI: 1.52-2.55; p 0.05). The pooled ER of incidence of β1-HPV in the BCC patients was z3.3% and for β2-HPV in BCC patients was 44.2%. In conclusion, this meta-analysis showed that probably the risk of γ-HPV was more on BCC patients and also the rate of γ-HPV was higher than α-, β- and EV-HPVs in the BCC patients.
Full Text Available Background. Univariate meta-analysis (UM procedure, as a technique that provides a single overall result, has become increasingly popular. Neglecting the existence of other concomitant covariates in the models leads to loss of treatment efficiency. Our aim was proposing four new approximation approaches for the covariance matrix of the coefficients, which is not readily available for the multivariate generalized least square (MGLS method as a multivariate meta-analysis approach. Methods. We evaluated the efficiency of four new approaches including zero correlation (ZC, common correlation (CC, estimated correlation (EC, and multivariate multilevel correlation (MMC on the estimation bias, mean square error (MSE, and 95% probability coverage of the confidence interval (CI in the synthesis of Cox proportional hazard models coefficients in a simulation study. Result. Comparing the results of the simulation study on the MSE, bias, and CI of the estimated coefficients indicated that MMC approach was the most accurate procedure compared to EC, CC, and ZC procedures. The precision ranking of the four approaches according to all above settings was MMC ≥ EC ≥ CC ≥ ZC. Conclusion. This study highlights advantages of MGLS meta-analysis on UM approach. The results suggested the use of MMC procedure to overcome the lack of information for having a complete covariance matrix of the coefficients.
Dehesh, Tania; Zare, Najaf; Ayatollahi, Seyyed Mohammad Taghi
Univariate meta-analysis (UM) procedure, as a technique that provides a single overall result, has become increasingly popular. Neglecting the existence of other concomitant covariates in the models leads to loss of treatment efficiency. Our aim was proposing four new approximation approaches for the covariance matrix of the coefficients, which is not readily available for the multivariate generalized least square (MGLS) method as a multivariate meta-analysis approach. We evaluated the efficiency of four new approaches including zero correlation (ZC), common correlation (CC), estimated correlation (EC), and multivariate multilevel correlation (MMC) on the estimation bias, mean square error (MSE), and 95% probability coverage of the confidence interval (CI) in the synthesis of Cox proportional hazard models coefficients in a simulation study. Comparing the results of the simulation study on the MSE, bias, and CI of the estimated coefficients indicated that MMC approach was the most accurate procedure compared to EC, CC, and ZC procedures. The precision ranking of the four approaches according to all above settings was MMC ≥ EC ≥ CC ≥ ZC. This study highlights advantages of MGLS meta-analysis on UM approach. The results suggested the use of MMC procedure to overcome the lack of information for having a complete covariance matrix of the coefficients.
Ben, Qiwen; Zhong, Jie; Liu, Jun; Wang, Lifu; Sun, Yunwei; Yv, Lifen; Yuan, Yaozong
There have been contradictory results about the association of fruits and vegetables intake with colorectal adenoma (CRA) risk, the precursor lesion of colorectal cancer. Herein, we have conducted a meta-analysis of the published observational studies to have a clear understanding about this association.Eligible studies up to November 30, 2014, were identified and retrieved by searching MEDLINE and EMBASE databases along with the manual review of the reference list of the retrieved studies. The quality of the included studies was evaluated using Newcastle-Ottawa Quality Assessment Scale, and random-effects model was used to calculate summary relative risk (SRR) and corresponding 95% confidence interval (CI).A total of 22 studies involving 11,696 CRA subjects were part of this meta-analysis. The SRR for the highest versus the lowest intake of vegetables alone was 0.91 (95% CI: 0.80-1.02, Pheterogeneity = 0.025), whereas for vegetables and fruits combined, it was 0.82 (95% CI: 0.75-0.91, Pheterogeneity = 0.369), and for fruits alone, it was 0.79 (95% CI: 0.71-0.88, Pheterogeneity = 0.111). In addition, linear dose-response analysis also showed similar results, for example, for per 100 g/d increment of fruits, the SRR was 0.94 (95% CI: 0.92-0.97) and for vegetables it was 0.98 (95% CI: 0.96-1.01). Nonlinear association was only observed for vegetables (Pnonlinearity = 0.024), but not for fruits (Pnonlinearity = 0.583).Thus, this meta-analysis suggested that fruits consumption have a significant protective effect on CRA risk, but not vegetables. Moreover, we recommend additional studies with prospective designs that use validated questionnaires and control for important confounders to further validate the overall results.
Sui, Hua; Sun, Nijing; Zhan, Libin; Lu, Xiaoguang; Chen, Tuo; Mao, Xinyong
The prevalence of type 2 diabetes is increasing rapidly around the world. Work-related stress is thought to be a major risk factor for type 2 diabetes; however, this association has not been widely studied, and the findings that have been reported are inconsistent. Therefore, we conducted a meta-analysis of prospective cohort studies to explore the association between work-related stress and risk for type 2 diabetes. A systematic literature search and manual search limited to articles published in English were performed to select the prospective cohort studies evaluated the association between work-related stress and risk for type 2 diabetes up to September 2014 from four electronic databases including PubMed, EMBASE, the Cochrane Library and Web of Science. A random-effects model was used to estimate the overall risk. No significant association was found between work-related stress and risk for type 2 diabetes based on meta-analysis of seven prospective cohort studies involving 214,086 participants and 5,511 cases (job demands: relative risk 0.94 [95% confidence interval 0.72-1.23]; decision latitude: relative risk 1.16 [0.85-1.58]; job strain: relative risk 1.12 [.0.95-1.32]). However, an association between work-related stress and risk for type 2 diabetes was observed in women (job strain: relative risk 1.22 [1.01-1.46]) (P = 0.04). A sensitivity analysis conducted by excluding one study in each turn yielded similar results. No publication bias was detected with a funnel plot despite the limited number of studies included in the analysis. The results of this meta-analysis did not confirm a direct association between work-related stress and risk for type 2 diabetes. In subgroup analyses we found job strain was a risk factor for type 2 diabetes in women.
Full Text Available Aims. Published data on the associations of VEGF polymorphisms with diabetic retinopathy (DR susceptibility are inconclusive. A systematic meta-analysis was undertaken to clarify this topic. Methods. Data were collected from the following electronic databases: PubMed, Embase, OVID, Web of Science, Elsevier Science Direct, Excerpta Medica Database (EMBASE, and Cochrane Library with the last report up to January 10, 2014. ORs and 95% CIs were calculated for VEGF–2578C/A (rs699947, –1154G/A (rs1570360, –460T/C (rs833061, −634G>C (rs2010963, and +936C/T (rs3025039 in at least two published studies. Meta-analysis was performed in a fixed/random effect model by using the software STATA 12.0. Results. A total of 11 studies fulfilling the inclusion criteria were included in this meta-analysis. A significant relationship between VEGF+936C/T (rs3025039 polymorphism and DR was found in a recessive model (OR = 3.19, 95% CI = 1.20–8.41, and P(z=0.01 in Asian and overall populations, while a significant association was also found between –460T/C (rs833061 polymorphism and DR risk under a recessive model (OR = 2.12, 95% CI = 1.12–4.01, and P(z=0.02. Conclusions. Our meta-analysis demonstrates that +936C/T (rs3025039 is likely to be associated with susceptibility to DR in Asian populations, and the recessive model of –460T/C (rs833061 is associated with elevated DR susceptibility.
Margaritella, Nicolò; Mendozzi, Laura; Garegnani, Massimo; Gilardi, Elisabetta; Nemni, Raffaello; Pugnetti, Luigi
The usefulness of sympathetic skin responses (SSR) in multiple sclerosis (MS) has been advocated by several studies in the last 20 years; however, due to a great heterogeneity of findings, a comprehensive meta-analysis of case-control studies is in order to pinpoint consistencies and investigate the causes of discrepancies. We searched MEDLINE, EMBASE and Cochrane databases for case-control studies comparing SSR absence frequency and latency between patients with MS and healthy controls. Thirteen eligible studies including 415 MS patients and 331 healthy controls were identified. The pooled analysis showed that SSR can be always obtained in healthy controls while 34% of patients had absent SSRs in at least one limb (95% CI 22-47%; p studies (I 2 = 90.3%). Patients' age explained 22% of the overall variability and positive correlations were found with Expanded Disability Status Scale and disease duration. The pooled mean difference of SSR latency showed a significant increase in patients on both upper (193 ms; 95% CI 120-270 ms) and lower (350 ms; 95% CI 190-510 ms) extremities. We tested the discriminatory value of SSR latency thresholds defined as the 95% confidence interval (CI) upper bound of the healthy controls, and validated the results on a new dataset. The lower limb threshold of 1.964 s produces the best results in terms of sensitivity 0.86, specificity 0.67, positive predicted value 0.75 and negative predicted value 0.80. Despite a considerable heterogeneity of findings, there is evidence that SSR is a useful tool in MS.
Hao, Yongqiang; Li, Huiwu; Tang, Tingting; Wang, Hao; Yan, Weili; Dai, Kerong
Background Prospective studies that have examined the association between dietary magnesium intake and serum magnesium concentrations and the risk of cardiovascular disease (CVD) events have reported conflicting findings. We undertook a meta-analysis to evaluate the association between dietary magnesium intake and serum magnesium concentrations and the risk of total CVD events. Methodology/Principal Findings We performed systematic searches on MEDLINE, EMBASE, and OVID up to February 1, 2012 without limits. Categorical, linear, and nonlinear, dose-response, heterogeneity, publication bias, subgroup, and meta-regression analysis were performed. The analysis included 532,979 participants from 19 studies (11 studies on dietary magnesium intake, 6 studies on serum magnesium concentrations, and 2 studies on both) with 19,926 CVD events. The pooled relative risks of total CVD events for the highest vs. lowest category of dietary magnesium intake and serum magnesium concentrations were 0.85 (95% confidence interval 0.78 to 0.92) and 0.77 (0.66 to 0.87), respectively. In linear dose-response analysis, only serum magnesium concentrations ranging from 1.44 to 1.8 mEq/L were significantly associated with total CVD events risk (0.91, 0.85 to 0.97) per 0.1 mEq/L (Pnonlinearity = 0.465). However, significant inverse associations emerged in nonlinear models for dietary magnesium intake (Pnonlinearity = 0.024). The greatest risk reduction occurred when intake increased from 150 to 400 mg/d. There was no evidence of publication bias. Conclusions/Significance There is a statistically significant nonlinear inverse association between dietary magnesium intake and total CVD events risk. Serum magnesium concentrations are linearly and inversely associated with the risk of total CVD events. PMID:23520480
Hu, Jiande; Dong, Yonghai; Chen, Xiaodan; Liu, Yun; Ma, Dongyang; Liu, Xiaoyun; Zheng, Ruizhi; Mao, Xiangqun; Chen, Ting; He, Wei
According to World Health Organization, for every committed suicide there were 20 suicide attempts at least. In the last decade, despite the increasing awareness on suicide attempts among adolescents in China, there has been no comprehensive system reporting vital statistics. Consequently, the prevalence of suicide attempts reported in some studies ranged variedly. Therefore, the purpose of this study was to provide the first meta-analysis of cross-sectional studies of suicide attempts to fill this gap. Two reviewers independently screened potentially relevant cross-sectional studies of suicide attempts through PubMed-Medline, Embase, Wanfang Data, Chongqing VIP and Chinese National Knowledge Infrastructure databases using the core terms 'suicid*'/'suicide attempt*'/'attempted suicide' and 'adolescen*'/'youth'/'child*'/'student*' and 'China'/'Chinese' in the article titles, abstracts and keywords. Chi-square based Q test and I(2) statistic assessed the heterogeneity. Forest plot was used to display results graphically. Potential publication bias was assessed by the funnel plot, Begg's and Egger's test. In total, 43 studies with 200,124 participants met the eligibility criteria. The pooled prevalence of suicide attempts among Chinese adolescents was 2.94% (95% CI: 2.53%-3.41%). Substantial heterogeneity in prevalence estimates was revealed. Subgroup analyses showed that the prevalence for males was 2.50% (95% CI: 2.08%-3.01%), and for females was 3.17% (95% CI: 2.56%-3.91%). In sum, abstracting across the literatures, the prevalence of suicide attempts among Chinese adolescents was moderate compared with other countries around the world. Necessary measures should be set out prevent them in the future. Copyright © 2015 Elsevier Inc. All rights reserved.
Full Text Available Leila Jouybari,1 Marzieh Saei Ghare Naz,2 Akram Sanagoo,1 Faezeh Kiani,3 Fatemeh Sayehmiri,4 Kourosh Sayehmiri,5 Ali Hasanpour Dehkordi6 1Nursing Research Center, Goletsan University of Medical Sciences, Gorgan, Iran; 2Student Research Committee, School of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 3Student Research Committee, Ilam University of Medical Sciences, Ilam, Iran; 4Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 5Department of Social Medicine, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran; 6Department of Medical Surgical, Nursing and Midwifery, Shahrekord University of Medical Sciences, Shahrekord, Iran Aims and background: Breast cancer (BC is responsible for a large proportion of incidence of cancer in the world. Identifying the risk factors contributing to the incidence of BC is crucial to find efficient preventive and management strategies for this disease. Several studies have examined Arsenic (As, Cadmium (Cd, and Nickel (Ni as risk factors for BC. The present study aimed at studying the link between As, Cd, and Ni concentrations and BC by using a meta-analysis.Materials and methods: All case–control studies addressing the relationship between As, Cd, and Ni concentrations with BC were identified through electronic search databases (Scopus, ISI Web of Science, PubMed, EmBase, and Cochrane Library. The relevant data obtained from these papers were analyzed by a random-effects model. The heterogeneity of studies was secured by using I2 index. Funnel plots and Egger’s test were used to examine publication bias.Results: In the present study, due to different measurement methods used for measuring As, Cd, and Ni, the concentration of these elements was measured in various subgroups (1: plasma, 2: breast tissue, and 3: scalp hair and nail of individuals with BC and healthy subjects. The overall integration of data from the 3
Zhang, Yi; Zhang, Dian-Zhong
This research sought to summarize the evidence regarding the relationship between serum zinc level and metabolic syndrome (MetS). The electronic databases of PubMed, Web of Science, and Embase were searched up to October 2017 for observational studies on the association between serum zinc level and MetS. The standard mean difference (SMD) and its corresponding 95% confidence interval (CI) of the serum zinc level for MetS versus control participants were calculated. In addition, the pooled odds ratio (OR) and relative risk (RR) of MetS for the highest versus lowest category of serum zinc level, as well as their corresponding 95% CI, were also calculated. A total of 11 observational studies (8 cross-sectional, 1 case-control, and 2 cohort studies) were included in this meta-analysis. The combined SMD demonstrated that the serum zinc level in MetS was higher than that in control participants (SMD = 0.11; 95% CI, 0.03-0.19; p = 0.009). Moreover, the overall multivariable-adjusted RR showed that the increased serum zinc level was associated with a higher risk of MetS (RR = 1.82; 95% CI, 1.33-2.50; p level and MetS (OR = 1.00; 95% CI, 0.99-1.01; p = 0.841). Although the serum zinc level in participants with MetS was significantly higher than that in control ones, the existing evidence was still insufficient to conclude a definite relationship between serum zinc level and MetS. More well-designed prospective cohort studies are needed to elaborate the concerned issues further.
Full Text Available Abstract Background Coffee consumption has been shown to be associated with cancer of various sites in epidemiological studies. However, there is no comprehensive overview of the substantial body of epidemiologic evidence. Methods We searched MEDLINE, EMBASE, Science Citation Index Expanded and bibliographies of retrieved articles. Prospective cohort studies were included if they reported relative risks (RRs and corresponding 95% confidence intervals (CIs of various cancers with respect to frequency of coffee intake. We did random-effects meta-analyses and meta-regressions of study-specific incremental estimates to determine the risk of cancer associated with 1 cup/day increment of coffee consumption. Results 59 studies, consisting of 40 independent cohorts, met the inclusion criteria. Compared with individuals who did not or seldom drink coffee per day, the pooled RR of cancer was 0.87 (95% CI, 0.82-0.92 for regular coffee drinkers, 0.89 (0.84-0.93 for low to moderate coffee drinkers, and 0.82 (0.74-0.89 for high drinkers. Overall, an increase in consumption of 1 cup of coffee per day was associated with a 3% reduced risk of cancers (RR, 0.97; 95% CI, 0.96-0.98. In subgroup analyses, we noted that, coffee drinking was associated with a reduced risk of bladder, breast, buccal and pharyngeal, colorectal, endometrial, esophageal, hepatocellular, leukemic, pancreatic, and prostate cancers. Conclusions Findings from this meta-analysis suggest that coffee consumption may reduce the total cancer incidence and it also has an inverse association with some type of cancers.
Saunders, Catherine L; Chiodini, Benedetta D; Sham, Pak; Lewis, Cathryn M; Abkevich, Victor; Adeyemo, Adebowale A; de Andrade, Mariza; Arya, Rector; Berenson, Gerald S; Blangero, John; Boehnke, Michael; Borecki, Ingrid B; Chagnon, Yvon C; Chen, Wei; Comuzzie, Anthony G; Deng, Hong-Wen; Duggirala, Ravindranath; Feitosa, Mary F; Froguel, Philippe; Hanson, Robert L; Hebebrand, Johannes; Huezo-Dias, Patricia; Kissebah, Ahmed H; Li, Weidong; Luke, Amy; Martin, Lisa J; Nash, Matthew; Ohman, Miina; Palmer, Lyle J; Peltonen, Leena; Perola, Markus; Price, R Arlen; Redline, Susan; Srinivasan, Sathanur R; Stern, Michael P; Stone, Steven; Stringham, Heather; Turner, Stephen; Wijmenga, Cisca; Collier, David A
The objective was to provide an overall assessment of genetic linkage data of BMI and BMI-defined obesity using a nonparametric genome scan meta-analysis. We identified 37 published studies containing data on over 31,000 individuals from more than >10,000 families and obtained genome-wide logarithm of the odds (LOD) scores, non-parametric linkage (NPL) scores, or maximum likelihood scores (MLS). BMI was analyzed in a pooled set of all studies, as a subgroup of 10 studies that used BMI-defined obesity, and for subgroups ascertained through type 2 diabetes, hypertension, or subjects of European ancestry. Bins at chromosome 13q13.2- q33.1, 12q23-q24.3 achieved suggestive evidence of linkage to BMI in the pooled analysis and samples ascertained for hypertension. Nominal evidence of linkage to these regions and suggestive evidence for 11q13.3-22.3 were also observed for BMI-defined obesity. The FTO obesity gene locus at 16q12.2 also showed nominal evidence for linkage. However, overall distribution of summed rank p values <0.05 is not different from that expected by chance. The strongest evidence was obtained in the families ascertained for hypertension at 9q31.1-qter and 12p11.21-q23 (p < 0.01). Despite having substantial statistical power, we did not unequivocally implicate specific loci for BMI or obesity. This may be because genes influencing adiposity are of very small effect, with substantial genetic heterogeneity and variable dependence on environmental factors. However, the observation that the FTO gene maps to one of the highest ranking bins for obesity is interesting and, while not a validation of this approach, indicates that other potential loci identified in this study should be investigated further.
Vaseghi, B; Zoghi, M; Jaberzadeh, S
The primary aim of this systematic review was to evaluate the effects of anodal transcranial direct current stimulation (a-tDCS) on sensory (STh) and pain thresholds (PTh) in healthy individuals and pain levels (PL) in patients with chronic pain. Electronic databases were searched for a-tDCS studies. Methodological quality was examined using the PEDro and Downs and Black (D&B) assessment tools. a-tDCS of the primary motor cortex (M1) increases both STh (Psensory cortex (S1) (P<0.05 with an effect size of 4.34). Likewise, PL decreased significantly in the patient group following application of a-tDCS to both the M1 and dorsolateral prefrontal cortex (DLPFC). The average decrease in visual analogue score was 14.9% and 19.3% after applying a-tDCS on the M1 and DLPFC. Moreover, meta-analysis showed that in all subgroups (except a-tDCS of S1) active a-tDCS and sham stimulation produced significant differences. This review provides evidence for the effectiveness of a-tDCS in increasing STh/PTh in healthy group and decreasing PL in patients. However, due to small sample sizes in the included studies, our results should be interpreted cautiously. Given the level of blinding did not considered in inclusion criteria, the result of current study should be interpreted with caution. Site of stimulation should have a differential effect over pain relief. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
Laskowski, Ryszard; Bednarska, Agnieszka J; Kramarz, Paulina E; Loureiro, Susana; Scheil, Volker; Kudłek, Joanna; Holmstrup, Martin
The paper addresses problems arising from effects of natural environmental factors on toxicity of pollutants to organisms. Most studies on interactions between toxicants and natural factors, including those completed in the EU project NoMiracle (Novel Methods for Integrated Risk Assessment of Cumulative Stressors in Europe) described herein, showed that effects of toxic chemicals on organisms can differ vastly depending purely on external conditions. We compiled data from 61 studies on effects of temperature, moisture and dissolved oxygen on toxicity of a range of chemicals representing pesticides, polycyclic aromatic hydrocarbons, plant protection products of bacterial origin and trace metals. In 62.3% cases significant interactions (pnatural factors and chemicals were found, reaching 100% for the effect of dissolved oxygen on toxicity of waterborne chemicals. The meta-analysis of the 61 studies showed that the null hypothesis assuming no interactions between toxic chemicals and natural environmental factors should be rejected at p=2.7 x 10(-82) (truncated product method probability). In a few cases of more complex experimental designs, also second-order interactions were found, indicating that natural factors can modify interactions among chemicals. Such data emphasize the necessity of including information on natural factors and their variation in time and across geographic regions in ecological risk assessment. This can be done only if appropriate ecotoxicological test designs are used, in which test organisms are exposed to toxicants at a range of environmental conditions. We advocate designing such tests for the second-tier ecological risk assessment procedures. Copyright 2010 Elsevier B.V. All rights reserved.
Koo, Hoon Jung; Kwon, Jung-Hye
A meta-analysis of empirical studies performed in Korea was conducted to systematically investigate the associations between the indices of Internet addiction (IA) and psychosocial variables. Systematic literature searches were carried out using the Korean Studies Information Service System, Research Information Sharing Service, Science Direct, Google Scholar, and references in review articles. The key words were Internet addiction, (Internet) game addiction, and pathological, problematic, and excessive Internet use. Only original research papers using Korean samples published from 1999 to 2012 and officially reviewed by peers were included for analysis. Ninety-five studies meeting the inclusion criteria were identified. The magnitude of the overall effect size of the intrapersonal variables associated with internet addiction was significantly higher than that of interpersonal variables. Specifically, IA demonstrated a medium to strong association with "escape from self" and "self-identity" as self-related variables. "Attention problem", "self-control", and "emotional regulation" as control and regulation-relation variables; "addiction and absorption traits" as temperament variables; "anger" and "aggression" as emotion and mood and variables; "negative stress coping" as coping variables were also associated with comparably larger effect sizes. Contrary to our expectation, the magnitude of the correlations between relational ability and quality, parental relationships and family functionality, and IA were found to be small. The strength of the association between IA and the risk and protective factors was found to be higher in younger age groups. The findings highlight a need for closer examination of psychosocial factors, especially intrapersonal variables when assessing high-risk individuals and designing intervention strategies for both general IA and Internet game addiction.
Koo, Hoon Jung
Purpose A meta-analysis of empirical studies performed in Korea was conducted to systematically investigate the associations between the indices of Internet addiction (IA) and psychosocial variables. Materials and Methods Systematic literature searches were carried out using the Korean Studies Information Service System, Research Information Sharing Service, Science Direct, Google Scholar, and references in review articles. The key words were Internet addiction, (Internet) game addiction, and pathological, problematic, and excessive Internet use. Only original research papers using Korean samples published from 1999 to 2012 and officially reviewed by peers were included for analysis. Ninety-five studies meeting the inclusion criteria were identified. Results The magnitude of the overall effect size of the intrapersonal variables associated with internet addiction was significantly higher than that of interpersonal variables. Specifically, IA demonstrated a medium to strong association with "escape from self" and "self-identity" as self-related variables. "Attention problem", "self-control", and "emotional regulation" as control and regulation-relation variables; "addiction and absorption traits" as temperament variables; "anger" and "aggression" as emotion and mood and variables; "negative stress coping" as coping variables were also associated with comparably larger effect sizes. Contrary to our expectation, the magnitude of the correlations between relational ability and quality, parental relationships and family functionality, and IA were found to be small. The strength of the association between IA and the risk and protective factors was found to be higher in younger age groups. Conclusion The findings highlight a need for closer examination of psychosocial factors, especially intrapersonal variables when assessing high-risk individuals and designing intervention strategies for both general IA and Internet game addiction. PMID:25323910
Tak, L.M.; Riese, H.; de Bock, G.H.; Manoharan, A.; Kok, I.C.; Rosmalen, J.G.M.
Autonomic nervous system (ANS) dysfunction is a potential mechanism connecting psychosocial stress to functional somatic disorders (FSD), such as chronic fatigue syndrome, fibromyalgia and irritable bowel syndrome. We present the first meta-analysis and systematic review of methodological study
Madsen, Ida E H; Hannerz, Harald; Nyberg, Solja T
scales that do not necessarily correspond to clinically diagnosed depression. In addition, a meta-analysis from 2008 indicated publication bias in the field. METHODS: This study protocol describes the planned design and analyses of an individual participant data meta-analysis, to examine whether job...... using random effects meta-analysis. DISCUSSION: The planned analyses will help clarify whether job strain is associated with an increased risk of clinically diagnosed unipolar depression. As the analysis is based on pre-planned study protocols and an individual participant data meta-analysis, the pooled......BACKGROUND: Previous studies have shown that gainfully employed individuals with high work demands and low control at work (denoted "job strain") are at increased risk of common mental disorders, including depression. Most existing studies have, however, measured depression using self-rated symptom...
Komrokji, Rami; Swern, Arlene S; Grinblatt, David; Lyons, Roger M; Tobiasson, Magnus; Silverman, Lewis R; Sayar, Hamid; Vij, Ravi; Fliss, Albert; Tu, Nora; Sugrue, Mary M
After erythropoiesis-stimulating agent (ESA) failure, lenalidomide and hypomethylating agents are the only remaining treatment options for most patients with lower-risk myelodysplastic syndromes (LR-MDS). Optimal choice of these agents as front-line therapy in non-del(5q) LR-MDS is unclear. Because azacitidine clinical data mainly describe experience in higher-risk MDS, we performed a meta-analysis of patient-level data to evaluate azacitidine in patients with red blood cell (RBC) transfusion-dependent LR-MDS. We searched English-language articles for prospective phase II and III azacitidine clinical trials and patient registries published between 2000 and 2015, and Embase abstracts from 2015 conferences. Patient-level data from identified relevant studies were provided by investigators. Meta-analyses followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Efficacy endpoints were RBC transfusion independence (TI) and Clinical Benefit (RBC-TI, erythroid response, and complete or partial remission, per International Working Group 2006 criteria for MDS). Data for 233 patients from 6 clinical studies and 1 registry study met criteria for inclusion in analyses. Overall, 90.3% of patients had non-del(5q) LR-MDS. Pooled estimates from random-effects models of RBC-TI and Clinical Benefit were 38.9% and 81.1%, respectively; for the ESA-refractory subgroup, they were 40.5% and 77.3%; and for patients with isolated anemia, they were 41.9% and 82.5%. In multivariate analyses, planned use of ≥6 azacitidine treatment cycles was significantly predictive of response. Azacitidine effects in these patients, most with non-del(5q) LR-MDS, were promising and generally similar to those reported for lenalidomide in similar patients. The choice of initial therapy is important because most patients eventually stop responding to front-line therapy and alternatives are limited. Lower-risk myelodysplastic syndromes (LR-MDS) are primarily characterized by
Full Text Available Brachial circumference (BC, also known as upper arm or mid arm circumference, can be used as an indicator of muscle mass and fat tissue, which are distributed differently in men and women. Analysis of anthropometric measures of peripheral fat distribution such as BC could help in understanding the complex pathophysiology behind overweight and obesity. The purpose of this study is to identify genetic variants associated with BC through a large-scale genome-wide association scan (GWAS meta-analysis. We used fixed-effects meta-analysis to synthesise summary results across 14 GWAS discovery and 4 replication cohorts comprising overall 22,376 individuals (12,031 women and 10,345 men of European ancestry. Individual analyses were carried out for men, women, and combined across sexes using linear regression and an additive genetic model: adjusted for age and adjusted for age and BMI. We prioritised signals for follow-up in two-stages. We did not detect any signals reaching genome-wide significance. The FTO rs9939609 SNP showed nominal evidence for association (p<0.05 in the age-adjusted strata for men and across both sexes. In this first GWAS meta-analysis for BC to date, we have not identified any genome-wide significant signals and do not observe robust association of previously established obesity loci with BC. Large-scale collaborations will be necessary to achieve higher power to detect loci underlying BC.
Pierre, Michael; DeHertogh, Benoît; Gaigneaux, Anthoula; DeMeulder, Bertrand; Berger, Fabrice; Bareke, Eric; Michiels, Carine; Depiereux, Eric
Metastasis is a major cancer-related cause of death. Recent studies have described metastasis pathways. However, the exact contribution of each pathway remains unclear. Another key feature of a tumor is the presence of hypoxic areas caused by a lack of oxygen at the center of the tumor. Hypoxia leads to the expression of pro-metastatic genes as well as the repression of anti-metastatic genes. As many Affymetrix datasets about metastasis and hypoxia are publicly available and not fully exploited, this study proposes to re-analyze these datasets to extract new information about the metastatic phenotype induced by hypoxia in different cancer cell lines. Affymetrix datasets about metastasis and/or hypoxia were downloaded from GEO and ArrayExpress. AffyProbeMiner and GCRMA packages were used for pre-processing and the Window Welch t test was used for processing. Three approaches of meta-analysis were eventually used for the selection of genes of interest. Three complementary approaches were used, that eventually selected 183 genes of interest. Out of these 183 genes, 99, among which the well known JUNB, FOS and TP63, have already been described in the literature to be involved in cancer. Moreover, 39 genes of those, such as SERPINE1 and MMP7, are known to regulate metastasis. Twenty-one genes including VEGFA and ID2 have also been described to be involved in the response to hypoxia. Lastly, DAVID classified those 183 genes in 24 different pathways, among which 8 are directly related to cancer while 5 others are related to proliferation and cell motility. A negative control composed of 183 random genes failed to provide such results. Interestingly, 6 pathways retrieved by DAVID with the 183 genes of interest concern pathogen recognition and phagocytosis. The proposed methodology was able to find genes actually known to be involved in cancer, metastasis and hypoxia and, thus, we propose that the other genes selected based on the same methodology are of prime interest in
Full Text Available Background: Acne vulgaris is one of the most common skin diseases with a multifactorial pathogenesis. Examination of the literature regarding the contribution of smoking to acne shows contradictory results. The aim of this study was to undertake a systematic review of the literature and meta-analysis about the association between acne and smoking. Methods: A systematic review and meta-analysis, when possible were performed. The literature review was based on Pubmed, Scopus and Google Scholar searches using the keywords “(smoking OR tobacco OR nicotine OR cigarettes AND acne”. Only cross-sectional studies were included. Meta-analyses were performed using the RevMan software version 5 for Windows. Four different meta-analyses were carried out: one evaluating the association between smoking habit and acne, one including data stratified by gender, one for studies with a quality score > 6, and one relating to acne classification. Results: Six studies were selected. The first meta-analysis, including all studies, showed a non significant role of smoke in the development of acne: OR 1.05 (95% CI: 0.66–1.67 with random effect estimate. The second meta-analyses, including data stratified by gender, showed a OR=0.99 (95% CI: 0.57–1.73 for males and a OR of 1.45 (95% CI: 0.08–24.64 for females, using random effect for the heterogeneity in both cases. The third meta-analysis, included studies with a quality score >6 resulted in an estimated OR= 0.69 (95% CI: 0.55–0.85: in this case it was possible to use the fixed effect estimate. The last meta-analysis, concerning the severity grading, showed a non-significant result: OR=1.09 (95% CI: 0.61–1.95 using the random effect approach. Conclusions: The first two meta-analyses found no signification association between smoking and
Background: Acne vulgaris is one of the most common skin diseases with a multifactorial pathogenesis. Examination of the literature regarding the contribution of smoking to acne shows contradictory results. The aim of this study was to undertake a systematic review of the literature and meta-analysis about the association between acne and smoking.
Methods: A systematic review and meta-analysis, when possible were performed. The literature review was based on Pubmed, Scopus and Google Scholar searches using the keywords “(smoking OR tobacco OR nicotine OR cigarettes AND acne”. Only cross-sectional studies were included. Meta-analyses were performed using the RevMan software version 5 for Windows. Four different meta-analyses were carried out: one evaluating the association between smoking habit and acne, one including data stratified by gender, one for studies with a quality score > 6, and one relating to acne classification.
Results: Six studies were selected. The first meta-analysis, including all studies, showed a non significant role of smoke in the development of acne: OR 1.05 (95% CI: 0.66–1.67 with random effect estimate. The second meta-analyses, including data stratified by gender, showed a OR=0.99 (95% CI: 0.57–1.73 for males and a OR of 1.45 (95% CI: 0.08–24.64 for females, using random effect for the heterogeneity in both cases. The third meta-analysis, included studies with a quality score >6 resulted in an estimated OR= 0.69 (95% CI: 0.55–0.85: in this case it was possible to use the fixed effect estimate. The last meta-analysis, concerning the severity grading, showed a non-significant result: OR=1.09 (95% CI: 0.61–1.95 using the random effect approach.
Conclusions: The first two meta-analyses found no signification association between smoking and
Full Text Available Hypertension is one of the leading causes of disease burden across the world. In China, the latest nationwide survey of prevalence of hypertension was ten year ago, and data in rural areas is little known. More information about hypertension prevalence could help to improve overall antihypertensive health care. We aimed to estimate the pooled prevalence of hypertension in rural areas of China.Comprehensive electronic searches of PubMed, Web of Knowledge, Chinese Web of Knowledge, Wangfang, Weipu and SinoMed databases were conducted to identify any study in each database published from January 1, 2004 to December 31, 2013, reporting the prevalence of hypertension in Chinese rural areas. Prevalence estimates were stratified by age, area, sex, publication year, and sample size. All statistical calculations were made using the Stata Version 11.0 (College Station, Texas and Statsdirect Version 2.7.9.We identified 124 studies with a total population of 3,735,534 in the present meta-analysis. Among people aged 18 years old in Chinese rural areas, the summarized prevalence is 22.81% (19.41%-26.41%. Subgroup analysis shows the following results: for male 24.46% (21.19%-27.89%, for female 22.17% (18.25%-26.35%. For 2004-2006: 18.94% (14.41%-23.94%, for 2007-2009, 21.24% (15.98%-27.01% for 2010-2013: 26.68%, (20.79%-33.02%. For Northern region 25.76% (22.36%-29.32%, for Southern region 19.30%, (15.48%-24.08%.The last decade witnessed the growth in prevalence of hypertension in rural areas of China compared with the fourth national investigation, which has climbed the same level as the urban area. Guidelines for screening and treatment of hypertension in rural areas need to be given enough attention.
Full Text Available Schistosomiasis is a water-borne, parasitic disease of major public health importance. There has been considerable effort for several decades towards the development of a vaccine against the disease. Numerous mouse experimental studies using attenuated Schistosoma mansoni parasites for vaccination have been published since the 1960s. However, to date, there has been no systematic review or meta-analysis of these data. The aim of this study is to identify measurable experimental conditions that affect the level of protection against re-infection with S. mansoni in mice vaccinated with radiation attenuated cercariae. Following a systematic review, a total of 755 observations were extracted from 105 articles (published 1963-2007 meeting the searching criteria. Random effects meta-regression models were used to identify the influential predictors.Three predictors were found to have statistically significant effects on the level of protection from vaccination: increasing numbers of immunizing parasites had a positive effect on fraction of protection whereas increasing radiation dose and time to challenge infection had negative effects. Models showed that the irradiated cercariae vaccine has the potential to achieve protection as high as 78% with a single dose vaccination. This declines slowly over time but remains high for at least 8 months after the last immunization. These findings provide insights into the optimal delivery of attenuated parasite vaccination and into the nature and development of protective vaccine induced immunity against schistosomiasis which may inform the formulation of human vaccines and the predicted duration of protection and thus frequency of booster vaccines.
Li, Ruijian; Yu, Liang; Lin, Sixiang; Wang, Lina; Dong, Xin; Yu, Lingxia; Li, Weiyi; Li, Baosheng
The use of involved field radiotherapy (IFRT) has generated concern about the increasing incidence of elective nodal failure (ENF) in contrast to elective nodal irradiation (ENI). This meta-analysis aimed to provide more reliable and up-to-date evidence on the incidence of ENF between IFRT and ENI. We searched three databases for eligible studies where locally advanced non-small cell lung cancer (NSCLC) patients received IFRT or ENI. Outcome of interest was the incidence of ENF. The fixed-effects model was used to pool outcomes across the studies. There were 3 RCTs and 3 cohort studies included with low risk of bias. There was no significant difference in incidence of ENF between IFRT and ENI either among RCTs (RR = 1.38, 95 % CI: 0.59-3.25, p = 0.46) or among cohort studies (RR = 0.99, 95 % CI: 0.46-2.10, p = 0.97). There was also no significant difference in incidence of ENF between IFRT and ENI when RCTs and cohort studies were combined (RR = 1.15, 95 % CI: 0.65-2.01, p = 0.64). I 2 of test for heterogeneity was 0 %. This meta-analysis provides more reliable and stable evidence that there is no significant difference in incidence of ENF between IFRT and ENI.
Zeng, Tianshu; Cai, Xiong; Kong, Wen
Graves’ disease (GD) is a common autoimmune disorder with a genetic predisposition. There is strong evidence to suggest that both Th1 and Th2 circulating cytokines are involved in the development of GD. In this study, we conducted a meta-analysis to assess the impact of seven variations of five IL-related genes on the susceptibility to GD. A total of 22 case-control studies involving 5338 GD patients and 6446 healthy controls were included. The results showed that only one SNP rs1800795 in IL-6 was significantly associated with GD in homozygous model (CC vs. GG: OR = 2.714, 95% CI = 1.047–7.039, p = 0.04), heterozygous model (CG vs. GG: OR = 1.295, 95% CI = 1.013–1.655, p = 0.039), dominant model (CC+CG vs. GG: OR = 1.418, 95% CI = 1.122–1.793, p = 0.003) and additive model (C vs. G: OR = 1.432, 95% CI = 1.087–1.886, p = 0.011).To explain the heterogeneity, we performed the subgroup analysis by ethnicity. The ethnicity stratification revealed that the association between rs1800795 and GD tended to be much stronger for Asian than European population in homozygous, dominant, recessive, and additive models. The remaining 6 SNPs in 4 genes did not show any significant association with GD in any genetic models. Together, our data support that rs1800795 within the IL-6 gene confers genetic susceptibility for GD. Future large-scale studies are required to validate the associations between IL-6 and others IL-related genes and GD. PMID:29228744
Travis, Ruth C; Balkwill, Angela; Fensom, Georgina K; Appleby, Paul N; Reeves, Gillian K; Wang, Xiao-Si; Roddam, Andrew W; Gathani, Toral; Peto, Richard; Green, Jane; Key, Timothy J; Beral, Valerie
It has been proposed that night shift work could increase breast cancer incidence. A 2007 World Health Organization review concluded, mainly from animal evidence, that shift work involving circadian disruption is probably carcinogenic to humans. We therefore aimed to generate prospective epidemiological evidence on night shift work and breast cancer incidence. Overall, 522 246 Million Women Study, 22 559 EPIC-Oxford, and 251 045 UK Biobank participants answered questions on shift work and were followed for incident cancer. Cox regression yielded multivariable-adjusted breast cancer incidence rate ratios (RRs) and 95% confidence intervals (CIs) for night shift work vs no night shift work, and likelihood ratio tests for interaction were used to assess heterogeneity. Our meta-analyses combined these and relative risks from the seven previously published prospective studies (1.4 million women in total), using inverse-variance weighted averages of the study-specific log RRs. In the Million Women Study, EPIC-Oxford, and UK Biobank, respectively, 673, 28, and 67 women who reported night shift work developed breast cancer, and the RRs for any vs no night shift work were 1.00 (95% CI = 0.92 to 1.08), 1.07 (95% CI = 0.71 to 1.62), and 0.78 (95% CI = 0.61 to 1.00). In the Million Women Study, the RR for 20 or more years of night shift work was 1.00 (95% CI = 0.81 to 1.23), with no statistically significant heterogeneity by sleep patterns or breast cancer risk factors. Our meta-analysis of all 10 prospective studies included 4660 breast cancers in women reporting night shift work; compared with other women, the combined relative risks were 0.99 (95% CI = 0.95 to 1.03) for any night shift work, 1.01 (95% CI = 0.93 to 1.10) for 20 or more years of night shift work, and 1.00 (95% CI = 0.87 to 1.14) for 30 or more years. The totality of the prospective evidence shows that night shift work, including long-term shift work, has little or no effect on
Schwingshackl, Lukas; Schwedhelm, Carolina; Hoffmann, Georg; Knüppel, Sven; Iqbal, Khalid; Andriolo, Violetta; Bechthold, Angela; Schlesinger, Sabrina; Boeing, Heiner
The aim of this systematic review and meta-analysis was to summarize the evidence on the relation of the intakes of 12 major food groups, including whole grains, refined grains, vegetables, fruits, nuts, legumes, eggs, dairy, fish, red meat, processed meat, and sugar-sweetened beverages (SSBs) with the risk of hypertension. PubMed, Scopus, and Web of Science were searched systematically until June 2017 for prospective studies having quantitatively investigated the above-mentioned foods. We conducted meta-analysis on the highest compared with the lowest intake categories and linear and nonlinear dose-response meta-analyses to analyze the association. Summary RRs and 95% CIs were estimated by using a random-effects model. Overall, 28 reports were included in the meta-analysis. An inverse association for the risk of hypertension was observed for 30 g whole grains/d (RR: 0.92; 95% CI: 0.87, 0.98), 100 g fruits/d (RR: 0.97; 95% CI: 0.96, 0.99), 28 g nuts/d (RR: 0.70; 95% CI: 0.45, 1.08), and 200 g dairy/d (RR: 0.95; 95% CI: 0.94, 0.97), whereas a positive association for 100 g red meat/d (RR: 1.14; 95% CI: 1.02, 1.28), 50 g processed meat/d (RR: 1.12; 95% CI: 1.00, 1.26), and 250 mL SSB/d (RR: 1.07; 95% CI: 1.04, 1.10) was seen in the linear dose-response meta-analysis. Indication for nonlinear relations of the intakes of whole grains, fruits, fish, and processed meats with the risk of hypertension was detected. In summary, this comprehensive dose-response meta-analysis of 28 reports identified optimal intakes of whole grains, fruits, nuts, legumes, dairy, red and processed meats, and SSBs related to the risk of hypertension. These findings need to be seen under the light of very-low to low quality of meta-evidence. However, the findings support the current dietary guidelines in the prevention of hypertension. © 2017 American Society for Nutrition.
Anderson, P.D.; Jané Llopis, E.
AIMS: A systematic review of studies testing the effectiveness of educational and practice base strategies to increase the involvement of primary health-care practitioners in the treatment of tobacco dependence. DATA SOURCES: MEDLINE, EMBASE, CINAHL and the Cochrane Library (1966-2001). Selection
. Furthermore, the combine of these studies, a meta-analysis, is expected to decrease the confidence limit and to countervail the confounding factors. This study reviewed the epidemiological studies on natural radiation exposure and tried to combine their results to prove the safety of natural radiation exposure. (author)
Full Text Available Abstract Background Prognostic factors are associated with the risk of a subsequent outcome in people with a given disease or health condition. Meta-analysis using individual participant data (IPD, where the raw data are synthesised from multiple studies, has been championed as the gold-standard for synthesising prognostic factor studies. We assessed the feasibility and conduct of this approach. Methods A systematic review to identify published IPD meta-analyses of prognostic factors studies, followed by detailed assessment of a random sample of 20 articles published from 2006. Six of these 20 articles were from the IMPACT (International Mission for Prognosis and Analysis of Clinical Trials in traumatic brain injury collaboration, for which additional information was also used from simultaneously published companion papers. Results Forty-eight published IPD meta-analyses of prognostic factors were identified up to March 2009. Only three were published before 2000 but thereafter a median of four articles exist per year, with traumatic brain injury the most active research field. Availability of IPD offered many advantages, such as checking modelling assumptions; analysing variables on their continuous scale with the possibility of assessing for non-linear relationships; and obtaining results adjusted for other variables. However, researchers also faced many challenges, such as large cost and time required to obtain and clean IPD; unavailable IPD for some studies; different sets of prognostic factors in each study; and variability in study methods of measurement. The IMPACT initiative is a leading example, and had generally strong design, methodological and statistical standards. Elsewhere, standards are not always as high and improvements in the conduct of IPD meta-analyses of prognostic factor studies are often needed; in particular, continuous variables are often categorised without reason; publication bias and availability bias are rarely
Versteegden, Luuk R M; de Jonge, Paul K J D; IntHout, Joanna; van Kuppevelt, Toin H; Oosterwijk, Egbert; Feitz, Wout F J; de Vries, Rob B M; Daamen, Willeke F
Urethra repair by tissue engineering has been extensively studied in laboratory animals and patients, but is not routinely used in clinical practice. To systematically investigate preclinical and clinical evidence of the efficacy of tissue engineering for urethra repair in order to stimulate translation of preclinical studies to the clinic. A systematic search strategy was applied in PubMed and EMBASE. Studies were independently screened for relevance by two reviewers, resulting in 80 preclinical and 23 clinical studies of which 63 and 13 were selected for meta-analysis to assess side effects, functionality, and study completion. Analyses for preclinical and clinical studies were performed separately. Full circumferential and inlay procedures were assessed independently. Evaluated parameters included seeding of cells and type of biomaterial. Meta-analysis revealed that cell seeding significantly reduced the probability of encountering side effects in preclinical studies. Remarkably though, cells were only sparsely used in the clinic (4/23 studies) and showed no significant reduction of side effects. ln 21 out of 23 clinical studies, decellularized templates were used, while in preclinical studies other biomaterials showed promising outcomes as well. No direct comparison to current clinical practice could be made due to the limited number of randomized controlled studies. Due to a lack of controlled (pre)clinical studies, the efficacy of tissue engineering for urethra repair could not be determined. Meta-analysis outcome measures were similar to current treatment options described in literature. Surprisingly, it appeared that favorable preclinical results, that is inclusion of cells, were not translated to the clinic. Improved (pre)clinical study designs may enhance clinical translation. We reviewed all available literature on urethral tissue engineering to assess the efficacy in preclinical and clinical studies. We show that improvements to (pre)clinical study
Yu, Ji-Guo; Huang, Qing; Zhou, Xiao-Fang; Ding, Yi; Li, Jing; Xiang, Yi
To evaluate and compare changes in retinal nerve fiber layer (RNFL) thickness in patients with the pseudoexfoliation syndrome (PXS) and healthy controls. Case-control studies were selected through an electronic search of the Cochrane Controlled Trials Register, PubMed, and Embase. Results were reviewed to ensure that the included studies met prespecified inclusion/exclusion criteria, and the quality of each study was assessed using the Newcastle-Ottawa Scale. All included studies measured average and 4-quadrant (temporal, superior, nasal, and inferior) RNFL thickness using optical coherence tomography (OCT). For the continuous outcomes, we calculated the weighted mean difference (WMD) and 95% confidence intervals (CIs). Eight case-control studies were included in this meta-analysis involving 225 eyes of PXS patients and 208 eyes of healthy controls in total. Statistical analysis revealed that the average RNFL thickness in PXS patients was significantly reduced compared to healthy controls (WMD = -6.91, 95% CI: -9.99 to -3.82, p < 0.0001). Additionally, differences in RNFL thickness in the superior quadrant (WMD = -10.68, 95% CI: -16.40 to -4.95, p = 0.0003), inferior quadrant (WMD = -8.20, 95% CI: -10.85 to -5.55, p < 0.00001), nasal quadrant (WMD = -3.05, 95% CI: -5.21 to -0.90, p = 0.005), and temporal quadrant (WMD = -6.39, 95% CI: -9.98 to -2.80, p = 0.0005) were all significant between the two groups. These results suggest that it is important to evaluate RNFL thickness and the optic nerve head through OCT in patients with PXS in order to determine early glaucomatous damage and start timely intervention prior to visual field loss. © 2017 S. Karger AG, Basel.
Full Text Available The Water Framework Directive (WFD is arguably the most ambitious piece of European Union (EU legislation in the field of water. The directive defines a general framework for integrated river basin management in Europe with a view to achieving "good water status" by 2015. Institutional novelties include, among others, water management at hydrological scales, the involvement of nonstate actors in water planning, and various economic principles, as well as a common strategy to support EU member states during the implementation of the directive. More than 15 years after the adoption of the WFD, and with the passing of an important milestone, 2015, we believe it is time for an interim assessment. This article provides a systematic review of existing scholarship on WFD implementation. We identify well-documented areas of research, describe largely unchartered territories, and suggest avenues for future studies. Methodologically, we relied on a meta-analysis. Based on a codebook of more than 35 items, we analyzed 89 journal articles reporting on the implementation of the directive in EU member states. Our review is organized around three major themes. The first is "who, when, and where"; we explore publication patterns, thereby looking into authors, timelines, and target journals. The second is "what"; we analyze the object of study in our source articles with a particular focus on case study countries, policy levels, the temporal stage of WFD implementation, and if the directive was not studied in its entirety, the aspect of the WFD that received scholarly attention. The third is "how," i.e., theoretical and methodological choices made when studying the WFD.
Hollemans, Robbert A; Hallensleben, Nora D L; Mager, David J; Kelder, Johannes C; Besselink, Marc G; Bruno, Marco J; Verdonk, Robert C; van Santvoort, Hjalmar C
This study systematically explores the prevalence of pancreatic exocrine insufficiency (PEI) after acute pancreatitis in different subgroups of etiology (biliary/alcoholic/other), disease severity and follow-up time ( 36 months after index admission). PubMed and EMBASE databases were searched, 32 studies were included in this study level meta-analysis. In a total of 1495 patients with acute pancreatitis, tested at a mean of 36 months after index admission, the pooled prevalence of PEI was 27.1% (95%-confidence interval [CI]: 20.3%-35.1%). Patients from seven studies (n = 194) underwent direct tests with pooled prevalence of 41.7% [18.5%-69.2%]. Patients from 26 studies (n = 1305) underwent indirect tests with pooled prevalence of 24.4% [18.3%-31.8%]. In subgroup analyses on patients that underwent fecal elastase-1 tests, PEI occurred more often in alcoholic pancreatitis (22.7% [16.6%-30.1%]) than in biliary pancreatitis (10.2% [6.2%-16.4%]) or other etiology (13.4% [7.7%-22.4%]; P = 0.02). Pooled prevalence of PEI after mild and severe pancreatitis was 19.4% [8.6%-38.2%] and 33.4% [22.6%-46.3%] respectively in studies using fecal elaste-1 tests (P = 0.049). Similar results were seen in patients without (18.9% [9.3%-34.6%]) and with necrotizing pancreatitis (32.0% [18.2%-49.8%]; P = 0.053). Over time, the prevalence of PEI decreased in patients who underwent the fecal elastase-1 test and increased in patients who underwent the fecal fat analysis. After acute pancreatitis, a quarter of all patients develop PEI during follow-up. Alcoholic etiology and severe and necrotizing pancreatitis are associated with higher risk of PEI. The prevalence of PEI may change as time of follow-up increases. Copyright © 2018 IAP and EPC. Published by Elsevier B.V. All rights reserved.
.Conclusion: The cosmetically tinted lenses evaluated in this meta-analysis appear to be safe when properly prescribed by an eye care professional and used in a compliant manner.Keywords: contact lens, hydrogel, cosmetically tinted contact lens, compliance
Wu, L; Sun, D; He, Y
The role of dietary factors on chronic diseases seems essential in the potentially adverse or preventive effects. However, no evidence of dose-response meta-analysis of prospective cohort studies has verified the association between the intake of fruit and/or vegetables and the risk of developing hypertension. The PubMed and Embase were searched for prospective cohort studies. A generic inverse-variance method with random effects model was used to calculate the pooled relative risks (RRs) and 95% confidence intervals (CIs). Generalized least squares trend estimation model was used to calculate the study-specific slopes for the dose-response analyses. Seven articles comprised nine cohorts involving 185 676 participants were assessed. The highest intake of fruit or vegetables separately, and total fruit and vegetables were inversely associated with the incident risk of hypertension compared with the lowest level, and the pooled RRs and 95% CIs were 0.87 (0.79, 0.95), 0.88 (0.79, 0.99) and 0.90 (0.84, 0.98), respectively. We also found an inverse dose-response relation between the risk of developing hypertension and fruit intake, and total fruit and vegetables consumption. The incident risk of hypertension was decreased by 1.9% for each serving per day of fruit consumption, and decreased by 1.2% for each serving per day of total fruit and vegetables consumption. Our results support the recommendation to increase the consumption of fruit and vegetables with respect to preventing the risk of developing hypertension. However, further large prospective studies and long-term high-quality randomized controlled trials are still needed to confirm the observed association.
Meng Zhao; Xiao-yan Li; Chun-ying Xu; Li-ping Zou
OBJECTIVE:China is the only country where nerve growth factor is approved for large-scale use as a clinical medicine. More than 10 years ago, in 2003, nerve growth factor injection was listed as a national drug. The goal of this article is to evaluate comprehensively the efifcacy and safety of nerve growth factor for the treatment of neurological diseases. DATA RETRIEVAL:A computer-based retrieval was performed from six databases, including the Cochrane Library, PubMed, EMBASE, Sino Med, CNKI, and the VIP database, searching from the clinical establishment of nerve growth factor for treatment until December 31, 2013. The key words for the searches were “nerve growth factor, randomized controlled trials” in Chinese and in English. DATA SELECTION:Inclusion criteria: any study published in English or Chinese referring to randomized controlled trials of nerve growth factor; patients with neurological diseases such as peripheral nerve injury, central nerve injury, cranial neuropathy, and nervous system infections;patients older than 7 years; similar research methods and outcomes assessing symptoms; and measurement of nerve conduction velocities. The meta-analysis was conducted using Review Manager 5.2.3 software. MAIN OUTCOME MEASURES:The total effective rate, the incidence of adverse effects, and the nerve conduction velocity were recorded for each study. RESULTS:Sixty-four studies involving 6,297 patients with neurological diseases were included. The total effective rate in the group treated with nerve growth factor was significantly higher than that in the control group (P < 0.0001,RR: 1.35, 95%CI: 1.30–1.40). The average nerve conduction velocity in the nerve growth factor group was signiifcantly higher than that in the control group (P < 0.00001,MD: 4.59 m/s, 95%CI: 4.12–5.06). The incidence of pain or sclero-ma at the injection site in the nerve growth factor group was also higher than that in the control group (P < 0.00001,RR: 6.30, 95%CI: 3.53–11
Tipton, Elizabeth; Shuster, Jonathan
Bland-Altman method comparison studies are common in the medical sciences and are used to compare a new measure to a gold-standard (often costlier or more invasive) measure. The distribution of these differences is summarized by two statistics, the 'bias' and standard deviation, and these measures are combined to provide estimates of the limits of agreement (LoA). When these LoA are within the bounds of clinically insignificant differences, the new non-invasive measure is preferred. Very often, multiple Bland-Altman studies have been conducted comparing the same two measures, and random-effects meta-analysis provides a means to pool these estimates. We provide a framework for the meta-analysis of Bland-Altman studies, including methods for estimating the LoA and measures of uncertainty (i.e., confidence intervals). Importantly, these LoA are likely to be wider than those typically reported in Bland-Altman meta-analyses. Frequently, Bland-Altman studies report results based on repeated measures designs but do not properly adjust for this design in the analysis. Meta-analyses of Bland-Altman studies frequently exclude these studies for this reason. We provide a meta-analytic approach that allows inclusion of estimates from these studies. This includes adjustments to the estimate of the standard deviation and a method for pooling the estimates based upon robust variance estimation. An example is included based on a previously published meta-analysis. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Statistical power is important in a meta-analysis study, although few studies have examined the performance of simulated power in meta-analysis. The purpose of this study is to inform researchers about statistical power estimation on two sample mean difference test under different situations: (1) the discrepancy between the analytical power and…
Full Text Available We aimed to identify the consistent regions of gray matter volume (GMV abnormalities in idiopathic generalized epilepsy (IGE, and to study the difference of GMV abnormalities among IGE subsyndromes by applying activation likelihood estimation (ALE meta-analysis.A systematic review of VBM studies on GMV of patients with absence epilepsy (AE, juvenile myoclonic epilepsy (JME, IGE and controls indexed in PubMed and ScienceDirect from January 1999 to June 2016 was conducted. A total of 12 IGE studies, including 7 JME and 3 AE studies, were selected. Meta-analysis was performed on these studies by using the pooled and within-subtypes analysis (www.brainmap.org. Based on the above results, between-subtypes contrast analysis was carried out to detect the abnormal GMV regions common in and unique to each subtype as well.IGE demonstrated significant GMV increase in right ventral lateral nucleus (VL and right medial frontal gyrus, and significant GMV decrease in bilateral pulvinar. For JME, significant GMV increase was seen in right medial frontal gyrus, right anterior cingulate cortex (ACC, while significant GMV decrease was found in right pulvinar. In AE, the most significant GMV increase was found in right VL, and slight GMV reduction was seen in right medial dorsal nucleus, right subcallosal gyrus, left caudate and left precuneus. No overlapped and unique regions with significant GMV abnormalities were found between JME and AE.This meta-analysis demonstrated that thalamo-frontal network was a structure with significant GMV abnormality in IGE, and the IGE subsyndromes showed different GMV abnormal regions. These observations may provide instructions on the clinical diagnosis of IGE.
Cooper, Andrew J; Forouhi, Nita G; Ye, Zheng; Buijsse, Brian; Arriola, Larraitz; Balkau, Beverley; Barricarte, Aurelio; Beulens, Joline WJ; Boeing, Heiner; Büchner, Frederike L; Dahm, Christina C; de Lauzon-Guillain, Blandine; Fagherazzi, Guy; Franks, Paul W; Gonzalez, Carlos; Grioni, Sara; Kaaks, Rudolf; Key, Timothy J; Masala, Giovanna; Navarro, Carmen; Nilsson, Peter; Overvad, Kim; Panico, Salvatore; Quirós, Jose Ramón; Rolandsson, Olov; Roswall, Nina; Sacerdote, Carlotta; Sánchez, María-José; Slimani, Nadia; Sluijs, Ivonne; Spijkerman, Annemieke MW; Teucher, Birgit; Tjonneland, Anne; Tumino, Rosario; Sharp, Stephen J; Langenberg, Claudia; Feskens, Edith JM; Riboli, Elio; Wareham, Nicholas J
Background/Objective Fruit and vegetable intake (FVI) may reduce the risk of type 2 diabetes (T2D), but the epidemiological evidence is inconclusive. The aim of this study is to examine the prospective association of FVI with T2D and conduct an updated meta-analysis. Subjects/Methods In the EPIC-InterAct (European Prospective Investigation into Cancer-InterAct) prospective case-cohort study nested within eight European countries, a representative sample of 16 154 participants and 12 403 incident cases of T2D were identified from 340 234 individuals with 3.99 million person-years of follow-up. For the meta-analysis we identified prospective studies on FVI and T2D risk by systematic searches of MEDLINE and EMBASE until April 2011. Results In EPIC-InterAct, estimated FVI by dietary questionnaires varied more than two-fold between countries. In adjusted analyses the hazard ratio (95% confidence interval) comparing the highest with lowest quartile of reported intake was 0.90 (0.80-1.01) for FVI; 0.89 (0.76-1.04) for fruit, and 0.94 (0.84-1.05) for vegetables. Among FV sub-types, only root vegetables were inversely associated with diabetes 0.87 (0.77-0.99). In meta-analysis using pooled data from five studies including EPIC-InterAct, comparing the highest with lowest category for FVI was associated with a lower relative risk of diabetes (0.93 (0.87-1.00)). Fruit or vegetables separately were not associated with diabetes. Among FV sub-types, only green leafy vegetable intake (RR: 0.84 (0.74-0.94)) was inversely associated with diabetes. Conclusions Sub-types of vegetables, such as root vegetables or green leafy vegetables may be beneficial for the prevention of diabetes, while total FVI may exert a weaker overall effect. PMID:22854878
Wu, Lei; Sun, Dali
Previous systematic reviews and meta-analyses have evaluated the association of dairy consumption and the risk of cardiovascular disease (CVD). However, the findings were inconsistent. No quantitative analysis has specifically assessed the effect of yogurt intake on the incident risk of CVD. We searched the PubMed and the Embase databases from inception to 10 January 2017. A generic inverse-variance method was used to pool the fully-adjusted relative risks (RRs) and the corresponding 95% confidence intervals (CIs) with a random-effects model. A generalized least squares trend estimation model was used to calculate the specific slopes in the dose-response analysis. The present systematic review and meta-analysis identified nine prospective cohort articles involving a total of 291,236 participants. Compared with the lowest category, highest category of yogurt consumption was not significantly related with the incident risk of CVD, and the RR (95% CI) was 1.01 (0.95, 1.08) with an evidence of significant heterogeneity (I² = 52%). However, intake of ≥200 g/day yogurt was significantly associated with a lower risk of CVD in the subgroup analysis. There was a trend that a higher level of yogurt consumption was associated with a lower incident risk of CVD in the dose-response analysis. A daily dose of ≥200 g yogurt intake might be associated with a lower incident risk of CVD. Further cohort studies and randomized controlled trials are still demanded to establish and confirm the observed association in populations with different characteristics.
Sarah L. Kerns
Full Text Available Nearly 50% of cancer patients undergo radiotherapy. Late radiotherapy toxicity affects quality-of-life in long-term cancer survivors and risk of side-effects in a minority limits doses prescribed to the majority of patients. Development of a test predicting risk of toxicity could benefit many cancer patients. We aimed to meta-analyze individual level data from four genome-wide association studies from prostate cancer radiotherapy cohorts including 1564 men to identify genetic markers of toxicity. Prospectively assessed two-year toxicity endpoints (urinary frequency, decreased urine stream, rectal bleeding, overall toxicity and single nucleotide polymorphism (SNP associations were tested using multivariable regression, adjusting for clinical and patient-related risk factors. A fixed-effects meta-analysis identified two SNPs: rs17599026 on 5q31.2 with urinary frequency (odds ratio [OR] 3.12, 95% confidence interval [CI] 2.08–4.69, p-value 4.16 × 10−8 and rs7720298 on 5p15.2 with decreased urine stream (OR 2.71, 95% CI 1.90–3.86, p-value = 3.21 × 10−8. These SNPs lie within genes that are expressed in tissues adversely affected by pelvic radiotherapy including bladder, kidney, rectum and small intestine. The results show that heterogeneous radiotherapy cohorts can be combined to identify new moderate-penetrance genetic variants associated with radiotherapy toxicity. The work provides a basis for larger collaborative efforts to identify enough variants for a future test involving polygenic risk profiling.
Tepjan, Suchon; Rubincam, Clara; Doukas, Nick; Asey, Farid
Objective To examine factors associated with parents’ uptake of human papillomavirus (HPV) vaccines for their children. Design Systematic review and meta-analysis. Data sources Cochrane Library, AIDSLINE, CINAHL, EMBASE, PsycINFO, Social Sciences Abstracts, Ovid MEDLINE, Scholars Portal, Social Sciences Citation Index and Dissertation Abstracts International from inception through November 2017. Methods We included studies that sampled parents and assessed uptake of HPV vaccines for their children (≤18 years) and/or sociodemographics, knowledge, attitudes or other factors associated with uptake. Study risk of bias was assessed using the Effective Public Health Practice Project tool. We pooled data using random-effects meta-analysis and conducted moderation analyses to examine variance in uptake by sex of child and parent. Results Seventy-nine studies on 840 838 parents across 15 countries were included. The pooled proportion of parents’ uptake of HPV vaccines for their children was 41.5% (range: 0.7%–92.8%), twofold higher for girls (46.5%) than for boys (20.3%). In the meta-analysis of 62 studies, physician recommendation (r=0.46 (95% CI 0.34 to 0.56)) had the greatest influence on parents’ uptake, followed by HPV vaccine safety concerns (r=−0.31 (95% CI −0.41 to −0.16)), routine child preventive check-up, past 12 months (r=0.22 (95% CI 0.11 to 0.33)) and parents’ belief in vaccines (r=0.19 (95% CI 0.08 to 0.29)). Health insurance-covered HPV vaccination (r=0.16 (95% CI 0.04 to 0.29)) and lower out-of-pocket cost (r=−0.15 (95% CI −0.22 to −0.07)) had significant effects on uptake. We found significant moderator effects for sex of child. Conclusions Findings indicate suboptimal levels of HPV vaccine uptake, twofold lower among boys, that may be improved by increasing physician recommendations, addressing parental safety concerns and promoting parents’ positive beliefs about vaccines, in addition to expanding insurance coverage and
Newman, Peter A; Logie, Carmen H; Lacombe-Duncan, Ashley; Baiden, Philip; Tepjan, Suchon; Rubincam, Clara; Doukas, Nick; Asey, Farid
To examine factors associated with parents' uptake of human papillomavirus (HPV) vaccines for their children. Systematic review and meta-analysis. Cochrane Library, AIDSLINE, CINAHL, EMBASE, PsycINFO, Social Sciences Abstracts, Ovid MEDLINE, Scholars Portal, Social Sciences Citation Index and Dissertation Abstracts International from inception through November 2017. We included studies that sampled parents and assessed uptake of HPV vaccines for their children (≤18 years) and/or sociodemographics, knowledge, attitudes or other factors associated with uptake. Study risk of bias was assessed using the Effective Public Health Practice Project tool. We pooled data using random-effects meta-analysis and conducted moderation analyses to examine variance in uptake by sex of child and parent. Seventy-nine studies on 840 838 parents across 15 countries were included. The pooled proportion of parents' uptake of HPV vaccines for their children was 41.5% (range: 0.7%-92.8%), twofold higher for girls (46.5%) than for boys (20.3%). In the meta-analysis of 62 studies, physician recommendation (r=0.46 (95% CI 0.34 to 0.56)) had the greatest influence on parents' uptake, followed by HPV vaccine safety concerns (r=-0.31 (95% CI -0.41 to -0.16)), routine child preventive check-up, past 12 months (r=0.22 (95% CI 0.11 to 0.33)) and parents' belief in vaccines (r=0.19 (95% CI 0.08 to 0.29)). Health insurance-covered HPV vaccination (r=0.16 (95% CI 0.04 to 0.29)) and lower out-of-pocket cost (r=-0.15 (95% CI -0.22 to -0.07)) had significant effects on uptake. We found significant moderator effects for sex of child. Findings indicate suboptimal levels of HPV vaccine uptake, twofold lower among boys, that may be improved by increasing physician recommendations, addressing parental safety concerns and promoting parents' positive beliefs about vaccines, in addition to expanding insurance coverage and reducing out-of-pocket costs. Limitations of this meta-analysis include the lack of
Helen L Storey
Full Text Available Novel typhoid diagnostics currently under development have the potential to improve clinical care, surveillance, and the disease burden estimates that support vaccine introduction. Blood culture is most often used as the reference method to evaluate the accuracy of new typhoid tests; however, it is recognized to be an imperfect gold standard. If no single gold standard test exists, use of a composite reference standard (CRS can improve estimation of diagnostic accuracy. Numerous studies have used a CRS to evaluate new typhoid diagnostics; however, there is no consensus on an appropriate CRS. In order to evaluate existing tests for use as a reference test or inclusion in a CRS, we performed a systematic review of the typhoid literature to include all index/reference test combinations observed. We described the landscape of comparisons performed, showed results of a meta-analysis on the accuracy of the more common combinations, and evaluated sources of variability based on study quality. This wide-ranging meta-analysis suggests that no single test has sufficiently good performance but some existing diagnostics may be useful as part of a CRS. Additionally, based on findings from the meta-analysis and a constructed numerical example demonstrating the use of CRS, we proposed necessary criteria and potential components of a typhoid CRS to guide future recommendations. Agreement and adoption by all investigators of a standardized CRS is requisite, and would improve comparison of new diagnostics across independent studies, leading to the identification of a better reference test and improved confidence in prevalence estimates.
Davey, Sanjeev; Davey, Anuradha
There is a considerable debate on addiction and abuse to Smartphone among adolescents and its consequent impact on their health; not only in a global context, but also specifically in the Indian population; considering that Smartphone's, globally occupy more than 50% of mobile phones market and more precise quantification of the associated problems is important to facilitate understanding in this field. As per PRISMA (2009) guidelines, extensive search of various studies in any form from a global scale to the more narrow Indian context using two key search words: “Smartphone's addiction” and “Indian adolescents” was done using websites of EMBASE, MEDLINE, PubMed, Global Health, Psyc-INFO, Biomed-Central, Web of Science, Cochrane Library, world library - World-Cat, Indian libraries such as National Medical Library of India from 1 January, 1995 to March 31, 2014 first for systematic-review. Finally, meta-analysis on only Indian studies was done using Med-Calc online software capable of doing meta-analysis of proportions. A total of 45 articles were considered in systematic-review from whole world; later on 6 studies out of these 45 related to Smartphone's addiction in India were extracted to perform meta-analysis, in which total 1304 participants (range: 165-335) were enrolled. The smartphone addiction magnitude in India ranged from 39% to 44% as per fixed effects calculated (P Smartphone addiction among Indian teens can not only damage interpersonal skills, but also it can lead to significant negative health risks and harmful psychological effects on Indian adolescents. PMID:25709785
Full Text Available There is a considerable debate on addiction and abuse to Smartphone among adolescents and its consequent impact on their health; not only in a global context, but also specifically in the Indian population; considering that Smartphone′s, globally occupy more than 50% of mobile phones market and more precise quantification of the associated problems is important to facilitate understanding in this field. As per PRISMA (2009 guidelines, extensive search of various studies in any form from a global scale to the more narrow Indian context using two key search words: "Smartphone′s addiction" and "Indian adolescents" was done using websites of EMBASE, MEDLINE, PubMed, Global Health, Psyc-INFO, Biomed-Central, Web of Science, Cochrane Library, world library - World-Cat, Indian libraries such as National Medical Library of India from 1 January, 1995 to March 31, 2014 first for systematic-review. Finally, meta-analysis on only Indian studies was done using Med-Calc online software capable of doing meta-analysis of proportions. A total of 45 articles were considered in systematic-review from whole world; later on 6 studies out of these 45 related to Smartphone′s addiction in India were extracted to perform meta-analysis, in which total 1304 participants (range: 165-335 were enrolled. The smartphone addiction magnitude in India ranged from 39% to 44% as per fixed effects calculated (P < 0.0001. Smartphone addiction among Indian teens can not only damage interpersonal skills, but also it can lead to significant negative health risks and harmful psychological effects on Indian adolescents.
Davey, Sanjeev; Davey, Anuradha
There is a considerable debate on addiction and abuse to Smartphone among adolescents and its consequent impact on their health; not only in a global context, but also specifically in the Indian population; considering that Smartphone's, globally occupy more than 50% of mobile phones market and more precise quantification of the associated problems is important to facilitate understanding in this field. As per PRISMA (2009) guidelines, extensive search of various studies in any form from a global scale to the more narrow Indian context using two key search words: "Smartphone's addiction" and "Indian adolescents" was done using websites of EMBASE, MEDLINE, PubMed, Global Health, Psyc-INFO, Biomed-Central, Web of Science, Cochrane Library, world library - World-Cat, Indian libraries such as National Medical Library of India from 1 January, 1995 to March 31, 2014 first for systematic-review. Finally, meta-analysis on only Indian studies was done using Med-Calc online software capable of doing meta-analysis of proportions. A total of 45 articles were considered in systematic-review from whole world; later on 6 studies out of these 45 related to Smartphone's addiction in India were extracted to perform meta-analysis, in which total 1304 participants (range: 165-335) were enrolled. The smartphone addiction magnitude in India ranged from 39% to 44% as per fixed effects calculated (P Smartphone addiction among Indian teens can not only damage interpersonal skills, but also it can lead to significant negative health risks and harmful psychological effects on Indian adolescents.
Azim, Hatem A; Santoro, Luigi; Pavlidis, Nicholas
Due to the rising trend of delaying pregnancy to later in life, more women are diagnosed with breast cancer before completing their families. Therefore, enquiry into the feasibility and safety of pregnancy following breast cancer diagnosis is on the rise. Available evidence suggests that women...... with a history of breast cancer are frequently advised against future conception for fear that pregnancy could adversely affect their breast cancer outcome. Hence, we conducted a meta-analysis to understand the effect of pregnancy on overall survival of women with a history of breast cancer....
Azim, Hatem A; Santoro, Luigi; Pavlidis, Nicholas
with a history of breast cancer are frequently advised against future conception for fear that pregnancy could adversely affect their breast cancer outcome. Hence, we conducted a meta-analysis to understand the effect of pregnancy on overall survival of women with a history of breast cancer.......Due to the rising trend of delaying pregnancy to later in life, more women are diagnosed with breast cancer before completing their families. Therefore, enquiry into the feasibility and safety of pregnancy following breast cancer diagnosis is on the rise. Available evidence suggests that women...
Full Text Available Methylenetetrahydrofolate reductase (MTHFR is an important enzyme of folate and methionine metabolism, making it crucial for DNA synthesis and methylation. The objective of this study was to analyze MTHFR gene 677C>T polymorphism in infertile male individuals from North India, followed by a meta-analysis on our data and published studies.We undertook genotyping on a total of 837 individuals including well characterized infertile (N = 522 and confirmed fertile (N = 315 individuals. The SNP was typed by direct DNA sequencing. Chi square test was done for statistical analysis. Published studies were searched using appropriate keywords. Source of data collection for meta-analysis included 'Pubmed', 'Ovid' and 'Google Scholar'. Those studies analyzing 677C>T polymorphism in male infertility and presenting all relevant data were included in meta-analysis. The genotype data for infertile subjects and fertile controls was extracted from each study. Chi square test was done to obtain odds ratio (OR and p-value. Meta-analysis was performed using Comprehensive Meta-analysis software (Version 2. The frequency of mutant (T allele (p = 0.0025 and genotypes (CT+TT (p = 0.0187 was significantly higher in infertile individuals in comparison to fertile controls in our case-control study. The overall summary estimate (OR for allele and genotype meta-analysis were 1.304 (p = 0.000, 1.310 (p = 0.000, respectively, establishing significant association of 677C>T polymorphism with male infertility.677C>T substitution associated strongly with male infertility in Indian population. Allele and genotype meta-analysis also supported its strong correlation with male infertility, thus establishing it as a risk factor.
Full Text Available Abstract Objectives: to summarize Brazilian studies that analyzed the risk factors for Exclusive Breastfeeding (EBF interruption before the child's six months of life. Methods: systematic review and meta-analysis indexed articles from Bireme, Scielo and Pubmed databases published in the period of January 2000 to December 2015. Results: 22 articles were included in the meta-analysis. The factors related to newborns were observed, such as birth weight (OR= 1.17; CI 95%: 1.05-1.29, female gender (OR= 1,09; CI 95%: 1.04-1.13 and the use of pacifier (OR= 2.29; CI 95%: 1.68-2.91 were the main factors responsible for the increase in the occurrence of EBF interruption. The factors were related to the mother, maternal age below twenty years old (OR= 1.22; CI 95%: 1.12-1.33 low schooling level (OR=1.28; CI 95%: 1.11-1.45, primiparity (OR= 1.17; CI 95%: 1.02-1.32 maternal employment during the postpartum period (OR= 1.26; CI 95%: 1.11-1.41, and low family income (OR= 1.22; CI 95%: 1.08-1.37 contributed significantly to the EBF interruption . Conclusions: the meta-analysis of Brazilian epidemiological studies demonstrated evidences to conclude that below the age of twenty, low schooling, primiparity, maternal employment in the postpartum period and low family income are associated to the interruption of exclusive breastfeeding until 6 months of age. Children with low birth weight, female gender and used a pacifier had greater vulnerability to not be exclusively breastfed. In conclusion, most of these factors can be modified through appropriate public policies throughout the adequate prenatal period to promote exclusive breastfeeding.
Objectives This meta-analysis aimed to evaluate congenital malformations in infants conceived by assisted reproductive techniques (ART), compared with infants conceived spontaneously. Methods In this study, available resources searched to find relevant articles included PubMed, ScienceDirect, Scopus, Google Scholar, Cochrane, ProQuest, Iranmedex, Magiran, and Scientific Information Database. After extracting the necessary information from evaluated articles, meta-analysis on the articles’ data was performed using Stata version 11.2. Results In this study, from a total of 339 articles, extracted from the initial investigation, ultimately 30 articles were selected for meta-analysis that assessed the use of ART on the risk of congenital abnormalities and some birth complications on 5 470 181 infants (315 402 cases and 5 154 779 controls). The odds ratio (95% confidence interval [CI]) for low birth weight was 1.89 (95% CI, 1.36 to 2.62), preterm labor 1.79 (95% CI, 1.21 to 2.63), cardiac abnormalities 1.43 (95% CI, 1.27 to 1.62), central nervous system abnormalities 1.36 (95% CI, 1.10 to 1.70), urogenital system abnormalities 1.58 (95% CI, 1.28 to 1.94), musculoskeletal disorders 1.35 (95% CI, 1.12 to 1.64), and chromosomal abnormalities in infants conceived by ART was 1.14 (95% CI, 0.90 to 1.44), which were all statistically significant, except chromosomal abnormalities. Conclusions The risk of congenital abnormalities and some birth complications were significantly higher in ART than normal conception, while chromosomal abnormalities were not; therefore, the application of ART should be selected individually for patients by detailed assessment to reduce such risks in the population. PMID:29207452
Full Text Available Methylenetetrahydrofolate reductase (MTHFR is a key enzyme of folate metabolic pathway which catalyzes the irreversible conversion of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. 5-methyltetrahydrofolate donates methyl group for the methylation of homocysteine to methionine. Several studies have investigated maternal MTHFR C677T polymorphism as a risk factor for DS, but the results were controversial and inconclusive. To come into a conclusive estimate, authors performed a meta-analysis.A meta-analysis of published case control studies was performed to investigate the association between maternal MTHFR C677T polymorphism and Down syndrome.PubMed, Google Scholar, Elsevier, Springer Link databases were searched to select the eligible case control studies using appropriate keywords. The pooled odds ratio (OR with 95%confidence interval were calculated for risk assessment.Thirty four studies with 3,098 DS case mothers and 4,852 control mothers were included in the present meta-analysis. The pooled OR was estimated under five genetic models and significant association was found between maternal MTHFR 677C>T polymorphism and Down syndrome under four genetic models except recessive model (for T vs. C, OR = 1.26, 95% CI = 1.09-1.46, p = 0.001; for TT vs. CC, OR = 1.49, 95% CI = 1.13-1.97, p = 0.008; for CT vs. CC, OR = 1.29, 95% CI = 1.10-1.51, p = 0.001; for TT+CT vs. CC, OR = 1.35, 95% CI = 1.13-1.60, p = 0.0008; for TT vs. CT+CC, OR = 0.76, 95% CI = 0.60-0.94, p = 0.01.The results of the present meta-analysis support that maternal MTHFR C677T polymorphism is a risk factor for DS- affected pregnancy.
Yang, Hui-Ling; Chan, Pi-Tuan; Chang, Pi-Chen; Chiu, Huei-Ling; Sheen Hsiao, Shu-Tai; Chu, Hsin; Chou, Kuei-Ru
A better understanding of people with cognitive disorders improves performance on memory tasks through memory-focused interventions are needed. The purpose of this study was to assess the effect of memoryfocused interventions on cognitive disorders through a meta-analysis. Systematic review and meta-analysis. The online electronic databases PubMed, the Cochrane Library, Ovid-Medline, CINHAL, PsycINFO, Ageline, and Embase (up to May 2017) were used in this study. No language restriction was applied to the search. Objective memory (learning and memory function, immediate recall, delayed recall, and recognition) was the primary indicator and subjective memory performance, global cognitive function, and depression were the secondary indicators. The Hedges' g of change, subgroup analyses, and meta-regression were analyzed on the basis of the characteristics of people with cognitive disorders. A total of 27 studies (2177 participants, mean age=75.80) reporting RCTs were included in the meta-analysis. The results indicated a medium-to-large effect of memory-focused interventions on learning and memory function (Hedges' g=0.62) and subjective memory performance (Hedges' g=0.67), a small-to-medium effect on delayed recall and depression, and a small effect on immediate recall and global cognitive function (all pmemory function were more profound in the format of memory training, individual training, shorter treatment duration, and more than eight treatment sessions, and the effect size indicated the MMSE score was the most crucial indicator (β=-0.06, p=0.04). This is first comprehensive meta-analysis of special memory domains in people with cognitive disorders. The results revealed that memory-focused interventions effectively improved memory-related performance in people with cognitive disorders. An appropriately designed intervention can effectively improve memory function, reduce disability progression, and improve mood state in people with cognitive disorders
Jenkinson, Paul M; Taylor, Lauren; Laws, Keith R
An impairment of the ability to sense the physiological condition of the body - interoception - has long been proposed as central to the onset and maintenance of eating disorders. More recent attention to this topic has generally indicated the presence of interoceptive deficits in individuals with an eating disorder diagnosis; however, possible links with specific diagnosis, BMI, age, illness duration, depression, and alexithymia remain unclear from individual studies. This meta-analysis aimed to provide a necessary quantitative overview of self-reported interoceptive deficits in eating disorder populations, and the relationship between these deficits and the previously mentioned factors. Using a random effects model, our meta-analysis assessed the magnitude of differences in interoceptive abilities as measured using the Eating Disorder Inventory in 41 samples comparing people with eating disorders (n = 4308) and healthy controls (n = 3459). Follow-up and moderator analysis was conducted, using group comparisons and meta-regressions. We report a large pooled effect size of 1.62 for eating disorders with some variation between diagnostic groups. Further moderator analysis showed that BMI, age and alexithymia were significant predictors of overall effect size. This meta-analysis is the first to confirm that large interoceptive deficits occur in a variety of eating disorders and crucially, in those who have recovered. These deficits may be useful in identifying and distinguishing eating disorders. Future research needs to consider both objective and subjective measures of interoception across different types of eating disorders and may fruitfully examine interoception as a possible endophenotype and target for treatment. Copyright © 2018 Elsevier Inc. All rights reserved.
Atkin, Stephen L; Katsiki, Niki; Derosa, Giuseppe; Maffioli, Pamela; Sahebkar, Amirhossein
Curcumin is a naturally occurring polyphenol that has been suggested to improve several metabolic diseases. Leptin is an adipokine involved in metabolic status and appetite, with marked crosstalk with other systems. Available data suggest that curcumin may affect leptin levels; therefore, this meta-analysis was performed to evaluate this. A systematic review and meta-analysis were undertaken on all randomized controlled trials of curcumin studies that included the measurement of leptin. The search included PubMed-Medline, Scopus, ISI Web of Knowledge, and Google Scholar databases. Quantitative data synthesis was performed by using a random-effects model, with standardized mean difference and 95% confidence interval as summary statistics. A funnel plot, Begg's rank correlation, and Egger's weighted regression tests assessed the presence of publication bias. Four eligible articles comprising five treatment arms were selected for the meta-analysis. Meta-analysis showed a significant decrease in plasma leptin concentrations following curcumin treatment (standardized mean difference: -0.69, 95% confidence interval: -1.16, -0.23, p = 0.003; I 2 = 76.53%). There was no evidence of publication bias. This meta-analysis showed that curcumin supplementation is associated with a decrease in leptin levels that may be regarded as a potential mechanism for the metabolic effects of curcumin. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Caird, Jeff K; Johnston, Katherine A; Willness, Chelsea R; Asbridge, Mark
Three important and inter-related topics are addressed in this paper. First, the importance of meta-analysis and research synthesis methods to combine studies on traffic safety, in general, and on driver distraction, in particular, is briefly reviewed. Second, naturalistic, epidemiologic, and driving simulation studies on driver distraction are used to illustrate convergent and divergent results that have accumulated thus far in this domain of research. In particular, mobile phone conversation, passenger presence, and text messaging naturalistic studies use meta-analyses and research syntheses to illustrate important patterns of results that are in need of more in-depth study. Third, a number of driver distraction study limitations such as poorly defined dependent variables, lack of methodological detail, and omission of statistical information prevent the integration of many studies into meta-analyses. In addition, the overall quality of road safety studies suffers from these same limitations and suggestions for improvement are made to guide researchers and reviewers. Practical Applications. The use of research synthesis and meta-analysis provide comprehensive estimates of the impact of distractions on driving performance, which can be used to guide public policy and future research. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.
Determining whether social attention is reduced in Autism Spectrum Disorder (ASD) and what factors influence social attention is important to our theoretical understanding of developmental trajectories of ASD and to designing targeted interventions for ASD. This meta-analysis examines data from 38 articles that used eye-tracking methods to compare individuals with ASD and TD controls. In this paper, the impact of eight factors on the size of the effect for the difference in social attention between these two groups are evaluated: age, non-verbal IQ matching, verbal IQ matching, motion, social content, ecological validity, audio input and attention bids. Results show that individuals with ASD spend less time attending to social stimuli than typically developing (TD) controls, with a mean effect size of 0.55. Social attention in ASD was most impacted when stimuli had a high social content (showed more than one person). This meta-analysis provides an opportunity to survey the eye-tracking research on social attention in ASD and to outline potential future research directions, more specifically research of social attention in the context of stimuli with high social content. Copyright © 2015 Elsevier Ltd. All rights reserved.
Zhu, Zhaozhong; Anttila, Verneri; Smoller, Jordan W; Lee, Phil H
Advances in recent genome wide association studies (GWAS) suggest that pleiotropic effects on human complex traits are widespread. A number of classic and recent meta-analysis methods have been used to identify genetic loci with pleiotropic effects, but the overall performance of these methods is not well understood. In this work, we use extensive simulations and case studies of GWAS datasets to investigate the power and type-I error rates of ten meta-analysis methods. We specifically focus on three conditions commonly encountered in the studies of multiple traits: (1) extensive heterogeneity of genetic effects; (2) characterization of trait-specific association; and (3) inflated correlation of GWAS due to overlapping samples. Although the statistical power is highly variable under distinct study conditions, we found the superior power of several methods under diverse heterogeneity. In particular, classic fixed-effects model showed surprisingly good performance when a variant is associated with more than a half of study traits. As the number of traits with null effects increases, ASSET performed the best along with competitive specificity and sensitivity. With opposite directional effects, CPASSOC featured the first-rate power. However, caution is advised when using CPASSOC for studying genetically correlated traits with overlapping samples. We conclude with a discussion of unresolved issues and directions for future research.
Upala, Sikarin; Shahnawaz, Afeefa; Sanguankeo, Anawin
Psoriasis is a common chronic immune-mediated dermatological disease that increases the risk of cardiovascular disease. We conducted a systematic review and meta-analysis to evaluate the association between psoriasis and atrial fibrillation from prospective observational studies. A comprehensive search of the databases of the MEDLINE and EMBASE was performed from inception through November 2015. The inclusion criterion was the prospective observational study that assessed the risk of new-onset atrial fibrillation in adults with psoriasis. Outcome was the adjusted hazard ratio (HR) of atrial fibrillation comparison between patients with psoriasis and controls. Pooled HR and 95% confidence intervals (CI) were calculated using a random-effects model. The initial search yielded 176 articles. Fifteen articles underwent full-length review and data were extracted from 4 observational studies. Incidence of atrial fibrillation was ascertained by cardiologist-reviewed electrocardiograms. There was a significant increased risk of new-onset atrial fibrillation in patients with psoriasis compared to controls with a pooled HR 1.42 (95%CI 1.22-1.65). Our meta-analysis of prospective studies demonstrated that patients with psoriasis have increased risk of new-onset atrial fibrillation. Future interventional studies addressing the impact of psoriasis treatment and prevention of atrial fibrillation should be performed.
Full Text Available Hyperthyroidism affects about 0.2%-2.7% of all pregnancies, and is commonly managed with antithyroid drugs (ATDs. However, previous studies about the effects of ATDs on congenital anomalies are controversial. Therefore, the present meta-analysis was performed to explore the risk of congenital anomalies in children exposed to ATDs in-utero.Embase, Pubmed, Web of Knowledge, and BIOSIS Citation Index were searched to find out studies about congenital anomalies in children exposed to ATDs in-utero reported up to May 2014. The references cited by the retrieved articles were also searched. The relative risks (RRs and confidence intervals (CIs for the individual studies were pooled by fixed effects models, and heterogeneity was analyzed by chi-square and I2 tests.Eight studies met the inclusion criteria. Exposure to propylthiouracil (PTU, methimazole/carbimazole (MMI/CMZ, and PTU & MMI/CMZ was investigated in 7, 7 and 2 studies, respectively. The pooled RR was 1.20 (95%CI: 1.02-1.42, 1.64 (95%CI: 1.39-1.92, and 1.83 (95%CI: 1.30-2.56 for congenital anomalies after exposure to PTU, MMI/CMZ, and PTU & MMI/CMZ, respectively.The meta-analysis suggests that exposure to ATDs in-utero increases the risk of congenital anomalies. The use of ATDs in pregnancy should be limited when possible. Further research is needed to delineate the exact teratogenic risk for particular congenital anomaly.
Luo, Jiayou; Zeng, Rong; Feng, Na; Zhu, Na; Feng, Qi
Background Hyperthyroidism affects about 0.2%-2.7% of all pregnancies, and is commonly managed with antithyroid drugs (ATDs). However, previous studies about the effects of ATDs on congenital anomalies are controversial. Therefore, the present meta-analysis was performed to explore the risk of congenital anomalies in children exposed to ATDs in-utero. Methods Embase, Pubmed, Web of Knowledge, and BIOSIS Citation Index were searched to find out studies about congenital anomalies in children exposed to ATDs in-utero reported up to May 2014. The references cited by the retrieved articles were also searched. The relative risks (RRs) and confidence intervals (CIs) for the individual studies were pooled by fixed effects models, and heterogeneity was analyzed by chi-square and I 2 tests. Results Eight studies met the inclusion criteria. Exposure to propylthiouracil (PTU), methimazole/carbimazole (MMI/CMZ), and PTU & MMI/CMZ was investigated in 7, 7 and 2 studies, respectively. The pooled RR was 1.20 (95%CI: 1.02-1.42), 1.64 (95%CI: 1.39-1.92), and 1.83 (95%CI: 1.30-2.56) for congenital anomalies after exposure to PTU, MMI/CMZ, and PTU & MMI/CMZ, respectively. Conclusions The meta-analysis suggests that exposure to ATDs in-utero increases the risk of congenital anomalies. The use of ATDs in pregnancy should be limited when possible. Further research is needed to delineate the exact teratogenic risk for particular congenital anomaly. PMID:25974033
Gong, Pingyuan; Fan, Huiyong; Liu, Jinting; Yang, Xing; Zhang, Kejin; Zhou, Xiaolin
Oxytocin in the brain is related to empathy, which refers to the ability to understand and share others' internal states or responses. Previous studies have investigated the impact of OXTR rs53576, the most intensively examined polymorphism in the oxytocin receptor (OXTR) gene, on individual differences in empathy. However, these studies produced inconsistent results. In the current study, we reexamined the association of OXTR rs53576 with empathy in a relatively large population (N=1830) and also evaluated the association by a comprehensive meta-analysis (N=6631, 13 independent samples). The replication study indicated that OXTR rs53576 was indeed associated with individual differences in empathy. Individuals with a greater number of G alleles showed better empathic ability, particularly in fantasizing other's feelings and actions. The meta-analysis not only confirmed this association, but also indicated that the impact of this polymorphism was significant in both Europeans and Asians. These findings provide convincing evidence for the impact of OXTR rs53576 on empathy, highlighting the importance of OXTR gene in individuals' social cognition. Copyright © 2017. Published by Elsevier Ltd.
Fakhre, G Peter; Perdikis, Galen; Shaddix, Kyle K; Terkonda, Sarvam P; Waldorf, James C
The use of calcium hydroxylapatite (Radiesse, BioForm Medical, San Mateo, California) for cosmetic soft tissue augmentation has increased significantly in recent years. Only a handful of authors have reported patient satisfaction data. A meta-analysis of published data was performed using a 5-point scale for patient satisfaction to allow data comparison across studies. A patient-centric outcomes study was also performed at our institution, using a blinded questionnaire. Five usable studies were identified for meta-analysis. Patient satisfaction was 4.16 of 5 in 324 patients at 3 to 6 months and 4.15 in 86 patients at 1 year. In our institutional patient-centric outcomes study, the early satisfaction rate was 3.7 of 5. At 1 year the rate was only 2.3 of 5. Calcium hydroxylapatite remains a viable option for augmentation of facial soft tissue structures. However, this report shows that further, accurate, large population outcomes assessments are absolutely required.
Pennycook, Gordon; Ross, Robert M.; Koehler, Derek J.; Fugelsang, Jonathan A.
Individual differences in the mere willingness to think analytically has been shown to predict religious disbelief. Recently, however, it has been argued that analytic thinkers are not actually less religious; rather, the putative association may be a result of religiosity typically being measured after analytic thinking (an order effect). In light of this possibility, we report four studies in which a negative correlation between religious belief and performance on analytic thinking measures is found when religious belief is measured in a separate session. We also performed a meta-analysis on all previously published studies on the topic along with our four new studies (N = 15,078, k = 31), focusing specifically on the association between performance on the Cognitive Reflection Test (the most widely used individual difference measure of analytic thinking) and religious belief. This meta-analysis revealed an overall negative correlation (r) of -.18, 95% CI [-.21, -.16]. Although this correlation is modest, self-identified atheists (N = 133) scored 18.7% higher than religiously affiliated individuals (N = 597) on a composite measure of analytic thinking administered across our four new studies (d = .72). Our results indicate that the association between analytic thinking and religious disbelief is not caused by a simple order effect. There is good evidence that atheists and agnostics are more reflective than religious believers. PMID:27054566
Full Text Available There are disagreements among researchers about the association between vitamin D deficiency during pregnancy and preterm birth (PTB. Therefore, we conducted a meta-analysis of observational studies to evaluate this association. We performed a systematic literature search of PubMed, MEDLINE and the Cochrane Library through August 2015 with the following keywords: “vitamin D” or “cholecalciferol” or “25-hydroxyvitamin D” or “25(OHD” in combination with “premature birth” or “preterm birth” or “PTB” or “preterm delivery” or “PTD” or “prematurity”. Our meta-analysis of 10 studies included 10,098 participants and found that pregnant women with vitamin D deficiency (maternal serum 25 (OH D levels < 20 ng/mL experienced a significantly increased risk of PTB (odds ratio (OR = 1.29, 95% confidence intervals(CI: 1.16, 1.45 with low heterogeneity (I2 = 25%, p = 0.21. Sensitivity analysis showed that exclusion of any single study did not materially alter the overall combined effect. In the subgroup analyses, we found that heterogeneity was obvious in prospective cohort studies (I2 = 60%, p = 0.06. In conclusion, pregnant women with vitamin D deficiency during pregnancy have an increasing risk of PTB.
Full Text Available BACKGROUND: The associations between vitamin D receptor (VDR gene polymorphisms and breast cancer risk were comprehensively investigated to clarify issues that remain controversial. METHODOLOGY/PRINCIPAL FINDINGS: An electronic search was conducted of several databases, including PubMed, the Cochrane library, Web of Science, EMBASE, CBM and CNKI, for papers that describe the association between Fok1, poly-A repeat, Bsm1, Taq1 or Apa1 polymorphisms of the VDR gene and breast cancer risk. Summary odds ratios and 95% confidence intervals (CI were estimated based on a fixed-effect model (FEM or random-effect model (REM, depending on the absence or presence of significant heterogeneity. A total of 39 studies met the inclusion criteria. A meta-analysis of high-quality studies showed that the Fok1 polymorphism of the VDR gene was associated with an increased risk of breast cancer (ff vs. Ff+FF, OR: 1.09, 95%CI: 1.02 to 1.16, p = 0.007. No significant associations were observed between the other polymorphisms and breast cancer risk. No positive results were detected by pooling the results of all relevant studies. CONCLUSION: A meta-analysis of high-quality studies demonstrated that the Fok1 polymorphism of the VDR gene was closely associated with breast cancer risk.
Hoaglin, David C.; Hawkins, Neil; Jansen, Jeroen P.; Scott, David A.; Itzler, Robbin; Cappelleri, Joseph C.; Boersma, Cornelis; Thompson, David; Larholt, Kay M.; Diaz, Mireya; Barrett, Annabel
Evidence-based health care decision making requires comparison of all relevant competing interventions. In the absence of randomized controlled trials involving a direct comparison of all treatments of interest, indirect treatment comparisons and network meta-analysis provide useful evidence for
Delmas, Magali A.; Fischlein, Miriam; Asensio, Omar I.
Strategies that provide information about the environmental impact of activities are increasingly seen as effective to encourage conservation behavior. This article offers the most comprehensive meta-analysis of information based energy conservation experiments conducted to date. Based on evidence from 156 published field trials and 525,479 study subjects from 1975 to 2012, we quantify the energy savings from information based strategies. On average, individuals in the experiments reduced their electricity consumption by 7.4%. Our results also show that strategies providing individualized audits and consulting are comparatively more effective for conservation behavior than strategies that provide historical, peer comparison energy feedback. Interestingly, we find that pecuniary feedback and incentives lead to a relative increase in energy usage rather than induce conservation. We also find that the conservation effect diminishes with the rigor of the study, indicating potential methodological issues in the current literature. - Highlights: • We conduct a meta-analysis of information-based energy conservation experiments. • We analyze 156 published trials and 524,479 study subjects from 1975 to 2012. • On average, individuals in the experiments reduced electricity consumption by 7.4%. • Individualized feedback via audits and consulting results in the largest reductions. Pecuniary feedback and incentives lead to a relative increase in energy usage
Full Text Available Reduced dietary sodium intake (sodium reduction increases heart rate in some studies of animals and humans. As heart rate is independently associated with the development of heart failure and increased risk of premature death a potential increase in heart rate could be a harmful side-effect of sodium reduction. The purpose of the present meta-analysis was to investigate the effect of sodium reduction on heart rate. Relevant studies were retrieved from an updated pool of 176 randomized controlled trials (RCTs published in the period 1973–2014. 63 of the RCTs including 72 study populations reported data on heart rate. In a meta-analysis of these data sodium reduction increased heart rate with 1.65 beats per minute [95% CI: 1.19, 2.11], p < 0.00001, corresponding to 2.4% of the baseline heart rate. This effect was independent of baseline blood pressure. In conclusion sodium reduction increases heart rate by as much (2.4% as it decreases blood pressure (2.5%. This side-effect, which may cause harmful health effects, contributes to the need for a revision of the present dietary guidelines.
Kuss, Oliver; Hoyer, Annika; Solms, Alexander
There are still challenges when meta-analyzing data from studies on diagnostic accuracy. This is mainly due to the bivariate nature of the response where information on sensitivity and specificity must be summarized while accounting for their correlation within a single trial. In this paper, we propose a new statistical model for the meta-analysis for diagnostic accuracy studies. This model uses beta-binomial distributions for the marginal numbers of true positives and true negatives and links these margins by a bivariate copula distribution. The new model comes with all the features of the current standard model, a bivariate logistic regression model with random effects, but has the additional advantages of a closed likelihood function and a larger flexibility for the correlation structure of sensitivity and specificity. In a simulation study, which compares three copula models and two implementations of the standard model, the Plackett and the Gauss copula do rarely perform worse but frequently better than the standard model. We use an example from a meta-analysis to judge the diagnostic accuracy of telomerase (a urinary tumor marker) for the diagnosis of primary bladder cancer for illustration. Copyright © 2013 John Wiley & Sons, Ltd.
AlRyalat, Saif Aldeen
Gender similarities and differences have long been a matter of debate in almost all human research, especially upon reaching the discussion about brain functions. This large scale meta-analysis was performed on functional MRI studies. It included more than 700 active brain foci from more than 70 different experiments to study gender related similarities and differences in brain activation strategies for three of the main brain functions: Visual-spatial cognition, memory, and emotion. Areas that are significantly activated by both genders (i.e. core areas) for the tested brain function are mentioned, whereas those areas significantly activated exclusively in one gender are the gender specific areas. During visual-spatial cognition task, and in addition to the core areas, males significantly activated their left superior frontal gyrus, compared with left superior parietal lobule in females. For memory tasks, several different brain areas activated by each gender, but females significantly activated two areas from the limbic system during memory retrieval tasks. For emotional task, males tend to recruit their bilateral prefrontal regions, whereas females tend to recruit their bilateral amygdalae. This meta-analysis provides an overview based on functional MRI studies on how males and females use their brain.
Rocha, Renan Boeira; Dondossola, Eduardo Ronconi; Grande, Antônio José; Colonetti, Tamy; Ceretta, Luciane Bisognin; Passos, Ives C; Quevedo, Joao; da Rosa, Maria Inês
We performed a systematic review and meta-analysis to estimate brain-derived neurotrophic factor (BDNF) level in patients with major depressive disorder (MDD) after electroconvulsive therapy (ECT). A comprehensive search of the Cochrane Library, MEDLINE, LILACS, Grey literature, and EMBASE was performed for papers published from January 1990 to April 2016. The following key terms were searched: "major depressive disorder", "unipolar depression", "brain-derived neurotrophic factor", and "electroconvulsive therapy". A total of 252 citations were identified by the search strategy, and nine studies met the inclusion criteria of the meta-analysis. BDNF levels were increased among patients with MDD after ECT (P value = 0.006). The standardized mean difference was 0.56 (95% CI: 0.17-0.96). Additionally, we found significant heterogeneity between studies (I 2 = 73%). Our findings suggest a potential role of BDNF as a marker of treatment response after ECT in patients with MDD. Copyright © 2016 Elsevier Ltd. All rights reserved.
Full Text Available OBJECTIVE: A systematic review and meta-analysis of all available case-control studies on the relationship between onchocerciasis and epilepsy. Because age and level of onchocerciasis endemicity in the area of residence are major determinants for infection, an additional analysis was performed, restricted to studies achieving control of these confounding factors. DATA SOURCES: Medical databases, the "African Neurology Database, Institute of Neuroepidemiology and Tropical Neurology, Limoges," reference lists of relevant articles, commercial search engines, up to May 2012. METHODS: We searched for studies examining infection status with Onchocerca volvulus in persons with epilepsy (PWE and without epilepsy (PWOE providing data suitable for the calculation of pooled odds ratios (ORp and/or standardized mean differences (SMD using random-effects models. RESULTS: Eleven studies providing data of qualitative skin biopsies for diagnosis of onchocerciasis were identified. Combined analysis on the total sample of 876 PWE and 4712 PWOE resulted in an ORp of 2.49 (95% confidence interval (95%CI: 1.61-3.86, p<0.001. When this analysis was restricted to those studies achieving control for age, residence and sex (367 PWE, 624 PWOE, an ORp of 1.29 (95% CI: 0.93-1.79; p = 0.139 was found. Presence of nodules for diagnosis of onchocerciasis was analyzed in four studies (225 PWE, 189 PWOE; ORp 1.74; 95%CI: 0.94-3.20; p<0.076, including two studies of the restricted analysis (106 PWE, 106 PWOE; ORp 2.81; 95%CI: 1.57-5.00; p<0.001. One study examined quantitative microfilariae counts in patients without preceding microfilaricidal treatment and demonstrated significantly higher counts in PWE than in PWOE. INTERPRETATION: Our results strengthen the hypothesis that, in onchocerciasis foci, epilepsy and infection with O. volvulus are associated. Analysis of indicators giving information on infection intensity, namely nodule palpation and quantitative microfilaria
Full Text Available Notwithstanding some discrepancy between results from neuroimaging studies of symptom provocation in posttraumatic stress disorder (PTSD, there is broad agreement as to the neural circuit underlying this disorder. It is thought to be characterized by an exaggerated amygdalar and decreased medial prefrontal activation to which the elevated anxiety state and concomitant inadequate emotional regulation are attributed. However, the proposed circuit falls short of accounting for the main symptom, unique among anxiety disorders to PTSD, namely, reexperiencing the precipitating event in the form of recurrent, distressing images and recollections. Owing to the technical demands, neuroimaging studies are usually carried out with small sample sizes. A meta-analysis of their findings is more likely to cast light on the involved cortical areas. Coordinate-based meta-analyses employing ES-SDM (Effect Size Signed Differential Mapping were carried out on 19 studies with 274 PTSD patients. Thirteen of the studies included 145 trauma-exposed control participants. Comparisons between reactions to trauma-related stimuli and a control condition and group comparison of reactions to the trauma-related stimuli were submitted to meta-analysis. Compared to controls and the neutral condition, PTSD patients showed significant activation of the mid-line retrosplenial cortex and precuneus in response to trauma-related stimuli. These midline areas have been implicated in self-referential processing and salient autobiographical memory. PTSD patients also evidenced hyperactivation of the pregenual/anterior cingulate gyrus and bilateral amygdala to trauma-relevant, compared to neutral, stimuli. Patients showed significantly less activation than controls in sensory association areas such as the bilateral temporal gyri and extrastriate area which may indicate that the patients' attention was diverted from the presented stimuli by being focused on the elicited trauma memory. Being
Mattmann, M.; Logar, I.; Brouwer, R.
This paper presents a meta-analysis of existing research related to the economic valuation of the external effects of hydropower. A database consisting of 81 observations derived from 29 studies valuing the non-market impacts of hydropower electricity generation is constructed with the main aim to
Cassar, Samantha; Misso, Marie L; Hopkins, William G; Shaw, Christopher S; Teede, Helena J; Stepto, Nigel K
What is the degree of intrinsic insulin resistance (IR) in women with polycystic ovary syndrome (PCOS) and the relative contribution of BMI to overall IR based on meta-analysis of gold standard insulin clamp studies? We report an inherent reduction (-27%) of insulin sensitivity (IS) in PCOS patients, which was independent of BMI. PCOS is prevalent, complex and underpinned by IR but controversies surround the degree of intrinsic IR in PCOS, the effect of BMI and the impact of the different diagnostic criteria (NIH versus Rotterdam) in PCOS. A systematic review and meta-analysis of Medline and All EBM databases was undertaken of studies published up to 30 May 2015. Studies were included if premenopausal women diagnosed with PCOS were compared with a control group for IS, measured by the gold standard euglycaemic-hyperinsulinaemic clamp. The systematic review adheres to the principles of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Meta-analyses were performed using mixed modelling and magnitude-based inferences expressed as mean effect ±99% CI. We inferred the effect was small, moderate or large relative to a smallest important change of -3.7% or 3.8% derived by standardisation. Effects were deemed unclear when the CI overlapped smallest important positive and negative values. Effects were qualified with probabilities reflecting uncertainty in the magnitude of the true value (likely, 75-95%; very likely, 95-99.5%; most likely, >99.5%). A total of 4881 articles were returned from the search. Of these, 28 articles were included in the meta-analysis. Overall IS was lower in women with PCOS compared with controls (mean effect -27%, 99% CI ±6%; large, most likely lower). A higher BMI exacerbated the reduction in IS by -15% (±8%; moderate, most likely lower) in PCOS compared with control women. There was no clear difference in IS between women diagnosed by the original National Institutes of Health (NIH) criteria alone
Ng, Maggie C Y; Shriner, Daniel; Chen, Brian H
. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA) Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs......) association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications...... for linkage disequilibrium, enabling fine mapping of causal variants in trans-ethnic meta-analysis studies....
Ingason, Andrés; Giegling, Ina; Cichon, Sven
The Abelson helper integration site 1 (AHI1) gene locus on chromosome 6q23 is among a group of candidate loci for schizophrenia susceptibility that were initially identified by linkage followed by linkage disequilibrium mapping, and subsequent replication of the association in an independent sample....... Here, we present results of a replication study of AHI1 locus markers, previously implicated in schizophrenia, in a large European sample (in total 3907 affected and 7429 controls). Furthermore, we perform a meta-analysis of the implicated markers in 4496 affected and 18,920 controls. Both...... as the neighbouring phosphodiesterase 7B (PDE7B)-may be considered candidates for involvement in the genetic aetiology of schizophrenia....
Rafiq, Shamaila; Jeppesen, Per Bendix
and meta-analysis of cross sectional and longitudinal studies. We searched Pubmed, Medline and Embase, all through June 2017. The studies were selected to determine the effect of vitamin D on the parameters of glucose metabolism in diabetic and non-diabetic subjects. Correlation coefﬁcients from all...... studies were pooled in a random effects meta-analysis. The risk of bias was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. We found signiﬁcant inverse relationship of vitamin D status with glycemic level in both diabetic (r = −0.223, 95% CI = −0.184 to −0.......261, p = 0.000) and non-diabetic (r = −0.073, 95% CI =−0.052 to−0.093, p = 0.000) subjects. This meta-analysis concludes that hypovitaminosis D isassociatedwithincreasedriskofhyperglycemiabothindiabeticandnon-diabeticsubjects. Afuture...
Raza, Mushahid; Elkhodair, Samer; Zaheer, Asif; Yousaf, Sohail
A true gold standard to rule out a significant cervical spine injury in subset of blunt trauma patients with altered sensorium is still to be agreed upon. The objective of this study is to determine whether in obtunded adult patients with blunt trauma, a clinically significant injury to the cervical spine be ruled out on the basis of a normal multidetector cervical spine computed tomography. Comprehensive database search was conducted to include all the prospective and retrospective studies on blunt trauma patients with altered sensorium undergoing cervical spine multidetector CT scan as core imaging modality to "clear" the cervical spine. The studies used two main gold standards, magnetic resonance imaging of the cervical spine and/or prolonged clinical follow-up. The data was extracted to report true positive, true negatives, false positives and false negatives. Meta-analysis of sensitivity, specificity, negative and positive predictive values was performed using Meta Analyst Beta 3.13 software. We also performed a retrospective investigation comparing a robust clinical follow-up and/or cervical spine MR findings in 53 obtunded blunt trauma patients, who previously had undergone a normal multidetector CT scan of the cervical spine reported by a radiologist. A total of 10 studies involving 1850 obtunded blunt trauma patients with initial cervical spine CT scan reported as normal were included in the final meta-analysis. The cumulative negative predictive value and specificity of cervical spine CT of the ten studies was 99.7% (99.4-99.9%, 95% confidence interval). The positive predictive value and sensitivity was 93.7% (84.0-97.7%, 95% confidence interval). In the retrospective review of our obtunded blunt trauma patients, none was later diagnosed to have significant cervical spine injury that required a change in clinical management. In a blunt trauma patient with altered sensorium, a normal cervical spine CT scan is conclusive to safely rule out a clinically
Rubio-Rivas, Manuel; Moreno, Rafael; Corbella, Xavier
The etiology of systemic sclerosis (SSc) remains unknown; however, several occupational and environmental factors have been implicated. Our objective was to perform a meta-analysis of all studies published on SSc associated with occupational and environmental exposure. The review was undertaken by means of MEDLINE and SCOPUS from 1960 to 2014 and using the terms: "systemic," "scleroderma," or "systemic sclerosis/chemically induced" [MesH]. The Newcastle-Ottawa Scale was used for the qualifying assessment. The inverse variance-weighted method was performed. The meta-analysis of silica exposure included 15 case-control studies [overall OR 2.81 (95%CI 1.86-4.23; p < 0.001)] and 4 cohort studies [overall RR 17.52 (95%CI 5.98-51.37; p < 0.001)]; the meta-analysis of solvents exposure included 13 case-control studies (overall OR 2.00 [95%CI 1.32-3.02; p = 0.001); the meta-analysis of breast implants exposure included 4 case-control studies (overall OR 1.68 (95%CI 1.65-1.71; p < 0.001)) and 6 cohort studies (overall RR 2.13 (95%CI 0.86-5.27; p = 0.10)); the meta-analysis of epoxy resins exposure included 4 case-control studies (overall OR 2.97 (95%CI 2.31-3.83; p < 0.001)), the meta-analysis of pesticides exposure included 3 case-control studies (overall OR 1.02 (95%CI 0.78-1.32; p = 0.90)) and, finally, the meta-analysis of welding fumes exposure included 4 studies (overall OR 1.29 (95%CI 0.44-3.74; p = 0.64)). Not enough studies citing risks related to hair dyes have been published to perform an accurate meta-analysis. Silica and solvents were the two most likely substances related to the pathogenesis of SSc. While silica is involved in particular jobs, solvents are widespread and more people are at risk of having incidental contact with them.
This paper is a corrigendum to a previously published paper where errors were detected. The errors have been corrected in this paper. The paper is otherwise identical to the previously published paper. A systematic review and meta-analysis of studies that have assessed the risk of accident associated with the use of drugs when driving is presented. The meta-analysis included 66 studies containing a total of 264 estimates of the effects on accident risk of using illicit or prescribed drugs when driving. Summary estimates of the odds ratio of accident involvement are presented for amphetamines, analgesics, anti-asthmatics, anti-depressives, anti-histamines, benzodiazepines, cannabis, cocaine, opiates, penicillin and zopiclone (a sleeping pill). For most of the drugs, small or moderate increases in accident risk associated with the use of the drugs were found. Information about whether the drugs were actually used while driving and about the doses used was often imprecise. Most studies that have evaluated the presence of a dose-response relationship between the dose of drugs taken and the effects on accident risk confirm the existence of a dose-response relationship. Use of drugs while driving tends to have a larger effect on the risk of fatal and serious injury accidents than on the risk of less serious accidents (usually property-damage-only accidents). The quality of the studies that have assessed risk varied greatly. There was a tendency for the estimated effects of drug use on accident risk to be smaller in well-controlled studies than in poorly controlled studies. Evidence of publication bias was found for some drugs. The associations found cannot be interpreted as causal relationships, principally because most studies do not control very well for potentially confounding factors. Copyright © 2012 Elsevier Ltd. All rights reserved.
Zhu, Changtai; Jiang, Ting; Cao, Hao; Sun, Wenguang; Chen, Zhong; Liu, Jinming
The meta-analysis is regarded as an important evidence for making scientific decision. The database of ISI Web of Science collected a great number of high quality literatures including meta-analysis literatures. However, it is significant to understand the general characteristics of meta-analysis literatures to outline the perspective of meta-analysis. In this present study, we summarized and clarified some features on these literatures in the database of ISI Web of Science. We retrieved the meta-analysis literatures in the database of ISI Web of Science including SCI-E, SSCI, A&HCI, CPCI-S, CPCI-SSH, CCR-E, and IC. The annual growth rate, literature category, language, funding, index citation, agencies and countries/territories of the meta-analysis literatures were analyzed, respectively. A total of 95,719 records, which account for 0.38% (99% CI: 0.38%-0.39%) of all literatures, were found in the database. From 1997 to 2012, the annual growth rate of meta-analysis literatures was 18.18%. The literatures involved in many categories, languages, fundings, citations, publication agencies, and countries/territories. Interestingly, the index citation frequencies of the meta-analysis were significantly higher than that of other type literatures such as multi-centre study, randomize controlled trial, cohort study, case control study, and cases report (Panalysis has been becoming more and more prominent in recent years. In future, in order to promote the validity of meta-analysis, the CONSORT and PRISMA standard should be continuously popularized in the field of evidence-based medicine.
Ferraz Cavalcanti, Paulo Ernando; Sá, Michel Pompeu Barros Oliveira; Santos, Cecília Andrade; Esmeraldo, Isaac Melo; de Escobar, Rodrigo Renda; de Menezes, Alexandre Motta; de Azevedo, Orlando Morais; de Vasconcelos Silva, Frederico Pires; Lins, Ricardo Felipe de Albuquerque; Lima, Ricardo de Carvalho
Because the real benefit of pulmonary valve replacement (PVR) in patients with repaired tetralogy of Fallot who develop pulmonary insufficiency remains unclear, it is necessary to analyze the evidence published around the world. We performed a systematic review of studies that reported data about the effect of PVR in patients with repaired tetralogy of Fallot that developed pulmonary insufficiency, until December 2012. The variables chosen to represent the benefit were both right ventricular (RV) and left ventricular measures, QRS duration, and functional class. The principal summary measures were difference in means with 95% confidence interval and p values (considered statistically significant when p regression were completed with the software Comprehensive Meta-Analysis (version 2, Biostat, Inc., Englewood, New Jersey). Forty-eight studies involving 3,118 patients met the eligibility criteria. The pooled 30-day mortality was 0.87% (47 studies; 27 of 3,100 patients); the pooled 5-year mortality was 2.2% (24 studies; 49 of 2,231 patients); the pooled 5-year re-PVR was 4.9% (15 studies; 88 of 1,798 patients). The results of this meta-analysis demonstrate that after PVR: 1) the RV experiences improvement of its volumes and function; 2) the left ventricle experiences improvement of its function; 3) QRS duration decreases; 4) symptoms improve; 5) pre-operative RV geometry modulates the effect of PVR; and 6) there is important heterogeneity of the effects among the studies, and few publication biases. In conclusion, PVR seems to be a positive approach in the analyzed scenario. Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Background-Although experimental data suggest that statin therapy may improve neurological outcome after acute cerebral ischemia, the results from clinical studies are conflicting. We performed a systematic review and meta-analysis investigating the relationship between statin therapy and outcome after ischemic stroke. METHODS: The primary analysis investigated statin therapy at stroke onset (prestroke statin use) and good functional outcome (modified Rankin score 0 to 2) and death. Secondary analyses included the following: (1) acute poststroke statin therapy (≤72 hours after stroke), and (2) thrombolysis-treated patients. RESULTS: The primary analysis included 113 148 subjects (27 studies). Among observational studies, statin treatment at stroke onset was associated with good functional outcome at 90 days (pooled odds ratio [OR], 1.41; 95% confidence interval [CI], 1.29-1.56; P<0.001), but not 1 year (OR, 1.12; 95% CI, 0.9-1.4; P=0.31), and with reduced fatality at 90 days (pooled OR, 0.71; 95% CI, 0.62-0.82; P<0.001) and 1 year (OR, 0.80; 95% CI, 0.67-0.95; P=0.01). In the single randomized controlled trial reporting 90-day functional outcome, statin treatment was associated with good outcome (OR, 1.5; 95% CI, 1.0-2.24; P=0.05). No reduction in fatality was observed on meta-analysis of data from 3 randomized controlled trials (P=0.9). In studies of thrombolysis-treated patients, an association between statins and increased fatality at 90 days was observed (pooled OR, 1.25; 95% CI, 1.02-1.52; P=0.03, 3 studies, 4339 patients). However, this association was no longer present after adjusting for age and stroke severity in the largest study (adjusted OR, 1.14; 95% CI, 0.90-1.44; 4012 patients). CONCLUSIONS: In the largest meta-analysis to date, statin therapy at stroke onset was associated with improved outcome, a finding not observed in studies restricted to thrombolysis-treated patients. Randomized trials of statin therapy in acute ischemic stroke are needed.
Løkkegaard, Annemette; Herz, Damian M; Haagensen, Brian Numelin
Dystonia is characterized by sustained or intermittent muscle contractions causing abnormal, often repetitive, movements or postures. Functional neuroimaging studies have yielded abnormal task-related sensorimotor activation in dystonia, but the results appear to be rather variable across studies....... Further, study size was usually small including different types of dystonia. Here we performed an activation likelihood estimation (ALE) meta-analysis of functional neuroimaging studies in patients with primary dystonia to test for convergence of dystonia-related alterations in task-related activity...... postcentral gyrus, right superior temporal gyrus and dorsal midbrain. Apart from the midbrain cluster, all between-group differences in task-related activity were retrieved in a sub-analysis including only the 14 studies on patients with focal dystonia. For focal dystonia, an additional cluster of increased...
Malerba, Stefano; Turati, Federica; Galeone, Carlotta; Pelucchi, Claudio; Verga, Federica; La Vecchia, Carlo; Tavani, Alessandra
Several prospective studies considered the relation between coffee consumption and mortality. Most studies, however, were underpowered to detect an association, since they included relatively few deaths. To obtain quantitative overall estimates, we combined all published data from prospective studies on the relation of coffee with mortality for all causes, all cancers, cardiovascular disease (CVD), coronary/ischemic heart disease (CHD/IHD) and stroke. A bibliography search, updated to January 2013, was carried out in PubMed and Embase to identify prospective observational studies providing quantitative estimates on mortality from all causes, cancer, CVD, CHD/IHD or stroke in relation to coffee consumption. A systematic review and meta-analysis was conducted to estimate overall relative risks (RR) and 95 % confidence intervals (CI) using random-effects models. The pooled RRs of all cause mortality for the study-specific highest versus low (≤1 cup/day) coffee drinking categories were 0.88 (95 % CI 0.84-0.93) based on all the 23 studies, and 0.87 (95 % CI 0.82-0.93) for the 19 smoking adjusting studies. The combined RRs for CVD mortality were 0.89 (95 % CI 0.77-1.02, 17 smoking adjusting studies) for the highest versus low drinking and 0.98 (95 % CI 0.95-1.00, 16 studies) for the increment of 1 cup/day. Compared with low drinking, the RRs for the highest consumption of coffee were 0.95 (95 % CI 0.78-1.15, 12 smoking adjusting studies) for CHD/IHD, 0.95 (95 % CI 0.70-1.29, 6 studies) for stroke, and 1.03 (95 % CI 0.97-1.10, 10 studies) for all cancers. This meta-analysis provides quantitative evidence that coffee intake is inversely related to all cause and, probably, CVD mortality.
Full Text Available Qixing Mao,1–3,* Mantang Qiu,1–3,* Gaochao Dong,3 Wenjie Xia,1–3 Shuai Zhang,1,3 Youtao Xu,1,3 Jie Wang,3 Yin Rong,1,3 Lin Xu,1,3 Feng Jiang1,3 1Department of Thoracic Surgery, Nanjing Medical University Affiliated Cancer Institute of Jiangsu Province, 2Fourth Clinical College of Nanjing Medical University, 3Jiangsu Key Laboratory of Molecular and Translational Cancer Research, Nanjing, People’s Republic of China *These authors contributed equally to this work Abstract: The association between polymorphic CAG repeats in the androgen receptor gene in women and breast cancer susceptibility has been studied extensively. However, the conclusions regarding this relationship remain conflicting. The purpose of this meta-analysis was to identify whether androgen receptor CAG repeat lengths were related to breast cancer susceptibility. The MEDLINE, PubMed, and EMBASE databases were searched through to December 2014 to identify eligible studies. Data and study quality were rigorously assessed by two investigators according to the Newcastle-Ottawa Quality Assessment Scale. The publication bias was assessed by the Begg’s test. Seventeen eligible studies were included in this meta-analysis. The overall analysis suggested no association between CAG polymorphisms and breast cancer risk (odds ratio [OR] 1.031, 95% confidence interval [CI] 0.855–1.245. However, in the subgroup analysis, we observed that long CAG repeats significantly increased the risk of breast cancer in the Caucasian population (OR 1.447, 95% CI 1.089–1.992. Additionally, the risk was significantly increased in Caucasian women carrying two alleles with CAG repeats ≥22 units compared with those with two shorter alleles (OR 1.315, 95% CI 1.014–1.707. These findings suggest that long CAG repeats increase the risk of breast cancer in Caucasian women. However, larger scale case-control studies are needed to validate our results. Keywords: androgen, CAG repeat polymorphism, women
Du, Hong-Bing; Bin, Kai-Yun; Liu, Wen-Hong; Yang, Feng-Sheng
Epidemiology studies suggested that shift work or night work may be linked to prostate cancer (PCa); the relationship, however, remains controversy. PubMed, ScienceDirect, and Embase (Ovid) databases were searched before (started from the building of the databases) February 4, 2017 for eligible cohort studies. We pooled the evidence included by a random- or fixed-effect model, according to the heterogeneity. A predefined subgroup analysis was conducted to see the potential discrepancy between groups. Sensitivity analysis was used to test whether our results were stale. Nine cohort studies were eligible for meta-analysis with 2,570,790 male subjects. Our meta-analysis showed that, under the fixed-effect model, the pooled relevant risk (RR) of PCa was 1.05 (95% confidence interval [CI]: 1.00, 1.11; P = .06; I = 24.00%) for men who had ever engaged in night shift work; and under the random-effect model, the pooled RR was 1.08 (0.99, 1.17; P = .08; I = 24.00%). Subgroup analysis showed the RR of PCa among males in western countries was 1.05 (95% CI: 0.99, 1.11; P = .09; I = 0.00%), while among Asian countries it was 2.45 (95% CI: 1.19, 5.04; P = .02; I = 0.00%); and the RR was 1.04 (95% CI: 0.95, 1.14; P = .40; I = 29.20%) for the high-quality group compared with 1.21 (95% CI: 1.03, 1.41; P = .02; I = 0.00%) for the moderate/low-quality group. Sensitivity analysis showed robust results. Based on the current evidence of cohort studies, we found no obvious association between night shift work and PCa. However, our subgroup analysis suggests that night shift work may increase the risk of PCa in Asian men. Some evidence of a small study effect was observed in this meta-analysis.
Deng, Yuqin; Wang, Xiaochun; Wang, Yan; Zhou, Chenglin
Interference resolution refers to cognitive control processes enabling one to focus on task-related information while filtering out unrelated information. But the exact neural areas, which underlie a specific cognitive task on interference resolution, are still equivocal. The multi-source interference task (MSIT), as a particular cognitive task, is a well-established experimental paradigm used to evaluate interference resolution. Studies combining the MSIT with functional magnetic resonance imaging (fMRI) have shown that the MSIT evokes the dorsal anterior cingulate cortex (dACC) and cingulate-frontal-parietal cognitive-attentional networks. However, these brain areas have not been evaluated quantitatively and these findings have not been replicated. In the current study, we firstly report a voxel-based meta-analysis of functional brain activation associated with the MSIT so as to identify the localization of interference resolution in such a specific cognitive task. Articles on MSIT-related fMRI published between 2003 and July 2017 were eligible. The electronic databases searched included PubMed, Web of Knowledge, and Google Scholar. Differential BOLD activation patterns between the incongruent and congruent condition were meta-analyzed in anisotropic effect-size signed differential mapping software. Robustness meta-analysis indicated that two significant activation clusters were shown to have reliable functional activity in comparisons between incongruent and congruent conditions. The first reliable activation cluster, which included the dACC, medial prefrontal cortex, supplementary motor area, replicated the previous MSIT-related fMRI study results. Furthermore, we found another reliable activation cluster comprising areas of the right insula, right inferior frontal gyrus, and right lenticular nucleus-putamen, which were not typically discussed in previous MSIT-related fMRI studies. The current meta-analysis study presents the reliable brain activation patterns
Costa, João; Lunet, Nuno; Santos, Catarina; Santos, João; Vaz-Carneiro, António
Several studies conducted worldwide report an inverse association between caffeine/coffee consumption and the risk of developing Parkinson's disease (PD). However, heterogeneity and conflicting results between studies preclude a correct estimation of the strength of this association. We conducted a systematic review and meta-analysis of published epidemiological studies to better estimate the effect of caffeine exposure on the incidence of PD. Data sources searched included Medline, LILACS, Scopus, Web of Science and reference lists, up to September 2009. Cohort, case-control and cross-sectional studies were included. Three independent reviewers selected the studies and extracted the data on to standardized forms. Twenty-six studies were included: 7 cohort, 2 nested case-control, 16 case-control, and 1 cross-sectional study. Quantitative data synthesis of the most precise estimates from each study was accomplished through random effects meta-analysis. Heterogeneity was quantified using the I2 statistic. The summary RR for the association between caffeine intake and PD was 0.75 [[95% Confidence Interval (95%CI): 0.68-0.82], with low to moderate heterogeneity (I2= 28.8%). Publication bias for case-control/cross-sectional studies may exist (Egger's test, p=0.053). When considering only the cohort studies, the RR was 0.80 (95%CI: 0.71-90; I2=8.1%). The negative association was weaker when only women were considered (RR=0.86, 95%CI: 0.73-1.02; I2=12.9%). A linear relation was observed between levels of exposure to caffeine and the RR estimates: RR of 0.76 (95%CI: 0.72-0.80; I2= 35.1%) per 300 mg increase in caffeine intake. This study confirm an inverse association between caffeine intake and the risk of PD, which can hardly by explained by bias or uncontrolled confounding.
Feng, Mei; Zhu, Jing; Liang, Liqun; Zeng, Ni; Wu, Yanqiu; Wan, Chun; Shen, Yongchun; Wen, Fuqiang
Pleural effusion is one of the most common complications of lung adenocarcinoma and is diagnostically challenging. This study aimed to investigate the diagnostic performance of carcinoembryonic antigen (CEA), cytokeratin fragment (CYFRA) 21-1, and cancer antigen (CA) 19-9 for lung adenocarcinoma-associated malignant pleural effusion (MPE) through a validation study and meta-analysis. Pleural effusion samples were collected from 81 lung adenocarcinoma-associated MPEs and 96 benign pleural effusions. CEA, CYFRA 21-1, and CA19-9 were measured by electrochemiluminescence immunoassay. The capacity of tumor markers was assessed with receiver operating characteristic curve analyses and the area under the curve (AUC) was calculated. Standard methods for meta-analysis of diagnostic studies were used to summarize the diagnostic performance of CEA, CYFRA 21-1, and CA19-9 for lung adenocarcinoma-associated MPE. The pleural levels of CEA, CYFRA 21-1, and CA19-9 were significantly increased in lung adenocarcinoma-associated MPE compared to benign pleural effusion. The cut-off points for CEA, CYFRA 21-1, and CA19-9 were optimally set at 4.55 ng/ml, 43.10 μg/ml, and 12.89 U/ml, and corresponding AUCs were 0.93, 0.85, and 0.81, respectively. The combination of CEA, CYFRA 21-1, and CA19-9 increased the sensitivity to 95.06%, with an AUC of 0.95. Eight studies were included in this meta-analysis. CEA showed the best diagnostic performance with pooled sensitivity, specificity, positive/negative likelihood ratio, and diagnostic odds ratio of 0.75, 0.96, 16.01, 0.23, and 81.49, respectively. The AUC was 0.93. CEA, CYFRA 21-1, and CA19-9 play a role in the diagnosis of lung adenocarcinoma-associated MPE. The combination of these tumor markers increases the diagnostic accuracy.
Full Text Available Background: Non-celiac gluten sensitivity (NCGS is a clinical entity characterized by intestinal and/or extra-intestinal symptoms related to the ingestion of gluten in individuals that are not affected by either celiac disease (CD or wheat allergy (WA. Since we do not have specific biomarkers for NCGS, the diagnosis is based on the evidence of a clear relationship between the ingestion of gluten (re-challenge and clinical symptoms, after a remission during the gluten-free diet (GFD. Several re-challenge studies have been published so far to evaluate the real prevalence of NCGS, reporting conflicting results. In the present article, we provide a systematic review with meta-analysis of the existing literature on re-challenge studies to evaluate prevalence figures of NCGS after re-challenge procedures.Methods: All clinical trials performing a gluten re-challenge with or without a placebo control in patients with a suspected diagnosis of NCGS were included. Search results were limited to studies published in English language. No publication date or publication status restrictions were imposed.Results: Eleven studies were included in the meta-analysis. There was a considerable heterogeneity related to different sample size, type, and amount of gluten administered, duration of challenge and different type of placebo. The overall pooled percentage of patients with a diagnosis of NCGS relapsing after a gluten challenge was 30%, ranging between 7 and 77%. The meta-analysis showed a not significant relative risk (RR of relapse after gluten challenge as compared to placebo (RR = 0.4; 95% CI = −0.15–0.9; p = 0.16. The overall pooled percentage of patients with a diagnosis of NCGS relapsing after a gluten challenge performed according to the recent Salerno criteria was significantly higher as compared to the percentage of patients relapsing after placebo (40 vs. 24%; p = 0.003, with a significant RR of relapse after gluten challenge as compared to
Full Text Available Previous studies reported the associations between the ATP-binding cassette sub-family B member 1 (ABCB1, also known as MDR1 polymorphisms and their haplotypes with risk of response to antiepileptic drugs in epilepsy, however, the results were inconclusive.The Pubmed, Embase, Web of Science, CNKI and Chinese Biomedicine databases were searched up to July 15, 2014. Pooled odds ratios (ORs and 95% confidence intervals (CIs were calculated using a fixed-effects or random-effects model based on heterogeneity tests. Meta-regression and Galbraith plot analysis were carried out to explore the possible heterogeneity.A total of 57 studies involving 12407 patients (6083 drug-resistant and 6324 drug-responsive patients with epilepsy were included in the pooled-analysis. For all three polymorphisms (C3435T, G2677T/A, and C1236T, we observed a wide spectrum of minor allele frequencies across different ethnicities. A significantly decreased risk of AEDs resistance was observed in Caucasian patients with T allele of C3435T variant, which was still significant after adjusted by multiple testing corrections (T vs C: OR=0.83, 95%CI=0.71-0.96, p=0.01. However, no significant association was observed between the other two variants and AEDs resistance. Of their haplotypes in ABCB1 gene (all studies were in Indians and Asians, no significant association was observed with AEDs resistance. Moreover, sensitivity and Cumulative analysis showed that the results of this meta-analysis were stable.In summary, this meta-analysis demonstrated that effect of C3435T variant on risk of AEDs resistance was ethnicity-dependent, which was significant in Caucasians. Additionally, further studies in different ethnic groups are warranted to clarify possible roles of haplotypes in ABCB1 gene in AEDs resistance, especially in Caucasians.
Xu, Ping; Luo, Hong; Huang, Guang-Lei; Yin, Xin-Hai; Luo, Si-Yang; Song, Ju-Kun
Many observational studies have found that exposure to dental X-rays is associated with the risk of development of meningioma. However, these findings are inconsistent. We conducted a meta-analysis to assess the relationship between exposure to dental X-rays and the risk of development of meningioma. The PubMed and EMBASE databases were searched to identify eligible studies. Summary odds ratio (OR) estimates and 95% confidence intervals (95% CIs) were used to compute the risk of meningioma development according to heterogeneity. Subgroup and sensitivity analyses were performed to further explore the potential heterogeneity. Finally, publication bias was assessed. Seven case-control studies involving 6,174 patients and 19,459 controls were included in the meta-analysis. Neither exposure to dental X-rays nor performance of full-mouth panorex X-rays was associated with an increased risk of development of meningioma (overall: OR, 0.97; 95% CI, 0.70-1.32; dental X-rays: OR, 1.05; 95% CI, 0.89-1.25; panorex X-rays: OR, 1.01; 95% CI, 0.76-1.34). However, exposure to bitewing X-rays was associated with a slightly increased risk of development of meningioma (OR, 1.73; 95% CI, 1.28-2.34). Similar results were obtained in the subgroup and sensitivity analyses. Little evidence of publication bias was observed. Based on the currently limited data, there is no association between exposure to dental X-rays and the risk of development of meningioma. However, these results should be cautiously interpreted because of the heterogeneity among studies. Additional large, high-quality clinical trials are needed to evaluate the association between exposure to dental X-rays and the risk of development of meningioma.
Fabrizi, F; Dixit, V; Martin, P; Messa, P
It is well known that the seroconversion rate of patients following hepatitis B virus (HBV) vaccination is lower in uraemic than healthy subjects. A variety of inherited or acquired factors have been implicated in this diminished response, and the high prevalence of hepatitis C virus (HCV) infection among patients on maintenance dialysis has been suggested to play a role. However, the impact of HCV on the immune response to HB vaccine in patients receiving long-term dialysis is not entirely understood. Here, we evaluate the influence of HCV infection on the immunological response to HBV vaccine in dialysis population by performing a systematic review of the literature with a meta-analysis of clinical studies.We used the random-effects model of DerSimonian and Laird with heterogeneity and sensitivity analyses. The end-point of interest was the rate of patients showing seroprotective anti-hepatitis B titres at completion of HBV vaccine schedule among HCV-positive versus HCV-negative patients on chronic dialysis. We identified eight studies involving 520 unique patients on long-term dialysis. Aggregation of study results did not show a significant decrease in response rates among HCV-infected versus noninfected patients [pooled odds ratio = 0.621 (95% CI, 0.285; 1.353)]. The P-value was 0.007 for our test of study heterogeneity. Stratified analysis in various subgroups of interest did not meaningfully change our results. Our meta-analysis showed no association between immunological response to hepatitis B vaccine and HCV infection in individuals on long-term dialysis. These results support the use of recombinant vaccine against hepatitis B in patients on regular dialysis with HCV infection. © 2011 Blackwell Publishing Ltd.
Full Text Available Many observational studies have found that exposure to dental X-rays is associated with the risk of development of meningioma. However, these findings are inconsistent. We conducted a meta-analysis to assess the relationship between exposure to dental X-rays and the risk of development of meningioma.The PubMed and EMBASE databases were searched to identify eligible studies. Summary odds ratio (OR estimates and 95% confidence intervals (95% CIs were used to compute the risk of meningioma development according to heterogeneity. Subgroup and sensitivity analyses were performed to further explore the potential heterogeneity. Finally, publication bias was assessed.Seven case-control studies involving 6,174 patients and 19,459 controls were included in the meta-analysis. Neither exposure to dental X-rays nor performance of full-mouth panorex X-rays was associated with an increased risk of development of meningioma (overall: OR, 0.97; 95% CI, 0.70-1.32; dental X-rays: OR, 1.05; 95% CI, 0.89-1.25; panorex X-rays: OR, 1.01; 95% CI, 0.76-1.34. However, exposure to bitewing X-rays was associated with a slightly increased risk of development of meningioma (OR, 1.73; 95% CI, 1.28-2.34. Similar results were obtained in the subgroup and sensitivity analyses. Little evidence of publication bias was observed.Based on the currently limited data, there is no association between exposure to dental X-rays and the risk of development of meningioma. However, these results should be cautiously interpreted because of the heterogeneity among studies. Additional large, high-quality clinical trials are needed to evaluate the association between exposure to dental X-rays and the risk of development of meningioma.
Qin, Li-Qiang; Xu, Jia-Ying; Wang, Pei-Yu; Hoshi, Kazuhiko
Many studies have suggested that the intake of soy products may protect against the occurrence of breast cancer because of the considerable amount of isoflavones they contain. To review the results of the observational studies, we performed this meta-analysis of the relevant literature. We searched Medline for reports that examined the association between soyfood consumption (or isoflavone intake) and breast cancer risk from January 1966 to April 2006. The random-effects model was used to estimate the pooled relative risk (RR). Twenty-one independent studies (14 case-control studies and 7 cohort studies) were included in the final analysis. The pooled RR of breast cancer for soyfood intake was 0.75 with a 95% CI of 0.59-0.95. As the main types of soyfood in Japan and China, tofu and miso showed clear protective effects. Isoflavone intake resulted in a 20% decrease in risk (RR = 0.81, 95% CI 0.67-0.99). The pooled RR varied little according to study stratification. When the studies published in Japanese and Chinese were added, the inverse associations between soyfood, tofu and breast cancer risk became slightly stronger. The weak association of miso was possibly due to the high concentration of salt in miso soup. In the present analysis, we did not find strong evidence for publication bias in the combination of the studies. This meta-analysis supported the hypotheses that soyfood intake may be associated with a decreased risk of breast cancer due to the isoflavones. Further epidemiological studies need to be conducted with more comprehensive information about the soyfood, and more accurate assessment of the isoflavones.
Nikoloulopoulos, Aristidis K
A bivariate copula mixed model has been recently proposed to synthesize diagnostic test accuracy studies and it has been shown that it is superior to the standard generalized linear mixed model in this context. Here, we call trivariate vine copulas to extend the bivariate meta-analysis of diagnostic test accuracy studies by accounting for disease prevalence. Our vine copula mixed model includes the trivariate generalized linear mixed model as a special case and can also operate on the original scale of sensitivity, specificity, and disease prevalence. Our general methodology is illustrated by re-analyzing the data of two published meta-analyses. Our study suggests that there can be an improvement on trivariate generalized linear mixed model in fit to data and makes the argument for moving to vine copula random effects models especially because of their richness, including reflection asymmetric tail dependence, and computational feasibility despite their three dimensionality.
Vanhoucke, Elodie; Cousin, Emilie; Baciu, Monica
Growing evidence suggests that age impacts on interhemispheric representation of language. Dichotic listening test allows assessing language lateralization for spoken language and it generally reveals right-ear/left-hemisphere (LH) predominance for language in young adult subjects. According to reported results, elderly would display increasing LH predominance in some studies or stable LH language lateralization for language in others ones. The aim of this study was to depict the main pattern of results in respect with the effect of normal aging on the hemisphere specialization for language by using dichotic listening test. A meta-analysis based on 11 studies has been performed. The inter-hemisphere asymmetry does not seem to increase according to age. A supplementary qualitative analysis suggests that right-ear advantage seems to increase between 40 and 49 y old and becomes stable or decreases after 55 y old, suggesting right-ear/LH decline.
Hori, Megumi; Tanaka, Hirokazu; Wakai, Kenji; Sasazuki, Shizuka; Katanoda, Kota
Systematic evaluation of the association between secondhand smoke exposure and lung cancer in Japan has yet to be conducted. Here, we performed a systematic review and meta-analysis of the relationship between secondhand smoke and lung cancer in Japanese non-smokers. Relevant studies were collected from the MEDLINE and Ichushi Web databases using a combination of search terms and Medical Subject Headings. Eligible studies were identified, and relative risks or odds ratios were extracted to calculate pooled risk estimates. This procedure was performed independently by at least two authors. Stratified analyses were carried out according to study design, publication year, and whether or not potential confounding variables were accounted for. The presence of publication bias was assessed via funnel plots. We identified four cohort studies and five case-control studies. Quantitative synthesis was conducted only for secondhand smoke exposure in the home during adulthood. Of the 12 populations included in meta-analysis, positive secondhand smoke exposure-lung cancer associations were observed in 11, whereas an inverse association was found in the remaining 1. The pooled relative risk of lung cancer associated with secondhand smoke exposure was 1.28 (95% confidence interval: 1.10-1.48). We found no evidence of publication bias, and a significant association remained even when potentially missing studies were included (pooled relative risk: 1.26; 95% confidence interval: 1.09-1.46). The results were stable across different subgroup analyses, including by study design, publication year, and when adjusting for confounding variables. Secondhand smoke exposure in the home during adulthood results in a statistically significant increase in the risk of lung cancer. © The Author 2016. Published by Oxford University Press.
Chen, Yu-Heng; Zou, Xiao-Nong; Zheng, Tong-Zhang; Zhou, Qi; Qiu, Hui; Chen, Yuan-Li; He, Mei; Du, Jia; Lei, Hai-Ke; Zhao, Ping
Studies on the association between spicy food intake and cancer risk have reported inconsistent results. We quantitatively assessed this association by conducting a meta-analysis based on evidence from case-control studies. PubMed, EMBASE, and the Cochrane Library were searched for eligible publications. Combined odds ratios (OR s) with their 95% confidence interval (CI) were calculated using a random- or fixed-effects model. The methodological quality of the included articles was assessed using the Newcastle-Ottawa scale (NOS). All data were analyzed using STATA 11.0 software (version 11.0; StataCorp., College Station, TX, USA). Subgroup analyses were also performed with stratification by region, sex, number of cases, cancer subtype, source of the control group, and NOS score. A total 39 studies from 28 articles fulfilled the inclusion criteria for the meta-analysis (7884 patients with cancer and 10,142 controls). Comparison of the highest versus lowest exposure category in each study revealed a significant OR of 1.76 (95% CI = 1.35-2.29) in spite of significant heterogeneity (P cases, different sources of the control group, and high-quality articles (NOS score of ≥ 7). However, no statistically significant association was observed for women, esophageal cancer, gallbladder cancer, or low-quality articles (NOS score of case-control studies suggested that a higher level of spicy food intake may be associated with an increased incidence of cancer despite significant heterogeneity. More studies are warranted to clarify our understanding of the association between high spicy food intake and the risk of cancer.
Xu, Xiaodong; Yu, Enda; Gao, Xianhua; Song, Ning; Liu, Lianjie; Wei, Xubiao; Zhang, Wei; Fu, Chuangang
Inconsistent results regarding the association between red and processed meat intake and the risk of colorectal adenoma (CRA), the precursor of colorectal cancer (CRC), have been reported. To provide a quantitative assessment of this association, we summarized the evidence from observational studies. Relevant studies were identified in MEDLINE and EMBASE until December 31, 2011. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were pooled with a random-effects model. Between-study heterogeneity was assessed using the Cochran's Q and I(2) statistics. A total of 21 studies (16 case-control studies and five cohort/nested case-control studies) were included in this meta-analysis. The SRRs of CRA were 1.36 (95% CI = 1.17-1.58) for every 100 g/day increase in red meat intake, and 1.24 (95% CI = 1.12-1.36) for the highest versus the lowest level of red meat intake. Nonlinear dose-response meta-analysis indicated that CRA risk increased approximately linearly with increasing intake of red meat up to ~ 90 g/day, where the curve reached its plateau. Subgrouped analyses revealed that the increased risk of CRA with intake of red meat was independent of geographic locations, design and confounders. The SRRs of CRA was 1.28 (95% CI = 1.03-1.60) for per 50 g/day increase in processed meat intake, and 1.17 (95% CI = 1.08-1.26) for the highest versus the lowest level of processed meat intake. Increased intake of red and processed meat is associated with significantly increased risk of CRA. Copyright © 2012 UICC.
Dinu, Monica; Abbate, Rosanna; Gensini, Gian Franco; Casini, Alessandro; Sofi, Francesco
Beneficial effects of vegetarian and vegan diets on health outcomes have been supposed in previous studies. Aim of this study was to clarify the association between vegetarian, vegan diets, risk factors for chronic diseases, risk of all-cause mortality, incidence, and mortality from cardio-cerebrovascular diseases, total cancer and specific type of cancer (colorectal, breast, prostate and lung), through meta-analysis. A comprehensive search of Medline, EMBASE, Scopus, The Cochrane Library, and Google Scholar was conducted. Eighty-six cross-sectional and 10 cohort prospective studies were included. The overall analysis among cross-sectional studies reported significant reduced levels of body mass index, total cholesterol, LDL-cholesterol, and glucose levels in vegetarians and vegans versus omnivores. With regard to prospective cohort studies, the analysis showed a significant reduced risk of incidence and/or mortality from ischemic heart disease (RR 0.75; 95% CI, 0.68 to 0.82) and incidence of total cancer (RR 0.92; 95% CI 0.87 to 0.98) but not of total cardiovascular and cerebrovascular diseases, all-cause mortality and mortality from cancer. No significant association was evidenced when specific types of cancer were analyzed. The analysis conducted among vegans reported significant association with the risk of incidence from total cancer (RR 0.85; 95% CI, 0.75 to 0.95), despite obtained only in a limited number of studies. This comprehensive meta-analysis reports a significant protective effect of a vegetarian diet versus the incidence and/or mortality from ischemic heart disease (-25%) and incidence from total cancer (-8%). Vegan diet conferred a significant reduced risk (-15%) of incidence from total cancer.
Geng, Qirong; Wang, Jing; Lan, Yadong; Zhan, Youqing; Xu, Dazhi
Aim The association between vitamin intake and gastric cancer (GC) has been widely debated due to the relatively weak evidence. In this study, a meta-analysis of prospective and well designed observational studies were performed to explore this association. Methods MEDLINE, Cochrane Library, and Sciencedirect were searched for studies of vitamin consumption and gastric cancer. This produced 47 relevant studies covering 1,221,392 human subjects. Random effects models were used to estimate summary relative risk (RR). Dose-response, subgroup, sensitivity, meta-regression, and publication bias analyses were conducted. Results The RR of gastric cancer in the group with the highest vitamin intake was compared to that of the lowest intake group. Total vitamin intake was 0.78 (95% CI, 0.71−0.83). In 9 studies that individuals were given doses at least 4 times above the tolerable upper intake (UL) vitamins, the RR was 1.20 (95% CI, 0.99−1.44). However, in 17 studies that individuals received doses below the UL, the RR was 0.76 (95% CI, 0.68−0.86). Dose-response analysis was conducted on different increments in different types of vitamins (vitamin A: 1.5 mg/day, vitamin C: 100 mg/day, vitamin E: 10 mg/day) intake with a significant reduction in the risk of gastric cancer, respectively, 29% in vitamin A, 26% in vitamin C, and 24% in vitamin E. Conclusion This meta-analysis clearly demonstrated that low doses of vitamins can significantly reduce the risk of GC, especially vitamin A, vitamin C, vitamin E. PMID:25549091
Pelucchi, Claudio; Galeone, Carlotta; Bach, Jean-François; La Vecchia, Carlo; Chatenoud, Liliane
Findings on pet exposure and the risk of atopic dermatitis (AD) in children are inconsistent. With the aim to summarize the results of exposure to different pets on AD, we undertook a meta-analysis of epidemiologic studies on this issue. In August 2012, we conducted a systematic literature search in Medline and Embase. We included analytic studies considering exposure to dogs, cats, other pets, or pets overall during pregnancy, infancy, and/or childhood, with AD assessment performed during infancy or childhood. We calculated summary relative risks and 95% CIs using both fixed- and random-effects models. We computed summary estimates across selected subgroups. Twenty-six publications from 21 birth cohort studies were used in the meta-analyses. The pooled relative risks of AD for exposure versus no exposure were 0.72 (95% CI, 0.61-0.85; I(2) = 46%; results based on 15 studies) for exposure to dogs, 0.94 (95% CI, 0.76-1.16; I(2) = 54%; results based on 13 studies) for exposure to cats, and 0.75 (95% CI, 0.67-0.85; I(2) = 54%; results based on 11 studies) for exposure to pets overall. No heterogeneity emerged across the subgroups examined, except for geographic area. This meta-analysis reported a favorable effect of exposure to dogs and pets on the risk of AD in infants or children, whereas no association emerged with exposure to cats. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.
Full Text Available Phylogenetic comparative methods (PCMs have been applied widely in analyzing data from related species but their fit to data is rarely assessed.Can one determine whether any particular comparative method is typically more appropriate than others by examining comparative data sets?I conducted a meta-analysis of 122 phylogenetic data sets found by searching all papers in JEB, Blackwell Synergy and JSTOR published in 2002-2005 for the purpose of assessing the fit of PCMs. The number of species in these data sets ranged from 9 to 117.I used the Akaike information criterion to compare PCMs, and then fit PCMs to bivariate data sets through REML analysis. Correlation estimates between two traits and bootstrapped confidence intervals of correlations from each model were also compared.For phylogenies of less than one hundred taxa, the Independent Contrast method and the independent, non-phylogenetic models provide the best fit.For bivariate analysis, correlations from different PCMs are qualitatively similar so that actual correlations from real data seem to be robust to the PCM chosen for the analysis. Therefore, researchers might apply the PCM they believe best describes the evolutionary mechanisms underlying their data.
Zillikens, M Carola; Demissie, Serkalem; Hsu, Yi-Hsiang
Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorpt...... a meta-analysis of genome-wide association studies for whole body lean body mass and find five novel genetic loci to be significantly associated.......-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p
Cho, Yoon Shin; Chen, Chien-Hsiun; Hu, Cheng
We conducted a three-stage genetic study to identify susceptibility loci for type 2 diabetes (T2D) in east Asian populations. We followed our stage 1 meta-analysis of eight T2D genome-wide association studies (6,952 cases with T2D and 11,865 controls) with a stage 2 in silico replication analysis...... (5,843 cases and 4,574 controls) and a stage 3 de novo replication analysis (12,284 cases and 13,172 controls). The combined analysis identified eight new T2D loci reaching genome-wide significance, which mapped in or near GLIS3, PEPD, FITM2-R3HDML-HNF4A, KCNK16, MAEA, GCC1-PAX4, PSMD6 and ZFAND3...
Kaplan, Yusuf Cem; Keskin-Arslan, Elif; Acar, Selin; Sozmen, Kaan
We undertook an exclusive meta-analysis of cohort studies investigating the possible link between prenatal selective serotonin reuptake inhibitor (SSRI) exposure and autism spectrum disorders (ASD) in children to further investigate our previous suggestion of confounding by indication. The point estimates regarding the following cohorts were extracted and pooled: (1) pregnant women who discontinued SSRI until 3 months before pregnancy; (2) pregnant women who were exposed to SSRI during pregnancy; and (3) pregnant women with maternal psychiatric disorder but no exposure to SSRI during pregnancy. Although the pooled point estimate of the first cohort showed a trend for increase, it did not reach significance. The pooled point estimates of the latter cohorts showed a significant association with ASD which strengthens our previous suggestion of confounding by indication. Future studies should be adequately designed to differentiate whether the previously suggested association is a result of maternal psychiatric disorder or SSRI exposure or both. © 2017 The British Pharmacological Society.
Jess, Tine; Gamborg, Michael; Matzen, Peter
the inclusion criteria and reported SIRs of colorectal cancer (CRC) in CD varying from 0.9 to 2.2. The pooled SIR for CRC was significantly increased (SIR, 1.9; 95% CI 1.4-2.5), as was the risk for colon cancer separately (SIR, 2.5; 95% CI 1.7-3.5). Regarding small bowel cancer, five studies reported SIRs...... ranging from 3.4 to 66.7, and the overall pooled estimate was 27.1 (95% CI 14.9-49.2). CONCLUSIONS: The present meta-analysis of intestinal cancer risk in CD, based on population-based studies only, revealed an overall increased risk of both CRC and small bowel cancer among patients with CD. However, some...
Joshi, Amit D; Andersson, Charlotte; Buch, Stephan
discovery studies (8720 cases and 55,152 controls). We performed an inverse variance weighted, fixed-effects meta-analysis of study-specific estimates to identify single-nucleotide polymorphisms that were associated independently with gallstone disease. Associations were replicated in 6489 cases and 62...... in TM4SF4 (OR, 1.12; 95% CI, 1.08-1.16; P = 6.09 × 10(-11)), rs2547231 in SULT2A1 (encodes a sulfoconjugation enzyme that acts on hydroxysteroids and cholesterol-derived sterol bile acids) (OR, 1.17; 95% CI, 1.12-1.21; P = 2.24 × 10(-10)), rs1260326 in glucokinase regulatory protein (OR, 1.12; 95% CI, 1...
Das, Stephanie L M; Papachristou, George I; De Campos, Tercio; Panek, Jozefa; Poves Prim, Ignasi; Serrablo, Alejandro; Parks, Rowan W; Uomo, Generoso; Windsor, John A; Petrov, Maxim S
Organ failure is a major determinant of mortality in patients with acute pancreatitis. These patients usually require admission to high dependency or intensive care units and consume considerable health care resources. Given a low incidence rate of organ failure and a lack of large non-interventional studies in the field of acute pancreatitis, the characteristics of organ failure that influence outcomes of patients with acute pancreatitis remain largely unknown. Therefore, the Pancreatitis Across Nations Clinical Research and Education Alliance (PANCREA) aims to conduct a meta-analysis of individual patient data from prospective non-interventional studies to determine the influence of timing, duration, sequence, and combination of different organ failures on mortality in patients with acute pancreatitis. Pancreatologists currently active with acute pancreatitis clinical research will be invited to contribute. To be eligible for inclusion patients will have to meet the criteria of acute pancreatitis, develop at least one organ failure during the first week of hospitalization, and not be enrolled into an intervention study. Raw data will then be collated and checked. Individual patient data analysis based on a logistic regression model with adjustment for confounding variables will be done. For all analyses, corresponding 95% confidence intervals and P values will be reported. This collaborative individual patient data meta-analysis will answer important clinical questions regarding patients with acute pancreatitis that develop organ failure. Information derived from this study will be used to optimize routine clinical management and improve care strategies. It can also help validate outcome definitions, allow comparability of results and form a more accurate basis for patient allocation in further clinical studies.
Aune, Dagfinn; Schlesinger, Sabrina; Norat, Teresa; Riboli, Elio
Smoking is an established risk factor for cardiovascular disease including coronary heart disease and stroke, however, data regarding smoking and sudden cardiac death have not been summarized in a meta-analysis previously. We therefore conducted a systematic review and meta-analysis to clarify this association. We searched the PubMed and Embase databases for studies of smoking and sudden cardiac death up to July 20th 2017. Prospective studies were included if they reported adjusted relative risk (RR) estimates and 95% confidence intervals (CIs) for smoking and sudden cardiac death. Summary RRs were estimated by use of a random effects model. Twelve prospective studies were included. The summary RR was 3.06 (95% CI 2.46-3.82, I 2 = 41%, p heterogeneity = 0.12, n = 7) for current smokers and 1.38 (95% CI 1.20-1.60, I 2 = 0%, p heterogeneity = 0.55, n = 7) for former smokers compared to never smokers. For four studies using non-current (never + former) smokers as the reference category the summary RR among current smokers was 2.08 (95% CI 1.70-2.53, I 2 = 18%, p heterogeneity = 0.30). The results persisted in most of the subgroup analyses. There was no evidence of publication bias. These results confirm that smoking increases the risk of sudden cardiac death. Any further studies should investigate in more detail the effects of duration of smoking, number of cigarettes per day, pack-years, and time since quitting smoking and sudden cardiac death.
Zabalza, Michel; Subirana, Isaac; Lluis-Ganella, Carla; Sayols-Baixeras, Sergi; de Groot, Eric; Arnold, Roman; Cenarro, Ana; Ramos, Rafel; Marrugat, Jaume; Elosua, Roberto
Recent studies have identified several genetic variants associated with coronary artery disease. Some of these genetic variants are not associated with classical cardiovascular risk factors and the mechanism of such associations is unclear. The aim of the study was to determine whether these genetic variants are related to subclinical atherosclerosis measured by carotid intima media thickness, carotid stiffness, and ankle brachial index. A cross-sectional study nested in the follow-up of the REGICOR cohort was undertaken. The study included 2667 individuals. Subclinical atherosclerosis measurements were performed with standardized methods. Nine genetic variants were genotyped to assess associations with subclinical atherosclerosis, individually and in a weighted genetic risk score. A systematic review and meta-analysis of previous studies that analyzed these associations was undertaken. Neither the selected genetic variants nor the genetic risk score were significantly associated with subclinical atherosclerosis. In the meta-analysis, the rs1746048 (CXCL12; n = 10581) risk allele was directly associated with carotid intima-media thickness (β = 0.008; 95% confidence interval, 0.001-0.015), whereas the rs6725887 (WDR12; n = 7801) risk allele was inversely associated with this thickness (β = -0.013; 95% confidence interval, -0.024 to -0.003). The analyzed genetic variants seem to mediate their association with coronary artery disease through different mechanisms. Our results generate the hypothesis that the CXCL12 variant appears to influence coronary artery disease risk through arterial remodeling and thickening, whereas the WDR12 risk variant could be related to higher plaque vulnerability. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.
Virtanen, Marianna; Jokela, Markus; Madsen, Ida Eh; Magnusson Hanson, Linda L; Lallukka, Tea; Nyberg, Solja T; Alfredsson, Lars; Batty, G David; Bjorner, Jakob B; Borritz, Marianne; Burr, Hermann; Dragano, Nico; Erbel, Raimund; Ferrie, Jane E; Heikkilä, Katriina; Knutsson, Anders; Koskenvuo, Markku; Lahelma, Eero; Nielsen, Martin L; Oksanen, Tuula; Pejtersen, Jan H; Pentti, Jaana; Rahkonen, Ossi; Rugulies, Reiner; Salo, Paula; Schupp, Jürgen; Shipley, Martin J; Siegrist, Johannes; Singh-Manoux, Archana; Suominen, Sakari B; Theorell, Töres; Vahtera, Jussi; Wagner, Gert G; Wang, Jian Li; Yiengprugsawan, Vasoontara; Westerlund, Hugo; Kivimäki, Mika
Objectives This systematic review and meta-analysis combined published study-level data and unpublished individual-participant data with the aim of quantifying the relation between long working hours and the onset of depressive symptoms. Methods We searched PubMed and Embase for published prospective cohort studies and included available cohorts with unpublished individual-participant data. We used a random-effects meta-analysis to calculate summary estimates across studies. Results We identified ten published cohort studies and included unpublished individual-participant data from 18 studies. In the majority of cohorts, long working hours was defined as working ≥55 hours per week. In multivariable-adjusted meta-analyses of 189 729 participants from 35 countries [96 275 men, 93 454 women, follow-up ranging from 1-5 years, 21 747 new-onset cases), there was an overall association of 1.14 (95% confidence interval (CI) 1.03-1.25] between long working hours and the onset of depressive symptoms, with significant evidence of heterogeneity (I 2 =45.1%, P=0.004). A moderate association between working hours and depressive symptoms was found in Asian countries (1.50, 95% CI 1.13-2.01), a weaker association in Europe (1.11, 95% CI 1.00-1.22), and no association in North America (0.97, 95% CI 0.70-1.34) or Australia (0.95, 95% CI 0.70-1.29). Differences by other characteristics were small. Conclusions This observational evidence suggests a moderate association between long working hours and onset of depressive symptoms in Asia and a small association in Europe.
Bae, Jong-Myon; Kim, Eun Hee
The established theory that breast density is an independent predictor of breast cancer risk is based on studies targeting white women in the West. More Asian women than Western women have dense breasts, but the incidence of breast cancer is lower among Asian women. This meta-analysis investigated the association between breast density in mammography and breast cancer risk in Asian women. PubMed and Scopus were searched, and the final date of publication was set as December 31, 2015. The effect size in each article was calculated using the interval-collapse method. Summary effect sizes (sESs) and 95% confidence intervals (CIs) were calculated by conducting a meta-analysis applying a random effect model. To investigate the dose-response relationship, random effect dose-response meta-regression (RE-DRMR) was conducted. Six analytical epidemiology studies in total were selected, including one cohort study and five case-control studies. A total of 17 datasets were constructed by type of breast density index and menopausal status. In analyzing the subgroups of premenopausal vs. postmenopausal women, the percent density (PD) index was confirmed to be associated with a significantly elevated risk for breast cancer (sES, 2.21; 95% CI, 1.52 to 3.21; I 2 =50.0%). The RE-DRMR results showed that the risk of breast cancer increased 1.73 times for each 25% increase in PD in postmenopausal women (95% CI, 1.20 to 2.47). In Asian women, breast cancer risk increased with breast density measured using the PD index, regardless of menopausal status. We propose the further development of a breast cancer risk prediction model based on the application of PD in Asian women.
Yuan, Sheng; Li, Xia; Jin, Yalei; Lu, Jinping
Although epidemiological studies have examined the role of chocolate in preventing cardiometabolic disease, the results remain inconsistent. Herein, we conducted a meta-analysis of prospective studies to determine the association between chocolate intake and risk of coronary heart disease (CHD), stroke, and diabetes. A systematical search in PubMed and Embase through March 2017, together with reference scrutiny of relevant literatures, was performed to identify eligible studies. Relative risks (RRs) and 95% confidence intervals (CIs) were pooled using random effect models. Fourteen prospective studies of primary prevention with 508,705 participants were finally included, with follow-up durations ranging from 5 to 16 years. The summary RRs for the highest versus lowest chocolate consumption were 0.90 (95% CI: 0.82-0.97; n = 6) for CHD, 0.84 (95% CI: 0.78-0.90; n = 7) for stroke, and 0.82 (95% CI: 0.70-0.96; n = 5) for diabetes. Dose-response meta-analysis suggested a nonlinear association of chocolate consumption with all outcomes. For both CHD and stroke, there was little additional risk reduction when consuming chocolate ≥3 servings/week (one serving was defined as 30 g of chocolate). For diabetes, the peak protective effect of chocolate emerged at 2 servings/week (RR: 0.75, 95% CI: 0.63-0.89), with no benefit observed when increasing consumption above 6 servings/week. In conclusion, chocolate intake is associated with decreased risks of CHD, stroke, and diabetes. Consuming chocolate in moderation (≤6 servings/week) may be optimal for preventing these disorders.
Full Text Available Although epidemiological studies have examined the role of chocolate in preventing cardiometabolic disease, the results remain inconsistent. Herein, we conducted a meta-analysis of prospective studies to determine the association between chocolate intake and risk of coronary heart disease (CHD, stroke, and diabetes. A systematical search in PubMed and Embase through March 2017, together with reference scrutiny of relevant literatures, was performed to identify eligible studies. Relative risks (RRs and 95% confidence intervals (CIs were pooled using random effect models. Fourteen prospective studies of primary prevention with 508,705 participants were finally included, with follow-up durations ranging from 5 to 16 years. The summary RRs for the highest versus lowest chocolate consumption were 0.90 (95% CI: 0.82–0.97; n = 6 for CHD, 0.84 (95% CI: 0.78–0.90; n = 7 for stroke, and 0.82 (95% CI: 0.70–0.96; n = 5 for diabetes. Dose–response meta-analysis suggested a nonlinear association of chocolate consumption with all outcomes. For both CHD and stroke, there was little additional risk reduction when consuming chocolate ≥3 servings/week (one serving was defined as 30 g of chocolate. For diabetes, the peak protective effect of chocolate emerged at 2 servings/week (RR: 0.75, 95% CI: 0.63–0.89, with no benefit observed when increasing consumption above 6 servings/week. In conclusion, chocolate intake is associated with decreased risks of CHD, stroke, and diabetes. Consuming chocolate in moderation (≤6 servings/week may be optimal for preventing these disorders.
Arcelus, Jon; Mitchell, Alex J; Wales, Jackie; Nielsen, Søren
Morbidity and mortality rates in patients with eating disorders are thought to be high, but exact rates remain to be clarified. To systematically compile and analyze the mortality rates in individuals with anorexia nervosa (AN), bulimia nervosa (BN), and eating disorder not otherwise specified (EDNOS). A systematic literature search, appraisal, and meta-analysis were conducted of the MEDLINE/PubMed, PsycINFO, and Embase databases and 4 full-text collections (ie, ScienceDirect, Ingenta Select, Ovid, and Wiley-Blackwell Interscience). English-language, peer-reviewed articles published between January 1, 1966, and September 30, 2010, that reported mortality rates in patients with eating disorders. Primary data were extracted as raw numbers or confidence intervals and corrected for years of observation and sample size (ie, person-years of observation). Weighted proportion meta-analysis was used to adjust for study size using the DerSimonian-Laird model to allow for heterogeneity inclusion in the analysis. From 143 potentially relevant articles, we found 36 quantitative studies with sufficient data for extraction. The studies reported outcomes of AN during 166 642 person-years, BN during 32 798 person-years, and EDNOS during 22 644 person-years. The weighted mortality rates (ie, deaths per 1000 person-years) were 5.1 for AN, 1.7 for BN, and 3.3 for EDNOS. The standardized mortality ratios were 5.86 for AN, 1.93 for BN, and 1.92 for EDNOS. One in 5 individuals with AN who died had committed suicide. Individuals with eating disorders have significantly elevated mortality rates, with the highest rates occurring in those with AN. The mortality rates for BN and EDNOS are similar. The study found age at assessment to be a significant predictor of mortality for patients with AN. Further research is needed to identify predictors of mortality in patients with BN and EDNOS.
Full Text Available OBJECTIVES: To provide a quantitative assessment of the association between excess body weight, interpreted as increased body mass index (BMI, and the risk of gallbladder cancer (GBC. METHODS: We identified eligible studies in Medline and EMBASE up to 1 February 2015, and reference lists of retrieved articles. Summary relative risks with their 95% confidence intervals were calculated in a random-effects model. Subgroup analyses were performed according to study design, gender, geographic location, ascertainment of exposure and adjustment for confounders. RESUITS: A total of 12 cohort studies and 8 case-control studies were included in the meta-analysis. Overall, compared with “normal” weight, the summary relative risks of GBC were 1.14 (95% CI, 1.04–1.25 for overweight individuals (BMI 25–30 kg/m2 and 1.56 (95% CI, 1.41–1.73 for obese individuals (BMI > 30 kg/m2. Obese women had a higher risk of GBC than men did (women: SRRs 1.67, 95% CI 1.38–2.02; men: SRRs 1.42, 95% CI 1.21–1.66, and there was significant association between overweight and GBC risk in women (SRRs 1.26, 95% CI 1.13–1.40, but not in men (SRRs 1.06, 95% CI 0.94–1.20. CONCLUSIONS: Findings from this meta-analysis indicate that obesity is associated with an increased risk of GBC, especially in women. Overweight is associated with GBC risk only in women.
Yuan, Sheng; Li, Xia; Jin, Yalei; Lu, Jinping
Although epidemiological studies have examined the role of chocolate in preventing cardiometabolic disease, the results remain inconsistent. Herein, we conducted a meta-analysis of prospective studies to determine the association between chocolate intake and risk of coronary heart disease (CHD), stroke, and diabetes. A systematical search in PubMed and Embase through March 2017, together with reference scrutiny of relevant literatures, was performed to identify eligible studies. Relative risks (RRs) and 95% confidence intervals (CIs) were pooled using random effect models. Fourteen prospective studies of primary prevention with 508,705 participants were finally included, with follow-up durations ranging from 5 to 16 years. The summary RRs for the highest versus lowest chocolate consumption were 0.90 (95% CI: 0.82–0.97; n = 6) for CHD, 0.84 (95% CI: 0.78–0.90; n = 7) for stroke, and 0.82 (95% CI: 0.70–0.96; n = 5) for diabetes. Dose–response meta-analysis suggested a nonlinear association of chocolate consumption with all outcomes. For both CHD and stroke, there was little additional risk reduction when consuming chocolate ≥3 servings/week (one serving was defined as 30 g of chocolate). For diabetes, the peak protective effect of chocolate emerged at 2 servings/week (RR: 0.75, 95% CI: 0.63–0.89), with no benefit observed when increasing consumption above 6 servings/week. In conclusion, chocolate intake is associated with decreased risks of CHD, stroke, and diabetes. Consuming chocolate in moderation (≤6 servings/week) may be optimal for preventing these disorders. PMID:28671591
Tomasino, Barbara; Fregona, Sara; Skrap, Miran; Fabbro, Franco
The brain network governing meditation has been studied using a variety of meditation practices and techniques practices eliciting different cognitive processes (e.g., silence, attention to own body, sense of joy, mantras, etc.). It is very possible that different practices of meditation are subserved by largely, if not entirely, disparate brain networks. This assumption was tested by conducting an activation likelihood estimation (ALE) meta-analysis of meditation neuroimaging studies, which assessed 150 activation foci from 24 experiments. Different ALE meta-analyses were carried out. One involved the subsets of studies involving meditation induced through exercising focused attention (FA). The network included clusters bilaterally in the medial gyrus, the left superior parietal lobe, the left insula and the right supramarginal gyrus (SMG). A second analysis addressed the studies involving meditation states induced by chanting or by repetition of words or phrases, known as “mantra.” This type of practice elicited a cluster of activity in the right SMG, the SMA bilaterally and the left postcentral gyrus. Furthermore, the last analyses addressed the effect of meditation experience (i.e., short- vs. long-term meditators). We found that frontal activation was present for short-term, as compared with long-term experience meditators, confirming that experts are better enabled to sustain attentional focus, rather recruiting the right SMG and concentrating on aspects involving disembodiment. PMID:23316154
Full Text Available The brain network governing meditation has been studied using a variety of meditation practices and techniques practices eliciting different cognitive processes (e.g., silence, attention to own body, sense of joy, mantras, etc.. It is very possible that different practices of meditation are subserved by largely, if not entirely, disparate brain networks. This assumption was tested by conducting an activation likelihood estimation (ALE meta-analysis of meditation neuroimaging studies, which assessed 150 activation foci from 24 experiments. Different ALE meta-analyses were carried out. One involved the subsets of studies involving meditation induced through exercising focused attention. The network included clusters bilaterally in the medial gyrus, the left superior parietal lobe, the left insula and the right supramarginal gyrus. A second analysis addressed the studies involving meditation states induced by chanting or by repetition of words or phrases, known as ‘mantra’. This type of practice elicited a cluster of activity in the right supramarginal gyrus, the SMA bilaterally and the left postcentral gyrus. Furthermore, the last analyses addressed the effect of meditation experience (i.e., short- vs. long-term meditators. We found that frontal activation was present for short-term, as compared with long-term experience meditators, confirming that experts are better enabled to sustain attentional focus, rather recruiting the right supramarginal gyrus and concentrating on aspects involving disembodiment.
Tan, XiangZhou; Wen, QiaoCheng; Wang, Ran; Chen, ZhiKang
Recently, there has been a controversial discussion about the prognostic value of chemotherapy-induced neutropenia (CIN) in colorectal cancer patients. Thus, a meta-analysis was conducted to determine the relationship between CIN and the prognosis of colorectal cancer patients. We searched the PubMed, EMBASE, and Cochrane library databases to identify studies evaluating the association between CIN and colorectal cancer prognosis. Pooled random/fixed effect models were used to calculate pooled hazard ratios (HRs) and 95% confidence intervals (CIs) to assess the association. Eight studies were selected for the meta-analysis, for a total of 2,745 patients. There was significant improved survival among colorectal cancer patients with CIN (HR = 0.62, 95% CI = 0.47-0.76). However, significant heterogeneity was found (p = 0.000, Ι 2 = 75.0%). Through subgroup analysis, we could greatly eliminate the heterogeneity and found that neutropenia was associated with better survival in stage IV colorectal cancer patients, no matter the HR calculated by overall survival (OS) or progression-free survival (PFS). Meanwhile, the prognostic value of neutropenia in stage II/III colorectal cancer can be found when the HR is calculated by disease-free survival (DFS). Additionally, we observed significant differences after stratification according to various tumor stages, endpoints, and the use of G-CSF. Our results which, based on a cohort study, indicate that CIN is associated with improved survival in patients with colorectal cancer. However, further randomized controlled trials are warranted.
Abbott, T E F; Ahmad, T; Phull, M K; Fowler, A J; Hewson, R; Biccard, B M; Chew, M S; Gillies, M; Pearse, R M
The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32-0.77); P<0.01], but no difference in complication rates [OR 1.02 (0.88-1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62-0.92); P<0.01; I 2 =87%] and reduced complication rates [OR 0.73 (0.61-0.88); P<0.01; I 2 =89%). Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine. Copyright © 2017 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.
Carl J. Dunst
Full Text Available Incorporating the interests and preferences of young children with autism spectrum disorders into interventions to promote prosocial behavior and decrease behavior excesses has emerged as a promising practice for addressing the core features of autism. The efficacy of interest-based early intervention practices was examined in a meta-analysis of 24 studies including 78 children 2 to 6 years of age diagnosed with autism spectrum disorders. Effect size analyses of intervention versus nonintervention conditions and high-interest versus low-interest contrasts indicated that interest-based intervention practices were effective in terms of increasing prosocial and decreasing aberrant child behavior. Additionally, interest-based interventions that focused on two of the three core features of autism spectrum disorders (poor communication, poor interpersonal relationships were found most effective in influencing child outcomes. Implications for very early intervention are discussed in terms addressing the behavior markers of autism spectrum disorders before they become firmly established.
Briley, Daniel A; Tucker-Drob, Elliot M
Genes account for increasing proportions of variation in cognitive ability across development, but the mechanisms underlying these increases remain unclear. We conducted a meta-analysis of longitudinal behavioral genetic studies spanning infancy to adolescence. We identified relevant data from 16 articles with 11 unique samples containing a total of 11,500 twin and sibling pairs who were all reared together and measured at least twice between the ages of 6 months and 18 years. Longitudinal behavioral genetic models were used to estimate the extent to which early genetic influences on cognition were amplified over time and the extent to which innovative genetic influences arose with time. Results indicated that in early childhood, innovative genetic influences predominate but that innovation quickly diminishes, and amplified influences account for increasing heritability following age 8 years.
Schmidt, Henk G.; van der Molen, Henk T.; te Winkel, Wilco W. R.; Wijnen, Wynand H. F. W.
Effects of problem-based learning as reported in curricular comparison studies have been shown to be inconsistent over different medical schools. Therefore, we decided to summarize effects of a single well-established problem-based curriculum rather than to add up sometimes-conflicting findings from different problem-based curricula. Effect sizes…
Tielemans, S. M. A. J.; Altorf-van der Kuil, W.; Engberink, M. F.; Brink, E. J.; van Baak, M. A.; Bakker, S. J. L.; Geleijnse, J. M.
There is growing evidence from epidemiological studies that dietary protein may beneficially influence blood pressure (BP), but findings are inconclusive. We performed a meta-analysis of 29 observational studies and randomized controlled trials (RCTs) of dietary protein and types of protein in
Tielemans, S.M.A.J.; Altorf-van der Kuil, W.; Engberink, M.F.; Brink, E.J.; Baak, van M.A.; Bakker, S.J.; Geleijnse, J.M.
There is growing evidence from epidemiological studies that dietary protein may beneficially influence blood pressure (BP), but findings are inconclusive. We performed a meta-analysis of 29 observational studies and randomized controlled trials (RCTs) of dietary protein and types of protein in
Hartemink, Nienke; Boshuizen, Hendriek C; Nagelkerke, Nico J D; Jacobs, Monique A M; Houwelingen, Hans C van
Studies on a dose-response relation often report separate relative risks for several risk classes compared with a referent class. When performing a meta-analysis of such studies, one has to convert these relative risks into an overall relative risk for a continuous effect. Apart from taking the
Conclusion: Despite the limitations such as low number of studies, this meta-analysis suggests chronic toxoplasmosis as a possible risk factor for type 2 DM. However, based on random effects model no statistically significant association was observed between T. gondii and type 1 DM. It is highly recommended for researchers to carry out more accurate studies aiming to better understand this association.
Hummel, Eberhard; Randler, Christoph
Prior research states that the use of living animals in the classroom leads to a higher knowledge but those previous studies have methodological and statistical problems. We applied a meta-analysis and developed a treatment-control study in a middle school classroom. The treatments (film vs. living animal) differed only by the presence of the…
Liu, Xuejiao; Zhang, Dongdong; Liu, Yu; Sun, Xizhuo; Han, Chengyi; Wang, Bingyuan; Ren, Yongcheng; Zhou, Junmei; Zhao, Yang; Shi, Yuanyuan; Hu, Dongsheng; Zhang, Ming
Despite the inverse association between physical activity (PA) and incident hypertension, a comprehensive assessment of the quantitative dose-response association between PA and hypertension has not been reported. We performed a meta-analysis, including dose-response analysis, to quantitatively evaluate this association. We searched PubMed and Embase databases for articles published up to November 1, 2016. Random effects generalized least squares regression models were used to assess the quantitative association between PA and hypertension risk across studies. Restricted cubic splines were used to model the dose-response association. We identified 22 articles (29 studies) investigating the risk of hypertension with leisure-time PA or total PA, including 330 222 individuals and 67 698 incident cases of hypertension. The risk of hypertension was reduced by 6% (relative risk, 0.94; 95% confidence interval, 0.92-0.96) with each 10 metabolic equivalent of task h/wk increment of leisure-time PA. We found no evidence of a nonlinear dose-response association of PA and hypertension ( P nonlinearity =0.094 for leisure-time PA and 0.771 for total PA). With the linear cubic spline model, when compared with inactive individuals, for those who met the guidelines recommended minimum level of moderate PA (10 metabolic equivalent of task h/wk), the risk of hypertension was reduced by 6% (relative risk, 0.94; 95% confidence interval, 0.92-0.97). This meta-analysis suggests that additional benefits for hypertension prevention occur as the amount of PA increases. © 2017 American Heart Association, Inc.
Schwingshackl, Lukas; Hoffmann, Georg; Lampousi, Anna-Maria; Knüppel, Sven; Iqbal, Khalid; Schwedhelm, Carolina; Bechthold, Angela; Schlesinger, Sabrina; Boeing, Heiner
The aim of this systematic review and meta-analysis was to synthesize the knowledge about the relation between intake of 12 major food groups and risk of type 2 diabetes (T2D). We conducted a systematic search in PubMed, Embase, Medline (Ovid), Cochrane Central, and Google Scholar for prospective studies investigating the association between whole grains, refined grains, vegetables, fruits, nuts, legumes, eggs, dairy, fish, red meat, processed meat, and sugar-sweetened beverages (SSB) on risk of T2D. Summary relative risks were estimated using a random effects model by contrasting categories, and for linear and non-linear dose-response relationships. Six out of the 12 food-groups showed a significant relation with risk of T2D, three of them a decrease of risk with increasing consumption (whole grains, fruits, and dairy), and three an increase of risk with increasing consumption (red meat, processed meat, and SSB) in the linear dose-response meta-analysis. There was evidence of a non-linear relationship between fruits, vegetables, processed meat, whole grains, and SSB and T2D risk. Optimal consumption of risk-decreasing foods resulted in a 42% reduction, and consumption of risk-increasing foods was associated with a threefold T2D risk, compared to non-consumption. The meta-evidence was graded "low" for legumes and nuts; "moderate" for refined grains, vegetables, fruit, eggs, dairy, and fish; and "high" for processed meat, red meat, whole grains, and SSB. Among the investigated food groups, selecting specific optimal intakes can lead to a considerable change in risk of T2D.
Woliński, Kosma; Stangierski, Adam; Gurgul, Edyta; Bromińska, Barbara; Czarnywojtek, Agata; Lodyga, Martha; Ruchała, Marek
Acromegaly results from oversecretion of growth hormone and subsequently insulin growth factor-1. According to some authors, the disease can cause increased prevalence of nodular goitre and thyroid cancer (TC). However, the number of studies comparing acromegalic patients with control groups is low. We aimed to assess the prevalence of thyroid lesions in patients with acromegaly in comparison to an age- and sex-matched control group and to update the meta-analysis previously performed in our department by the same authors. We searched medical documentation of patients with acromegaly treated in our department between 2003 and 2013. The prevalence of thyroid abnormalities was compared with the group of patients with hormonally inactive adrenal incidentalomas. To perform the meta-analytic part of the paper we also searched ten databases to find relevant papers. Two hundred and five patients with acromegaly and 184 patients with incidentalomas were included. Any thyroid lesions were present in 77.6% of patients with acromegaly vs. 63.0% with incidentalomas (p = 0.002), multinodular goitre - 66.8% vs. 47.8% (p = 0.0002), and TC- 5.4% vs. 2.7% (p = 0.21) respectively. For thyroid lesions the pooled odds ratio (OR) was 3.1 (95% confidence interval [CI] 1.8-5.5), and for TCs the OR was 4.5 (95% CI 1.9-10.3). According to our results thyroid lesions were significantly more common in patients with acromegaly; in case of TC the difference was not significant. The updated meta-analysis showed significantly increased prevalence of both disorders. In conclusion, systematic thyroid examination should be an important part of follow-up in case of acromegalic patients. (Endokrynol Pol 2017; 68 (1): 2-6).
Marioni, Riccardo E; McRae, Allan F; Bressler, Jan; Colicino, Elena; Hannon, Eilis; Li, Shuo; Prada, Diddier; Smith, Jennifer A; Trevisi, Letizia; Tsai, Pei-Chien; Vojinovic, Dina; Simino, Jeannette; Levy, Daniel; Liu, Chunyu; Mendelson, Michael; Satizabal, Claudia L; Yang, Qiong; Jhun, Min A; Kardia, Sharon L R; Zhao, Wei; Bandinelli, Stefania; Ferrucci, Luigi; Hernandez, Dena G; Singleton, Andrew B; Harris, Sarah E; Starr, John M; Kiel, Douglas P; McLean, Robert R; Just, Allan C; Schwartz, Joel; Spiro, Avron; Vokonas, Pantel; Amin, Najaf; Ikram, M Arfan; Uitterlinden, Andre G; van Meurs, Joyce B J; Spector, Tim D; Steves, Claire; Baccarelli, Andrea A; Bell, Jordana T; van Duijn, Cornelia M; Fornage, Myriam; Hsu, Yi-Hsiang; Mill, Jonathan; Mosley, Thomas H; Seshadri, Sudha; Deary, Ian J
Cognitive functions are important correlates of health outcomes across the life-course. Individual differences in cognitive functions are partly heritable. Epigenetic modifications, such as DNA methylation, are susceptible to both genetic and environmental factors and may provide insights into individual differences in cognitive functions. Epigenome-wide meta-analyses for blood-based DNA methylation levels at ~420,000 CpG sites were performed for seven measures of cognitive functioning using data from 11 cohorts. CpGs that passed a Bonferroni correction, adjusting for the number of CpGs and cognitive tests, were assessed for: longitudinal change; being under genetic control (methylation QTLs); and associations with brain health (structural MRI), brain methylation and Alzheimer's disease pathology. Across the seven measures of cognitive functioning (meta-analysis n range: 2557-6809), there were epigenome-wide significant (P cognitive function (cg21450381, P = 1.6 × 10 -8 ), and phonemic verbal fluency (cg12507869, P = 2.5 × 10 -9 ). The CpGs are located in an intergenic region on chromosome 12 and the INPP5A gene on chromosome 10, respectively. Both probes have moderate correlations (~0.4) with brain methylation in Brodmann area 20 (ventral temporal cortex). Neither probe showed evidence of longitudinal change in late-life or associations with white matter brain MRI measures in one cohort with these data. A methylation QTL analysis suggested that rs113565688 was a cis methylation QTL for cg12507869 (P = 5 × 10 -5 and 4 × 10 -13 in two lookup cohorts). We demonstrate a link between blood-based DNA methylation and measures of phonemic verbal fluency and global cognitive ability. Further research is warranted to understand the mechanisms linking genomic regulatory changes with cognitive function to health and disease.
Zhang, Ying; Fan, Shuying; Xiang, Yang; Duan, Hua; Sun, Li
This meta-analysis aimed to evaluate the prognosis and recurrence of apparent early-stage ovarian tumors treated with laparoscopy compared with laparotomy. Clinical studies published in English were retrieved from the computerized databases Medline and Embase. A meta-analysis was performed to investigate the differences in the efficacy and safety of laparoscopy versus laparotomy in terms of postoperative complications, lengths of hospital stay, recurrence rates, and disease-free survival times using the random effects model. The studies were independently reviewed by two investigators. Data from the eligible studies were extracted, and the meta-analysis was performed using the Comprehensive Meta-Analysis program, version 2 (CMA-2; Biostat, Englewood, NJ, USA). A total of 8 studies were included in the analysis. The results showed that laparoscopic surgery was significantly associated with lower rates of complications (OR = 0.433, P = 0.019) and shorter postoperative hospital stays (weighted mean difference [WMD] = −0.974, P < 0.001). There was no significant difference in the rates of recurrence (OR = 0.707, P = 0.521) between patients with apparent early-stage ovarian tumors who were treated using laparoscopy and those who underwent laparotomy. No publication bias was detected. Laparoscopic surgery shows favorable prognostic outcomes in terms of postoperative complication rates and postoperative hospital stay durations. Further studies with longer follow-up periods are required to confirm recurrence and survival outcomes after laparoscopic surgery in patients with apparent early-stage ovarian tumors
Murabito, Joanne M.; White, Charles C.; Kavousi, Maryam; Sun, Yan V.; Feitosa, Mary F.; Nambi, Vijay; Lamina, Claudia; Schillert, Arne; Coassin, Stefan; Bis, Joshua C.; Broer, Linda; Crawford, Dana C.; Franceschini, Nora; Frikke-Schmidt, Ruth; Haun, Margot; Holewijn, Suzanne; Huffman, Jennifer E.; Hwang, Shih-Jen; Kiechl, Stefan; Kollerits, Barbara; Montasser, May E.; Nolte, Ilja M.; Rudock, Megan E.; Senft, Andrea; Teumer, Alexander; van der Harst, Pim; Vitart, Veronique; Waite, Lindsay L.; Wood, Andrew R.; Wassel, Christina L.; Absher, Devin M.; Allison, Matthew A.; Amin, Najaf; Arnold, Alice; Asselbergs, Folkert W.; Aulchenko, Yurii; Bandinelli, Stefania; Barbalic, Maja; Boban, Mladen; Brown-Gentry, Kristin; Couper, David J.; Criqui, Michael H.; Dehghan, Abbas; den Heijer, Martin; Dieplinger, Benjamin; Ding, Jingzhong; Doerr, Marcus; Espinola-Klein, Christine; Felix, Stephan B.; Ferrucci, Luigi; Folsom, Aaron R.; Fraedrich, Gustav; Gibson, Quince; Goodloe, Robert; Gunjaca, Grgo; Haltmayer, Meinhard; Heiss, Gerardo; Hofman, Albert; Kieback, Arne; Kiemeney, Lambertus A.; Kolcic, Ivana; Kullo, Iftikhar J.; Kritchevsky, Stephen B.; Lackner, Karl J.; Li, Xiaohui; Lieb, Wolfgang; Lohman, Kurt; Meisinger, Christa; Melzer, David; Mohler, Emile R.; Mudnic, Ivana; Mueller, Thomas; Navis, Gerjan; Oberhollenzer, Friedrich; Olin, Jeffrey W.; O'Connell, Jeff; O'Donnell, Christopher J.; Palmas, Walter; Penninx, Brenda W.; Petersmann, Astrid; Polasek, Ozren; Psaty, Bruce M.; Rantner, Barbara; Rice, Ken; Rivadeneira, Fernando; Rotter, Jerome I.; Seldenrijk, Adrie; Stadler, Marietta; Summerer, Monika; Tanaka, Toshiko; Tybjaerg-Hansen, Anne; Uitterlinden, Andre G.; van Gilst, Wiek H.; Vermeulen, Sita H.; Wild, Sarah H.; Wild, Philipp S.; Willeit, Johann; Zeller, Tanja; Zemunik, Tatijana; Zgaga, Lina; Assimes, Themistocles L.; Blankenberg, Stefan; Campbell, Harry; Boerwinkle, Eric; Cooke, John P.; de Graaf, Jacqueline; Herrington, David; Kardia, Sharon L. R.; Mitchell, Braxton D.; Murray, Anna; Muenzel, Thomas; Newman, Anne B.; Oostra, Ben A.; Rudan, Igor; Shuldiner, Alan R.; Snieder, Harold; van Duijn, Cornelia M.; Voelker, Uwe; Wright, Alan F.; Wichmann, H. -Erich; Wilson, James F.; Witteman, Jacqueline C. M.; Liu, Yongmei; Hayward, Caroline; Borecki, Ingrid B.; Ziegler, Andreas; North, Kari E.; Cupples, L. Adrienne; Kronenberg, Florian; Dorr, M.; Munzel, T.; Volker, U.
Background-Genetic determinants of peripheral arterial disease (PAD) remain largely unknown. To identify genetic variants associated with the ankle-brachial index (ABI), a noninvasive measure of PAD, we conducted a meta-analysis of genome-wide association study data from 21 population-based cohorts.
Küçüktepe, Seval Eminoglu; Yildiz, Nilgün
The purpose of this study is to investigate the gender effect on elementary mathematics and science and technology teachers' opinions regarding curriculum elements which are objectives, content, learning situation and evaluation. Meta-analysis was used in order to analyze data. Two articles, 11 master and one doctorate thesis which were conducted…
Verhaegen, Jorine; Gallos, Ioannis D.; van Mello, Norah M.; Abdel-Aziz, Mohamed; Takwoingi, Yemisi; Harb, Hoda; Deeks, Jonathan J.; Mol, Ben W. J.; Coomarasamy, Arri
Objective To determine the accuracy with which a single progesterone measurement in early pregnancy discriminates between viable and non-viable pregnancy. Design Systematic review and meta-analysis of diagnostic accuracy studies. Data sources Medline, Embase, CINAHL, Web of Science, ProQuest,
Amin Al Olama, Ali; Kote-Jarai, Zsofia; Schumacher, Fredrick R
Genome-wide association studies (GWAS) have identified multiple common genetic variants associated with an increased risk of prostate cancer (PrCa), but these explain less than one-third of the heritability. To identify further susceptibility alleles, we conducted a meta-analysis of four GWAS inc...
Aune, D.; Chan, D.S.; Lau, R.; Vieira, R.; Greenwood, D.C.; Kampman, E.; Norat, T.
OBJECTIVE: To investigate the association between intake of dietary fibre and whole grains and risk of colorectal cancer. DESIGN: Systematic review and meta-analysis of prospective observational studies. DATA SOURCES: PubMed and several other databases up to December 2010 and the reference lists of
Aune, D.; Chan, D.S.M.; Lau, R.; Vieira, R.; Greenwood, D.C.; Kampman, E.; Norat, T.
Objective To investigate the association between intake of dietary fibre and whole grains and risk of colorectal cancer. Design Systematic review and meta-analysis of prospective observational stu