Inverse Variance Heterogeneity Model Research Articles

No Difference in Overall Survival and Non-Breast Cancer Deaths after Partial Breast Radiotherapy Compared to Whole Breast Radiotherapy-A Meta-Analysis of Randomized Trials.

Purpose/objective: Adjuvant radiotherapy after breast conserving surgery is the standard approach in early stage breast cancer. However, the extent of breast tissue that has to be targeted with radiation has not been determined yet. Traditionally, the whole breast was covered by two opposing tangential beams. Several randomized trials have tested partial breast irradiation (PBI) compared to whole breast irradiation (WBI) using different radiation techniques. There is evidence from randomized trials that PBI might result in lower mortality rates compared to WBI. We aimed to reassess this question using current data from randomized trials. Material/methods: We performed a systematic literature review searching for randomized trials comparing WBI and PBI in early stage breast cancer with publication dates after 2009. The meta-analysis was performed using the published event rates and the effect sizes for overall survival (OS), breast cancer-specific survival (BCSS), and non-breast cancer death (NBCD) as investigated endpoints. Analysis of subgroups using different radiation techniques was intended. We used hazard ratios (HR) and risk differences (RD) to estimate pooled effect sizes. Statistical analysis was performed using the inverse variance heterogeneity model. Results: We identified eleven studies randomizing between PBI and WBI. We did not find significant differences in OS (n = 14,070; HR = 1.02; CI-95%: 0.89–1.16; p = 0.810, and n = 15,203; RD = −0.001; CI-95%: −0.008–0.006; p = 0.785) and BCSS (n = 15,203; RD = 0.001; CI-95%: −0.002–0.005; p = 0.463). PBI also did not result in a significant decrease of NBCD (n = 15,203; RD = −0.003; CI-95%: −0.010–0.003; p = 0.349). A subgroup analysis by radiation technique also did not point to any detectable differences. Conclusion: In contrast to a previous assessment of mortality, we could not find a detrimental effect of WBI on OS or NBCD. A longer follow-up might be necessary to fully assess the long-term mortality effects of PBI compared to WBI.

Inter-individual differences in body mass index were not observed as a result of aerobic exercise in children and adolescents with overweight and obesity.

Exercise has been recommended as an important intervention for reducing adiposity in children and adolescents with overweight and obesity. Determine whether inter-individual differences exist in relation to exercise-induced changes in adiposity among children and adolescents with overweight and obesity. Meta-analysis of randomized controlled aerobic exercise trials and body mass index (BMI) in kg · m-2 . Change outcome standard deviations were pooled using the inverse-variance heterogeneity model. Twenty-eight studies (1185 participants) were included. Inter-individual differences in BMI were -0.1 (95% compatibility interval, -0.7 to 0.7). The 95% prediction interval for inter-individual responses in a future study was -2.9 to 2.9. The probability of a clinically meaningful difference in variability was 29% (possibly clinically important) in favour of controls vs exercisers. Inter-individual differences for BMI in kg · m-2 were not observed as a result of aerobic exercise in children and adolescents with overweight and obesity.

Are There Inter-Individual Differences in Fat Mass and Percent Body Fat as a Result of Aerobic Exercise Training in Overweight and Obese Children and Adolescents? A Meta-Analytic Perspective.

Background: Determine whether inter-individual response differences exist with respect to changes in fat mass and percent body fat as a result of aerobic exercise training in overweight and obese children and adolescents. Methods: Using the meta-analytic approach, randomized controlled trials that examined the effects of aerobic exercise training on fat mass and percent body fat in overweight and obese children and adolescents were included. Change outcome standard deviations for fat mass and percent body fat were used to calculate true inter-individual differences from each study. The inverse variance heterogeneity model was used to pool results. Results: Pooled changes for inter-individual response differences in fat mass (16 studies, 575 participants) were 0.9 kg (95% confidence interval [CI], -1.4 to 1.8 kg) while tau ([Formula: see text]) was 2.9. For percent body fat, inter-individual differences (27 studies, 1035 participants) were 0.6% (95% CI, -0.6% to 1.0%, [Formula: see text] = 0.7). The 95% prediction interval for true inter-individual responses in a future study was -4.9 to 5.5 kg for fat mass and -0.7% to 1.7% for percent body fat. The percent chance, that is, probability, of a clinically meaningful difference in variability was 47% for fat mass and 26% for percent body fat, both of which were considered as only possibly clinically important. Conclusions: There is a lack of convincing evidence to suggest that true inter-individual response differences exist with respect to aerobic exercise training and changes in fat mass and percent body fat in overweight and obese children and adolescents.

Comparison of different systemic therapeutic regimes in resectable high-risk soft tissue sarcoma: Results of a network meta-analysis.

11549 Background: The treatment of high-risk soft tissue sarcoma of the trunk or the extremities consists of surgical resection with risk-adapted radiation therapy. Further treatment options which can significantly improve local and systemic tumor control including chemotherapy are not well established. Due to the heterogeneity of disease different systemic approaches as well as their application during different time points have been attempted. Methods: We conducted a literature search for randomized clinical trials in the treatment of localized, resectable high-risk soft tissue sarcoma comparing different treatment modalities according to the PRISMA guidelines. We extracted published hazard ratios and number of events for the endpoints of overall and disease-free survival (OS; DFS) as well as local and distant recurrence-free interval (LRFI; DRFI). The different modalities were compared in a network meta-analysis against the defined standard treatment surgery ± radiotherapy using the inverse-variance heterogeneity model (ivhet) with the help of the Microsoft Excel add-in Meta-XL V5.3. Results: The literature search identified 25 studies including 3489 patients. The network analysis showed that adjuvant chemotherapy (adjCTx) results in a significant improvement in overall survival (HR = 0.86; CI-95%: 0.75-0.97; p = 0.017) compared to the standard treatment of surgery ± radiatherapy alone. Combined treatment with regional hyperthermia and neoadjuvant chemotherapy (HTx+nadjCTx) also improves OS (HR = 0.45; CI-95%: 0.20-1.00; p = 0.049). Preoperative chemotherapy alone (nadjCTx) as well as perioperative chemotherapy (periopCTx) resulted both in non-statistically significant improvements in OS (HR = 0.61; CI-95%: 0.29-1.29; p = 0.195) and (HR = 0.48; CI-95%: 0.15-1.55; p = 0.218). Histology-tailored neoadjuvant chemotherapy (tNaCTx) also showed no effect on overall survival (HR = 1.08; CI-95%: 0.45-2.61; p = 0.868). The analysis of DFS, LRFI and DRFI disclosed a similar pattern between the different treatment regimens. Conclusions: The addition of cytotoxic chemotherapy in resectable high-risk soft tissue sarcomas provides a measurable benefit in overall survival. Shifting of systemic therapy to the neoadjuvant setting and combination with regional hyperthermia might be favored. Predictive clinical and molecular markers are needed to evaluate and limit potentional risks prospectively going forward.

Selecting the best meta-analytic estimator for evidence-based practice: a simulation study.

Studies included in meta-analysis can produce results that depart from the true population parameter of interest due to systematic and/or random errors. Synthesis of these results in meta-analysis aims to generate an estimate closer to the true population parameter by minimizing these errors across studies. The inverse variance heterogeneity (IVhet), quality effects and random effects models of meta-analysis all attempt to do this, but there remains controversy around the estimator that best achieves this goal of reducing error. In an attempt to answer this question, a simulation study was conducted to compare estimator performance. Five thousand iterations at 10 different levels of heterogeneity were run, with each iteration generating one meta-analysis. The results demonstrate that the IVhet and quality effects estimators, though biased, have the lowest mean squared error. These estimators also achieved a coverage probability at or above the nominal level (95%), whereas the coverage probability under the random effects estimator significantly declined (<80%) as heterogeneity increased despite a similar confidence interval width. Based on our findings, we would recommend the use of the IVhet and quality effects models and a discontinuation of traditional random effects models currently in use for meta-analysis.

Patient preference and operating time for digital versus conventional impressions: a network meta-analysis.

Digital impression techniques haveseen many advancements, with new hardware and software being developed each year. The technical advantages of these systems are real-time visualization, evaluation and archive, segmental capture, ease of recapture if necessary, economical in terms of no use of impression material or trays or disinfection, easy file transfer and communication with the laboratory. However patient satisfaction is one major factor that might influence the choice of impression technique. The aim of this network meta-analysis was to identify statistically the evidence on overall patient preferences relative to digital versus conventional impression techniques, in addition to the time taken in making these impressions. Randomized or prospective clinical studies were identified based on the inclusion criteria in PUBMED, DARE and COCHRANE databases; subsequently pertinent data were extracted. Risk of bias of the included studies was assessed using the Cochrane risk of bias tool and Newcastle-Ottawa scale. Heterogeneity amongst the studies in direct comparison was assessed by Chi-square and I2 tests using the Inverse variance heterogeneity model. Direct comparison estimates were derived by pooling the data from studies that compared the same intervention. Indirect comparison pooled estimates were derived by using the data amongst the studies, through a common comparator, using MetaXL software. Mean differences and Odds ratio at 95% confidence interval were used as the effect estimates, while inconsistencies were evaluated by H-statistics. GRADE working group approach was used to assess the quality of available evidence. Fourteen studies were included. Results from 11 studies on 471 patients (236-Digital; 235-conventional) were pooled for patient preference with 95% confidence interval. The Forest plot showed a pooled estimate of 31.23 [5.95, 163.87], showing a statistically significant number of patients favouring digital impressions. Results from 11 studies reported the time taken in 589 patients (278-digital; 311 conventional). The pooled estimate (2.72 [0.08, 5.32]) (95% confidence interval) showed a statistically significant increase in the time required to make digital impressions. The overall time taken in minutes for the interventions in the digital group in decreasing order were: LAVA Cos (8.14[3.64,12,26] (statistically significant); I tero (4.11[-1.02,9.24]; CEREC (0.34[-4.14,4.82]). There was an overall preference for digital impressions, although the time required is longer. The factors related to the digital system, the operator and the patient were studied, with recommendations forming a basis for possible hardware and software upgrades of the digital systems that can produce significant improvement in the acceptance rate for both the patient and the clinician.

Is there truly an increase in risk of cardiovascular and hematological adverse events with vascular endothelial growth factor receptor tyrosine kinase inhibitors?

ABSTRACTObjectives: Recent studies have shown an increase risk of cardiovascular and hematological adverse events associated with vascular endothelial growth factor tyrosine kinase inhibitors (VEGF-TKIs). The authors hypothesize that the original studies may have produced exaggerated results because of the small baseline risks involved.Methods: A meta-analysis that included 71 trials, 8 different VEGFR-TKIs, and 11 adverse events were re-analyzed. The outcome of interest was re-defined as the complementary outcome (i.e. remaining free of an adverse event). The inverse variance heterogeneity model was used to pool the effect size.Results: VEGFR-TKIs decreased the risk of remaining free of hypertension by 7% (RR 0.93; 95%CI:0.88–0.97). Specific VEGFR-TKIs; pazopanib, regorafenib, and nintedanib were associated with a decrease risk of remaining free of an arterial thrombotic event (RR 0.96; 95%CI:0.93–0.99), thrombocytopenia (RR 0.91; 95%CI:0.89–0.93), and bleeding (RR 0.96; 95%CI:0.93–0.99) respectively. VEGFR-TKIs were not associated with the thrombotic event, myocardial infarction, stroke, venous thrombotic event, pulmonary embolism, left ventricular dysfunction, or QTc interval prolongation.Conclusion: VEGFR-TKIs are associated with a small increase in the risk of patients developing hypertension, arterial thrombotic events, thrombocytopenia, and bleeding. Previous studies overestimated the actual risk associated with VEGFR-TKIs by analyzing the outcome with the lower baseline risk.

Obesity and cardiovascular outcomes: another look at a meta-analysis of Mendelian randomization studies

This study used the inverse variance heterogeneity (IVhet) model to conduct a reanalysis of a recent meta-analysis that reported a positive association, based on the random-effects (RE) model, between obesity...

Increasing antibiotic resistance in Clostridioides difficile: A systematic review and meta-analysis

BackgroundDecreases in clinical response of Clostridioides difficile to antibiotics used for its treatment have raised concerns regarding antibiotic resistance. We conducted a systematic review and meta-analysis to study the resistance rates of C. difficile to various antibiotics over time. MethodsWe systematically searched MEDLINE, Embase, and Web of Science from inception through 03/31/2017 for observational studies assessing antibiotic resistance rates in C. difficile. Weighted summary estimates were calculated using inverse variance heterogeneity models [MetaXL software (v. 5.3)]. A priori subgroup analyses were done (by study year, continent, susceptibility testing method, origin of isolates); ribotype 027 strains were analyzed separately. ResultsFrom 1982 to 2017, 60 studies (8336 isolates) were analyzed. Fifty-three studies reported vancomycin resistance; weighted pooled resistance (WPR), 2.1% (95% CI, 0%–5.1%; I2 = 95%). Fifty-five studies reported metronidazole resistance; WPR, 1.9% (95% CI, 0.5%–3.6%; I2 = 89%). Compared to the period before 2012, vancomycin resistance increased by 3.6% (95% CI, 2.9%–4.2%; P < 0.001) after 2012, and metronidazole resistance decreased by 0.8% (95% CI, 0.1%–1.5%; P = 0.02). No isolates were resistant to fidaxomicin. ConclusionResistance of C. difficile to vancomycin is increasing, with a smaller, declining resistance to metronidazole; there is significant heterogeneity between studies. Ongoing monitoring of resistance to commonly used antibiotics is required.

Comparative effects of lipid lowering, hypoglycemic, antihypertensive and antiplatelet medications on carotid artery intima-media thickness progression: a network meta-analysis

BackgroundCarotid artery intima-media thickness (cIMT) progression is a surrogate marker of atherosclerosis with a high predictive value for future CVD risk. This study evaluates the comparative efficacies of lipid lowering, hypoglycemic, antihypertensive and antiplatelet medications on cIMT progression.MethodsWe conducted a network meta-analysis (NMA) to evaluate the relative efficacies of several drug classes in modifying cIMT progression. After a literature search in several electronic databases, studies were selected by following predetermined eligibility criteria. An inverse variance-heterogeneity model was used for NMA. Sensitivity analyses were performed to check the reliability of the overall NMA, and transitivity analyses were performed to examine the effects of modifiers on the NMA outcomes.ResultsData were taken from 47 studies (15,721 patients; age: 60.2 years [95% confidence interval (CI) 58.8, 61.6]; BMI: 27.2 kg/m2 [95% CI 26.4, 28.0]; and gender: 58.3% males [95% CI 48.3, 68.3]). Treatment duration was 25.8 months [95% CI 22.9, 28.7]. Of the 13 drug classes in the network, treatment with phosphodiesterase III inhibitors was the most effective in retarding annual mean cIMT against network placebo (weighted mean difference (WMD) − 0.059 mm [95% CI − 0.099, − 0.020) followed by the calcium channel blockers (WMD − 0.055 mm [95% CI − 0.099, 0.001]) and platelet adenosine diphosphate inhibitors (WMD − 0.033 mm [95% CI − 0.058, 0.008]). These 3 drug classes also attained the same positions when the NMA was conducted by using first-year changes in mean cIMT. In transitivity analyses, longer treatment duration, higher body mass index (BMI), and a higher baseline cIMT were found to be independently associated with a lesser reduction in annual mean cIMT. However, in a multivariate analysis with these 3 modifiers, none of these factors was significantly associated with annual change in mean cIMT. In the placebo group, age was inversely associated with annual change in mean cIMT independently.ConclusionPhosphodiesterase III inhibitors and calcium channel blockers are found more effective than other drug classes in retarding cIMT progression. Age, BMI, and baseline cIMT may have some impact on these outcomes.

What Target Volume Should be Considered when Irradiating the Regional Nodes in Breast Cancer? Results of a Network – Meta-Analysis

Radiation treatment to the regional nodes results in an improvement in survival in breast cancer according to a meta-analysis of randomized trials. However different volumes were targeted in these studies (breast or chestwall only (WBI/CWI), inclusion of the medial supraclavicular region and axillary apex (MS+WBI/CWI), additional inclusion of the internal mammary chain (IM+MS+WBI/CWI). The benefit of treating the medial supraclavicular region and axillary apex compared to tangential breast or chestwall irradiation remains unclear. A literature search was conducted identifying trials for adjuvant radiation volumes in nodal irradiation after breast surgery and axillary treatment. Events and effect sizes were extracted from the publications for the endpoints of overall survival (OS), breast cancer-specific survival (BCSS), disease-free survival (DFS), distant metastasis-free survival (DMFS) and loco-regional control (LRC). A network meta-analysis was performed using MetaXL V5.3 with the inverse variance heterogeneity model We found two randomized studies (n=5836) comparing comprehensive nodal irradiation to sole breast treatment as well as one randomized (n=1407) and one prospective cohort study (n=3377) analyzing the additional treatment of the internal mammary chain against sole local and supraclavicular and axillary apex radiation. Compared to WBI/CWI alone the treatment of IM+MS+WBI/CWI (HR=0,88; CI:0,78-0,99; p=0,036) results in improved OS unlike MS+WBI/CWI (HR=0,99; CI:0,86-1,14; p=0,89). These results are confirmed in BCSS: IM+MS+WBI/CWI (HR=0,82; CI:0,72-0,92; p=0,002) and MS+WBI/CWI (HR=0,96; CI:0,79-1,18; p=0,69). PFS is significantly improved with the treatment of MS+WBI/CWI (OR=0,83; CI:0,71-0,97; p=0,019). Both nodal treatment volumes improve LRC (MS+WBI/CWI OR=0,74; CI:0,62-0,87; p=0,004 and IM+MS+WBI/CWI OR=0,60; CI:0,43-0,86; p<0,001). Yet only the internal mammary nodes provide a benefit in DMFS (MS+WBI/CWI HR=0,97; CI:0,81-1,16; p=0,74 and IM+MS+WBI/CWI HR=0,84; CI:0,75-0,94; p=0,002). Expanding the radiation field to the axillary apex and supraclavicular nodes after axillary node dissection reduced loco-regional recurrences without improvement in overall and cancer-specific survival. A prolongation in survival due to regional nodal irradiation is achieved when the internal mammary chain is included. One explantion could be the reduction of distant metastasis.

Retinopathy of Type 1 Diabetes in Arab Countries: Systematic Review and Meta-Analysis

Aims: To conduct a systematic review and meta-analysis of retinopathy prevalence in patients with type 1 diabetes (T1D) in 22 Arab countries. Methods: We systematically searched 4 different literature databases (PubMed, Science Direct, Web of Science and Embase), from the date of inception until December 2017, to collect all the information about patients with T1D who developed retinopathy complications; for statistical analysis, we used MetaXL to evaluate the pooled prevalence estimate and the subgroup prevalence estimates employing double arcsine transformation and inverse variance heterogeneity models. Results: Our search strategy returned 475 studies, of which 39 met our inclusion criteria; of those, 16 were eligible for meta-analysis that were captured only in 15 Arab countries, through 45 years (1969–2014). The number of retinopathy patients was 396 out of 1,931 patients with T1D. The prevalence of retinopathy was 19% (95% CI 10–28%). Substantial heterogeneity was observed (Q 240.78, p < 0.0001, I² 93.77%, 95% CI 91.35–95.52%); however, no single study considerably affected the overall pooled prevalence estimate. Conclusion: Almost one fifth of T1D patients in 15 Arab countries have diabetic retinopathy, therefore it is important to improve the care of patients with T1D and in Arab countries to avoid the development of such a devastating complication.

Systematic review with meta-analysis: anxiety and depression in children and adolescents with inflammatory bowel disease.

The co-existence of psychological problems and paediatric inflammatory bowel disease (IBD) is receiving increasing attention. Most studies investigated anxiety and depression, with prevalence rates varying from 0% to 50%. A systematic review is necessary to provide clear insight into the prevalence of anxiety and depression in paediatric IBD. To systematically evaluate available data on the prevalence of anxiety and depressive symptoms and disorders in paediatric IBD (aged 6-18years). Comprehensive searches were performed in Embase, Medline Ovid, Web of Science, Cochrane, PubMed, PsychInfo Ovid, and Google scholar for studies published from 1994 to 2017. Pooled prevalence rates were calculated using inverse variance heterogeneity models. Meta-regression was used to study if disease type, disease activity and gender influence prevalence. Twenty-eight studies (N=8107, mean age: 14.3) were identified. Pooled prevalence estimates were 16.4% (95% confidence interval [CI] 6.8%-27.3%) for anxiety symptoms and 4.2% (95% CI 3.6%-4.8%) for anxiety disorders. Pooled prevalence estimates were 15.0% (95% CI 6.4%-24.8%) for depressive symptoms and 3.4% (95% CI 0%-9.3%) for depressive disorders. Meta-regression showed no influence of disease type or gender on these prevalence rates, but studies with a higher percentage of active disease had a higher rate of depressive symptoms. The described pooled prevalence of anxiety and depressive symptoms is lower than in adult IBD. However, due to varying instruments/cut-offs for measuring symptoms and few studies investigating disorders, the results should be interpreted with caution. Cross-cultural use of the same instruments is needed to gain better insight into prevalence rates.

Pharmacological interventions for premature ejaculation: a mixed-treatment comparison network meta-analysis of randomized clinical trials.

Premature ejaculation (PE) is the most common sexual dysfunction in men. The present study is a network meta-analysis of drugs used for treating PE. Electronic databases were searched for randomized controlled trials comparing medical interventions with either placebo or with other active drugs in patients with PE. Inverse variance heterogeneity model was used for mixed-treatment comparisons. Intravaginal ejaculatory latency time (IELT) and adverse events were the main outcome measures. A total of 44 studies were included in the meta-analysis. Dapoxetine 30 and 60 mg, tadalafil, sildenafil, paroxetine with sildenafil, topical lidocaine, dapoxetine 30 mg with mirodenafil, vardenafil, fluoxetine, and tadalafil, pindolol with paroxetine, tramadol, topical lidocaine with tadalafil, paroxetine with tadalafil, and topical eutectic mixture of local anesthetics were associated with a significant increase in IELT. Similarly, dapoxetine 60 mg, venlafaxine, fluoxetine, tramadol at 25, 50, and 100 mg, and combined fluoxetine and tadalafil were associated with an increased risk of adverse events. Dapoxetine 30 mg has a high likelihood of being the "best" in the interventional pool. Dapoxetine at 30 mg could be used as the first-line agent in the management of PE.

Residential road traffic noise as a risk factor for hypertension in adults: Systematic review and meta-analysis of analytic studies published in the period 2011–2017

Multiple cross-sectional studies indicated an association between hypertension and road traffic noise and they were recently synthetized in a WHO systematic evidence review. However, recent years have seen a growing body of high-quality, large-scale research, which is missing from the WHO review. Therefore, we aimed to close that gap by conducting an updated systematic review and meta-analysis on the exposure-response relationship between residential road traffic noise and the risk of hypertension in adults. Studies were identified by searching MEDLINE, EMBASE, the Internet, conference proceedings, reference lists, and expert archives in English, Russian, and Spanish through August 5, 2017. The risk of bias for each extracted estimate and the overall quality of evidence were evaluated using a list of predefined safeguards against bias related to different study characteristics and the Grading of Recommendations Assessment, Development and Evaluation system, respectively. The inverse variance heterogeneity (IVhet) model was used for meta-analysis. The possibility of publication bias was evaluated by funnel and Doi plots, and asymmetry in these was tested with Egger's test and the Luis Furuya-Kanamori index, respectively. Sensitivity analyses included leave-one-out meta-analysis, subgroup meta-analysis with meta-regressions, and non-linear exposure-response meta-analysis. Based on seven cohort and two case-control studies (n = 5 514 555; 14 estimates; Lden range ≈ 25–90 dB(A)), we found “low” evidence of RR per 10 dB(A) = 1.018 (95% CI: 0.984, 1.053), moderate heterogeneity (I2 = 46%), and no publication bias. In the subgroup of cohort studies, we found “moderate” evidence of RR per 10 dB(A) = 1.018 (95% CI: 0.987, 1.049), I2 = 31%, and no publication bias. In conclusion, residential road traffic noise was associated with higher risk of hypertension in adults, but the risk was lower than previously reported in the systematic review literature.

Direct mechanical thrombectomy in tPA-ineligible and -eligible patients versus the bridging approach: a meta-analysis

BackgroundWhether pretreatment with intravenous thrombolysis prior to mechanical thrombectomy (IVT+MTE) adds additional benefit over direct mechanical thrombectomy (dMTE) in patients with large vessel occlusions (LVO) is a matter of debate.MethodsThis...

Pulmonary Vein Stenosis in Infants: A Systematic Review, Meta-Analysis, and Meta-Regression

To quantify outcomes of infants (<1 year of age) diagnosed with pulmonary vein stenosis (PVS). MEDLINE (PubMed), Scopus, and Web of Science were searched through February 1, 2017, with no language restrictions. Publications including infants diagnosed with primary PVS, defined as the absence of preceding intervention(s), were considered. The study was performed according to Meta-analysis of Observational Studies in Epidemiology guidelines, the Systematic Reviews, and Meta-Analysis checklist, and registered prospectively. The quality of selected reports was critically examined. Data extraction was independently performed by multiple observers with outcomes agreed upon a priori. Data were pooled using an inverse variance heterogeneity model with incidence of mortality the primary outcome of interest. Forty-eight studies of 185 infants were included. Studies were highly diverse with regards to the participants, interventions, and outcomes reported. The median (range) age at diagnosis was 5.0 (0.1-11.6) months. Pooled mortality was 58.5% (95% CI 49.8%-67.0%, I2 = 21.4%). We observed greater mortality incidence among infants with 3 or 4 vein stenoses than in those with 1 or 2 vein stenoses (83.3% vs 36.1%; P < .01). We observed greater mortality among infants with bilateral than unilateral disease (78.7% vs 26.0%; P < .01). Studies of primary PVS during infancy are highly variable in their methodological quality and estimates of clinical outcomes; therefore, estimates of prognosis remain uncertain. Multicenter, interdisciplinary collaborations, including alignment of key outcome measurements, are needed to answer questions beyond the scope of available data.

Radiotherapy May Offer a Recurrence and Survival Benefit in Rectal Cancers Treated Surgically with Transanal Endoscopic Microsurgery: A Systematic Review and Meta-analysis

Several studies report outcomes of Transanal Endoscopic Microsurgery (TEMS) surgery in combination with radiotherapy, however the combination of those treatments is provided mostly on an adhoc individual basis and the role of radiotherapy remains unclear. The aim of this study was to identify the effect of neo-adjuvant or adjuvant radiotherapy in the oncological outcomes of rectal cancer treated surgically with TEMS. We performed a systematic review of the literature on MEDLINE and Pubmed databases. Data were extracted by two independent reviewers and meta-analyzed using an inverse variance heterogeneity model to calculate overall (pooled) effect sizes for survival or recurrence of disease against neo+/-adjuvant treatment. A total of 48 studies were included in the qualitative meta-analysis which included 3,285 patients with rectal cancer. The overall survival odds ratio (OR), was 9.39 (95% CI=6.1-14.4) with a Cochran's Q variable of 151.7 on 47 degrees of freedom (d.f.) (p=0.000). Recurrence-free OR was 8.7 (95%CI=6.58-11.44) with a Cochran's Q variable of Q=145.2 on 44 d.f. (p=0.000). Studies which contained more than 10% of pT3 tumours, and provided neo+/-adjuvant treatment in more than 35% of cases, were associated with survival benefit, as demonstrated by an overall odds of survival of 32.2 (95%CI=16.3-63.5, p=0.001, Q=8.4, p=0.21). Studies that contained more than 10% of pT3 tumours and provided neo+/-adjuvant treatment in more than 20% of the cases had an overall effect size of recurrence-free odds of 20.23 (95%CI=13.84-29.57, p=0.000, Q=2.18, p=0.54). There seems to be a benefit from radiotherapy on overall survival and recurrence-free odds, which is more apparent in cohorts with more than 10% of pT3 tumours. Our results suggest that neo-adjuvant or adjuvant radiotherapy should be considered for inclusion in formal treatment protocols for rectal cancers treated with TEMS as they offer a recurrence and survival benefit.

Systematic review and meta-analysis on outcome differences among patients with TICI2b versus TICI3 reperfusions: success revisited

ObjectiveA reperfusion quality of thrombolysis in cerebral infarction (TICI)≥2b has been set as the therapeutic angiography target for interventions in patients with acute ischaemic stroke. This study addresses whether the...

Overnutrition among schoolchildren in India: a review and meta-analysis

Abstract Background Obesity continues to be a significant public health concern in India. As half of overweight adults were also overweight during their childhood, estimates of the burden of overweight or obesity among Indian schoolchildren would help to forecast the obesity epidemic among adults. In this context, we did a review and meta-analysis of studies published during past 10 years. Methods Studies done during 2005–15 that used WHO cut-off points to assess overnutrition (overweight and obesity) among Indian children aged 6–19 years from rural or urban schools were included. Studies that used other diagnostic criteria, focused on specific subgroups such as males, or were done in affluent schools were excluded. Considering the heterogeneity of the studies, random effects and inverse variance heterogeneity models were used for estimating pooled prevalence using MetaXL (version 2.2) software. Findings 21 studies involving both boys and girls, covering 81 716 schoolchildren and 11 Indian states, were included. The prevalence of overnutrition in the individual studies ranged between 1·5% and 32·2%. The pooled prevalence estimates of overnutrition in the random effects and inverse variance heterogeneity models were 11·15% (95% CI 8·98–13·51) and 10·56% (5·09–16·74), respectively. In subgroup analysis, boys and urban students had a higher burden of overnutrition than their counterparts. However, the difference in overnutrition prevalence across gender groups was lower than the urban–rural difference. Most of the studies included were of moderate quality and there was heterogeneity among studies. Interpretation One in nine schoolchildren suffering from overnutrition is a concern as India suffers a dual burden of undernutrition and overnutrition, representing the inequitable distribution of health. Interventions to reduce overnutrition burden and monitoring of overnutrition with the use of a country-specific standard tool is warranted. Funding None.