Prevalence and factors for food allergy in different populations from different regions: A protocol for a systematic review and meta-analysis

Background To determine the prevalence of food allergy (FA) and factors associated with these occurrences in different populations from different regions. Materials and methods The literature search will be conducted via Pubmed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), Vip and Wanfang databases. Ratio rate (RR), odds ratio (OR) and 95% confidence intervals (CIs) will be adopted to evaluate prevalence and factors for FA in different populations from different regions. When the heterogeneity is small (I2<50%), the fixed effect model will be analyzed, otherwise, random effects model analysis will be performed. When the heterogeneity is large (I2≥50%), Meta regression will be used to explore the sources of inter-study heterogeneity. When the heterogeneity is large (I2≥50%) and the results are statistically significant (P<0.05), subgroup analysis will be analyzed based on age, gender, race/region, literature quality and other factors. Funnel plots will be used to reflect reporting bias and the Begg’s test will be used to test the symmetry of the funnel plots. When publication bias occurs, “cut-and-fill” method will be adopted to adjust publication bias. And sensitivity analysis will be performed for all outcome indicators. Discussion This meta-analysis will evaluate the prevalence of FA and factors associated with these occurrences in different populations from different regions on the basis of existing evidences. Our study may be crucial to analyze similarities and differences regarding FA between different individuals from diverse regions and eventually define preventive or diagnostic approaches specifically tailored to certain populations and regions. Systematic review registration OSF registration number: 10.17605/OSF.IO/VQXU9

Association Between MTHFD1 1958G > A Variant and non-Syndromic Cleft lip and Palate: An Updated Meta-Analysis

Introduction Non-syndromic cleft lip and palate (NSCLP) is one of the most common and challenging congenital deformities worldwide. Previous research has linked the methylenetetrahydrofolate dehydrogenase1 (MTHFD1) gene to orofacial cleft (OFC) susceptibility via a complex metabolism. Studies analyzing the MTHFD1 1958G > A variant and NSCLP are contradictory. This study aims to evaluate the association between the MTHFD1 1958G > A variant and NSCLP by meta-analysis. Methods PubMed, Web of Science, MEDLINE, and Google Scholar databases were searched to retrieve the eligible studies. A fixed- or random-effect model was used to calculate pooled odds ratio (OR) and 95% confidence interval (CI). All analyses were calculated by Metagenyo software. To detect heterogeneity, the Cochrane Q and I2 statistics were used. The publication bias was estimated using funnel plots and Egger’s test. Results Our study suggested that the MTHFD1 1958G > A variant allele “A” does not appear to increase the risk of NSCLP (A vs G random effect model: Overall P = .501, OR = 1.07, CI = 0.88–1.31; Asians P = .245, OR = 1.29, CI = 0.84–1.97; Caucasians P = .658, OR = 0.95, CI = 0.76–1.19). Similarly, mutant genotypes also did not exhibit increased risk for NSCLP in the overall populations as well in subgroup analysis by ethnicity (AA + AG vs GG: Overall P = .684, OR = 1.06, CI = 0.80–1.39; Asians P = .240, OR = 1.47, CI = 0.77–2.78; Caucasians P = .923, OR = 0.99, CI = 0.85–1.16). Conclusions Our data suggest no association between the MTHFD1 1958G > A variant and NSCLP. Additional well-designed studies are needed to better understand the role of MTHFD1 polymorphisms in the etiopathogenesis of NSCLP.

Nutritional status of children living within institution-based care: a retrospective analysis with funnel plots and control charts for programme monitoring

ObjectivesThe aim of this study is to fill a key information gap on the nutrition-related epidemiology of orphaned and vulnerable children living within institution-based care (IBC) across six countries.DesignA retrospective analysis with Shewhart control charts and funnel plots to explore intersite and over time variations in nutritional status.SettingWe conducted a retrospective analysis of records from Holt International’s Child Nutrition Programme from 35 sites in six countries; Mongolia, India, Ethiopia, Vietnam, China and the Philippines.ParticipantsDeidentified health records from Holt International’s online nutrition screening database included records from 2926 children, 0–18 years old. Data were collected from 2013 to 2020 and included demographic and health information.ResultsAt initial screening, 717 (28.7%) children were anaemic, 788 (34.1%) underweight, 1048 (37.3%) stunted, 212 (12.6%) wasted, 135 (12%) overweight or obese and 339 (31%) had small head circumference. Many had underlying conditions: low birth weight, 514 (57.5%); prematurity, 294 (42.2%) and disabilities, 739 (25.3%). Children with disabilities had higher prevalence of malnutrition compared with counterparts without disabilities at baseline and 1-year screenings. There was marked intersite variation. Funnel plots highlight sites with malnutrition prevalence outside expected limits for this specific population taking into consideration natural variation at baseline and at 1 year. Control charts show changes in site mean z-scores over time in relation to site control limits.ConclusionsMalnutrition is prevalent among children living within IBC, notably different forms of undernutrition (stunting, underweight, wasting). Underlying risk factors are also common: prematurity, low birth weight and disability. Nutrition interventions should take into account the needs of this vulnerable population, especially for infants and those with disabilities. Using control charts to present data could be especially useful to programme managers as sites outside control limits could represent: problems to be investigated; good practices to be shared.

Funnel Plots for Assessing Institutional Performance

<p>This thesis presents a comparison of maternal outcomes for births in New Zealand District Health Boards (DHBs).This is carried out through analysis of the National Minimum Dataset collected by the Ministry of Health for 2007. The outcome compared is postpartum haemorrhage (PPH) the results are displayed using funnel plots, a useful tool for displaying unbiased information on performance outcomes when comparing institutions. Exploration of the data found that there are differences in the demographics, maternal and birth characteristics among DHBs. The rates of PPH are different and the population mixes are made up of a range of different proportions of ethnic groups, ages and deprivation indexes. The exploratory analysis found that a large number of factors are associated with PPH. And that birth weight, parity and gestation had a large number of missing observations. These factors are not missing at random and require imputing prior to constructing the funnel plots. Results show that there is divergence amongst DHBs in the postpartum haemorrhage rate. First a raw PPH rate was plotted and the results indicated there were differences among DHBs. As there are many potential predictors for PPHa logistic regression model was applied to find the most important factors related to PPH. This allows us to apply an adjusted rate for the funnel plot. The risk adjusted funnel plot also indicated differences among DHBs. Two approaches are taken to account for the overdispersion. A winsorised estimate and a winsorised estimate with a random effects term are applied to the data. The approaches produced different results. The winsorised estimate widened the control limits and the random effects term narrowed the control limits. All four plots identified an extreme outlier and this was later removed from the analysis and the winsorisation funnel plots were rerun. The influential outlier made a difference and from this we can concluded that 2 out 20 DHBs lie outside the 95% control limits. These two DHBs could be stated as having a very low rate of PPH.</p>

Funnel Plots for Assessing Institutional Performance

<p>This thesis presents a comparison of maternal outcomes for births in New Zealand District Health Boards (DHBs).This is carried out through analysis of the National Minimum Dataset collected by the Ministry of Health for 2007. The outcome compared is postpartum haemorrhage (PPH) the results are displayed using funnel plots, a useful tool for displaying unbiased information on performance outcomes when comparing institutions. Exploration of the data found that there are differences in the demographics, maternal and birth characteristics among DHBs. The rates of PPH are different and the population mixes are made up of a range of different proportions of ethnic groups, ages and deprivation indexes. The exploratory analysis found that a large number of factors are associated with PPH. And that birth weight, parity and gestation had a large number of missing observations. These factors are not missing at random and require imputing prior to constructing the funnel plots. Results show that there is divergence amongst DHBs in the postpartum haemorrhage rate. First a raw PPH rate was plotted and the results indicated there were differences among DHBs. As there are many potential predictors for PPHa logistic regression model was applied to find the most important factors related to PPH. This allows us to apply an adjusted rate for the funnel plot. The risk adjusted funnel plot also indicated differences among DHBs. Two approaches are taken to account for the overdispersion. A winsorised estimate and a winsorised estimate with a random effects term are applied to the data. The approaches produced different results. The winsorised estimate widened the control limits and the random effects term narrowed the control limits. All four plots identified an extreme outlier and this was later removed from the analysis and the winsorisation funnel plots were rerun. The influential outlier made a difference and from this we can concluded that 2 out 20 DHBs lie outside the 95% control limits. These two DHBs could be stated as having a very low rate of PPH.</p>

Meta-analysis of coagulation disbalances in COVID-19: 41 studies and 17601 patients

Introduction. Coagulation parameters are important determinants for COVID-19 infection. We conducted meta-analysis to assess the early hemostatic parameters in retrospective studies in association with severity of infection. Methods. Ovid, PubMed, Web of Sciences, and Google Scholar were searched for research articles that addressed clinical characteristics of COVID-19 patients and disease severity. Results were filtered using exclusion and inclusion criteria and then pooled into a meta-analysis to estimate the standardized mean difference with 95% CI for each of five coagulation parameters (D-dimers, fibrinogen, prothrombin time, platelets count, activated partial thromboplastin time). Two authors independently extracted data and assessed study quality. To explore the heterogeneity and robustness of our fundings, sensitivity and subgroup analyses were conducted. Publication bias was assessed with contour-enhanced funnel plots and Egger test by linear regression. Results. Overall, 41 original studies (17601 patients) on SARS-CoV2 were included. For the two groups of patients, stratified by severity, we identified that D-dimers, fibrinogen, activated partial thromboplastin time, and prothrombin time were significantly higher in the severe group (SMD 0.6985 with 95%CI [0.5155; 0.8815]); SMD 0.661with 95%CI [0.3387; 0.9833]; SMD 0.2683 with 95%CI [0.1357; 0.4009]; SMD 0.284 with 95%CI [0.1472; 0.4208]). In contrast, PLT was significantly lower in patients with more severe cases of COVID-19 (SMD -0.1684 with 95%CI [-0.2826; -0.0542]). Neither the analysis by the leave-one-out method nor the influence diagnostic have identified studies that solely cause significant change in the effect size estimates. Subgroup analysis showed no significant difference between articles originated from different countries but revealed that severity assessment criteria might have influence over estimated effect sizes for platelets and D-dimers. Contour-enhanced funnel plots and the Egger test for D-dimers and fibrinogen revealed significant asymmetry that might be a sign of publication bias. Conclusions. The standard coagulation laboratory parameters with exception of platelets counts are significantly elevated in patients with severe COVID-19. However, fibrinolysis shutdown requires evaluation outside conventional coagulation tests and analysis of additional specific markers related to clotting formation and PLT characteristics. We hypothesize that a proportion and parameters of immature reticulated platelets may serve as additional biomarkers for prediction of adverse events.

Prevalence of burnout among university students in low- and middle-income countries: A systematic review and meta-analysis

Background Burnout is common among university students and may adversely affect academic performance. Little is known about the true burden of this preventable malady among university students in low-and-middle-income countries (LMICs). Objectives This study aimed to systematically estimate the prevalence of burnout among university students in LMICs. Methods We searched PubMed, Google Scholar, CINAHL, Web of Science, African Journals Online, and Embase from the inception of each database until February 2021. Original studies were included. No study design or language restrictions were applied. A random-effects meta-analysis was performed using STATA version 16.0. Heterogeneity and publication bias were assessed using Q-statistics and funnel plots, respectively. Results Fifty-five unique articles, including a total of 27,940 (Female: 16,215, 58.0%) university students from 24 LMICs were included. The Maslach Burnout Inventory (MBI) was used in 43 studies (78.2%). The pooled prevalence of burnout was 12.1% (95% Confidence Interval (CI) 11.9–12.3; I2 = 99.7%, Q = 21,464.1, p = < 0.001). The pooled prevalence of emotional exhaustion (feelings of energy depletion), cynicism (negativism), and reduced professional efficacy were, 27.8% (95% CI 27.4–28.3; I2 = 98.17%. p = <0.001), 32.6 (95% CI: 32.0–33.1; I2: 99.5%; p = < 0.001), and 29.9% (95% CI: 28.8–30.9; I2: 98.1%; p = < 0.001), respectively. Conclusion Nearly one-third of university students in LMICs experience burnout. More studies are needed to understand the causes of burnout in this key population. There is a need to validate freely available tools for use in these countries.

The effect of 0.01% atropine on ocular axial elongation for myopia children: a meta-analysis

Objectives: This meta-analysis aimed to identify the therapeutic effect of 0.01% atropine with on ocular axial elongation for myopia children. Methods: We searched PubMed, Cochrane Library, and CBM databases from inception to July 2021. Meta-analysis was conducted using STATA version 14.0 and Review Manager version 5.3 softwares. We calculated the weighted mean differences(WMD) to analyze the change of ocular axial length (AL) between orthokeratology combined with 0.01% atropine (OKA) and orthokeratology (OA) alone. The Cochran's Q-statistic and I2 test were used to evaluate potential heterogeneity between studies. To evaluate the influence of single studies on the overall estimate, a sensitivity analysis was performed. We also performed sub group and meta-regression analyses to investigate potential sources of heterogeneity. We conducted Begger's funnel plots and Egger's linear regression tests to investigate publication bias. Results: Nine studies that met all inclusion criteria were included in this meta-analysis. A total of 191 children in OKA group and 196 children in OK group were assessed. The pooled summary WMD of AL change was -0.90(95%CI=-1.25~-0.55) with statistical significance(t=-5.03, p<0.01), which indicated there was obvious difference between OKA and OK in myopic children. Subgroup analysis also showed that OKA treatment resulted in significantly less axial elongation compared to OK treatment alone according to SER. We found no evidence for publication bias. Conclusions: Our meta-analysis indicates 0.01% atropine atropine is effective in slowing axial elongation in myopia children with orthokeratology.

The Volume Alterations of the Amygdala in Autism Spectrum Disorder: A Meta-Analysis on MRI Study

Background:Due to the unclear etiology and pathogenesis of autism spectrum disorder (ASD), there is still a lack of effective drugs for prevention and treatment of ASD, which can improve the prognosis of autism through early intervention. However, the current diagnostic methods are mainly based on qualitative indicators such as behavioral standards, which cannot timely and accurately diagnose autism. A large number of studies have found abnormal amygdala volume in autism patients.This study aimed to evaluate amygdala volume in patients with ASD and elucidat the potential relationship between amygdala volume and ASD by using systematic review and meta-analysis, with a view to providing a new approach for early diagnosis of ASD. Methods: Comprehensive electronic search in Pubmed, Web of Science, EBSCOhost, Embase, the Cochrane Review Library, CNKI and WanFang data to find original articles about the relationship between amygdala volume and the ASD. Heterogeneity across studies were assessed using I2 and Q statistics. Random-effects model was used to estimate the odds ratios (ORs) with 95% confidence intervals (CIs). Sensitivity analyses to assess the influence of individual studies on the pooled estimate. Publication bias was investigated using funnel plots and Egger's regression test. If the funnel plot is asymmetry, the reason is distinguished by using the contour-enhanced funnel plots and trim-and-fill method. Results: The results showed that the volume of the right amygdala significantly increased in patients with ASD (WMD: 0.137, 95% CI: [0.051, 0.222], Z = 3.132, P < 0.001). Subgroup analysis by age showed that the volume of the left amygdala significantly increased in young child patients with ASD (MD: 0.153, 95% CI: [0.025, 0.281], Z = 2.341, P < 0.05), but not change in child (MD: 0.153, 95% CI: [-0.026, 0.332], Z = 1.672, P > 0.05), adolescent (MD: 0.095, 95% CI: [-0.189, 0.379], Z = 0.654, P > 0.05) and adult (MD: 0.068, 95% CI: [-0.103, 0.240], Z = 0.781, P > 0.05) ASD patient. The volume of the right amygdala significantly increased in young child (MD: 0.174, 95% CI: [0.043, 0.304], Z = 2.60, P < 0.05) and child patients(MD: 0.192, 95% CI: [0.040, 0.343], Z = 2.480, P < 0.05) with ASD, but not change in adolescent (MD: 0.208, 95% CI: [-0.201, 0.618], Z = 0.998, P > 0.05) and adulthood patients (MD: 0.126, 95% CI: [-0.040, 0.291], Z = 1.488, P > 0.05). Subgroup analysis by gender showed that the volume of the left amygdala not change in male (MD: 0.101, 95% CI: [-0.031, 0.233], Z = 1.498, P > 0.05) and female group (MD: 0.067, 95% CI: [-0.023, 0.157], Z = 1.452, P > 0.05). The volume of the right amygdala significantly increased in female group (MD: 0.099, 95% CI: [0.019, 0.178], Z = 2.439, P < 0.05), but not change in male group (MD: 0.117, 95% CI: [-0.014, 0.248], Z = 1.755, P > 0.05).Conclusions: The volume of the amygdala significantly increased in young children with ASD. These findings suggest that the volume of the amygdala in young children might be a potential early auxiliary imaging diagnosis method of ASD.

The Impact of Foot Orthoses and Exercises on Pain and Navicular Drop for Adult Flatfoot: A Network Meta-Analysis

Background: Adult flatfoot leads to injury and decreased quality of life. The most widely applied noninvasive approaches are wearing foot orthoses or exercising. Both interventions raise controversy about reducing pain and neutralizing foot posture. This study investigated the impact of foot orthoses and exercise on pain and navicular drop (present for foot posture). Methods: Four databases were used: MEDLINE, PubMed, Web of Science, and Cochrane, from the earliest records to November 2020. Randomized controlled studies focused on adult flatfoot that evaluated the effect of exercise and foot orthoses on pain and navicular drop were extracted. We used data analysis to estimate the relative effect of heterogeneity using I2 and publication bias using funnel plots. Results: Ten studies were identified through to November 2020. Active interventions (AIs) were exercise and exercise combined with foot orthoses; passive interventions (PIs) were foot orthoses and added stretching. Both AIs and PIs decreased pain significantly (SMD −0.94, 95% CI −1.35, −0.54 and SMD −1.4, 95% CI −1.87, −0.92). The AIs reduced pain level better than PIs. Controversially, no treatment was found to affect navicular drop. Conclusion: Both exercise and foot orthoses can reduce pain but not realign foot posture. Exercise alone or combined with foot orthoses showed a better effect on adult flatfoot than only wearing foot orthoses. Active intervention was shown to have better efficacy in reducing pain than passive intervention.