Funnel plots may show asymmetry in the absence of publication bias with continuous outcomes dependent on baseline risk: presentation of a new publication bias test

Susceptibility of Foodborne Pathogens to Milk-Origin Lactic Acid Bacteria Supernatants: A Comprehensive Meta-Regression Study

This systematic review and meta-analysis compile the in vitro antimicrobial efficacy of lactic acid bacteria (LAB) supernatants against three common pathogenic bacteria found in dairy products: Salmonella spp., L. monocytogenes, and Staphylococcus aureus. After screening and analysis of full papers, identified by searches in PubMed, Scopus, and Web of Science databases, thirty-nine studies were regarded as relevant, and a total of 510 observations were recorded. The effects of moderators on inhibition diameters were assessed by adjusting three pathogen-specific meta-regression models. Results showed that, in general terms, strains from the Enterococcus genus displayed the highest inhibition values against L. monocytogenes (15.90 ± 2.138 mm), whereas Lacticaseibacillus strains were more effective against S. aureus (11.89 ± 0.573 mm). The well diffusion test outperformed the spot and disk diffusion tests, and more acidic LAB supernatants resulted in higher measurements of inhibition diameters (p < 0.001). Meta-regression models incorporating LAB genus, pathogen concentration, and incubation time explained 33.8%, 52.3%, and 19.8% of the total variance in inhibition diameters for L. monocytogenes, Salmonella spp., and S. aureus, respectively. None of the three models showed evidence of publication bias. This meta-regression study demonstrated that LAB strains present in dairy products possess a variable capacity to inhibit any of the three foodborne pathogens. Overall, L. monocytogenes was found to exhibit greater susceptibility than Salmonella spp. and S. aureus; thus, the antilisterial capacity of the selected LAB strains could be exploited in developing biocontrol strategies for cheese-making.

The effects of radiofrequency exposure on male fertility: A systematic review of human observational studies with dose-response meta-analysis

BACKGROUND

The World Health Organization (WHO) is bringing together evidence on radiofrequency electromagnetic field (RF-EMF) exposure in relation to health outcomes, previously identified as priorities for research and evaluation by experts in the field, to inform exposure guidelines. A suite of systematic reviews have been undertaken by a network of topic experts and methodologists to collect, assess and synthesise data relevant to these guidelines. Following the WHO handbook for guideline development and the COSTER conduct guidelines, we systematically reviewed the evidence on the potential effects of RF-EMF exposure on male fertility in human observational studies.

METHODS

We conducted a broad and sensitive search for potentially relevant records within the following bibliographic databases: MEDLINE; Embase; Web of Science and EMF Portal. We also conducted searches of grey literature through relevant databases including OpenGrey, and organisational websites and consulted RF-EMF experts. We hand searched reference lists of included study records and for citations of these studies. We included quantitative human observational studies on the effect of RF-EMF exposure in adult male participants on infertility: sperm concentration; sperm morphology; sperm total motility; sperm progressive motility; total sperm count; and time to pregnancy. Titles and abstracts followed by full texts were screened in blinded duplicate against pre-set eligibility criteria with consensus input from a third reviewer as required. Data extraction from included studies was completed by two reviewers, as was risk of bias assessment using the Office of Health Assessment and Translation (OHAT) tool. We conducted a dose-response meta-analysis as possible and appropriate. Certainty of the evidence was assessed by two reviewers using the OHAT GRADE tool with input from a third reviewer as required.

RESULTS

We identified nine studies in this review; seven were general public studies (with the general public as the population of interest) and two were occupational studies (with specific workers/workforces as the population of interest). General public studies. Duration of phone use: The evidence is very uncertain surrounding the effects of RF-EMF on sperm concentration (10/6 mL) (MD (mean difference) per hour of daily phone use 1.6 106/mL, 95 % CI -1.7 to 4.9; 3 studies), sperm morphology (MD 0.15 percentage points of deviation of normal forms per hour, 95 % CI -0.21 to 0.51; 3 studies), sperm progressive motility (MD -0.46 percentage points per hour, 95 % CI -1.04 to 0.13; 2 studies) and total sperm count (MD per hour -0.44 106/ejaculate, 95 % CI -2.59 to 1.7; 2 studies) due to very low-certainty evidence. Four additional studies reported on the effect of mobile phone use on sperm motility but were unsuitable for pooling; only one of these studies identified a statistically significant effect. All four studies were at risk of exposure characterisation and selection bias; two of confounding, selective reporting and attrition bias; three of outcome assessment bias and one used an inappropriate statistical method. Position of phone: There may be no or little effect of carrying a mobile phone in the front pocket on sperm concentration, total count, morphology, progressive motility or on time to pregnancy. Of three studies reporting on the effect of mobile phone location on sperm total motility and, or, total motile count, one showed a statistically significant effect. All three studies were at risk of exposure characterisation and selection bias; two of confounding, selective reporting and attrition bias; three of outcome assessment bias and one used inappropriate statistical method. RF-EMF Source: One study indicates there may be little or no effect of computer or other electric device use on sperm concentration, total motility or total count. This study is at probably high risk of exposure characterisation bias and outcome assessment bias. Occupational studies. With only two studies of occupational exposure to RF-EMF and heterogeneity in the population and exposure source (technicians exposed to microwaves or seamen exposed to radar equipment), it was not plausible to statistically pool findings. One study was at probably or definitely high risk of bias across all domains, the other across domains for exposure characterisation bias, outcome assessment bias and confounding.

DISCUSSION

The majority of evidence identified was assessing localised RF-EMF exposure from mobile phone use on male fertility with few studies assessing the impact of phone position. Overall, the evidence identified is very uncertain about the effect of RF-EMF exposure from mobile phones on sperm outcomes. One study assessed the impact of other RF-EMF sources on male fertility amongst the general public and two studies assessed the impact of RF-EMF exposure in occupational cohorts from different sources (radar or microwave) on male fertility. Further prospective studies conducted with greater rigour (in particular, improved accuracy of exposure measurement and appropriate statistical method use) would build the existing evidence base and are required to have greater certainty in any potential effects of RF-EMF on male reproductive outcomes. Prospero Registration: CRD42021265401 (SR3A).

Meta-analysis of Circulatory mitomiRs in stress Response: Unveiling the significance of miR-34a and miR-146a

BACKGROUND

MicroRNAs (miRNAs) are short, noncoding RNAs with essential roles in cellular pathways and are often associated with various diseases and stress conditions. Recently, they have been discovered in mitochondria, termed "mitomiRs," with unique functions. Mitochondria, crucial organelles for energy production and stress responses, Dysregulated mitomiRs functions and expression has been evident in stress conditions such as cardiovascular and neurodegenerative. In this meta-analysis we have systematically identified miR-34a & miR-146a as possible potential biomarkers for affliction.

METHODS

A meta-analysis was conducted to assess the potential role of miR-34a and miR-146a, two specific mitomiRs, as biomarkers in stress-related conditions. The study followed PRISMA guidelines, involving comprehensive database searches in May and September 2023. Twelve studies meeting predefined inclusion criteria were selected, and data analysis included the evaluation of miR-34a and miR-146a expression levels in various stress conditions compared to control groups. We also performed Gene ontology (GO) and Pathway enrichment analysis to observe how mitomiRs affects our body.

RESULTS

The meta-analysis revealed a significant increase in overall mitomiRs (miR-34a and miR-146a) expression levels in experimental groups experiencing different stress conditions compared to control groups (Z = 3.54, p < 0.05 using RevMan software). miR-34a demonstrated more pronounced upregulation and exhibited potential as a specific biomarker in certain stress-related conditions (Z = 2.22, p < 0.05). However, miR-146a did not show a significant difference, requiring further investigation in various stress-related contexts. The Analysis indicated a high degree of heterogeneity among the studies.

CONCLUSION

This meta-analysis emphasises the importance of mitomiRs, especially miR-34a, as potential biomarkers in the intricate interplay between stress, mitochondrial function, and disease. The study opens new avenues for exploring miRNAs' diagnostic and therapeutic applications in stress-related diseases, highlighting their pivotal role at the crossroads of molecular biology, psychology, and medicine.

Effects of resveratrol on the anthropometric indices and inflammatory markers: an umbrella meta-analysis

BACKGROUND

The evidence for resveratrol's anti-obesity and anti-inflammatory qualities is accumulating, though meta-analyses have reported mixed results. The current umbrella meta-analysis aimed to assess the present evidence and provide an accurate estimate of the overall effects of resveratrol on the anthropometric indices and inflammatory markers.

METHOD

The Web of Science, PubMed, Scopus, and Google Scholar databases were searched till March 2023. The meta-analysis was performed utilizing a random-effects model. Moreover, the overall strength and quality of the evidence were assessed using the GRADE tool.

RESULTS

The results from 19 meta-analyses investigating 81 unique randomized controlled trials with 4088 participants revealed that resveratrol supplementation reduced the body mass index (ES =  - 0.119, 95% CI (- 0.192, - 0.047), p = 0.001), waist circumference (ES =  - 0.405, 95% CI [- 0.664, - 0.147], p = 0.002), serum levels of C-reactive protein (ES =  - 0.390, 95% CI [- 0.474, - 0.306], p < 0.001), and tumor necrosis factor-α (ES =  - 0.455, 95% CI [- 0.592, - 0.318], p < 0.001) in comparison to the control group. The effects of resveratrol on body weight and Interleukin-6 levels of participants were not significant. However, resveratrol administration significantly decreased body weight in trials with intervention duration ≥ 12 weeks [ES =  - 0.160, 95% CI (- 0.268, - 0.052)] and supplement dosage ≥ 500 mg/day [ES =  - 0.130, 95% CI (- 0.238, - 0.022)].

CONCLUSION

The findings suggest the beneficial effects of resveratrol supplementation on reducing general and central obesity, as well as decreasing some inflammatory markers. Nevertheless, further high-quality research is required to prove these achievements and also evaluate resveratrol's effects on other inflammatory markers.

The efficacy of curcumin in relieving osteoarthritis: A meta-analysis of meta-analyses

Osteoarthritis (OA) is one of the most prevalent degenerative joint diseases. Several meta-analyses have shown that curcumin could improve the function of the knee and alleviate pain in OA, while some meta-analyses demonstrate controversial results. Hence, we assessed curcumin's effects on knee OA in an umbrella meta-analysis. PubMed, Scopus, Embase, and Web of Science databases were employed to find English-language meta-analyses of randomized controlled trials investigating the effect of curcumin supplementation on OA outcomes up to September 2023. The visual analog scale (VAS), Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain, function, and stiffness scales were analyzed. Effect sizes and 95% confidence intervals were utilized to obtain the overall effect size. A random-effects model was applied to perform the meta-analysis. Heterogeneity was determined by I2 statistics and the Cochrane Q-test. The pooled effect of the 11 included meta-analyses showed that curcumin could significantly decrease the VAS score (weighted mean difference [WMD] and standardized mean difference [SMD]), WOMAC-total (SMD and WMD), WOMAC-Function (SMD and WMD), WOMAC-Pain (SMD), and WOMAC-Stiffness scores (SMD) (p ≤ 0.001, ≤0.001, ≤0.001, 0.007, ≤0.001, 0.002, ≤0.001, ≤0.001, respectively). The results strongly support curcuminoid supplementation in relieving pain, improving joint mobility and stiffness, and shortening medication usage of OA patients.

Folate supplementation as a beneficial add-on treatment in relieving depressive symptoms: A meta-analysis of meta-analyses

The results of meta-analyses investigating the role of folate on depression are conflicting. The aim of this umbrella meta-analysis was to obtain an overall effect and give a concise and resolving conclusion. International scientific databases including PubMed, Scopus, and Web of Science were searched up to Oct 2023. All observational and interventional meta-analyses investigating the role of folate in depression were included in the study. Random-effects model was employed to obtain pooled results. I 2 statistics and Cochrane Q test were used to assess the between-study heterogeneity. The quality of included meta-analyses was evaluated using the Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR2) questionnaire. Overall 11 studies were included, of which 8 studies went under quantitative evaluation. The results indicated that folate supplementation significantly relieved depression symptoms [(SMD: -0.42; 95% CI: -0.57, -0.27, p < .001; I 2 = 0.0%, p-heterogeneity = 0.554) (WMD: -3.20; 95% CI: -4.00, -2.41, p < .001, I 2 = 14.8%, p-heterogeneity = 0.318)] with low levels of heterogeneity. Also, based on observational studies, folate insufficiency significantly increased the odds ratio of depression by 35% (OR:1.35; 95% CI: 1.27, 1.42, p < .001, I 2 = 8.7%, p-heterogeneity = 0.350). The findings support the fact that folate supplementation could be suggested as an efficacious and adjuvant agent in the alleviation of depression symptoms along with routine medications.

Iron deficiency anemia status in Iranian pregnant women and children: an umbrella systematic review and meta-analysis

BACKGROUND

Iron deficiency anemia (IDA) is a global health challenge, especially affecting females and children. We aimed to conduct an umbrella systematic review of available evidence on IDA's prevalence in Iranian pregnant women and children.

METHODS

We searched the Web of Science, Science Direct, PubMed, Scopus, and Google Scholar databases for articles published by April 2023. Meta-analyses investigating the status of IDA in Iran were included. The findings of seven meta-analyses comprising 189,627 pregnant women with a mean age of 26 and 5,890 children under six years old were included in this study. The methodological quality of each study was evaluated with the Assessment of Multiple Systematic Reviews (AMSTAR2) instrument.

RESULTS

We estimated the prevalence of IDA at 15.71% in pregnant women and 19.91% in young children. According to our subgroup analysis of pregnant women, IDA's prevalence in urban and rural regions was 16.32% and 12.75%; in the eastern, western, central, southern, and northern regions of Iran, it was estimated at 17.8%, 7.97%, 19.97%, 13.45%, and 17.82%, respectively.

CONCLUSION

IDA is common in young children and pregnant females and is a significant public health concern in Iran. The present umbrella review results estimated that Iran is in the mild level of IDA prevalence based on WHO classification. However, due to sanctions and high inflation in Iran, the prevalence of anemia is expected to increase in recent years. Multi-sectoral efforts are required to improve the iron status of these populations and reduce the burden of IDA in the country.

Longitudinal Meta-Analysis of Peak Height Velocity in Young Female Athletes

Growth patterns and biological milestones in youth sports are key to interpreting the development of young athletes. However, there is no analysis of longitudinal meta-analysis describing the growth of young female athletes. This longitudinal meta-analysis estimated growth curves and age at peak height velocity (PHV) in young female athletes based on anthropometric data from longitudinal studies found in the literature. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, studies with repeated measurements in young female athletes were identified from searches of four databases (MEDLINE, Web of Science, SCOPUS, and SPORTDiscus) without date restrictions through August 2023. We adapted our bias assessment criteria using the Cochrane risk of bias tool for randomized controlled trials as a reference. Bayesian multilevel modeling was used to perform a longitudinal meta-analysis to extract stature growth curves and age at PHV. Fourteen studies met our eligibility criteria. Twenty-one independent samples could be included in the analysis. Conditional on the data and models, the predicted mean age at PHV for female athletes was 11.18 years (90% CI: 8.62; 12.94). When studies were aggregated by sport in the models, the models could not capture sport-specific growth curves for stature and estimate a corresponding age at PHV. We provide the first longitudinal meta-analytic summary of pubertal growth and derive age at PHV in young female athletes. The meta-analysis predicted that age at PHV occurs at similar ages to those in the general pediatric population. The data pool was limited in sports and geographic distribution, emphasizing the need to promote longitudinal research in females across different youth sports contexts.

Appendectomy versus antibiotic treatment for acute appendicitis

BACKGROUND

Acute appendicitis is one of the most common emergency general surgical conditions worldwide. Uncomplicated/simple appendicitis can be treated with appendectomy or antibiotics. Some studies have suggested possible benefits with antibiotics with reduced complications, length of hospital stay, and the number of days off work. However, surgery may improve success of treatment as antibiotic treatment is associated with recurrence and future need for surgery.

OBJECTIVES

To assess the effects of antibiotic treatment for uncomplicated/simple acute appendicitis compared with appendectomy for resolution of symptoms and complications.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and two trial registers (World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov) on 19 July 2022. We also searched for unpublished studies in conference proceedings together with reference checking and citation search. There were no restrictions on date, publication status, or language of publication.

SELECTION CRITERIA

We included parallel-group randomised controlled trials (RCTs) only. We included studies where most participants were adults with uncomplicated/simple appendicitis. Interventions included antibiotics (by any route) compared with appendectomy (open or laparoscopic).

DATA COLLECTION AND ANALYSIS

We used standard methodology expected by Cochrane. We used GRADE to assess the certainty of evidence for each outcome. Primary outcomes included mortality and success of treatment, and secondary outcomes included number of participants requiring appendectomy in the antibiotic group, complications, pain, length of hospital stay, sick leave, malignancy in the antibiotic group, negative appendectomy rate, and quality of life. Success of treatment definitions were heterogeneous although mainly based on resolution of symptoms rather than incorporation of long-term recurrence or need for surgery in the antibiotic group.

MAIN RESULTS

We included 13 studies in the review covering 1675 participants randomised to antibiotics and 1683 participants randomised to appendectomy. One study was unpublished. All were conducted in secondary care and two studies received pharmaceutical funding. All studies used broad-spectrum antibiotic regimens expected to cover gastrointestinal bacteria. Most studies used predominantly laparoscopic surgery, but some included mainly open procedures. Six studies included adults and children. Almost all studies aimed to exclude participants with complicated appendicitis prior to randomisation, although one study included 12% with perforation. The diagnostic technique was clinical assessment and imaging in most studies. Only one study limited inclusion by sex (male only). Follow-up ranged from hospital admission only to seven years. Certainty of evidence was mainly affected by risk of bias (due to lack of blinding and loss to follow-up) and imprecision. Primary outcomes It is uncertain whether there was any difference in mortality due to the very low-certainty evidence (Peto odds ratio (OR) 0.51, 95% confidence interval (CI) 0.05 to 4.95; 1 study, 492 participants). There may be 76 more people per 1000 having unsuccessful treatment in the antibiotic group compared with surgery, which did not reach our predefined level for clinical significance (risk ratio (RR) 0.91, 95% CI 0.87 to 0.96; I2 = 69%; 7 studies, 2471 participants; low-certainty evidence). Secondary outcomes At one year, 30.7% (95% CI 24.0 to 37.8; I2 = 80%; 9 studies, 1396 participants) of participants in the antibiotic group required appendectomy or, alternatively, more than two-thirds of antibiotic-treated participants avoided surgery in the first year, but the evidence is very uncertain. Regarding complications, it is uncertain whether there is any difference in episodes of Clostridium difficile diarrhoea due to very low-certainty evidence (Peto OR 0.97, 95% CI 0.24 to 3.89; 1 study, 1332 participants). There may be a clinically significant reduction in wound infections with antibiotics (RR 0.25, 95% CI 0.09 to 0.68; I2 = 16%; 9 studies, 2606 participants; low-certainty evidence). It is uncertain whether antibiotics affect the incidence of intra-abdominal abscess or collection (RR 1.58, 95% CI 0.61 to 4.07; I2 = 19%; 6 studies, 1831 participants), or reoperation (Peto OR 0.13, 95% CI 0.01 to 2.16; 1 study, 492 participants) due to very low-certainty evidence, mainly due to rare events causing imprecision and risk of bias. It is uncertain if antibiotics prolonged length of hospital stay by half a day due to the very low-certainty evidence (MD 0.54, 95% CI 0.06 to 1.01; I2 = 97%; 11 studies, 3192 participants). The incidence of malignancy was 0.3% (95% CI 0 to 1.5; 5 studies, 403 participants) in the antibiotic group although follow-up was variable. Antibiotics probably increased the number of negative appendectomies at surgery (RR 3.16, 95% CI 1.54 to 6.49; I2 = 17%; 5 studies, 707 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Antibiotics may be associated with higher rates of unsuccessful treatment for 76 per 1000 people, although differences may not be clinically significant. It is uncertain if antibiotics increase length of hospital stay by half a day. Antibiotics may reduce wound infections. A third of the participants initially treated with antibiotics required subsequent appendectomy or two-thirds avoided surgery within one year, but the evidence is very uncertain. There were too few data from the included studies to comment on major complications.

Folic acid supplementation on inflammation and homocysteine in type 2 diabetes mellitus: systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The beneficial effects of folate have been observed under different conditions, but the available evidence on inflammation and reduction of cardiovascular disease (CVD) in type 2 diabetes mellitus (T2DM) is limited. The study aimed to explore the effects of folate on inflammation and homocysteine amongst individuals with T2DM.

METHODS

PubMed, Scopus, and Cochrane Library were used to search for evidence. A random-effect model meta-analysis through Review Manager (version 5.4) and metaHun was performed. Results were reported as standardized mean differences (SMD) and 95% confidence intervals graphically using forest and funnel plots.

RESULTS

Data from 9 trials with 426 patients living with T2DM were analyzed. Folic acid supplementation significantly revealed a large effect size on homocysteine levels compared to placebo, SMD = -1.53, 95%CI (-2.14,-0.93), p < 0.05. Additionally, we observed a medium marginal effect size on C-reactive protein (SMD = -0.68, 95%CI (-1.34, -0.01), p = 0.05). However, no significant effect on tumor necrosis factor-α (SMD = -0.86, 95%CI (-2.65, 0.93), p = 0.34), and interleukin-6 (SMD = -0.04, 95%CI (-1.08, 1.01), p = 0.95) was observed.

CONCLUSION

Evidence analyzed in this study suggests that folic acid supplementation in T2DM reduces homocysteine and may mitigate CVDs. However, its effect on inflammation is inconclusive.

The validity of electronic health data for measuring smoking status: a systematic review and meta-analysis

BACKGROUND

Smoking is a risk factor for many chronic diseases. Multiple smoking status ascertainment algorithms have been developed for population-based electronic health databases such as administrative databases and electronic medical records (EMRs). Evidence syntheses of algorithm validation studies have often focused on chronic diseases rather than risk factors. We conducted a systematic review and meta-analysis of smoking status ascertainment algorithms to describe the characteristics and validity of these algorithms.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. We searched articles published from 1990 to 2022 in EMBASE, MEDLINE, Scopus, and Web of Science with key terms such as validity, administrative data, electronic health records, smoking, and tobacco use. The extracted information, including article characteristics, algorithm characteristics, and validity measures, was descriptively analyzed. Sources of heterogeneity in validity measures were estimated using a meta-regression model. Risk of bias (ROB) in the reviewed articles was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

The initial search yielded 2086 articles; 57 were selected for review and 116 algorithms were identified. Almost three-quarters (71.6%) of algorithms were based on EMR data. The algorithms were primarily constructed using diagnosis codes for smoking-related conditions, although prescription medication codes for smoking treatments were also adopted. About half of the algorithms were developed using machine-learning models. The pooled estimates of positive predictive value, sensitivity, and specificity were 0.843, 0.672, and 0.918 respectively. Algorithm sensitivity and specificity were highly variable and ranged from 3 to 100% and 36 to 100%, respectively. Model-based algorithms had significantly greater sensitivity (p = 0.006) than rule-based algorithms. Algorithms for EMR data had higher sensitivity than algorithms for administrative data (p = 0.001). The ROB was low in most of the articles (76.3%) that underwent the assessment.

CONCLUSIONS

Multiple algorithms using different data sources and methods have been proposed to ascertain smoking status in electronic health data. Many algorithms had low sensitivity and positive predictive value, but the data source influenced their validity. Algorithms based on machine-learning models for multiple linked data sources have improved validity.

Effects of curcumin/turmeric supplementation on the liver enzymes, lipid profiles, glycemic index, and anthropometric indices in non-alcoholic fatty liver patients: An umbrella meta-analysis

Non-alcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease worldwide. The evidence for curcumin's effects on patients with NAFLD is accumulating; however, meta-analyses have reported mixed results. The current umbrella meta-analysis aimed to assess the present evidence and provide an accurate estimate of the overall effects of curcumin/turmeric on NAFLD patients. The Web of Science, Scopus, PubMed, ScienceDirect, and Google Scholar databases were searched till March 2023 using MeSH terms and related keywords based on the PICO criteria. Meta-analysis studies evaluating the effects of curcumin/turmeric supplementation on NAFLD patients that reported the effect sizes (ES) and corresponding confidence intervals (CI) were eligible for inclusion in this study. All articles were screened by considering the eligibility criteria by two independent reviewers and required data were extracted from the included meta-analyses. The meta-analysis was performed utilizing a random-effects model by STATA software. Findings of 11 meta-analyses of 99 randomized controlled trials comprising 5546 participants revealed that curcumin/turmeric supplementation reduced AST (ES = -1.072, 95% CI (-1.656, -0.488), p = 0.000), ALT (ES = -0.625, 95% CI (-1.170, -0.134), p = 0.014), and TG (ES = -0.469, 95% CI (-1.057, 0.119), p = 0.128) levels, and HOMA-IR (ES = -0.291, 95% CI (-0.368, -0.214), p = 0.000), BMI (ES = -0.205, 95% CI (-0.304, -0.107), p = 0.000), and WC (ES = -1.290, 95% CI (-2.038, -0.541), p = 0.001) in comparison to the control group. However, the effects of curcumin on GGT, ALP, TC, LDL-C, HDL-C, FBS, and HbA1C levels and body weight were not significant. The findings suggest the beneficial effects of curcumin/turmeric supplementation in patients with NAFLD, such as improving liver function, decreasing serum TG levels, ameliorating insulin resistance, and reducing general and central obesity. Nevertheless, high-quality research is further required to prove these achievements.

The Perils of Misinterpreting and Misusing "Publication Bias" in Meta-analyses: An Education Review on Funnel Plot-Based Methods

Publication bias refers to a systematic deviation from the truth in the results of a meta-analysis due to the higher likelihood for published studies to be included in meta-analyses than unpublished studies. Publication bias can lead to misleading recommendations for decision and policy making. In this education review, we introduce, explain, and provide solutions to the pervasive misuses and misinterpretations of publication bias that afflict evidence syntheses in sport and exercise medicine, with a focus on the commonly used funnel-plot based methods. Publication bias is more routinely assessed by visually inspecting funnel plot asymmetry, although it has been consistently deemed unreliable, leading to the development of statistical tests to assess publication bias. However, most statistical tests of publication bias (i) cannot rule out alternative explanations for funnel plot asymmetry (e.g., between-study heterogeneity, choice of metric, chance) and (ii) are grossly underpowered, even when using an arbitrary minimum threshold of ten or more studies. We performed a cross-sectional meta-research investigation of how publication bias was assessed in systematic reviews with meta-analyses published in the top two sport and exercise medicine journals throughout 2021. This analysis highlights that publication bias is frequently misused and misinterpreted, even in top tier journals. Because of conceptual and methodological problems when assessing and interpreting publication bias, preventive strategies (e.g., pre-registration, registered reports, disclosing protocol deviations, and reporting all study findings regardless of direction or magnitude) offer the best and most efficient solution to mitigate the misuse and misinterpretation of publication bias. Because true publication bias is very difficult to determine, we recommend that future publications use the term "risk of publication bias".

Association of carotid intima-media thickness and dyslipidaemia in patients with type 2 diabetes: a protocol for systematic review and meta-analysis

INTRODUCTION

Patients with diabetes mellitus (DM) often present with comorbidities such as hypertension, dyslipidaemia, insulin resistance, obesity and hyperglycaemia, which increases their risk of cardiovascular diseases (CVDs)-related mortality. Carotid intima-media thickness (CIMT), a biomarker for subclinical atherosclerosis, has been associated with overall CVD, especially in type 2 DM (T2DM). Hence, this protocol for systematic review and meta-analysis aims to review existing literature on the association of CIMT and dyslipidaemia in patients with T2DM.

METHODS AND ANALYSIS

The proposed systematic review and meta-analysis will be conducted according to an updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols guideline. A comprehensive search of peer-reviewed studies on Google Scholar, PubMed, Science Direct and Web of Sciences databases will be conducted up to 30 June 2023. A meta-analysis of data extracted from selected studies will be performed to explore the association between dyslipidaemia and CIMT in patients with diabetes. The effect estimates will be reported as standardised mean differences/Cohen's d and 95% CIs. A random effect model will be used in case of high heterogeneity whereas fixed-effect model will be used in the absence of heterogeneity. All statistical analysis will be performed using SPSS V.29.0 software. In cases of high heterogeneity, subgroup analysis will be performed based on study design, countries of publication and body mass index to identify potential sources of heterogeneity. Publication bias will be assessed graphically via funnel plots and statistically using Egger's regression test. Sensitivity analysis will also be performed to evaluate the stability of the overall effect size and the grading of recommendations assessment, development and evaluation will be used to grade the quality of analysed evidence.

ETHICS AND DISSEMINATION

As the proposed study will use secondary published data, approval will not be sought from the ethics committee.

PROSPERO REGISTRATION NUMBER

CRD42023451731.

The effect of smoking on response to methotrexate in rheumatoid arthritis patients: A systematic review and meta-analysis

OBJECTIVES

In the current study, we aimed to investigate the effect of smoking on inadequate response to methotrexate (MTX-IR) in rheumatoid arthritis (RA) patients.

METHODS

We searched PubMed, Embase, and Web of Science until 6 June 2022. Observational or interventional studies investigating MTX-IR in RA patients based on smoking status were included. Two independent reviewers assessed the risk of bias and the certainty of the evidence using the Risk of Bias in Nonrandomized Studies-of Interventions and Grades of Recommendation, Assessment, Development, and Evaluation tools, respectively.

RESULTS

We included 23 studies in the systematic review and 13 in the meta-analysis. Of the 13 included studies, 6 had a moderate risk, 3 had a serious risk, and 4 had a critical risk of bias. The overall random-effect meta-analysis suggested that smokers were 58% more likely to be MTX-IR when compared with nonsmokers [odds ratio (OR) 1.58, 95% confidence interval 1.21-2.06; P = .001; I2 = 69.3%]. The common-effect meta-analysis of the adjusted ORs demonstrated an overall OR of 2.69 (1.88-3.83; P < .001; I2 = 27.1%).

CONCLUSIONS

The current study showed that smoking is a significant predictor of MTX-IR, especially in disease-modifying antirheumatic drug-naïve early RA patients, as most of the included studies in the meta-analysis consisted of this population.

Effectiveness of Partial Body Weight-Supported Treadmill Training on Various Outcomes in Different Contexts among Children and Adolescents with Cerebral Palsy: A Systematic Review and Meta-Analysis

The efficiency of partial body weight-supported treadmill training (PBWSTT) for treating various conditions in children and adolescents with cerebral palsy (CP) in diverse contexts of rehabilitation, households, or schools is unknown. The major objective of this systematic review and meta-analysis was to analyze the effectiveness of PBWSTT on various outcomes in different contexts among children and adolescents with CP. We incorporated full-text, randomized controlled trial studies that specifically assessed the effects of PBWSTT walking, motor function, stride, balance, and endurance in children and adolescents aged 3 to 18 years with CP. The literature search was carried out using Google Scholar, PubMed, Web of Science, CINAHL Plus, Scopus, PEDro, and ResearchGate databases. The methodological quality was evaluated using a Cochrane risk of bias instrument. A meta-analysis of pooled data from 10 studies with 255 participants demonstrated that PBWSTT for 4-12 weeks in rehabilitation (mean difference [MD] = 1.94, 95% confidence interval [CI] = 1.40-2.48, p < 0.0001), at home or in a school context (MD = 13.5, 95% CI = 13.9-16.0, p < 0.0001), was significantly effective for treating various conditions in children and adolescents suffering with CP. The period of 4-12 weeks of PBWSTT in rehabilitation and at-home/school settings is effective on various outcomes in children or adolescents with CP.

Modulatory Properties of Vitamin D in Type 2 Diabetic Patients: A Focus on Inflammation and Dyslipidemia

BACKGROUND

Evidence from preclinical studies has found a correlation between the development of type 2 diabetes (T2D) and vitamin D deficiency. However, evidence from randomized controlled trials (RCTs) revealed inconclusive results on vitamin D supplementation. We explored the effect of vitamin D on inflammation and dyslipidemia in T2D.

METHODS

We comprehensively searched for RCTs evaluating the effect of vitamin D in T2D on PubMed. Data were analyzed using Review Manager 5.3 and reports, such as standardized mean difference (SMD) and 95% confidence intervals (CI) at a 5% significant level using a random effect model.

RESULTS

This study revealed a significant reduction in tumor necrosis factor-alpha (TNF-α) SMD = (-0.51, 95%CI (-0.93, -0.09); p = 0.02), high sensitivity C-reactive protein (hs-CRP) SMD = (-1.06, 95%CI (-1.67, -0.45); p < 0.05) in vitamin D compared to placebo. Additionally, interleukin-6 (IL-6) exhibited a marginal effect SMD = (-0.52, 95%CI (-1.05, 0.01), p = 0.05). Furthermore, a significant reduction in the level of triglycerides SMD = (-0.65, 95%CI (-1.11, -0.18), p < 0.05) was observed, concomitant to a significantly increased high-density lipoprotein (HDL) level SMD = (0.53, 95%CI (0.08, 0.98), p = 0.02). However, no statistically significant changes were observed in total cholesterols SMD = (-0.16, 95%CI (-0.57, 0.24), p = 0.43) and low-density lipoprotein (LDL) SMD = (-0.06, 95%CI (-0.37, 0.24), p = 0.67).

CONCLUSIONS

These findings suggest that vitamin D supplementation may be beneficial in ameliorating inflammation and dyslipidemia in T2D patients.

The Effect of Organic Trace Mineral Supplementation in the Form of Proteinates on Performance and Sustainability Parameters in Laying Hens: A Meta-Analysis

The effect of supplementing organic trace minerals (OTM), in the form of mineral proteinates (Bioplex® Cu, Fe, Mn, and Zn, Alltech Inc., Nicholasville, KY, USA), in the diets of laying hens was examined using Comprehensive Meta-Analysis (CMA) statistical software. The impact on production performance, egg quality traits, and sustainability parameters related to the carbon footprint of egg production was assessed. Data were obtained from 32 global studies, comprising 107 dietary assessments of 30,992 laying hens. Overall pooled effect size (raw mean difference) of production performance when dietary organic trace minerals were supplemented either in basal diets, partial replacement of inorganic trace minerals (ITM), or total replacement of ITM, indicated that use of Bioplex minerals resulted in 2.07% higher hen-day production (HDP), whilst feed conversion ratio (FCR) was lower by 51.28 g feed/kg egg and 22.82 g feed/dozen eggs, respectively. For egg quality traits, daily egg mass was 0.50 g/hen/day higher and egg weight was 0.48 g per egg greater when Bioplex minerals were incorporated in the diet. The mean difference in egg loss was -0.62%. Eggshell thickness was greater by 0.01 mm, and a higher eggshell strength of 0.14 kgf was observed. Eggshell weight was heavier by 0.20 g, eggshell percentage was higher by 0.15%, and Haugh unit was 1 point higher (0.89). We also carried out a meta-regression of the effects of the study factors (location, year of study, hen breed/strain, age of hens, number of hens, and study duration) on the overall pooled effect size of the production performance and egg quality traits in response to supplementary OTM inclusion, and it indicated that certain factors had a significant (p < 0.05) impact on the results. Finally, a life cycle assessment (LCA) model was selected to evaluate the impact of feeding organic trace mineral proteinates on the carbon footprint (feed and total emission intensities) of the egg production using the data generated from the meta-analysis. Results showed that the inclusion of OTM proteinates resulted in an average drop in feed and total emission intensities per kg eggs of 2.40% and 2.50%, respectively, for a low-global-warming-potential (GWP) diet and a drop of 2.40% and 2.48% for feed and total emissions, respectively, based on high-GWP diet. Based on the overall results, the inclusion of organic trace mineral proteinates in layer diets can benefit production performance and egg quality traits while contributing to a lower carbon footprint.

The Impact of Vitamin D Supplementation on Improving Blood Pressure: Evidence Obtained From an Umbrella Meta-analysis

PURPOSE

The results of meta-analyses regarding the effect of vitamin D on blood pressure are conflicting. The present umbrella meta-analysis was conducted to provide definite and conclusive results.

METHODS

Systematically, Scopus, EMBASE, PubMed, and Web of Science databases and Google Scholar were searched for relevant literature published up to July 2022. All meta-analyses of clinical trials addressing the effect of vitamin D on blood pressure were included. Random effects analysis was performed to obtain the overall effect size based on the standardized mean differences (SMDs) and weighted mean differences (WMDs) separately. The quality of included meta-analyses was assessed by using the Measurement Tool for Assessing Multiple Systematic Reviews 2 questionnaire.

FINDINGS

Overall, 21 meta-analyses were enrolled in the umbrella review. The results indicated that systolic blood pressure was significantly reduced after the intervention based on WMD effect size analysis (ESWMD = -0.69 mm Hg; 95% CI, -1.35 to -0.04 [P < 0.038]; I2 = 46.7%, P = 0.021); however, no considerable impact was observed based on analysis of SMD effect sizes (ESSMD = -0.05 mm Hg; 95% CI, -0.24 to 0.14; P = 0.615). Also, vitamin D supplementation indicated a significant improvement in diastolic blood pressure based on WMD effect sizes (ESWMD = -0.66 mm Hg; 95% CI, -1.05 to -0.27 [P < 0.001]; I2 = 56.4%, P = 0.004) but not SMD analysis (ESSMD = -0.04 mm Hg; 95% CI, -0.13 to 0.04 [P = 0.328]; I2 = 53.4%, P = 0.057).

IMPLICATIONS

Based on obtained evidence, vitamin D could be considered an efficient adjuvant for improving blood pressure.

A systematic review and meta-analysis of thigmotactic behaviour in the open field test in rodent models associated with persistent pain

Thigmotaxis is an innate predator avoidance behaviour of rodents. To gain insight into how injury and disease models, and analgesic drug treatments affect thigmotaxis, we performed a systematic review and meta-analysis of studies that assessed thigmotaxis in the open field test. Systematic searches were conducted of 3 databases in October 2020, March and August 2022. Study design characteristics and experimental data were extracted and analysed using a random-effects meta-analysis. We also assessed the correlation between thigmotaxis and stimulus-evoked limb withdrawal. This review included the meta-analysis of 165 studies We report thigmotaxis was increased in injury and disease models associated with persistent pain and this increase was attenuated by analgesic drug treatments in both rat and mouse experiments. Its usefulness, however, may be limited in certain injury and disease models because our analysis suggested that thigmotaxis may be associated with the locomotor function. We also conducted subgroup analyses and meta-regression, but our findings on sources of heterogeneity are inconclusive because analyses were limited by insufficient available data. It was difficult to assess internal validity because reporting of methodological quality measures was poor, therefore, the studies have an unclear risk of bias. The correlation between time in the centre (type of a thigmotactic metric) and types of stimulus-evoked limb withdrawal was inconsistent. Therefore, stimulus-evoked and ethologically relevant behavioural paradigms should be viewed as two separate entities as they are conceptually and methodologically different from each other.

The Role of Exercise in the Alleviation of Neuropathic Pain Following Traumatic Spinal Cord Injuries: A Systematic Review and Meta-analysis

OBJECTIVE

The objective of this systematic review and meta-analysis was to assess the efficacy of exercise in neuropathic pain following traumatic spinal cord injuries.

METHODS

The search was conducted in MEDLINE, Embase, Scopus, and Web of Science by the end of 2022. Two independent researchers included the articles based on the inclusion and exclusion criteria. A standardized mean difference was calculated for each data and they were pooled to calculate an overall effect size. To assess the heterogeneity between studies, I2 and chi-square tests were utilized. In the case of heterogeneity, meta-regression was performed to identify the potential source.

RESULTS

Fifteen preclinical studies were included. Meta-analysis demonstrated that exercise significantly improves mechanical allodynia (standardized mean difference [SMD], -1.59; 95% confidence interval [CI], -2.16 to -1.02; p < 0.001; I2 = 90.37%), thermal hyperalgesia (SMD, 1.95; 95% CI, 0.96-2.94; p < 0.001), and cold allodynia (SMD, -2.92; 95% CI, -4.4 to -1.43; p < 0.001). The improvement in mechanical allodynia is significantly more in animals with a compression model of SCI (meta-regression coefficient, -1.33; 95% CI, -1.84 to -0.57; p < 0.001) and in mild SCI (p < 0.001). Additionally, the improvement was more prominent if the training was started 7 to 8 days postinjury (coefficient, -2.54; 95% CI, -3.85 to -1.23; p < 0.001) and was continued every day (coefficient, -1.99; 95% CI, -3.07 to -0.9; p < 0.001). Likewise, voluntary exercise demonstrated a significantly more effect size (coefficient, -1.45; 95% CI, -2.67 to -0.23; p = 0.02).

CONCLUSION

Exercise is effective in the amelioration of neuropathic pain. This effect in mechanical allodynia is more prominent if voluntary, continuous training is initiated in the subacute phase of mild SCI.

Efficacy of antimalarial herbal medicines used by communities in malaria affected regions globally: a protocol for systematic review and evidence and gap map

INTRODUCTION

With the rising resistance to artemisinin-based combination treatments, there is a need to hasten the discovery and development of newer antimalarial agents. Herbal medicines are key for the development of novel drugs. Currently, herbal medicine usage in communities for treatment of malaria symptoms is common as an alternative to conventional (modern) antimalarial agents. However, the efficacy and safety of most of the herbal medicines has not yet been established. Therefore, this systematic review and evidence gap map (EGM) is intended to collate and map the available evidence, identify the gaps and synthesise the efficacy of herbal antimalarial medicines used in malaria affected regions globally.

METHODS AND ANALYSIS

The systematic review and EGM will be done following PRISMA and Campbell Collaboration guidelines respectively. This protocol has been registered in PROSPERO. Data sources will include PubMed, MEDLINE Ovid, EMBASE, Web of Science, Google Scholar and grey literature search. Data extraction will be done in duplicate using a data extraction tool tailored in Microsoft Office excel for herbal antimalarials discovery research questions following the PICOST framework. The Risk of Bias and overall quality of evidence will be assessed using Cochrane risk of bias tool (clinical trials), QUIN tool (in vitro studies), Newcastle-Ottawa tool (observational studies) and SYRCLE's risk of bias tool for animal studies (in vivo studies). Data analysis will be done using both structured narrative and quantitative synthesis. The primary review outcomes will be clinically important efficacy and adverse drug reactions. Laboratory parameters will include Inhibitory Concentration killing 50% of parasites, IC50; Ring Stage Assay, RSA0-3 hou; Trophozoite Survival Assay, TSA50. ETHICS AND DISSEMINATION: The review protocol was approved by the School of Biomedical Science Research Ethics Committee, Makerere University College of Health Sciences (SBS-2022-213).

PROSPERO REGISTRATION NUMBER

CRD42022367073.

Effectiveness of exercise programmes in improving physical function and reducing behavioural symptoms of community living older adults with dementia living in Asia, and impact on their informal carers: A systematic review and meta-analysis

Background

There is a growing evidence on the benefits of exercise for older people living with dementia in developed countries. However, cultural, health-care systems and environmental differences may impact on the uptake of exercise and outcomes in different regions of the world.

Objective

This study synthesised the available evidence examining the effectiveness of exercise interventions on improving physical function and reducing behavioural symptoms in community-dwelling older people living with dementia in Asia, and the impact on their informal carers.

Methods

Six databases were searched to November 2021. Randomised controlled trials (RCTs) or quasi-experimental studies evaluating exercise interventions for community-dwelling older people with dementia living in Asia were included. The Cochrane risk-of-bias tool for randomised trials and Downs and Black checklist had been used to assess methodological quality of the studies. Meta-analyses using a fixed effects model assessed the effects of exercise interventions where sufficient data were available. Mean difference (MD) with 95% confidence interval (CI) was used to pool results.

Results

Nine studies (five RCTs) were included (Hong Kong-4, China-1, South Korea-2, Taiwan-1, Indonesia-1). Exercise improved dynamic balance [Functional Reach (2 studies, n = 111 people with dementia), MD = 2 . 61 , 95% CI (1.55, 3.67)], but not for the Berg Balance Scale (MD = 1 . 10 , 95% CI [-2.88, 5.07]), Timed Up and Go (MD =- 3 . 47 , 95% CI [-7.27, 0.33]) and 5 times sit to stand tests (MD =- 1 . 86 , 95% CI [-5.27, 1.54]). Single studies where data could not be pooled showed no effect of exercise on behavioural symptoms or impact on informal carers.

Conclusion

Exercise appeared to have a beneficial effect on improving balance performance among older people with dementia living in Asia, however, this evidence is limited and inconsistent, and should be interpreted with caution. Further high-quality large RCTs are necessary for advancing the evidence base of exercise interventions for this population.

Non-opioid analgesics for the prevention of chronic postsurgical pain: a systematic review and network meta-analysis

BACKGROUND

Chronic postsurgical pain is common after surgery. Identification of non-opioid analgesics with potential for preventing chronic postsurgical pain is important, although trials are often underpowered. Network meta-analysis offers an opportunity to improve power and to identify the most promising therapy for clinical use and future studies.

METHODS

We conducted a PRISMA-NMA-compliant systematic review and network meta-analysis of randomised controlled trials of non-opioid analgesics for chronic postsurgical pain. Outcomes included incidence and severity of chronic postsurgical pain, serious adverse events, and chronic opioid use.

RESULTS

We included 132 randomised controlled trials with 23 902 participants. In order of efficacy, i.v. lidocaine (odds ratio [OR] 0.32; 95% credible interval [CrI] 0.17-0.58), ketamine (OR 0.64; 95% CrI 0.44-0.92), gabapentinoids (OR 0.67; 95% CrI 0.47-0.92), and possibly dexmedetomidine (OR 0.36; 95% CrI 0.12-1.00) reduced the incidence of chronic postsurgical pain at ≤6 months. There was little available evidence for chronic postsurgical pain at >6 months, combinations agents, chronic opioid use, and serious adverse events. Variable baseline risk was identified as a potential violation to the network meta-analysis transitivity assumption, so results are reported from a fixed value of this, with analgesics more effective at higher baseline risk. The confidence in these findings was low because of problems with risk of bias and imprecision.

CONCLUSIONS

Lidocaine (most effective), ketamine, and gabapentinoids could be effective in reducing chronic postsurgical pain ≤6 months although confidence is low. Moreover, variable baseline risk might violate transitivity in network meta-analysis of analgesics; this recommends use of our methods in future network meta-analyses.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO CRD42021269642.

Myocardial Tissue Characterization in Cardiac Magnetic Resonance Studies of Patients Recovering From COVID-19: A Meta-Analysis

Background Meta-analysis can identify biological factors that moderate cardiac magnetic resonance myocardial tissue markers such as native T1 (longitudinal magnetization relaxation time constant) and T2 (transverse magnetization relaxation time constant) in cohorts recovering from COVID-19 infection. Methods and Results Cardiac magnetic resonance studies of patients with COVID-19 using myocardial T1, T2 mapping, extracellular volume, and late gadolinium enhancement were identified by database searches. Pooled effect sizes and interstudy heterogeneity (I2) were estimated with random effects models. Moderators of interstudy heterogeneity were analyzed by meta-regression of the percent difference of native T1 and T2 between COVID-19 and control groups (%ΔT1 [percent difference of the study-level means of myocardial T1 in patients with COVID-19 and controls] and %ΔT2 [percent difference of the study-level means of myocardial T2 in patients with COVID-19 and controls]), extracellular volume, and the proportion of late gadolinium enhancement. Interstudy heterogeneities of %ΔT1 (I2=76%) and %ΔT2 (I2=88%) were significantly lower than for native T1 and T2, respectively, independent of field strength, with pooled effect sizes of %ΔT1=1.24% (95% CI, 0.54%-1.9%) and %ΔT2=3.77% (95% CI, 1.79%-5.79%). %ΔT1 was lower for studies in children (median age: 12.7 years) and athletes (median age: 21 years), compared with older adults (median age: 48 years). Duration of recovery from COVID-19, cardiac troponins, C-reactive protein, and age were significant moderators for %ΔT1 and/or %ΔT2. Extracellular volume, adjusted by age, was moderated by recovery duration. Age, diabetes, and hypertension were significant moderators of the proportion of late gadolinium enhancement in adults. Conclusions T1 and T2 are dynamic markers of cardiac involvement in COVID-19 that reflect the regression of cardiomyocyte injury and myocardial inflammation during recovery. Late gadolinium enhancement and to a lesser extent extracellular volume, are more static biomarkers moderated by preexisting risk factors linked to adverse myocardial tissue remodeling.

The performance of machine learning approaches for attenuation correction of PET in neuroimaging: A meta-analysis

PURPOSE

This systematic review provides a consensus on the clinical feasibility of machine learning (ML) methods for brain PET attenuation correction (AC). Performance of ML-AC were compared to clinical standards.

METHODS

Two hundred and eighty studies were identified through electronic searches of brain PET studies published between January 1, 2008, and August 1, 2022. Reported outcomes for image quality, tissue classification performance, regional and global bias were extracted to evaluate ML-AC performance. Methodological quality of included studies and the quality of evidence of analysed outcomes were assessed using QUADAS-2 and GRADE, respectively.

RESULTS

A total of 19 studies (2371 participants) met the inclusion criteria. Overall, the global bias of ML methods was 0.76 ± 1.2%. For image quality, the relative mean square error (RMSE) was 0.20 ± 0.4 while for tissues classification, the Dice similarity coefficient (DSC) for bone/soft tissue/air were 0.82 ± 0.1 / 0.95 ± 0.03 / 0.85 ± 0.14.

CONCLUSIONS

In general, ML-AC performance is within acceptable limits for clinical PET imaging. The sparse information on ML-AC robustness and its limited qualitative clinical evaluation may hinder clinical implementation in neuroimaging, especially for PET/MRI or emerging brain PET systems where standard AC approaches are not readily available.

A systematic evaluation of methodological and reporting quality of meta-analysis published in the field of gastrointestinal endoscopy

BACKGROUND

To evaluate the methodological and reporting quality of published meta-analyses (MAs) in four major gastrointestinal endoscopic journals, and identify the predicted factors for high quality.

METHODS

A systematic search was performed in PubMed to identify MAs from 1, January, 2016 to 31, December, 2020 in four major gastrointestinal endoscopic journals (including Digestive Endoscopy, Gastrointestinal Endoscopy, Surgical Endoscopy, and Endoscopy). We collected the characteristics of MAs after filtering unqualified articles, and assessed methodological and reporting qualities for eligible articles by AMSTAR tool and PRISMA checklist, respectively. Logistic regression was used for identifying predictive factors for high quality.

RESULTS

A total of 289 MAs were identified after screening by predefined inclusion and exclusion criteria. The scores (mean ± SD) of AMSTAR and PRISMA were 7.73 ± 1.11 and 22.90 ± 1.85, respectively. In PRISMA checklist, some items had less than 50% complete adherence, including item 2 (structured summary), items 5 (protocol and registration), items 12 and 19 (risk of bias in studies), item 27 (funding support). Item 1 (a priori design), item 4 (gray literature research), item 5 (list of included and excluded) were inferior to 50% adherence in AMSTAR tool. We found the predictive factors for high quality through logistic regression analysis: a priori design and funding support were associated with methodological quality. Protocol and registration influenced the methodological and reporting quality closely.

CONCLUSION

In general, qualities on the methodology and the reporting of MAs published in the gastrointestinal endoscopic journals are good, but both of which still potentially need further improvement.

Effects of probiotics supplementation on blood pressure: An umbrella meta-analysis of randomized controlled trials

AIMS

Several meta-analyses have revealed that probiotics could lower blood pressure (BP), but the findings were inconsistent. In this regard, an umbrella meta-analysis was carried out to provide a more accurate estimate of the overall impacts of probiotics supplementation on BP.

DATA SYNTHESIS

We searched the following international databases till November 2021: PubMed, Scopus, EMBASE, Web of Science, and Google Scholar. A random-effects model was applied to evaluate the effects of probiotics on BP. Sensitivity analysis was performed by using the leave-one-out method. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to evaluate the certainty of evidence. Pooled effect size of 14 meta-analyses with 15,494 participants indicated significant decreases in both systolic (Weighted mean difference (WMD) = -1.96 mmHg; 95% confidence interval (CI): -2.78, -1.14, p < 0.001, and standardized mean difference (SMD) = -2.62; 95% CI: -4.96, -0.28, p < 0.001) and diastolic BP (WMD = -1.28 mmHg; 95% CI: -1.76, -0.79, p < 0.001, and SMD = -0.60 mmHg; 95% CI: -1.08, -0.12, p = 0.014) following probiotics supplementation. Greater effects on SBP were revealed in trials with a mean age of >50 years and the duration of intervention ≤10 weeks. DBP was also more reduced in studies with a dosage of ≥10¹⁰ colony forming unit (CFU), and SBP was decreased in patients with hypertension or diabetes analyzing WMD.

CONCLUSION

The present umbrella meta-analysis suggests probiotics supplementation to improve BP and claims that probiotics could be used as a complementary therapy for controlling high BP.

PROSPERO ID

CRD42022306560.

Validity of using ambient concentrations as surrogate exposures at the individual level for fine particle and black carbon: A systematic review and meta-analysis

Exposure measurement error is an important source of bias in epidemiological studies. We assessed the validity of employing ambient (outdoor) measurements as proxies of personal exposures at individual levels focusing on fine particles (PM_2.5) and black carbon (BC)/elemental carbon (EC) on a global scale. We conducted a systematic review and meta-analysis and searched databases (ISI Web of Science, Scopus, PubMed, Ovid MEDLINE®, Ovid Embase, and Ovid BIOSIS) to retrieve observational studies in English language published from 1 January 2006 until 5 May 2021. Correlation coefficients (r) between paired ambient (outdoor) concentration and personal exposure for PM_2.5 or BC/EC were standardized as effect size. We used random-effects meta-analyses to pool the correlation coefficients and investigated the causes of heterogeneity and publication bias. Furthermore, we employed subgroup and meta-regression analyses to evaluate the modification of pooled estimates by potential mediators. This systematic review identified thirty-two observational studies involving 1744 subjects from ten countries, with 28 studies for PM_2.5 and 11 studies for BC/EC. Personal PM_2.5 exposure is more strongly correlated with ambient (outdoor) concentrations (0.63, 95% confidence interval [CI]: 0.57-0.68) than personal BC/EC exposure (0.49, 95% CI: 0.38-0.59), with significant differences in ṝ (0.14, 95% CI: 0.03-0.25; p < 0.05). The results demonstrated that the health status of participants was a significant modifier of pooled correlations. In addition, the personal to ambient (P/A) ratio for PM_2.5 and average ambient BC/EC levels were potential effect moderators of the pooled ṝ. The funnel plots and Egger's regression test indicated inevident publication bias. The pooled estimates were robust through sensitivity analyses. The results support the growing consensus that the validity coefficient of proxy measures should be addressed when interpreting results from epidemiological studies to better understand how strong health outcomes are affected by different levels of PM_2.5 and their components.

Complex agricultural landscapes host more biodiversity than simple ones: A global meta-analysis

Agricultural land, the world’s largest human-managed ecosystem, forms the matrix that connects remnant and fragmented patches of natural vegetation where nondomesticated biodiversity struggles to survive. Increasing the resources that this matrix can offer to biodiversity is critical to halting biodiversity loss. Our comprehensive meta-analysis demonstrates the positive and significant effect on biodiversity of increasing landscape complexity in agricultural lands. We found more biodiversity in complex landscapes, potentially contributing to agriculture production, ecosystem resilience, and human well-being. Current biodiversity conservation strategies tend to focus on natural ecosystems, often ignoring opportunities to boost biodiversity in agricultural landscapes. Our findings provide a strong scientific evidence base for synergistically managing agriculture at the landscape level for biodiversity conservation and sustainable production.

Managing agricultural landscapes to support biodiversity conservation requires profound structural changes worldwide. Often, discussions are centered on management at the field level. However, a wide and growing body of evidence calls for zooming out and targeting agricultural policies, research, and interventions at the landscape level to halt and reverse the decline in biodiversity, increase biodiversity-mediated ecosystem services in agricultural landscapes, and improve the resilience and adaptability of these ecosystems. We conducted the most comprehensive assessment to date on landscape complexity effects on nondomesticated terrestrial biodiversity through a meta-analysis of 1,134 effect sizes from 157 peer-reviewed articles. Increasing landscape complexity through changes in composition, configuration, or heterogeneity significatively and positively affects biodiversity. More complex landscapes host more biodiversity (richness, abundance, and evenness) with potential benefits to sustainable agricultural production and conservation, and effects are likely underestimated. The few articles that assessed the combined contribution of linear (e.g., hedgerows) and areal (e.g., woodlots) elements resulted in a near-doubling of the effect sizes (i.e., biodiversity level) compared to the dominant number of studies measuring these elements separately. Similarly, positive effects on biodiversity are stronger in articles monitoring biodiversity for at least 2 y compared to the dominant 1-y monitoring efforts. Besides, positive and stronger effects exist when monitoring occurs in nonoverlapping landscapes, highlighting the need for long-term and robustly designed monitoring efforts. Living in harmony with nature will require shifting paradigms toward valuing and promoting multifunctional agriculture at the farm and landscape levels with a research agenda that untangles complex agricultural landscapes’ contributions to people and nature under current and future conditions.

Comparative Analysis of Sedative Efficacy of Dexmedetomidine and Midazolam in Pediatric Dental Practice: A Systematic Review and Meta-Analysis

Children are particularly terrified of having dental treatment. They are physically resistant, frail, and unwilling to cooperate. This severe distress during the pre-operative phase could cause the dentist to have issues with behavior control. Additionally, it may make pediatric dental treatments less effective. In order to reduce anxiety and control behavior in children receiving dental care, sedation is a pharmacological management technique that supports the provision of effective and high-quality dental services. The aim is to compare and evaluate the efficacy of sedative agents like dexmedetomidine and midazolam in pediatric dental practice. A thorough review of the literature was conducted using electronic databases like "MEDLINE, PubMed, and CENTRAL (Cochrane Central Register of Controlled Trials), as well as the World Health Organization International Clinical Trials Registry Platform, www.clinicaltrials.gov, conference proceedings abstracts, a bibliography of pertinent references, and manual searches of journals, conferences, and books". There were no restrictions on the language or the date of publication when searching the electronic databases. Randomized controlled trials were included which compared dexmedetomidine and midazolam in children up to 16 years of age subjected to dental treatment. Information on procedures, participants, interventions, outcome measures, and results were independently extracted by three review writers (TS, SL, and RO). Trial authors were contacted for papers that were confusing or lacking information. The risk of bias was evaluated for each study. We adhered to the Cochrane statistical recommendations. Three trials totaling 229 participants were included. All three studies were rated as having a low risk of bias, with none of them having a high or unclear risk. Meta-analysis was done for the available data for the primary outcomes like sedation level and recovery time. We searched for randomized controlled trials up to Jan 31, 2020. Participants are randomly assigned to an intervention or control group in randomized controlled trial research. While patients in the control group often get a placebo therapy or procedure, those in the interventional group receive the treatment being studied. We found three studies eligible to include in the review. One study evaluated 73 individuals who received general anesthesia for dental treatment. There were 72 and 84 individuals in the second and third investigations, respectively. All the participants of the three studies were divided randomly into two groups and were subjected to dexmedetomidine and midazolam as sedative agents. We gave the evidence an "extremely low certainty" rating. Because there are just three short trials with unusual parameters for comparison, the results are questionable. Overall, the results do not allow us to draw any firm conclusions. Three randomized controlled trials included in this systematic review reported data with varying conclusions; hence we recommend more randomized controlled trials to be conducted on this subject matter.

Dressings and topical agents for the management of open wounds after surgical treatment for sacrococcygeal pilonidal sinus

BACKGROUND

Sacrococcygeal pilonidal sinus disease is a common debilitating condition that predominantly affects young adults, with a profound impact on their activities of daily living. The condition is treated surgically, and in some cases the wound in the natal cleft is left open to heal by itself. Many dressings and topical agents are available to aid healing of these wounds.

OBJECTIVES

To assess the effects of dressings and topical agents for the management of open wounds following surgical treatment for sacrococcygeal pilonidal sinus in any care setting.

SEARCH METHODS

In March 2021, we searched the Cochrane Wounds Specialised Register, CENTRAL, MEDLINE, Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and we scanned reference lists of included studies, reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

We included parallel-group randomised controlled trials (RCTs) only. We included studies with participants who had undergone any type of sacrococcygeal pilonidal sinus disease surgery and were left with an open wound.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We included 11 RCTs comprising 932 participants. Two studies compared topical negative pressure wound therapy (TNPWT) with conventional open wound healing, two studies compared platelet-rich plasma with sterile absorbent gauze, and the other seven studies compared various dressings and topical agents. All studies were at high risk of bias in at least one domain, whilst one study was judged to be at low risk of bias in all but one domain. All studies were conducted in secondary care. Mean participant ages were between 20 and 30 years, and nearly 80% of participants were male. No studies provided data on quality of life, cost-effectiveness, pain at first dressing change or proportion of wounds healed at 6 or 12 months, and very few adverse effects were recorded in any study. It is unclear whether TNPWT reduces time to wound healing compared with conventional open wound healing (comparison 1), as the certainty of evidence is very low. The two studies provided conflicting results, with one study showing benefit (mean difference (MD) -24.01 days, 95% confidence interval (CI) -35.65 to -12.37; 19 participants), whilst the other reported no difference. It is also unclear whether TNPWT has any effect on the proportion of wounds healed by 30 days (risk ratio (RR) 3.60, 95% CI 0.49 to 26.54; 19 participants, 1 study; very low-certainty evidence). Limited data were available for our secondary outcomes time to return to normal daily activities and recurrence rate; we do not know whether TNPWT has any effect on these outcomes. Lietofix cream may increase the proportion of wounds that heal by 30 days compared with an iodine dressing (comparison 4; RR 8.06, 95% CI 1.05 to 61.68; 205 participants, 1 study; low-certainty evidence). The study did not provide data on time to wound healing. We do not know whether hydrogel dressings reduce time to wound healing compared with wound cleaning with 10% povidone iodine (comparison 5; MD -24.54 days, 95% CI -47.72 to -1.36; 31 participants, 1 study; very low-certainty evidence). The study did not provide data on the proportion of wounds healed. It is unclear whether hydrogel dressings have any effect on adverse effects as the certainty of the evidence is very low. Platelet-rich plasma may reduce time to wound healing compared with sterile absorbent gauze (comparison 6; MD -19.63 days, 95% CI -34.69 to -4.57; 210 participants, 2 studies; low-certainty evidence). No studies provided data on the proportion of wounds healed. Platelet-rich plasma may reduce time to return to normal daily activities (MD -15.49, 95% CI -28.95 to -2.02; 210 participants, 2 studies; low-certainty evidence). Zinc oxide mesh may make little or no difference to time to wound healing compared with placebo (comparison 2; median 54 days in the zinc oxide mesh group versus 62 days in the placebo mesh group; low-certainty evidence). We do not know whether zinc oxide mesh has an effect on the proportion of wounds healed by 30 days as the certainty of the evidence is very low (RR 2.35, 95% CI 0.49 to 11.23). It is unclear whether gentamicin-impregnated collagen sponge reduces time to wound healing compared with no dressing (comparison 7; MD -1.40 days, 95% CI -5.05 to 2.25; 50 participants, 1 study; very low-certainty evidence). The study did not provide data on the proportion of wounds healed. Dialkylcarbamoyl chloride (DACC)-coated dressings may make little or no difference to time to wound healing compared with alginate dressings (comparison 8; median 69 (95% CI 62 to 72) days in the DACC group versus 71 (95% CI 69 to 85) days in the alginate group; 1 study, 246 participants; low-certainty evidence). One study compared a polyurethane foam hydrophilic dressing with an alginate dressing (comparison 3) whilst another study compared a hydrocolloid dressing with an iodine dressing (comparison 9). It is unclear whether either intervention has any effect on time to wound healing as the certainty of evidence is very low.

AUTHORS' CONCLUSIONS

At present, the evidence that any of the dressings or topical agents contained in this review have a benefit on time to wound healing, the proportion of wounds that heal at a specific time point or on any of the secondary outcomes of our review ranges from low certainty to very low certainty. There is low-certainty evidence on the benefit on wound healing of platelet-rich plasma from two studies and of Lietofix cream and hydrogel dressings from single studies. Further studies are required to investigate these interventions further.

The effect of non-oral hormonal contraceptives on hypertension and blood pressure: A systematic review and meta-analysis

Oral contraceptives (OC) are associated with increased risk of hypertension and elevated blood pressure (BP). Whether non-oral hormonal contraceptives have similar associations is unknown. We sought to investigate the effect of non-oral hormonal contraceptive (NOHC) use on the risk of hypertension and changes in BP, compared to non-hormonal contraceptive and OC use. We searched bibliographic databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials) until August 2020. Studies reporting risk of hypertension or changes in systolic and diastolic BP with NOHC use compared with either non-hormonal contraceptive or OC use. Abstract screening, full-text review, data extraction, and quality assessment were completed in duplicate. For studies reporting dichotomous outcomes, we reported results as relative risk with 95% confidence intervals (CI). A random-effects model was used to estimate pooled weighted mean difference and 95% CI of change in BP. Twenty-five studies were included. A lower incidence of hypertension was observed with injectable contraceptive use compared to non-hormonal contraceptive and OC use, although it was unclear if this was statistically significant. Compared to non-hormonal contraceptive use, injectable contraceptive use was associated with increased BP (SBP: 3.24 mmHg, 95%CI 2.49 to 3.98 mmHg; DBP: 3.15 mmHg, 95%CI 0.09 to 6.20 mmHg), the hormonal intra-uterine device use was associated with reduced BP (SBP: -4.50 mmHg, 95%CI -8.44 to -0.57 mmHg; DBP: -7.48 mmHg, 95% -14.90 to -0.05 mmHg), and the vaginal ring was associated with reduced diastolic BP (-3.90 mmHg, 95%CI -6.67 to -1.13 mmHg). Compared to OC use, the injectable contraceptive use was associated with increased diastolic BP (2.38 mmHg, 95%CI 0.39 to 4.38 mmHg). NOHC use is associated with changes in BP which differ by type and route of administration. Given the strong association between incremental increases in BP and cardiovascular risk, prospective studies are required.

The effect of animal versus plant protein on muscle mass, muscle strength, physical performance and sarcopenia in adults: protocol for a systematic review

BACKGROUND

The evidence base for the role of dietary protein in maintaining good muscle health in older age is strong; however, the importance of protein source remains unclear. Plant proteins are generally of lower quality, with a less favourable amino acid profile and reduced bioavailability; therefore, it is possible that their therapeutic effects may be less than that of higher quality animal proteins. This review aims to evaluate the effectiveness of plant and animal protein interventions on muscle health outcomes.

METHODS

A robust search strategy was developed to include terms relating to dietary protein with a focus on protein source, for example dairy, meat and soy. These were linked to terms related to muscle health outcomes, for example mass, strength, performance and sarcopenia. Five databases will be searched: MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, Embase and Web of Science. Studies included will be randomised controlled trials with an adult population (≥ 18) living in the community or residential homes for older adults, and only English language articles will be included. Two independent reviewers will assess eligibility of individual studies. The internal validity of included studies will be assessed using Cochrane Risk of Bias 2.0 tool. Results will be synthesised in narrative format. Where applicable, standardised mean differences (SMD) (95% confidence interval [CI]) will be combined using a random-effects meta-analysis, and tests of homogeneity of variance will be calculated.

DISCUSSION

Dietary guidelines recommend a change towards a plant-based diet that is more sustainable for health and for the environment; however, reduction of animal-based foods may impact protein quality in the diet. High-quality protein is important for maintenance of muscle health in older age; therefore, there is a need to understand whether replacement of animal protein with plant protein will make a significant difference in terms of muscle health outcomes. Findings from this review will be informative for sustainable nutritional guidelines, particularly for older adults and for those following vegan or vegetarian diets.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD420201886582.

The Cognitive Profile of Math Difficulties: A Meta-Analysis Based on Clinical Criteria

Math difficulties (MD) manifest across various domain-specific and domain-general abilities. However, the existing cognitive profile of MD is incomplete and thus not applicable in typical settings such as schools or clinics. So far, no review has applied inclusion criteria according to DSM or ICD, summarized domain-specific abilities or examined the validity of response time scores for MD identification. Based upon stringent clinical criteria, the current meta-analysis included 34 studies which compared cognitive performances of a group with MD (n = 680) and a group without MD (n = 1565). Criteria according to DSM and ICD were applied to identify MD (percentile rank ≤ 16, age range 8-12 years, no comorbidities/low IQ). Effect sizes for 22 abilities were estimated and separated by their level and type of scoring (AC = accuracy, RT = response time). A cognitive profile of MD was identified, characterized by distinct weaknesses in: (a) computation (calculation [AC], fact retrieval [AC]), (b) number sense (quantity processing [AC], quantity-number linking [RT], numerical relations [AC]), and (c) visual-spatial short-term storage [AC]. No particular strength was found. Severity of MD, group differences in reading performance and IQ did not significantly moderate the results. Further analyses revealed that (a) effects are larger when dealing with numbers or number words than with quantities, (b) MD is not accompanied by any weakness in abilities typically assigned to reading, and (c) weaknesses in visual-spatial short-term storage emphasize the notion that number and space are interlinked. The need for high-quality studies investigating domain-general abilities is discussed.

SARS-CoV-2 infection during pregnancy and risk of preeclampsia: a systematic review and meta-analysis

OBJECTIVE

To examine the relationship between SARS-CoV-2 infection during pregnancy and the risk for preeclampsia.

DATA SOURCES

MEDLINE, Embase, POPLINE, CINAHL, LILACS, and the World Health Organization COVID-19, Chinese, and preprint databases (all from December 1, 2019, to May 31, 2021). Google Scholar, bibliographies, and conference proceedings were also searched.

STUDY ELIGIBILITY CRITERIA

Observational studies that assessed the association between SARS-CoV-2 infection during pregnancy and preeclampsia and that reported unadjusted and/or adjusted risk estimates and 95% confidence intervals or data to calculate them.

STUDY APPRAISAL AND SYNTHESIS METHODS

The primary outcome was preeclampsia. Secondary outcomes included preeclampsia with severe features, preeclampsia without severe features, eclampsia, and hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome. Two reviewers independently reviewed studies for inclusion, assessed their risk of bias, and extracted data. Pooled unadjusted and adjusted odds ratios with 95% confidence intervals, and 95% prediction interval were calculated. Heterogeneity was quantified using the І2 statistic, for which І2≥30% indicated substantial heterogeneity. Subgroup and sensitivity analyses were performed to test the robustness of the overall findings.

RESULTS

A total of 28 studies comprising 790,954 pregnant women, among which 15,524 were diagnosed with SARS-CoV-2 infection, met the inclusion criteria. The meta-analysis of unadjusted odds ratios showed that the odds of developing preeclampsia were significantly higher among pregnant women with SARS-CoV-2 infection than among those without SARS-CoV-2 infection (7.0% vs 4.8%; pooled odds ratio, 1.62; 95% confidence interval, 1.45-1.82; P<.00001; І2=17%; 26 studies; 95% prediction interval of the odds ratio, 1.28-2.05). The meta-analysis of adjusted odds ratios also showed that SARS-CoV-2 infection during pregnancy was associated with a significant increase in the odds of preeclampsia (pooled odds ratio, 1.58; 95% confidence interval, 1.39-1.80; P<.0001; І2=0%; 11 studies). There was a statistically significant increase in the odds of preeclampsia with severe features (odds ratio, 1.76; 95% confidence interval, 1.18-2.63; І2=58%; 7 studies), eclampsia (odds ratio, 1.97; 95% confidence interval, 1.01-3.84; І2=0%, 3 studies), and HELLP syndrome (odds ratio, 2.10; 95% confidence interval, 1.48-2.97; 1 study) among pregnant women with SARS-CoV-2 infection when compared to those without the infection. Overall, the direction and magnitude of the effect of SARS-CoV-2 infection during pregnancy on preeclampsia was consistent across most prespecified subgroup and sensitivity analyses. Both asymptomatic and symptomatic SARS-CoV-2 infections significantly increased the odds of developing preeclampsial; however, it was higher among patients with symptomatic illness (odds ratio, 2.11; 95% confidence interval, 1.59-2.81) than among those with asymptomatic illness (odds ratio, 1.59; 95% confidence interval, 1.21-2.10).

CONCLUSION

SARS-CoV-2 during pregnancy is associated with higher odds of preeclampsia.

The effects of radiofrequency exposure on male fertility and adverse reproductive outcomes: A protocol for two systematic reviews of human observational studies with meta-analysis

BACKGROUND

The World Health Organization (WHO) is bringing together evidence on radiofrequency electromagnetic field (RF-EMF) exposure in relation to health outcomes, previously identified as priorities for evaluation by experts in the field, to inform exposure guidelines. A suite of systematic reviews are being undertaken by a network of topic experts and methodologists in order to collect, assess and synthesise data relevant to these guidelines. Here, we present the protocol for the systematic review on the effect of exposure to RF on adverse reproductive outcomes (human observational studies), also referred to as Systematic Review (SR) 3 within the series of systematic reviews currently being commissioned.

OBJECTIVES

Following the WHO handbook for guideline development and the COSTER conduct guidelines, we will systematically review the effect of RF-EMF exposure on both male fertility (SR3A) and adverse pregnancy outcomes (SR3B) in human observational studies. Herein we adhere to the PRISMA-P reporting guidelines.

DATA SOURCES

We will conduct a broad search for potentially relevant records relevant for both reviews within the following bibliographic databases: MEDLINE; Embase; and EMF Portal. We will also conduct searches of grey literature through relevant databases and organisational websites. RF-EMF experts will also be consulted. We will hand search citation and reference lists of included study records.

STUDY ELIGIBILITY CRITERIA

We will include quantitative human observational studies on the effect of RF-EMF exposure: (in SR3A) in adult male participants on infertility, sperm morphology, concentration or total sperm count or motility; and (in SR3B) in preconception adults or pregnant women on preterm birth, small for gestational age (associated with intrauterine growth restriction), miscarriage, stillbirth and congenital anomalies.

STUDY APPRAISAL AND SYNTHESIS METHODS

Titles, abstracts and then full texts will be screened in blinded duplicate against eligibility criteria with input from a third reviewer as required. Data extraction from included studies will be completed by two reviewers as will risk of bias assessment using the Office of Health Assessment and Translation (OHAT) tool. If appropriate we will undertake meta-analysis to pool effect measures and explore heterogeneity using sub-group analyses or meta-regression as feasible. We will conduct sensitivity analysis to assess the impact of any assumptions made throughout the review process. The OHAT methodology, based on the GRADE guidelines for evidence assessment, will be used to evaluate the certainty of evidence per outcome and to conclude the level of evidence of a health effect.

CONCLUSION

This manuscript details the protocols for two systematic reviews. The aims of publishing details of both protocols are to: pre-specify their scope and methods; reduce the impact of reviewer bias; promote transparency and replicability; and improve the review process.

PROSPERO REGISTRATION

CRD42021265401 (SR3A), CRD42021266268 (SR3B).

Abdominal drainage to prevent intra-peritoneal abscess after appendectomy for complicated appendicitis

BACKGROUND

This is the second update of a Cochrane Review first published in 2015 and last updated in 2018. Appendectomy, the surgical removal of the appendix, is performed primarily for acute appendicitis. Patients who undergo appendectomy for complicated appendicitis, defined as gangrenous or perforated appendicitis, are more likely to suffer postoperative complications. The routine use of abdominal drainage to reduce postoperative complications after appendectomy for complicated appendicitis is controversial.

OBJECTIVES

To assess the safety and efficacy of abdominal drainage to prevent intraperitoneal abscess after appendectomy (irrespective of open or laparoscopic) for complicated appendicitis; to compare the effects of different types of surgical drains; and to evaluate the optimal time for drain removal.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid Embase, Web of Science, the World Health Organization International Trials Registry Platform, ClinicalTrials.gov, Chinese Biomedical Literature Database, and three trials registers on 24 February 2020, together with reference checking, citation searching, and contact with study authors to identify additional studies.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that compared abdominal drainage versus no drainage in people undergoing emergency open or laparoscopic appendectomy for complicated appendicitis. We also included RCTs that compared different types of drains and different schedules for drain removal in people undergoing appendectomy for complicated appendicitis.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently identified the trials for inclusion, collected the data, and assessed the risk of bias. We used the GRADE approach to assess evidence certainty. We included intraperitoneal abscess as the primary outcome. Secondary outcomes were wound infection, morbidity, mortality, hospital stay, hospital costs, pain, and quality of life.

MAIN RESULTS

Use of drain versus no drain We included six RCTs (521 participants) comparing abdominal drainage and no drainage in participants undergoing emergency open appendectomy for complicated appendicitis. The studies were conducted in North America, Asia, and Africa. The majority of participants had perforated appendicitis with local or general peritonitis. All participants received antibiotic regimens after open appendectomy. None of the trials was assessed as at low risk of bias. The evidence is very uncertain regarding the effects of abdominal drainage versus no drainage on intraperitoneal abscess at 30 days (risk ratio (RR) 1.23, 95% confidence interval (CI) 0.47 to 3.21; 5 RCTs; 453 participants; very low-certainty evidence) or wound infection at 30 days (RR 2.01, 95% CI 0.88 to 4.56; 5 RCTs; 478 participants; very low-certainty evidence). There were seven deaths in the drainage group (N = 183) compared to one in the no-drainage group (N = 180), equating to an increase in the risk of 30-day mortality from 0.6% to 2.7% (Peto odds ratio 4.88, 95% CI 1.18 to 20.09; 4 RCTs; 363 participants; low-certainty evidence). Abdominal drainage may increase 30-day overall complication rate (morbidity; RR 6.67, 95% CI 2.13 to 20.87; 1 RCT; 90 participants; low-certainty evidence) and hospital stay by 2.17 days (95% CI 1.76 to 2.58; 3 RCTs; 298 participants; low-certainty evidence) compared to no drainage. The outcomes hospital costs, pain, and quality of life were not reported in any of the included studies. There were no RCTs comparing the use of drain versus no drain in participants undergoing emergency laparoscopic appendectomy for complicated appendicitis. Open drain versus closed drain There were no RCTs comparing open drain versus closed drain for complicated appendicitis. Early versus late drain removal There were no RCTs comparing early versus late drain removal for complicated appendicitis.

AUTHORS' CONCLUSIONS

The certainty of the currently available evidence is low to very low. The effect of abdominal drainage on the prevention of intraperitoneal abscess or wound infection after open appendectomy is uncertain for patients with complicated appendicitis. The increased rates for overall complication rate and hospital stay for the drainage group compared to the no-drainage group are based on low-certainty evidence. Consequently, there is no evidence for any clinical improvement with the use of abdominal drainage in patients undergoing open appendectomy for complicated appendicitis. The increased risk of mortality with drainage comes from eight deaths observed in just under 400 recruited participants. Larger studies are needed to more reliably determine the effects of drainage on morbidity and mortality outcomes.

Pre-emptive and preventive NSAIDs for postoperative pain in adults undergoing all types of surgery

BACKGROUND

Postoperative pain is a common consequence of surgery and can have many negative perioperative effects. It has been suggested that the administration of analgesia before a painful stimulus may improve pain control. We defined pre-emptive nonsteroidal anti-inflammatories (NSAIDs) as those given before surgery but not continued afterwards and preventive NSAIDs as those given before surgery and continued afterwards. These were compared to a control group given the NSAIDs after surgery instead of before surgery.

OBJECTIVES

To assess the efficacy of preventive and pre-emptive NSAIDs for reducing postoperative pain in adults undergoing all types of surgery.

SEARCH METHODS

We searched the following electronic databases: CENTRAL, MEDLINE, Embase, AMED and CINAHL (up to June 2020). In addition, we searched for unpublished studies in three clinical trial databases, conference proceedings, grey literature databases, and reference lists of retrieved articles. We did not apply any restrictions on language or date of publication.

SELECTION CRITERIA

We included parallel-group randomized controlled trials (RCTs) only. We included adult participants undergoing any type of surgery. We defined pre-emptive NSAIDs as those given before surgery but not continued afterwards and preventive NSAIDs as those given before surgery and continued afterwards. These were compared to a control group given the NSAIDs after surgery instead of before surgery. We included studies that gave the medication by any route but not given on the skin.

DATA COLLECTION AND ANALYSIS

We used the standard methods expected by Cochrane, as well as a novel publication bias test developed by our research group. We used GRADE to assess the certainty of the evidence for each outcome. Outcomes included acute postoperative pain (minimal clinically important difference (MCID): 1.5 on a 0-10 scale), adverse events of NSAIDs, nausea and vomiting, 24-hour morphine consumption (MCID: 10 mg reduction), time to analgesic request (MCID: one hour), pruritus, sedation, patient satisfaction, chronic pain and time to first bowel movement (MCID: 12 hours).

MAIN RESULTS

We included 71 RCTs. Seven studies are awaiting classification. We included 45 studies that evaluated pre-emptive NSAIDs and 26 studies that evaluated preventive NSAIDs. We considered only four studies to be at low risk of bias for most domains. The operations and NSAIDs used varied, although most studies were conducted in abdominal, orthopaedic and dental surgery. Most studies were conducted in secondary care and in low-risk participants. Common exclusions were participants on analgesic medications prior to surgery and those with chronic pain. Pre-emptive NSAIDs compared to post-incision NSAIDs For pre-emptive NSAIDs, there is probably a decrease in early acute postoperative pain (MD -0.69, 95% CI -0.97 to -0.41; studies = 36; participants = 2032; I2 = 96%; moderate-certainty evidence). None of the included studies that reported on acute postoperative pain reported adverse events as an outcome. There may be little or no difference between the groups in short-term (RR 1.00, 95% CI 0.34 to 2.94; studies = 2; participants = 100; I2 = 0%; low-certainty evidence) or long-term nausea and vomiting (RR 0.85, 95% CI 0.52 to 1.38; studies = 5; participants = 228; I2 = 29%; low-certainty evidence). There may be a reduction in late acute postoperative pain (MD -0.22, 95% CI -0.44 to 0.00; studies = 28; participants = 1645; I2 = 97%; low-certainty evidence). There may be a reduction in 24-hour morphine consumption with pre-emptive NSAIDs (MD -5.62 mg, 95% CI -9.00 mg to -2.24 mg; studies = 16; participants = 854; I2 = 99%; low-certainty evidence) and an increase in the time to analgesic request (MD 17.04 minutes, 95% CI 3.77 minutes to 30.31 minutes; studies = 18; participants = 975; I2 = 95%; low-certainty evidence). There may be little or no difference in opioid adverse events such as pruritus (RR 0.40, 95% CI 0.09 to 1.76; studies = 4; participants = 254; I2 = 0%; low-certainty evidence) or sedation (RR 0.51, 95% CI 0.16 to 1.68; studies = 4; participants = 281; I2 = 0%; low-certainty evidence), although the number of included studies for these outcomes was small. No study reported patient satisfaction, chronic pain or time to first bowel movement for pre-emptive NSAIDs. Preventive NSAIDs compared to post-incision NSAIDs For preventive NSAIDs, there may be little or no difference in early acute postoperative pain (MD -0.14, 95% CI -0.39 to 0.12; studies = 18; participants = 1140; I2 = 75%; low-certainty evidence). One study reported adverse events from NSAIDs (reoperation for bleeding) although the events were low which did not allow any meaningful conclusions to be drawn (RR 1.95; 95% CI 0.18 to 20.68). There may be little or no difference in rates of short-term (RR 1.26, 95% CI 0.49 to 3.30; studies = 1; participants = 76; low-certainty evidence) or long-term (RR 0.85, 95% CI 0.52 to 1.38; studies = 5; participants = 456; I2 = 29%; low-certainty evidence) nausea and vomiting. There may be a reduction in late acute postoperative pain (MD -0.33, 95% CI -0.59 to -0.07; studies = 21; participants = 1441; I2 = 81%; low-certainty evidence). There is probably a reduction in 24-hour morphine consumption (MD -1.93 mg, 95% CI -3.55 mg to -0.32 mg; studies = 16; participants = 1323; I2 = 49%; moderate-certainty evidence). It is uncertain if there is any difference in time to analgesic request (MD 8.51 minutes, 95% CI -31.24 minutes to 48.27 minutes; studies = 8; participants = 410; I2 = 98%; very low-certainty evidence). As with pre-emptive NSAIDs, there may be little or no difference in other opioid adverse events such as pruritus (RR 0.56, 95% CI 0.09 to 3.35; studies = 3; participants = 211; I2 = 0%; low-certainty evidence) and sedation (RR 0.84, 95% CI 0.44 to 1.63; studies = 5; participants = 497; I2 = 0%; low-certainty evidence). There is probably little or no difference in patient satisfaction (MD -0.42; 95% CI -1.09 to 0.25; studies = 1; participants = 72; moderate-certainty evidence). No study reported on chronic pain. There is probably little or no difference in time to first bowel movement (MD 0.00; 95% CI -15.99 to 15.99; studies = 1; participants = 76; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

There was some evidence that pre-emptive and preventive NSAIDs reduce both pain and morphine consumption, although this was not universal for all pain and morphine consumption outcomes. Any differences found were not clinically significant, although we cannot exclude this in more painful operations. Moreover, without any evidence of reductions in opioid adverse effects, the clinical significance of these results is questionable although few studies reported these outcomes. Only one study reported clinically significant adverse events from NSAIDs administered before surgery and, therefore, we have very few data to assess the safety of either pre-emptive or preventive NSAIDs. Therefore, future research should aim to adhere to the highest methodology and be adequately powered to assess serious adverse events of NSAIDs and reductions in opioid adverse events.

Methodologies for systematic reviews with meta-analysis of randomised clinical trials in pain, anaesthesia, and perioperative medicine

Systematic reviews and meta-analyses (SRMAs) are increasing in popularity, but should they be used to inform clinical decision-making in anaesthesia? We present evidence that the certainty of evidence from SRMAs in anaesthesia (and in general) may be unacceptably low because of risks of bias exaggerating treatment effects, unexplained heterogeneity reducing certainty in estimates, random errors, and widespread prevalence of publication bias. We also present the latest methodological advances to help improve the certainty of evidence from SRMAs. The target audience includes both review authors and practising clinicians to help with SRMA appraisal. Issues discussed include minimising risks of bias from included trials, trial sequential analysis to reduce random error, updated methods for presenting effect estimates, and novel publication bias tests for commonly used outcome measures. These methods can help to reduce spurious conclusions on clinical significance, explain statistical heterogeneity, and reduce false positives when evaluating small-study effects. By reducing concerns in these domains of Grading of Recommendations, Assessment, Development and Evaluation, it should help improve the certainty of evidence from SRMAs used for decision-making in anaesthesia, pain, and perioperative medicine.