Cumulative meta-analysis of clinical trials builds evidence for exemplary medical care

Genetic association of SLC6A3 (dopamine transporter) gene polymorphisms with personality disorders and substance abuse disorders: a systematic review and meta-analysis

INTRODUCTION

Personality disorders (PD) are characterized by socially dysfunctional behavioral patterns that affect patients and show higher incidence rates within families. Substance abuse disorders (SAD) are exemplified by extensive and prolonged use of substances, including alcohol, nicotine, or illegal drugs. Genetic predisposition for both PD and SAD has been reported to involve gene variants regulating dopaminergic pathways. Yet, discrepancy among reported results necessitates further elucidation of potential hereditary-related risk factors. Because both disorders impose a societal burden, knowledge on the impact of certain genetic backgrounds on these diseases could help develop evidence-based strategies for efficacious treatment approaches.

MATERIALS AND METHODS

In the present study a systematic review was performed, and the association between dopamine transporter gene polymorphism (SLC6A3), particularly rs28363170 entailing a 40-bp variable number tandem repeat, and PD as well as SAD was investigated recruiting meta-analysis approach.

RESULTS

Initial literature search for PD yielded 1577, from which nine fulfilled eligibility criteria to be used in a meta-analysis including 729 cases and 2113 controls. From the 934 studies retrieved for SAD, only 29 articles with 5221 cases and 4822 controls were used for meta-analysis. A statistically significant association was seen between rs28363170 (for the 9-repeat allele) and PD in European populations according to the co-dominant mode of inheritance. For SAD no statistically significant correlation under any mode of inheritance was observed. There was no indication of time-trend phenomena.

CONCLUSION

Our findings demonstrate the association of SLC6A3 gene polymorphism with PD, thus underling the need to understand neurobiological mechanisms inherent to the above disorders to guide treatment strategies under the perspective of personalized medicine.

Association between low-calorie sweetener consumption during pregnancy and child health: A systematic review and meta-analysis

We examined the association between low-calorie sweeteners (LCS) consumption during preconception, pregnancy, and breastfeeding and child health outcomes. A systematic search of electronic databases in PubMed, Embase, Cumulated Index to Nursing and Allied Health Literature, the Cochrane Library, Scopus, Web of Science, PsycINFO, ProQuest Health and Medical, ClinicalTrials.gov, and Google Scholar was conducted up to 21 September 2023. A random effects model with restricted maximum likelihood estimation was used for the meta-analysis. Seventeen eligible studies were included. The standardised mean difference (SMD) and 95% confidence interval (CI) in birth weight between those who frequently consumed LCS (≥1 serve/day) during pregnancy and those who did not consume LCS was 0.04 (0.00, 0.08) (four cohort studies). Any LCS consumption during pregnancy compared with no consumption was not associated with birth weight [SMD (95% CI) = 0.03 (-0.03, 0.08)] (four cohort studies). Any LCS consumption during pregnancy was not associated with body mass index z-scores. The weighted mean difference (95% CI) was 0.00 (-0.05, 0.06) at birth, 0.06 (-0.29, 0.40) at 6 months, -0.04 (-0.19, 0.10) at 1 year, 0.00 (-0.16, 0.17) at 3 years, and 0.10 (-0.15, 0.34) at 7 years of the child age, compared with no intake (five cohort studies). The odds of being overweight at 1 year among children exposed to LCS during pregnancy was 1.19 (OR [95% CI]: 1.19 [0.81, 1.58]) compared with unexposed children (two cohort studies). The effect sizes were not precise for all the outcomes as the 95% CI indicated the effect estimates could range from small protective to a higher risk. The effect of LCS consumption on child behaviour and cognition was inconsistent. There is not enough evidence to confirm LCS consumption during pregnancy affects birth weight and risk of overweight in children. However, frequent consumption increased birth weight and the risk of overweight at different ages, though the effects were imprecise. More robust research evidence is required as the quality of evidence is low.

Prevalence of and factors associated with potentially redundant randomized controlled trials: a cross-sectional study

OBJECTIVES

To investigate the prevalence of meta-analyses containing potentially redundant randomized controlled trials (RCTs) and the factors associated with the presence of redundancy.

STUDY DESIGN AND SETTING

This is a cross-sectional study, based on a random sample of references (n = 4500) that were published during 2020 and 2021, indexed in PubMed, Embase, or the Cochrane Database of Systematic Reviews, and retrieved through comprehensive searches using terms about systematic reviews and meta-analysis. From each systematic review, one meta-analysis fulfilling all the following criteria, if available, was included in this study: (1) assessing the effect of the intervention on a primary outcome of the systematic review; (2) combining RCTs only. The primary outcome was prevalence of meta-analyses containing potentially redundant RCTs. Potentially redundant RCTs referred to the trials that started 1 year after the overall effect estimate from cumulative meta-analysis had been statistically robust, as determined by trial sequential analysis when appropriate. The number of potentially redundant trials (if any) in each eligible meta-analysis and the number of participants involved in those trials were documented and contrasted across groups. Logistic regression analysis was conducted to explore the factors associated with presence of potential redundancy.

RESULTS

Of the 448 eligible meta-analyses, 57 (12.7%, 95% confidence interval (CI) 9.8-16.2%) contained potentially redundant RCTs. When limited to the 333 low-heterogeneity meta-analyses, the prevalence was 17.1% (95% CI 13.5-21.5%). The total number of potentially redundant RCTs was 295 (involving 85,385 participants), accounting for 38.5% of the RCTs (and 30.3% of the participants) included in the 57 meta-analyses. In these meta-analyses, the median number of potentially redundant RCTs and the participants involved were 2 (range: 1-50) and 352 (range: 17-26997), respectively. Potentially redundant RCTs were more likely to be present in the meta-analyses evaluating pharmaceutical intervention (odds ratio [OR] 2.31, 95% CI 1.16-4.49), assessing efficacy outcomes (OR 7.25, 95% CI 0.85-61.87), containing more than 5 RCTs (OR 6.47, 95% CI 3.22-12.99), or with the earliest RCT reporting statistically significant effect estimate (OR 5.30, 95% CI 2.64-10.64).

CONCLUSION

This study found that 12.7% to 17.1% of recently published meta-analyses contained potentially redundant RCTs, highlighting the importance of conducting or examining systematic reviews of existing evidence to justify new RCTs. More importantly, the study identified some scenarios in which redundancy was more likely to occur and thus has implications for trialists, funding agencies, ethics committees, and journal editors.

Determining the conclusiveness of a meta-analysis

The pursuit of conclusive evidence related to an unanswered foreground (decision-making) question has been the driving factor behind multiple ongoing and planned randomized controlled trials as well as meta-analyses. However, a fundamental challenge lies in establishing robust methods for ascertaining whether a collection of synthesized trials has yielded a definitive answer to that foreground question through the process of meta-analysis. This article explores the evolution of methods that attempt to address this challenge. These methods have primarily focused on defining and measuring the sufficiency and stability of evidence within a meta-analytic context. Cumulative meta-analysis and trial sequential analysis are the tools currently used, but they both come with limitations and challenges. We further discuss methods aimed at evaluating the evolution of effects over time more directly, such as the recursive cumulative meta-analysis. The latter method can be considered a better alternative, as it serves to demonstrate whether there is a true underlying treatment effect to which the meta-analysis is converging. However, recursive cumulative meta-analysis falls short of a specific indicator that establishes whether convergence has been reached. We coin the term exit for a meta-analysis where convergence can be demonstrated. Developing methods to determine the exit status of a meta-analysis is the next priority in research synthesis methods, as it will indicate that the research journey has concluded on a particular foreground question with no expectation of a different result with the addition of future trials.

Bacillus species as tools for biocontrol of plant diseases: A meta-analysis of twenty-two years of research, 2000-2021

The traditional way of dealing with plant diseases has been the use of chemical products, but these harm the environment and are incompatible with the global effort for sustainable development. The use of Bacillus and related species in the biological control of plant diseases is a trend in green agriculture. Many studies report the positive effect of these bacteria, but a synthesis is still necessary. So, the objective of this work is to perform a meta-analysis of Bacillus biocontrol potential and identify factors that drive its efficacy. Data were compiled from articles published in journals listed in two of the main scientific databases between 2000 and 2021. Among 6159 articles retrieved, 399 research papers met the inclusion criteria for a systematic review. Overall, Bacilli biocontrol agents reduced disease by 60% compared to control groups. Furthermore, experimental tests with higher concentrations show a strong protective effect, unlike low and single concentration essays. Biocontrol efficacy also increased when used as a protective inoculation rather than therapeutic inoculation. Inoculation directly in the fruit has a greater effect than soil drenching. The size of the effect of Bacillus-based commercial products is lower than the newly tested strains. The findings presented in this study confirm the power of Bacillus-based bioinoculants and provide valuable guidance for practitioners, researchers, and policymakers seeking effective and sustainable solutions in plant disease management.

Complement-activating donor-specific anti-HLA antibodies in solid organ transplantation: systematic review, meta-analysis, and critical appraisal

Introduction

Several studies have investigated the impact of circulating complement-activating anti-human leukocyte antigen donor-specific antibodies (anti-HLA DSAs) on organ transplant outcomes. However, a critical appraisal of these studies and a demonstration of the prognostic value of complement-activating status over anti-HLA DSA mean fluorescence intensity (MFI) level are lacking.

Methods

We conducted a systematic review, meta-analysis and critical appraisal evaluating the role of complement-activating anti-HLA DSAs on allograft outcomes in different solid organ transplants. We included studies through Medline, Cochrane, Scopus, and Embase since inception of databases till May 05, 2023. We evaluated allograft loss as the primary outcome, and allograft rejection as the secondary outcome. We used the Newcastle-Ottawa Scale and funnel plots to assess risk of bias and used bias adjustment methods when appropriate. We performed multiple subgroup analyses to account for sources of heterogeneity and studied the added value of complement assays over anti-HLA DSA MFI level.

Results

In total, 52 studies were included in the final meta-analysis (11,035 patients). Complement-activating anti-HLA DSAs were associated with an increased risk of allograft loss (HR 2.77; 95% CI 2.33-3.29, p<0.001; I²=46.2%), and allograft rejection (HR 4.98; 95% CI 2.96-8.36, p<0.01; I²=70.9%). These results remained significant after adjustment for potential sources of bias and across multiple subgroup analyses. After adjusting on pan-IgG anti-HLA DSA defined by the MFI levels, complement-activating anti-HLA DSAs were significantly and independently associated with an increased risk of allograft loss.

Discussion

We demonstrated in this systematic review, meta-analysis and critical appraisal the significant deleterious impact and the independent prognostic value of circulating complement-activating anti-HLA DSAs on solid organ transplant risk of allograft loss and rejection.

Temporal Trends and Lesion Sets for Persistent Atrial Fibrillation Ablation: A Meta-Analysis With Trial Sequential Analysis and Meta-Regression

BACKGROUND

Ablation for persistent atrial fibrillation (PsAF) has been performed for over 20 years, although success rates have remained modest. Several adjunctive lesion sets have been studied but none have become standard of practice. We sought to describe how the efficacy of ablation for PsAF has evolved in this time period with a focus on the effect of adjunctive ablation strategies.

METHODS

Databases were searched for prospective studies of PsAF ablation. We performed meta-regression and trial sequential analysis.

RESULTS

A total of 99 studies (15 424 patients) were included. Ablation for PsAF achieved the primary outcome (freedom of atrial fibrillation/atrial tachycardia rate at 12 months follow-up) in 48.2% (5% CI, 44.0-52.3). Meta-regression showed freedom from atrial arrhythmia at 12 months has improved over time, while procedure time and fluoroscopy time have significantly reduced. Through the use of cumulative meta-analyses and trial sequential analysis, we show that some ablation strategies may initially seem promising, but after several randomized controlled trials may be found to be ineffective. Trial sequential analysis showed that complex fractionated atrial electrogram ablation is ineffective and further study of this treatment would be futile, while posterior wall isolation currently does not have sufficient evidence for routine use in PsAF ablation.

CONCLUSIONS

Overall success rates from PsAF ablation and procedure/fluoroscopy times have improved over time. However, no adjunctive lesion set, in addition to pulmonary vein isolation, has been conclusively demonstrated to be beneficial. Through the use of trial sequential analysis, we highlight the importance of adequately powered randomized controlled trials, to avoid reaching premature conclusions, before widespread adoption of novel therapies.

Methylphenidate for children and adolescents with attention deficit hyperactivity disorder (ADHD)

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is one of the most commonly diagnosed and treated psychiatric disorders in childhood. Typically, children and adolescents with ADHD find it difficult to pay attention and they are hyperactive and impulsive. Methylphenidate is the psychostimulant most often prescribed, but the evidence on benefits and harms is uncertain. This is an update of our comprehensive systematic review on benefits and harms published in 2015.

OBJECTIVES

To assess the beneficial and harmful effects of methylphenidate for children and adolescents with ADHD.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, three other databases and two trials registers up to March 2022. In addition, we checked reference lists and requested published and unpublished data from manufacturers of methylphenidate.

SELECTION CRITERIA

We included all randomised clinical trials (RCTs) comparing methylphenidate versus placebo or no intervention in children and adolescents aged 18 years and younger with a diagnosis of ADHD. The search was not limited by publication year or language, but trial inclusion required that 75% or more of participants had a normal intellectual quotient (IQ > 70). We assessed two primary outcomes, ADHD symptoms and serious adverse events, and three secondary outcomes, adverse events considered non-serious, general behaviour, and quality of life.

DATA COLLECTION AND ANALYSIS

Two review authors independently conducted data extraction and risk of bias assessment for each trial. Six review authors including two review authors from the original publication participated in the update in 2022. We used standard Cochrane methodological procedures. Data from parallel-group trials and first-period data from cross-over trials formed the basis of our primary analyses. We undertook separate analyses using end-of-last period data from cross-over trials. We used Trial Sequential Analyses (TSA) to control for type I (5%) and type II (20%) errors, and we assessed and downgraded evidence according to the GRADE approach.

MAIN RESULTS

We included 212 trials (16,302 participants randomised); 55 parallel-group trials (8104 participants randomised), and 156 cross-over trials (8033 participants randomised) as well as one trial with a parallel phase (114 participants randomised) and a cross-over phase (165 participants randomised). The mean age of participants was 9.8 years ranging from 3 to 18 years (two trials from 3 to 21 years). The male-female ratio was 3:1. Most trials were carried out in high-income countries, and 86/212 included trials (41%) were funded or partly funded by the pharmaceutical industry. Methylphenidate treatment duration ranged from 1 to 425 days, with a mean duration of 28.8 days. Trials compared methylphenidate with placebo (200 trials) and with no intervention (12 trials). Only 165/212 trials included usable data on one or more outcomes from 14,271 participants. Of the 212 trials, we assessed 191 at high risk of bias and 21 at low risk of bias. If, however, deblinding of methylphenidate due to typical adverse events is considered, then all 212 trials were at high risk of bias.

PRIMARY OUTCOMES

methylphenidate versus placebo or no intervention may improve teacher-rated ADHD symptoms (standardised mean difference (SMD) -0.74, 95% confidence interval (CI) -0.88 to -0.61; I² = 38%; 21 trials; 1728 participants; very low-certainty evidence). This corresponds to a mean difference (MD) of -10.58 (95% CI -12.58 to -8.72) on the ADHD Rating Scale (ADHD-RS; range 0 to 72 points). The minimal clinically relevant difference is considered to be a change of 6.6 points on the ADHD-RS. Methylphenidate may not affect serious adverse events (risk ratio (RR) 0.80, 95% CI 0.39 to 1.67; I² = 0%; 26 trials, 3673 participants; very low-certainty evidence). The TSA-adjusted intervention effect was RR 0.91 (CI 0.31 to 2.68).

SECONDARY OUTCOMES

methylphenidate may cause more adverse events considered non-serious versus placebo or no intervention (RR 1.23, 95% CI 1.11 to 1.37; I² = 72%; 35 trials 5342 participants; very low-certainty evidence). The TSA-adjusted intervention effect was RR 1.22 (CI 1.08 to 1.43). Methylphenidate may improve teacher-rated general behaviour versus placebo (SMD -0.62, 95% CI -0.91 to -0.33; I² = 68%; 7 trials 792 participants; very low-certainty evidence), but may not affect quality of life (SMD 0.40, 95% CI -0.03 to 0.83; I² = 81%; 4 trials, 608 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

The majority of our conclusions from the 2015 version of this review still apply. Our updated meta-analyses suggest that methylphenidate versus placebo or no-intervention may improve teacher-rated ADHD symptoms and general behaviour in children and adolescents with ADHD. There may be no effects on serious adverse events and quality of life. Methylphenidate may be associated with an increased risk of adverse events considered non-serious, such as sleep problems and decreased appetite. However, the certainty of the evidence for all outcomes is very low and therefore the true magnitude of effects remain unclear. Due to the frequency of non-serious adverse events associated with methylphenidate, the blinding of participants and outcome assessors is particularly challenging. To accommodate this challenge, an active placebo should be sought and utilised. It may be difficult to find such a drug, but identifying a substance that could mimic the easily recognised adverse effects of methylphenidate would avert the unblinding that detrimentally affects current randomised trials. Future systematic reviews should investigate the subgroups of patients with ADHD that may benefit most and least from methylphenidate. This could be done with individual participant data to investigate predictors and modifiers like age, comorbidity, and ADHD subtypes.

Osteocalcin serum concentrations and markers of energetic metabolism in pediatric patients. Systematic review and metanalysis

Background

Osteocalcin plays a role in glucose metabolism in mice, but its relevance in human energetic metabolism is controversial. Its relationship with markers of energetic metabolism in the pediatric population has not been systematically addressed in infants and adolescents.

Objective

This study aims to assess the mean differences between tOC, ucOC, and cOC among healthy children and children with type 1 or type 2 diabetes (T1D or T2D) and the correlation of these bone molecules with metabolic markers.

Methods

A systematic review and metanalysis were performed following PRISMA criteria to identify relevant observational studies published in English and Spanish using PubMed, Scopus, EBSCO, and Web of Science databases. The risk of bias was assessed using New Castle-Ottawa scale. Effect size measures comprised standardized mean difference (SMD) and Pearson correlations. Heterogeneity and meta-regressions were performed.

Results

The 20 studies included were of high quality and comprised 3,000 pediatric patients who underwent tOC, cOC, or ucOC measurements. Among healthy subjects, there was a positive correlation of ucOC with WC and weight, a positive correlation of tOC with FPG, HDL-c, WC, height, and weight, and a negative correlation between tOC and HbA1c. Among diabetic subjects, a negative correlation of ucOC with HbA1c and glycemia in both T1D and T2D was found and a negative correlation between tOC and HbA1c in T1D but not in T2D. The ucOC concentrations were lower in T2D, T1D, and patients with abnormal glucose status than among controls. The serum concentrations of tOC concentrations were lower among T1D than in controls. The patient's age, altitude, and HbA1c influenced the levels of serum tOC.

Conclusion

Osteocalcin is involved in energy metabolism in pediatric subjects because it is consistently related to metabolic and anthropometric parameters.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42019138283.

Pharmacological interventions for people with borderline personality disorder

BACKGROUND

Among people with a diagnosis of borderline personality disorder (BPD) who are engaged in clinical care, prescription rates of psychotropic medications are high, despite the fact that medication use is off-label as a treatment for BPD. Nevertheless, people with BPD often receive several psychotropic drugs at a time for sustained periods.

OBJECTIVES

To assess the effects of pharmacological treatment for people with BPD.

SEARCH METHODS

For this update, we searched CENTRAL, MEDLINE, Embase, 14 other databases and four trials registers up to February 2022. We contacted researchers working in the field to ask for additional data from published and unpublished trials, and handsearched relevant journals. We did not restrict the search by year of publication, language or type of publication.

SELECTION CRITERIA

Randomised controlled trials comparing pharmacological treatment to placebo, other pharmacologic treatments or a combination of pharmacologic treatments in people of all ages with a formal diagnosis of BPD. The primary outcomes were BPD symptom severity, self-harm, suicide-related outcomes, and psychosocial functioning. Secondary outcomes were individual BPD symptoms, depression, attrition and adverse events.

DATA COLLECTION AND ANALYSIS

At least two review authors independently selected trials, extracted data, assessed risk of bias using Cochrane's risk of bias tool and assessed the certainty of the evidence using the GRADE approach. We performed data analysis using Review Manager 5 and quantified the statistical reliability of the data using Trial Sequential Analysis.

MAIN RESULTS

We included 46 randomised controlled trials (2769 participants) in this review, 45 of which were eligible for quantitative analysis and comprised 2752 participants with BPD in total. This is 18 more trials than the 2010 review on this topic. Participants were predominantly female except for one trial that included men only. The mean age ranged from 16.2 to 39.7 years across the included trials. Twenty-nine different types of medications compared to placebo or other medications were included in the analyses. Seventeen trials were funded or partially funded by the pharmaceutical industry, 10 were funded by universities or research foundations, eight received no funding, and 11 had unclear funding. For all reported effect sizes, negative effect estimates indicate beneficial effects by active medication. Compared with placebo, no difference in effects were observed on any of the primary outcomes at the end of treatment for any medication. Compared with placebo, medication may have little to no effect on BPD symptom severity, although the evidence is of very low certainty (antipsychotics: SMD -0.18, 95% confidence interval (CI) -0.45 to 0.08; 8 trials, 951 participants; antidepressants: SMD -0.27, 95% CI -0.65 to 1.18; 2 trials, 87 participants; mood stabilisers: SMD -0.07, 95% CI -0.43 to 0.57; 4 trials, 265 participants). The evidence is very uncertain about the effect of medication compared with placebo on self-harm, indicating little to no effect (antipsychotics: RR 0.66, 95% CI 0.15 to 2.84; 2 trials, 76 participants; antidepressants: MD 0.45 points on the Overt Aggression Scale-Modified-Self-Injury item (0-5 points), 95% CI -10.55 to 11.45; 1 trial, 20 participants; mood stabilisers: RR 1.08, 95% CI 0.79 to 1.48; 1 trial, 276 participants). The evidence is also very uncertain about the effect of medication compared with placebo on suicide-related outcomes, with little to no effect (antipsychotics: SMD 0.05, 95 % CI -0.18 to 0.29; 7 trials, 854 participants; antidepressants: SMD -0.26, 95% CI -1.62 to 1.09; 2 trials, 45 participants; mood stabilisers: SMD -0.36, 95% CI -1.96 to 1.25; 2 trials, 44 participants). Very low-certainty evidence shows little to no difference between medication and placebo on psychosocial functioning (antipsychotics: SMD -0.16, 95% CI -0.33 to 0.00; 7 trials, 904 participants; antidepressants: SMD -0.25, 95% CI -0.57 to 0.06; 4 trials, 161 participants; mood stabilisers: SMD -0.01, 95% CI -0.28 to 0.26; 2 trials, 214 participants). Low-certainty evidence suggests that antipsychotics may slightly reduce interpersonal problems (SMD -0.21, 95% CI -0.34 to -0.08; 8 trials, 907 participants), and that mood stabilisers may result in a reduction in this outcome (SMD -0.58, 95% CI -1.14 to -0.02; 4 trials, 300 participants). Antidepressants may have little to no effect on interpersonal problems, but the corresponding evidence is very uncertain (SMD -0.07, 95% CI -0.69 to 0.55; 2 trials, 119 participants). The evidence is very uncertain about dropout rates compared with placebo by antipsychotics (RR 1.11, 95% CI 0.89 to 1.38; 13 trials, 1216 participants). Low-certainty evidence suggests there may be no difference in dropout rates between antidepressants (RR 1.07, 95% CI 0.65 to 1.76; 6 trials, 289 participants) and mood stabilisers (RR 0.89, 95% CI 0.69 to 1.15; 9 trials, 530 participants), compared to placebo. Reporting on adverse events was poor and mostly non-standardised. The available evidence on non-serious adverse events was of very low certainty for antipsychotics (RR 1.07, 95% CI 0.90 to 1.29; 5 trials, 814 participants) and mood stabilisers (RR 0.84, 95% CI 0.70 to 1.01; 1 trial, 276 participants). For antidepressants, no data on adverse events were identified.

AUTHORS' CONCLUSIONS

This review included 18 more trials than the 2010 version, so larger meta-analyses with more statistical power were feasible. We found mostly very low-certainty evidence that medication may result in no difference in any primary outcome. The rest of the secondary outcomes were inconclusive. Very limited data were available for serious adverse events. The review supports the continued understanding that no pharmacological therapy seems effective in specifically treating BPD pathology. More research is needed to understand the underlying pathophysiologic mechanisms of BPD better. Also, more trials including comorbidities such as trauma-related disorders, major depression, substance use disorders, or eating disorders are needed. Additionally, more focus should be put on male and adolescent samples.

Placebo response rates in randomized controlled trials for perianal Crohn's disease: A systematic review and meta-analysis

BACKGROUND AND AIMS

Perianal fistulizing disease is a common complication of Crohn's disease (CD), for which new therapies are urgently needed. To assist design of clinical trials for novel therapeutics, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to quantify placebo rates and identify factors influencing them in perianal CD.

METHODS

We searched MEDLINE, EMBASE and CENTRAL from inception to June 2021. Eligible studies were placebo-controlled trials of pharmacological interventions for perianal CD (pCD). Placebo fistula response and remission rates for induction and maintenance trials were extracted and pooled using a random-effects model. Mixed-effects meta-regression was used to evaluate the impact of patient and study-level characteristics on point estimates.

RESULTS

In 17 RCTs (13 induction, 5 maintenance) the pooled placebo fistula response and remission rate for induction trials was 25% (95% CI 17-36%) and 17% (95% CI 11-25%), respectively. For maintenance trials, the pooled placebo fistula response and remission rate was 23% (95% CI 17-32%) and 19% (95% CI 14-25%), respectively. Trials enrolling patients with less disease activity and a higher proportion with ileal predominant disease were associated with significantly higher placebo response rates. Trials originating in Europe (compared to North America), therapies requiring perianal injection and a longer timepoint to measure remission were associated with higher placebo remission rates.

CONCLUSIONS

Placebo response and remission rates in pCD trials are influenced by patient and disease-related factors, as well as the type of intervention being studied. These contemporary rates will inform trial design for novel therapeutics.

Exercise and Cardiovascular Disease Risk Factors in Children and Adolescents With Obesity: A Systematic Review With Meta-Analysis of Randomized Controlled Trials

The purpose of this study was to examine the effects of exercise on cardiovascular disease (CVD) risk factors in children and adolescents with obesity. Randomized controlled trials (RCTs) of exercise ≥4 weeks in children and adolescents with obesity were included if one or more CVD risk factors were included as an outcome. Studies were retrieved by searching 7 electronic databases, cross-referencing, and expert review. Data were pooled using the inverse-variance heterogeneity (IVhet) model and strength of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) instrument. Thirty-nine studies representing 1548 participants (847 exercise, 701 control) met the inclusion criteria. Aerobic exercise improved 10 of 12 (83.3%) outcomes (P < .05 for all) while combined aerobic and strength training improved 5 of 8 (62.5%) outcomes (P < .05 for all). The strength of evidence ranged from "very low" to "moderate." It was concluded that aerobic exercise, as well as combined aerobic and strength training, is associated with improvements in multiple CVD risk factors among children and adolescents with obesity. However, the generally low strength of evidence suggests a need for future well-designed and conducted RCTs on the effects of exercise, especially strength training, in children and adolescents with obesity.

Benefits of more intensive versus less intensive blood pressure control. Updated trial sequential analysis

Outcome data from randomized trials which compared different blood pressure (BP) targets grew impressively after publication of recent trials. We conducted a cumulative updated trial sequential analysis of studies which compared a more versus less intensive BP control strategy, for a total of 60,870 randomized patients. The compared BP targets differed across the trials. Outcome measures were stroke, heart failure, myocardial infarction and cardiovascular death. The average duration of follow-up was 3.95 years and achieved systolic BP was 7.69 mmHg lower with the more intensive than the less intensive BP control strategy. The more intensive BP control strategy significantly reduced the risk of stroke (OR 0.79; 95% CI 0.67-0.93), heart failure (OR 0.73; 95% CI 0.55-0.96), myocardial infarction (OR 0.81; 95% CI 0.73-0.91) and cardiovascular death (OR 0.81; 95% CI 0.68-0.98) as compared to the less intensive strategy. In a trial sequential analysis, the more intensive BP control strategy provided conclusive benefits over the less intensive strategy on the risk of stroke, heart failure and myocardial infarction by definitely crossing the efficacy monitoring boundary. For cardiovascular death, the cumulative Z-curve of the sequential analysis touched the efficacy monitoring boundary, but did not cross it. In conclusion, data accrued from randomized trials conclusively demonstrate the superiority of a more intensive over a less intensive BP control strategy for the prevention of stroke, heart failure and myocardial infarction. Results also suggest a significant benefit, albeit not yet conclusive, of a more intensive over a less intensive strategy for prevention of cardiovascular death.

Clinical, Endoscopic, and Safety Placebo Rates in Induction and Maintenance Trials of Crohn's Disease: Meta-Analysis of Randomised Controlled Trials

BACKGROUND

Precision in estimating placebo rates is important for clinical trial design.

AIM

To quantify placebo rates across relevant endpoints in Crohn's disease [CD] trials and identify the factors influencing these rates in a contemporary meta-analysis.

METHODS

We searched MEDLINE, EMBASE, and CENTRAL from inception to March 2021. Eligible studies were placebo-controlled trials of pharmacological interventions for CD. Placebo response and remission rates for induction and maintenance trials were extracted and pooled by random-effects to quantify placebo rates across studies. Mixed-effects meta-regression was used to evaluate the effects of study-level characteristics on placebo rates.

RESULTS

In 125 studies [91 induction, 46 maintenance], placebo clinical remission and response rates for induction studies were 18% (95% confidence interval [CI] 16, 21%], and 32% [95% CI 29, 35%], respectively, and for maintenance studies were 28% [95% CI 23, 34%] and 30% [95% CI 24, 37%], respectively. Endoscopic remission and response rates in induction studies were 8% [95% CI 4, 18%] and 16% [95% CI 11, 23%], respectively. Trials enrolling patients with prior biologic exposure, longer disease duration, and higher CD activity index scores were associated with lower placebo clinical remission rates. Increased duration of follow-up, more follow-up visits, and a greater proportion of patients with colonic disease distribution were associated with higher clinical placebo rates.

CONCLUSIONS

Placebo remission and response rates in CD trials vary according to the phase of the trial, endpoint assessed, and induction or maintenance design. These contemporary estimates will help to inform future CD trial design.

ALL-IN meta-analysis: breathing life into living systematic reviews

Science is justly admired as a cumulative process ("standing on the shoulders of giants"), yet scientific knowledge is typically built on a patchwork of research contributions without much coordination. This lack of efficiency has specifically been addressed in clinical research by recommendations for living systematic reviews and against research waste. We propose to further those recommendations with ALL-IN meta-analysis: Anytime Live and Leading INterim meta-analysis. ALL-IN provides statistical methodology for a meta-analysis that can be updated at any time-reanalyzing after each new observation while retaining type-I error guarantees, live-no need to prespecify the looks, and leading-in the decisions on whether individual studies should be initiated, stopped or expanded, the meta-analysis can be the leading source of information. We illustrate the method for time-to-event data, showing how synthesizing data at interim stages of studies can increase efficiency when studies are slow in themselves to provide the necessary number of events for completion. The meta-analysis can be performed on interim data, but does not have to. The analysis design requires no information about the number of patients in trials or the number of trials eventually included. So it can breathe life into living systematic reviews, through better and simpler statistics, efficiency, collaboration and communication.

Association Between Anthropometric Risk Factors and Metabolic Syndrome Among Adults in India: A Systematic Review and Meta-Analysis of Observational Studies

Introduction

Several studies have explored the effect of anthropometric risk factors on metabolic syndrome. However, no systematic effort has explored the effect of overweight and obesity on the prevalence of metabolic syndrome in India. Thus, we undertook a meta-analysis to estimate the effect of anthropometric risk factors on the prevalence of metabolic syndrome.

Methods

We searched databases PubMed Central, EMBASE, MEDLINE, and Cochrane library and search engines ScienceDirect and Google Scholar, from January 1964 through March 2021. We used the Newcastle–Ottawa scale to assess the quality of published studies, conducted a meta-analysis with a random-effects model, and reported pooled odds ratios (OR) with 95% CIs.

Results

We analyzed 26 studies with a total of 37,965 participants. Most studies had good to satisfactory quality on the Newcastle–Ottawa scale. Participants who were overweight (pooled OR, 5.47; 95% CI, 3.70–8.09) or obese (pooled OR, 5.00; 95% CI, 3.61–6.93) had higher odds of having metabolic syndrome than those of normal or low body weight. Sensitivity analysis showed no significant variation in the magnitude or direction of outcome, indicating the lack of influence of a single study on the overall pooled estimate.

Conclusion

Overweight and obesity are significantly associated with metabolic syndrome. On the basis of evidence, clinicians and policy makers should implement weight reduction strategies among patients and the general population.

A systematic review and meta-analysis of the effect of statin treatment on sVCAM-1 and sICAM-1

BACKGROUND AND AIMS

Statins might prevent cell adhesion to the endothelium, a key step in atherosclerosis. We conducted a systematic review and meta-analysis of the effect of statins on soluble vascular (sVCAM-1) and intercellular (sICAM-1) adhesion molecule 1.

METHODS

A systematic literature search was conducted in PubMed, Web of Science, and Scopus, from inception to July 2021. Risk of bias and certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for analytical studies and GRADE, respectively.

RESULTS

Statins significantly reduced both sVCAM-1 (standard mean difference, SMD=-0.28, 95% CI -0.44 to -0.12, p=0.001; 46 treatment arms; low certainty of evidence) and sICAM-1 (SMD=-0.75, 95% CI -1.00 to -0.50, p<0.001; 61 treatment arms; moderate certainty of evidence) concentrations. In sensitivity analysis, the SMD values were not modified when individual studies were sequentially removed. There were significant associations between SMD and publication year and, for sICAM-1, statin-induced changes in HDL-cholesterol. In subgroup analysis, the lowering effect was significant with liphophilic, but not hydrophilic, statins, and similar, for sICAM-1, in participants with or without clinically overt atherosclerosis.

CONCLUSIONS

Statins significantly lower sVCAM-1/sICAM-1. Prospective studies are required to determine whether this mediates their atheroprotective effects (PROSPERO registration number: CRD42021276825).

Clinical relevance of Tai Chi on pain and physical function in adults with knee osteoarthritis: An ancillary meta-analysis of randomized controlled trials

The clinical relevance of Tai Chi on pain, stiffness, and physical function in adults with knee osteoarthritis (KOA) has not been established. Therefore, the purpose of the current study was to address this gap. Eight randomized controlled trials from a recent meta-analysis representing 407 participants (216 Tai Chi, 191 control) in adults ≥18 years of age with KOA and included the assessment of pain, stiffness, and physical function using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) were assessed. The inverse variance heterogeneity model (IVhet) was first used to pool standardized mean difference effect sizes (ES) for each outcome. Clinical relevance, i.e., number-needed-to treat (NNT) ≤10 and relative risk reduction (RRR) ≥25% was calculated across assumed controlled risks (ACR) ranging from 0.01 to 0.99. Statistically significant improvements were found for pain (ES, -0.75, 95% CI, -0.99, -0.51; Q = 8.9, p = 0.26; I2 = 21%), stiffness (ES, -0.70, 95% CI, -0.95, -0.46; Q = 9.6, p = 0.21; I2 = 27%), and physical function (ES, -0.91, 95% CI, -1.12, -0.70; Q = 7.2, p = 0.40; I2 = 3%). The intersection of results for a NNT ≤10 and RRR ≥25% yielded high evidence and clinically relevant improvements across a wide range of ACR for pain (0.15 to 0.88), stiffness (0.15 to 0.87), and physical function (0.13 to 0.97). These findings suggest that Tai Chi results in statistically significant as well as clinically important improvements in pain, stiffness, and physical function across a wide range of ACR in adults with KOA.

Walking and resting blood pressure: An inter-individual response difference meta-analysis of randomized controlled trials

While walking is associated with reductions in resting SBP and DBP, a lack of true IIRD exists, suggesting that factors other than training response variation (random variation, physiological responses associated with behavioral changes that are not the result of walking) are responsible for the observed variation in resting SBP and DBP.

Systematic Review and Meta-Analysis: Clinical, Endoscopic, Histological and Safety Placebo Rates in Induction and Maintenance Trials of Ulcerative Colitis

BACKGROUND AND AIMS

Quantifying placebo rates and the factors influencing them are essential to inform trial design. We provide a contemporary summary of clinical, endoscopic, histological and safety placebo rates in induction and maintenance clinical trials of ulcerative colitis, and identify factors influencing them.

METHODS

MEDLINE, EMBASE and the Cochrane library were searched from April 2014 to April 2020, updating a prior meta-analysis that searched from inception to April 2014. We included placebo-controlled trials of aminosalicylates, corticosteroids, immunosuppressives, small-molecules and biologics in adults with ulcerative colitis. Placebo rates were pooled using random-effects and mixed-effects meta-regression models to assess the associated study-level.

RESULTS

In 119 trials [92 induction, 27 maintenance] clinical, endoscopic and histological remission placebo rates for induction trials were 11% (95% confidence interval [CI] 9-13%), 19% [95% CI 15-23%] and 15% [95% CI 11-19%], respectively; for maintenance trials, clinical and endoscopic placebo remission rates were 18% [95% CI 12-25%] and 20% [95% CI 15-25%], respectively. Higher endoscopic subscore and a higher rate of exposure to prior biologic therapy at enrolment were associated with lower clinical and endoscopic placebo remission rates. Absence of central reading was associated with an increase in placebo endoscopic response and remission rates. More follow-up visits and increasing trial duration were associated with higher clinical placebo rates.

CONCLUSIONS

Placebo rates in ulcerative colitis trials vary according to the endpoint assessed, whether it is for assessment of response or remission, and whether the trial is designed for induction or maintenance. These contemporary rates across different endpoints and drug classes will help to inform trial design.

An updated systematic review and meta-analysis of the effect of statins on asymmetric dimethylarginine

OBJECTIVES

We conducted an updated systematic review and meta-analysis of the effect of statins on serum or plasma concentrations of the endogenous inhibitor of endothelial nitric oxide synthase, asymmetric N^G,N^G-dimethyl-l-arginine (ADMA).

METHODS

A systematic literature search was conducted in the electronic databases PubMed, Web of Science, and Scopus, from inception to July 2021. Risk of bias and certainty of evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for analytical studies and GRADE, respectively.

RESULTS

In 23 studies, reporting 25 treatment arms in 845 participants (mean age 53 years, 57% males, treatment duration 4-48 weeks), statins significantly reduced ADMA concentrations (SMD = -0.39, 95% CI -0.62 to -0.16, p = 0.001; moderate certainty of evidence). The extreme heterogeneity observed was substantially reduced in study subgroups of specific class and individual statins, regional areas, and analytical methods for ADMA concentrations. There was no publication bias. In sensitivity analysis, the corresponding SMD values were not substantially modified when individual studies were sequentially removed. Significant associations were observed, in meta-regression, between the SMD and publication year (t = -3.25, p = 0.003), but not baseline cholesterol concentrations.

CONCLUSION

Statin treatment significantly lowers ADMA concentrations. This effect is independent of baseline cholesterol. Prospective studies are required to determine whether ADMA-lowering mediates, at least partly, the protective effects of statins against atherosclerotic cardiovascular disease. (PROSPERO registration number: CRD42021275123).

School-based interventions for the treatment of childhood obesity: a systematic review, meta-analysis and meta-regression of cluster randomised controlled trials

OBJECTIVE

Schools offer an ideal setting for childhood obesity interventions due to their access to children and adolescents. This review aimed to systematically review the impact of school-based intervention for the treatment of childhood obesity.

DESIGN

Eight databases were searched from inception till 30 May 2020. A revised Cochrane risk-of-bias tool and the Grading of Recommendations, Assessment, Development and Evaluations criteria were used to evaluate the risk of bias and overall evidence. Meta-analysis and meta-regression were performed on Stata software using the random effects model. Overall effect was evaluated using Hedges' g, and heterogeneity was assessed using Cochran's Q and I2.

SETTING

Cluster randomised controlled trials (cluster-RCT) delivered in school.

PARTICIPANTS

Children and adolescents (6-18 years of age) with overweight and obesity.

RESULTS

Twelve cluster-RCT from seven countries with 1755 participants were included in the meta-analysis. School-based interventions for the treatment of childhood obesity reduced BMI and BMI z-scores with a medium effect (g = 0·52). Subgroup analyses showed greater effectiveness of brief school-based interventions and the interventions conducted in lower-middle to upper-middle economies. Meta-regression assessed the heterogeneity and the final model, with covariates of the type of economies and trial duration, accounted for 41·2 % of the variability. The overall quality of evidence was rated low because of the high risk of bias and inconsistency.

CONCLUSIONS

School-based interventions are a possible approach to provide universal healthcare for the treatment of childhood obesity, and further well-designed cluster-RCT with longer follow-up are needed. This study is registered with PROSPERO (CRD42020160735).

Isometric exercise and inter-individual response differences on resting systolic and diastolic blood pressure in adults: a meta-analysis of randomized controlled trials

PURPOSE

Isometric exercise (IE) has been shown to reduce resting systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults. However, no one to date has determined whether true inter-individual response differences (IIRD) versus random variability exist with respect to IE and resting SBP and DBP in adults ≥18 years of age. The purpose of the current study was to address this gap.

METHODS AND MATERIALS

Using the meta-analytic approach, randomised controlled trials from a recent meta-analysis that examined the effects of IE on resting SBP and DBP were included. Change outcome standard deviations for SBP and DBP from IE and control groups were used to calculate true IIRD from each study. The inverse variance heterogeneity (IVhet) model was used to pool results.

RESULTS

Pooled changes for true IIRD in SBP (16 studies, 411 participants) were 3.3 mmHg (95% confidence interval, -3.1 to 5.6 mmHg) while tau (τ) was 4.2. For DBP, true IIRD (16 studies, 411 participants) were 2.3 mmHg (95% confidence interval, -0.7 to 3.3 mmHg) while tau (τ) was 2.2. The 95% prediction interval for true IIRD in a future study was -5.8 to 7.4 mmHg for SBP and -2.7 to 4.2 mmHg for DBP. The percent chance, i.e. probability, of a clinically meaningful difference of 2 mmHg was 68% for SBP and 75% for DBP, both of which were only considered as 'possibly clinically important'.

CONCLUSION

While IE reduces resting SBP and DBP in adults, the results of the current study suggest that random variability versus true IIRD account for any potential differences as a result of IE on changes in resting SBP and DBP in adults. Thus, a search for potential moderators and mediators, including potential genetic interactions associated with IE, may not be warranted.

Interventions to improve physical activity in colorectal cancer survivors: protocol for a systematic review and meta-analysis of randomized controlled trials

AIM

To examine the effectiveness of physical activity (PA) interventions on changes in PA among colorectal cancer survivors, including an examination of theoretical versus atheoretical-driven approaches, with a special focus on their effectiveness across ethnic and racial minorities.

DESIGN

Systematic review with aggregated data meta-analyses.

DATA SOURCES

Using six databases (Cochrane Central Register of Controlled Trials, PubMed, PsycINFO, CINAHL with full text, Scopus and Web of Science), we will screen for randomized controlled trials written in English from May 1, 1993 up to December 31, 2020.

REVIEW METHODS

Dual study-selection and data abstraction will be performed. The Behavior Change Technique Taxonomy (v1) will be used to examine behavior change techniques among selected studies, while the Theory Coding Scheme will be used to assess the extent of theory use. Risk of bias will be assessed using the revised Cochrane risk-of-bias tool for randomized trials, while the strength of the evidence will be assessed using the Grading of Recommendations Assessment, Development, and Evaluation instrument. In addition, intervention delivery will be appraised using the Template for Intervention Description and Replication. Changes in PA from each study will be calculated using the standardized mean difference effect size (Hedge's g). Results will be pooled using the inverse-variance heterogeneity model. Heterogeneity (Cochran's Q) and inconsistency (I² ) will be examined, while small-study effects (publication bias) will be evaluated using the Doi plot and LFK Index. Meta-regression will also be conducted to examine for potential associations between changes in physical activity and selected covariates (theoretical versus atheoretical-driven approaches, race/ethnicity).

DISCUSSION

This systematic review will identify specific racial/ethnic minorities for whom interventions are most effective and summarize the evidence of the effectiveness of theoretical vs. theoretical based intervention.

IMPACT

This systematic review can direct policymakers and practitioners towards actions that are likely to bring about positive physical activity behaviour change.

Yoga, Health-Related Quality of Life and Mental Well-Being: A Re-analysis of a Meta-analysis Using the Quality Effects Model

BACKGROUND

Provide robust and practically relevant information regarding the association between yoga, health-related quality-of-life (HRQOL), and mental well-being (MWB) in older adults.

METHODS

Data were derived from a recent meta-analysis of 12 randomized controlled yoga trials representing 752 adults ≥60 years of age. Standardized mean difference effect sizes (ESs) were pooled using the recently developed quality effects model and 95% compatibility intervals (CI). Small-study effects were examined using the Doi plot and Luis Furuya-Kanamori (LFK) index. Sensitivity and cumulative meta-analyses were conducted as well as percentile improvement, number needed to treat (NNT), and number to benefit. The grading of recommendations assessment, development, and evaluation (GRADE) instrument was used to assess the strength of the evidence.

RESULTS

Yoga was associated with improvements in both HRQOL (ES = 0.51, 95% CI, 0.25-0.77, I2 = 63.1%) and MWB (ES = 0.39, 95% CI, 0.15-0.63, I2 =56.2%). Percentile improvements were 19.5 for HRQOL and 15.3 for MWB whereas the NNT was 4 for HRQOL and 5 for MWB. An estimated 378,222 and 302,578 U.S. yoga-practicing adults ≥65 years of age could potentially improve their HRQOL and MWB, respectively. Major asymmetry suggestive of small-study effects was observed for MWB but not HRQOL. Further examination for asymmetry revealed that greater improvements in MWB were associated with more (151 vs. 68) minutes of yoga per week (p = .007). Overall strength of evidence was considered "high" for HRQOL and "moderate" for MWB.

CONCLUSIONS

Yoga is associated with improvements in HRQOL and MWB among older adults, with approximately 150 minutes or more per week possibly optimal.

Supporter Profiling in Recycled Water Reuse: Evidence from Meta-Analysis

Recycled water is considered as a viable alternative water source, and its use is of great significance in dealing with the shortage of water resources. However, it is often rejected by the public during its promotion. To identity the common social attributes of proponents of recycled water, it is essential to study the profiled customers’ willingness to accept recycled water during the most difficult initial stage of promoting recycled water use projects. A meta-analysis was conducted in this study to deal with data concerning the influence of different social demographic factors on the public’s acceptance of recycled water use. Three steps of meta-analysis were mainly used in this paper. First, a random-effect model was used to measure the effect size of influencing factors, such as age, gender, and education. It was found that younger women were more likely to accept recycled water use than older men, and individuals with higher education were more willing to accept recycled water. Then, a cumulative meta-analysis showed that it was feasible to select young women with higher education as target profile customers in the initial stage of recycled water promotion. Finally, according to a meta-regression analysis, it was revealed that different research areas and selected model methods have important regulatory effects on the intention of the target population to use recycled water.

Evidence-Based Research Series-Paper 2 : Using an Evidence-Based Research approach before a new study is conducted to ensure value

BACKGROUND AND OBJECTIVES

There is considerable actual and potential waste in research. The aim of this article is to describe how using an evidence-based research approach before conducting a study helps to ensure that the new study truly adds value.

STUDY DESIGN AND SETTING

Evidence-based research is the use of prior research in a systematic and transparent way to inform a new study so that it is answering questions that matter in a valid, efficient, and accessible manner. In this second article of the evidence-based research series, we describe how to apply an evidence-based research approach before starting a new study.

RESULTS

Before a new study is performed, researchers need to provide a solid justification for it using the available scientific knowledge as well as the perspectives of end users. The key method for both is to conduct a systematic review of earlier relevant studies.

CONCLUSION

Describing the ideal process illuminates the challenges and opportunities offered through the suggested evidence-based research approach. A systematic and transparent approach is needed to provide justification for and to optimally design a relevant and necessary new study.

Heparin-bonded versus standard polytetrafluoroethylene arteriovenous grafts: A Bayesian perspective on a randomized controlled trial for comparative effectiveness

BACKGROUND

Heparin-bonded polytetrafluoroethylene grafts were marketed to improve hemodialysis access outcomes but are twice the cost of standard polytetrafluoroethylene. We launched a randomized trial of heparin-bonded polytetrafluoroethylene versus standard polytetrafluoroethylene for hemodialysis access to compare patency. Since the trial began, additional studies were published with heterogeneous findings. We performed an interim analysis by Bayesian methods using prior probability from meta-analysis of existing literature.

METHODS

NCT01601873 is a randomized, blinded trial of heparin-bonded polytetrafluoroethylene versus standard polytetrafluoroethylene for dialysis access at 5 sites. Planned sample size was 200 with 1-year primary patency as the primary endpoint. At interim analysis (50% of sample size at 1 year), we also performed a meta-analysis for 1-year primary patency with a random effects model to compute summary rate ratio and standard-error estimates. Meta-analysis estimates formed a prior probability for a Bayesian Cox regression model, and trial data were reanalyzed to develop posterior probability of heparin-bonded polytetrafluoroethylene effectiveness at our hypothesized effect size. Futility analysis was conducted using posterior probability estimates.

RESULTS

One hundred and five patients were enrolled at the time of interim analysis. One-year primary patency was 34.9% in the heparin-bonded-polytetrafluoroethylene group vs 32.7% in the standard-polytetrafluoroethylene group (P = .884). Summary rate ratio from the meta-analysis (1,209 patients) was 0.87 favoring heparin-bonded polytetrafluoroethylene (P = .33). Posterior hazard ratio from Cox regression was 0.90 (credible interval 0.70-1.13) favoring heparin-bonded polytetrafluoroethylene, which was not significant. Bayesian posterior probability of the a priori hypothesized 20% better patency with heparin-bonded polytetrafluoroethylene was 24%. Sample size to detect superiority with the small observed effect size would require about 3,800 subjects.

CONCLUSION

Current evidence does not demonstrate sufficiently large benefit of heparin-bonded polytetrafluoroethylene over standard polytetrafluoroethylene for dialysis access to justify higher cost. Given similar 1-year patency rates, a conclusive finding of superiority was judged to be infeasible, and the trial was stopped for futility.

Psychological therapies for people with borderline personality disorder

BACKGROUND

Over the decades, a variety of psychological interventions for borderline personality disorder (BPD) have been developed. This review updates and replaces an earlier review (Stoffers-Winterling 2012).

OBJECTIVES

To assess the beneficial and harmful effects of psychological therapies for people with BPD.

SEARCH METHODS

In March 2019, we searched CENTRAL, MEDLINE, Embase, 14 other databases and four trials registers. We contacted researchers working in the field to ask for additional data from published and unpublished trials, and handsearched relevant journals. We did not restrict the search by year of publication, language or type of publication.

SELECTION CRITERIA

Randomised controlled trials comparing different psychotherapeutic interventions with treatment-as-usual (TAU; which included various kinds of psychotherapy), waiting list, no treatment or active treatments in samples of all ages, in any setting, with a formal diagnosis of BPD. The primary outcomes were BPD symptom severity, self-harm, suicide-related outcomes, and psychosocial functioning. There were 11 secondary outcomes, including individual BPD symptoms, as well as attrition and adverse effects.

DATA COLLECTION AND ANALYSIS

At least two review authors independently selected trials, extracted data, assessed risk of bias using Cochrane's 'Risk of bias' tool and assessed the certainty of the evidence using the GRADE approach. We performed data analysis using Review Manager 5 and quantified the statistical reliability of the data using Trial Sequential Analysis.

MAIN RESULTS

We included 75 randomised controlled trials (4507 participants), predominantly involving females with mean ages ranging from 14.8 to 45.7 years. More than 16 different kinds of psychotherapy were included, mostly dialectical behaviour therapy (DBT) and mentalisation-based treatment (MBT). The comparator interventions included treatment-as-usual (TAU), waiting list, and other active treatments. Treatment duration ranged from one to 36 months. Psychotherapy versus TAU Psychotherapy reduced BPD symptom severity, compared to TAU; standardised mean difference (SMD) -0.52, 95% confidence interval (CI) -0.70 to -0.33; 22 trials, 1244 participants; moderate-quality evidence. This corresponds to a mean difference (MD) of -3.6 (95% CI -4.4 to -2.08) on the Zanarini Rating Scale for BPD (range 0 to 36), a clinically relevant reduction in BPD symptom severity (minimal clinical relevant difference (MIREDIF) on this scale is -3.0 points). Psychotherapy may be more effective at reducing self-harm compared to TAU (SMD -0.32, 95% CI -0.49 to -0.14; 13 trials, 616 participants; low-quality evidence), corresponding to a MD of -0.82 (95% CI -1.25 to 0.35) on the Deliberate Self-Harm Inventory Scale (range 0 to 34). The MIREDIF of -1.25 points was not reached. Suicide-related outcomes improved compared to TAU (SMD -0.34, 95% CI -0.57 to -0.11; 13 trials, 666 participants; low-quality evidence), corresponding to a MD of -0.11 (95% CI -0.19 to -0.034) on the Suicidal Attempt Self Injury Interview. The MIREDIF of -0.17 points was not reached. Compared to TAU, psychotherapy may result in an improvement in psychosocial functioning (SMD -0.45, 95% CI -0.68 to -0.22; 22 trials, 1314 participants; low-quality evidence), corresponding to a MD of -2.8 (95% CI -4.25 to -1.38), on the Global Assessment of Functioning Scale (range 0 to 100). The MIREDIF of -4.0 points was not reached. Our additional Trial Sequential Analysis on all primary outcomes reaching significance found that the required information size was reached in all cases. A subgroup analysis comparing the different types of psychotherapy compared to TAU showed no clear evidence of a difference for BPD severity and psychosocial functioning. Psychotherapy may reduce depressive symptoms compared to TAU but the evidence is very uncertain (SMD -0.39, 95% CI -0.61 to -0.17; 22 trials, 1568 participants; very low-quality evidence), corresponding to a MD of -2.45 points on the Hamilton Depression Scale (range 0 to 50). The MIREDIF of -3.0 points was not reached. BPD-specific psychotherapy did not reduce attrition compared with TAU. Adverse effects were unclear due to too few data. Psychotherapy versus waiting list or no treatment Greater improvements in BPD symptom severity (SMD -0.49, 95% CI -0.93 to -0.05; 3 trials, 161 participants), psychosocial functioning (SMD -0.56, 95% CI -1.01 to -0.11; 5 trials, 219 participants), and depression (SMD -1.28, 95% CI -2.21 to -0.34, 6 trials, 239 participants) were observed in participants receiving psychotherapy versus waiting list or no treatment (all low-quality evidence). No evidence of a difference was found for self-harm and suicide-related outcomes. Individual treatment approaches DBT and MBT have the highest numbers of primary trials, with DBT as subject of one-third of all included trials, followed by MBT with seven RCTs. Compared to TAU, DBT was more effective at reducing BPD severity (SMD -0.60, 95% CI -1.05 to -0.14; 3 trials, 149 participants), self-harm (SMD -0.28, 95% CI -0.48 to -0.07; 7 trials, 376 participants) and improving psychosocial functioning (SMD -0.36, 95% CI -0.69 to -0.03; 6 trials, 225 participants). MBT appears to be more effective than TAU at reducing self-harm (RR 0.62, 95% CI 0.49 to 0.80; 3 trials, 252 participants), suicidality (RR 0.10, 95% CI 0.04, 0.30, 3 trials, 218 participants) and depression (SMD -0.58, 95% CI -1.22 to 0.05, 4 trials, 333 participants). All findings are based on low-quality evidence. For secondary outcomes see review text.

AUTHORS' CONCLUSIONS

Our assessments showed beneficial effects on all primary outcomes in favour of BPD-tailored psychotherapy compared with TAU. However, only the outcome of BPD severity reached the MIREDIF-defined cut-off for a clinically meaningful improvement. Subgroup analyses found no evidence of a difference in effect estimates between the different types of therapies (compared to TAU) . The pooled analysis of psychotherapy versus waiting list or no treatment found significant improvement on BPD severity, psychosocial functioning and depression at end of treatment, but these findings were based on low-quality evidence, and the true magnitude of these effects is uncertain. No clear evidence of difference was found for self-harm and suicide-related outcomes. However, compared to TAU, we observed effects in favour of DBT for BPD severity, self-harm and psychosocial functioning and, for MBT, on self-harm and suicidality at end of treatment, but these were all based on low-quality evidence. Therefore, we are unsure whether these effects would alter with the addition of more data.

Effect Declines Are Systematic, Strong, and Ubiquitous: A Meta-Meta-Analysis of the Decline Effect in Intelligence Research

Empirical sciences in general and psychological science in particular are plagued by replicability problems and biased published effect sizes. Although dissemination bias-related phenomena such as publication bias, time-lag bias, or visibility bias are well-known and have been intensively studied, another variant of effect distorting mechanisms, so-called decline effects, have not. Conceptually, decline effects are rooted in low initial (exploratory) study power due to strategic researcher behavior and can be expected to yield overproportional effect declines. Although decline effects have been documented in individual meta-analytic investigations, systematic evidence for decline effects in the psychological literature remains to date unavailable. Therefore, we present in this meta-meta-analysis a systematic investigation of the decline effect in intelligence research. In all, data from 22 meta-analyses comprising 36 meta-analytical and 1,391 primary effect sizes (N = 697,000+) that have been published in the journal Intelligence were included in our analyses. Two different analytic approaches showed consistent evidence for a higher prevalence of cross-temporal effect declines compared to effect increases, yielding a ratio of about 2:1. Moreover, effect declines were considerably stronger when referenced to the initial primary study within a meta-analysis, yielding about twice the magnitude of effect increases. Effect misestimations were more substantial when initial studies had smaller sample sizes and reported larger effects, thus indicating suboptimal initial study power as the main driver of effect misestimations in initial studies. Post hoc study power comparisons of initial versus subsequent studies were consistent with this interpretation, showing substantially lower initial study power of declining, than of increasing effects. Our findings add another facet to the ever accumulating evidence about non-trivial effect misestimations in the scientific literature. We therefore stress the necessity for more rigorous protocols when it comes to designing and conducting primary research as well as reporting findings in exploratory and replication studies. Increasing transparency in scientific processes such as data sharing, (exploratory) study preregistration, but also self- (or independent) replication preceding the publication of exploratory findings may be suitable approaches to strengthen the credibility of empirical research in general and psychological science in particular.

Contrasting evidence to reimbursement reality for off-label use (OLU) of drug treatments in cancer care: rationale and design of the CEIT-OLU project

Background

Off-label use (OLU) of a drug reflects a perceived unmet medical need, which is common in oncology. Cancer drugs are often highly expensive and their reimbursement is a challenge for many healthcare systems. OLU is frequently regulated by reimbursement restrictions. For evidence-based healthcare, treatment ought to be reimbursed if there is sufficient clinical evidence for treatment benefit independently of patient factors not related to the treatment indication. However, little is known about the reality of OLU reimbursement and its association with the underlying clinical evidence. Here, we aim to investigate the relationship of reimbursement decisions with the underlying clinical evidence.

Methods/ design

We will extract patient characteristics and details on treatment and reimbursement of cancer drugs from over 3000 patients treated in three Swiss hospitals. We will systematically search for clinical trial evidence on benefits associated with OLU in the most common indications. We will describe the prevalence of OLU in Switzerland and its reimbursement in cancer care, and use multivariable logistic regression techniques to investigate the association of approval/rejection of a reimbursement requests to the evidence on treatment effects and to further factors, including type of drug, molecular predictive markers and the health insurer.

Discussion

Our study will provide a systematic overview and assessment of OLU and its reimbursement reality in Switzerland. We may provide a better understanding of the access to cancer care that is regulated by health insurers and we hope to identify factors that determine the level of evidence-based cancer care in a highly diverse western healthcare system.

Ethnic inequalities in the incidence of diagnosis of severe mental illness in England: a systematic review and new meta-analyses for non-affective and affective psychoses

PURPOSE

Although excess risks particularly for a diagnosis of schizophrenia have been identified for ethnic minority people in England and other contexts, we sought to identify and synthesise up-to-date evidence (2018) for affective in addition to non-affective psychoses by specific ethnic groups in England.

METHODS

Systematic review and meta-analysis of ethnic differences in diagnosed incidence of psychoses in England, searching nine databases for reviews (citing relevant studies up to 2009) and an updated search in three databases for studies between 2010 and 2018. Studies from both searches were combined in meta-analyses allowing coverage of more specific ethnic groups than previously.

RESULTS

We included 28 primary studies. Relative to the majority population, significantly higher risks of diagnosed schizophrenia were found in Black African (Relative risk, RR 5.72, 95% CI 3.87-8.46, n = 9); Black Caribbean (RR 5.20, 95% CI 4.33-6.24, n = 21); South Asian (RR 2.27, 95% CI 1.63-3.16, n = 14); White Other (RR 2.24, 95% CI 1.59-3.14, n = 9); and Mixed Ethnicity people (RR 2.24, 95% CI 1.32-3.80, n = 4). Significantly higher risks for diagnosed affective psychoses were also revealed: Black African (RR 4.07, 95% CI 2.27-7.28, n = 5); Black Caribbean (RR 2.91, 95% CI 1.78-4.74, n = 16); South Asian (RR 1.71, 95% CI 1.07-2.72, n = 8); White Other (RR 1.55, 95% CI 1.32-1.83, n = 5); Mixed Ethnicity (RR 6.16, 95% CI 3.99-9.52, n = 4).

CONCLUSIONS

The risk for a diagnosis of non-affective and affective psychoses is particularly elevated for Black ethnic groups, but is higher for all ethnic minority groups including those previously not assessed through meta-analyses (White Other, Mixed Ethnicity). This calls for further research on broader disadvantages affecting ethnic minority people.

Treatment success rate among adult pulmonary tuberculosis patients in sub-Saharan Africa: a systematic review and meta-analysis

OBJECTIVES

To summarise treatment success rate (TSR) among adult bacteriologically confirmed pulmonary tuberculosis (BC-PTB) patients in sub-Saharan Africa (SSA).

DESIGN

We searched MEDLINE, EMBASE, Google Scholar and Web of Science electronic databases for eligible studies published in the decade between 1 July 2008 and 30 June 2018. Two independent reviewers extracted data and disagreements were resolved by consensus with a third reviewer. We used random-effects model to pool TSR in Stata V.15, and presented results in a forest plot with 95% CIs and predictive intervals. We assessed heterogeneity with Cochrane's (Q) test and quantified with I-squared values. We checked publication bias with funnel plots and Egger's test. We performed subgroup, meta-regression, sensitivity and cumulative meta-analyses.

SETTING

SSA.

PARTICIPANTS

Adults 15 years and older, new and retreatment BC-PTB patients.

OUTCOMES

TSR measured as the proportion of smear-positive TB cases registered under directly observed therapy in a given year that successfully completed treatment, either with bacteriologic evidence of success (cured) or without (treatment completed).

RESULTS

31 studies (2 cross-sectional, 1 case-control, 17 retrospective cohort, 6 prospective cohort and 5 randomised controlled trials) involving 18 194 participants were meta-analysed. 28 of the studies had good quality data. Egger's test indicated no publication bias, rather small study effect. The pooled TSR was 76.2% (95% CI 72.5% to 79.8%; 95% prediction interval, 50.0% to 90.0%, I² statistics=96.9%). No single study influenced the meta-analytical results or conclusions. Between 2008 and 2018, a gradual but steady decline in TSR occurred in SSA but without statistically significant time trend variation (p=0.444). The optimum TSR of 90% was not achieved.

CONCLUSION

Over the past decade, TSR was heterogeneous and suboptimal in SSA, suggesting context and country-specific strategies are needed to end the TB epidemic.

PROSPERO REGISTRATION NUMBER

CRD42018099151.

Multifactorial interventions for preventing falls in older people living in the community: a systematic review and meta-analysis of 41 trials and almost 20 000 participants

Objective

To assess the longer term effects of multifactorial interventions for preventing falls in older people living in the community, and to explore whether prespecific trial-level characteristics are associated with greater fall prevention effects.

Design

Systematic review with meta-analysis and meta-regression.

Data sources

MEDLINE, EMBASE, CINHAL, CENTRAL and trial registries were searched up to 25 July 2018.

Study selection

We included randomised controlled trials (≥12 months’ follow-up) evaluating the effects of multifactorial interventions on falls in older people aged 65 years and over, living in the community, compared with either usual care or usual care plus advice.

Review methods

Two authors independently verified studies for inclusion, assessed risk of bias and extracted data. Rate ratios (RaR) with 95% CIs were calculated for rate of falls, risk ratios (RR) for dichotomous outcomes and standardised mean difference for continuous outcomes. Data were pooled using a random effects model. The Grading of Recommendations, Assessment, Development and Evaluation was used to assess the quality of the evidence.

Results

We included 41 trials totalling 19 369 participants; mean age 72–85 years. Exercise was the most common prespecified component of the multifactorial interventions (85%; n=35/41). Most trials were judged at unclear or high risk of bias in ≥1 domain. Twenty trials provided data on rate of falls and showed multifactorial interventions may reduce the rate at which people fall compared with the comparator (RaR 0.79, 95% CI 0.70 to 0.88; 20 trials; 10 116 participants; I²=90%; low-quality evidence). Multifactorial interventions may also slightly lower the risk of people sustaining one or more falls (RR 0.95, 95% CI 0.90 to 1.00; 30 trials; 13 817 participants; I²=56%; moderate-quality evidence) and recurrent falls (RR 0.88, 95% CI 0.78 to 1.00; 15 trials; 7277 participants; I²=46%; moderate-quality evidence). However, there may be little or no difference in other fall-related outcomes, such as fall-related fractures, falls requiring hospital admission or medical attention and health-related quality of life. Very few trials (n=3) reported on adverse events related to the intervention. Prespecified subgroup analyses showed that the effect on rate of falls may be smaller when compared with usual care plus advice as opposed to usual care only. Overall, heterogeneity remained high and was not explained by the prespecified characteristics included in the meta-regression.

Conclusion

Multifactorial interventions (most of which include exercise prescription) may reduce the rate of falls and slightly reduce risk of older people sustaining one or more falls and recurrent falls (defined as two or more falls within a specified time period).

Trial registration number

CRD42018102549.

Leisure Time Physical Activity Reduces the Risk for Stroke in Adults: A Reanalysis of a Meta-Analysis Using the Inverse-Heterogeneity Model

Objective

Apply more robust and additional analyses to a previous meta-analysis that reported statistically significant associations between leisure time physical activity (LTPA) and stroke.

Methods

A reanalysis of a previous meta-analysis that included nine prospective cohort studies representing 269,594 men and women 25-84 years of age and in which the association between LTPA and incident stroke was examined. Follow-up periods ranged from 7.7 to 32.0 years. Relative risks (RR) from each study were pooled using the inverse-heterogeneity model. Heterogeneity was examined using the Q statistic, inconsistency using I², and small-study effects using Doi plots and the LFK index. Influence and cumulative meta-analysis were also conducted.

Results

Using low LTPA as the reference, moderate LTPA was associated with a statistically significant reduction in the risk for stroke in men (RR = 0.79, 95% CI = 0.65 to 0.95) and a trend in women (RR = 0.88, 95% CI = 0.78 to 1.0). High LTPA was associated with a statistically significant reduction in the risk for stroke in both men (RR = 0.72, 95% CI = 0.60 to 0.86) and women (RR = 0.78, 95% CI = 0.66 to 0.92). No statistically significant heterogeneity was observed and inconsistency was low. However, potential small-study effects were observed. With each study deleted once, results remained statistically significant. Cumulative meta-analysis demonstrated stability in results since at least 2005.

Conclusions

Leisure time physical activity is associated with a reduced risk of stroke in both men and women. However, the small-study effects observed suggest the possibility that results may be exaggerated.

Susceptibility to leishmaniasis is affected by host SLC11A1 gene polymorphisms: a systematic review and meta-analysis

Leishmaniases are cutaneous, mucocutaneous, and visceral diseases affecting humans and domesticated animals mostly in the tropical and subtropical areas of the planet. Host genetics have been widely investigated for their role in developing various infectious diseases. The SLC11A1 gene has been reported to play a role in neutrophil function and is associated with susceptibility to infectious and inflammatory diseases such as tuberculosis or rheumatoid arthritis. In the present meta-analysis, we investigate the genetic association of SLC11A1 polymorphisms with susceptibility to leishmaniasis. Genotypes and other risk-related data were collected from 13 case-control and family-based studies (after literature search). Conventional random-effects meta-analysis was performed using STATA 13. To pool case-control and family-based data, the weighted Stouffer's method was also applied. Eight polymorphisms were investigated: rs2276631, rs3731865, rs3731864, rs17221959, rs201565523, rs2279015, rs17235409, and rs17235416. We found that rs17235409 (D543N) and rs17235416 (1729 + 55del4) are significantly associated with a risk for cutaneous leishmaniasis (CL), whereas rs17221959, rs2279015, and rs17235409 are associated with visceral leishmaniasis (VL). Our results suggest that polymorphisms in SLC11A1 affect susceptibility to CL and VL. These findings open new pathways in understanding macrophage response to Leishmania infection and the genetic factors predisposing to symptomatic CL or VL that can lead to the usage of predictive biomarkers in populations at risk.

Social skills training for attention deficit hyperactivity disorder (ADHD) in children aged 5 to 18 years

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) in children is associated with hyperactivity and impulsivity, attention problems, and difficulties with social interactions. Pharmacological treatment may alleviate the symptoms of ADHD but this rarely solves difficulties with social interactions. Children with ADHD may benefit from interventions designed to improve their social skills. We examined the benefits and harms of social skills training on social skills, emotional competencies, general behaviour, ADHD symptoms, performance in school of children with ADHD, and adverse events.

OBJECTIVES

To assess the beneficial and harmful effects of social skills training in children and adolescents with ADHD.

SEARCH METHODS

In July 2018, we searched CENTRAL, MEDLINE, Embase, PsycINFO, 4 other databases and two trials registers.We also searched online conference abstracts, and contacted experts in the field for information about unpublished or ongoing randomised clinical trials. We did not limit our searches by language, year of publication, or type or status of publication, and we sought translation of the relevant sections of non-English language articles.

SELECTION CRITERIA

Randomised clinical trials investigating social skills training versus either no intervention or waiting-list control, with or without pharmacological treatment of both comparison groups of children and adolescents with ADHD.

DATA COLLECTION AND ANALYSIS

We conducted the review in accordance with the Cochrane Handbook for Systematic Reviews of Intervention. We performed the analyses using Review Manager 5 software and Trial Sequential Analysis. We assessed bias according to domains for systematic errors. We assessed the certainty of the evidence with the GRADE approach.

MAIN RESULTS

We included 25 randomised clinical trials described in 45 reports. The trials included a total of 2690 participants aged between five and 17 years. In 17 trials, participants were also diagnosed with various comorbidities.The social skills interventions were described as: 1) social skills training, 2) cognitive behavioural therapy, 3) multimodal behavioural/psychosocial therapy, 4) child life and attention skills treatment, 5) life skills training, 6) the "challenging horizon programme", 7) verbal self-instruction, 8) meta-cognitive training, 9) behavioural therapy, 10) behavioural and social skills treatment, and 11) psychosocial treatment. The control interventions were no intervention or waiting list.The duration of the interventions ranged from five weeks to two years. We considered the content of the social skills interventions to be comparable and based on a cognitive-behavioural model. Most of the trials compared child social skills training or parent training combined with medication versus medication alone. Some of the experimental interventions also included teacher consultations.More than half of the trials were at high risk of bias for generation of the allocation sequence and allocation concealment. No trial reported on blinding of participants and personnel. Most of the trials did not report on differences between groups in medication for comorbid disorders. We used all eligible trials in the meta-analyses, but downgraded the certainty of the evidence to low or very low.We found no clinically relevant treatment effect of social skills interventions on the primary outcome measures: teacher-rated social skills at end of treatment (standardised mean difference (SMD) 0.11, 95% confidence interval (CI) 0.00 to 0.22; 11 trials, 1271 participants; I2 = 0%; P = 0.05); teacher-rated emotional competencies at end of treatment (SMD -0.02, 95% CI -0.72 to 0.68; two trials, 129 participants; I2 = 74%; P = 0.96); or on teacher-rated general behaviour (SMD -0.06 (negative value better), 95% CI -0.19 to 0.06; eight trials, 1002 participants; I2 = 0%; P = 0.33). The effect on the primary outcome, teacher-rated social skills at end of treatment, corresponds to a MD of 1.22 points on the social skills rating system (SSRS) scale (95% CI 0.09 to 2.36). The minimal clinical relevant difference (10%) on the SSRS is 10.0 points (range 0 to 102 points on SSRS).We found evidence in favour of social skills training on teacher-rated core ADHD symptoms at end of treatment for all eligible trials (SMD -0.26, 95% CI -0.47 to -0.05; 14 trials, 1379 participants; I2= 69%; P = 0.02), but the finding is questionable due to lack of support from sensitivity analyses, high risk of bias, lack of clinical significance, high heterogeneity, and low certainty.The studies did not report any serious or non-serious adverse events.

AUTHORS' CONCLUSIONS

The review suggests that there is little evidence to support or refute social skills training for children and adolescents with ADHD. We may need more trials that are at low risk of bias and a sufficient number of participants to determine the efficacy of social skills training versus no training for ADHD. The evidence base regarding adolescents is especially weak.

A systematic review and meta-analysis of predictors of airway intervention in adult epiglottitis

OBJECTIVE

Epiglottitis is typically considered a pediatric disease; however, there is growing evidence that the incidence of adult epiglottitis has changed since the introduction of the Haemophilus influenzae vaccine. The literature is composed of multiple small series with differing findings. To date, there has been no attempt to collaborate evidence on predictors of airway intervention in this disease.

METHODS

The population of interest was adults with a diagnosis of epiglottitis. The primary outcome in this review was incidence of airway intervention. A comprehensive literature search was conducted of the MEDLINE and Embase databases, and a separate random-effects model meta-analysis was undertaken for all outcome data. Moderator tests for comparison between prevaccine and postvaccine estimates were made, and absolute risk difference (RD) and relative risk (RR) calculations were made for all predictors of airway intervention.

RESULTS

Thirty studies and a total of 10,148 patients were finally included for meta-analysis. A significant decrease in airway intervention was seen post vaccine introduction introduction from 18.8% to 10.9% (P = 0.01). The presence of an abscess (RD 0.27, P = 0.04; RR 2.45, P < 0.001), stridor (RD 0.64, P < 0.001; RR 7.15, P < 0.001), or a history of diabetes mellitus (RD 0.11, P = 0.02; RR 2.15, P = 0.01) were associated with need for airway intervention.

CONCLUSION

In the postvaccine era, clinicians should expect to have to secure airways in 10.9% of cases. The presence of an epiglottic abscess, stridor, or a history of diabetes mellitus are the most reliable clinical features associated with need for airway intervention.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:465-473, 2020.

A Systematic Review and Meta-Analysis of the Prevalence of Methamphetamine Abuse in Iranian High School Students

Background and Aim: Abuse of drugs such as methamphetamine is one of the most important problems in high-school children and adolescents according to the World Health Organization (WHO), which has mentioned it as a concerning event in the world. Therefore, the purpose of this study was to estimate the prevalence of methamphetamine abuse in Iranian students using the meta-analysis method on studies conducted in Iran.

Materials and Methods: To select the studies, a systematic search was performed on leading databases, including ISI web of science, PubMed, Scopus, Embase, PsycINFO and PROSPERO with no language limits from their inception to 31 Jan 2018. Furthermore, local databases, including SID, Magiran, and IRANDOC were searched systematically using both Persian and English languages from their inception to 31 Jan 2018.

Results: We found a total of 828 potentially relevant studies, of which 30 met our criteria, and 7 articles (7452 students, 3063 females and 4389 males) were included. The pooled prevalence of methamphetamine use in Iranian students was 0.016% (95% CI: 0.06-0.041, P=0.00). The heterogeneity was low (I² =44.41, d.f = 6), which shows that about 94.41 of the total observed variance was true variance between the studies.

Conclusion: Although the prevalence of methamphetamine in high-school students is lower than in other drugs, a growing pattern in Iranian high-school students in recent years is a serious warning to authorities and families. Increasing families and students’ knowledge about the harmful effects of this drug can be an effective approach to reducing its prevalence in young people, especially high-school students.

Plasma Levels of Free Fatty Acids in Women with Gestational Diabetes and Its Intrinsic and Extrinsic Determinants: Systematic Review and Meta-Analysis

BACKGROUND

Free fatty acids, also known as nonesterified fatty acids, are proinflammatory molecules that induce insulin resistance in nonpregnant individuals. Nevertheless, the concentration of these molecules has not been systematically addressed in pregnant women.

OBJECTIVE

This meta-analysis is aimed at evaluating the difference in free fatty acid plasma levels between women with gestational diabetes and healthy pregnant controls and their intrinsic and extrinsic determinants.

METHODS

We performed a systematic search to find relevant studies published in English and Spanish using PubMed, SCOPUS, and ISI Web of Knowledge. We included observational studies measuring the mean plasma levels of free fatty acids among gestational diabetes and healthy pregnant women, with at least ten subjects being analyzed in each group. The standardized mean difference (SMD) by random effects modeling was used. Heterogeneity was assessed using Cochran's Q, H, and I ² statistics.

RESULTS

Among the 290 identified studies, twelve were selected for analysis. A total of 2426 women were included, from which 21% were diagnosed as having gestational diabetes. There were significantly higher levels of free fatty acids among women with gestational diabetes (SMD: 0.86; 0.54-1.18; p < 0.001) when compared to healthy pregnant controls and between-study heterogeneity (I ² = 91%). The metaregression analysis showed that the gestational age at inclusion was the only cofactor influencing the mean levels of free fatty acids, indicating a trend towards lower plasma levels of free fatty acids later in gestation (estimate: -0.074; -0.143 to -0.004; p = 0.036). No significant publication bias was found nor a trend towards greater results in small studies.

CONCLUSIONS

Women with gestational diabetes have higher levels of free fatty acids when compared to healthy pregnant controls. More investigation is needed to assess the potential role of free fatty acids in the prediction of gestational diabetes earlier in pregnancy.

Protocol for systematic review and meta-analysis of treatment success rate among adult patients with tuberculosis in sub-Saharan Africa

INTRODUCTION

Tuberculosis (TB) is a leading cause of mortality globally. Despite being curable, treatment success rates (TSRs) among adult patients with bacteriologically confirmed pulmonary TB (BC-PTB) in sub-Saharan Africa (SSA) differ considerably. This protocol documents and presents an explicit plan of a systematic review and meta-analysis to summarise TSR among adult patients with BC-PTB in SSA.

METHODS AND ANALYSIS

Two reviewers will search and extract data from MEDLINE, EMBASE, Ovid, Cumulative Index to Nursing and Allied Health Literature and Web of Science electronic databases. Observational and interventional studies published between 1 July 2008 and 30 June 2018, involving adult patients with BC-PTB will be eligible. Data abstraction disagreements will be resolved by consensus with a third reviewer, while percentage agreement computed with kappa statistics. TSR will be computed with Metaprop, a Stata command for pooling proportions using DerSimonian and Laird random effects model and presented in a forest plot with corresponding 95% CIs. Heterogeneity between included studies will be assessed with Cochran's Q test and quantified with I-squared values. Publication bias will be evaluated with funnel plots and tested with Egger's weighted regression. Time trends in TSR will be calculated with cumulative meta-analysis.

ETHICS AND DISSEMINATION

No ethical approval will be needed because data from previous published studies in which informed consent was obtained by primary investigators will be retrieved and analysed. We will prepare a manuscript for publication in a peer-reviewed journal and present the results at conferences.

PROSPERO REGISTRATION NUMBER

CRD42018099151.