Network Meta-Analysis Techniques for Synthesizing Prevention Science Evidence.

Network meta-analysis is a popular statistical technique for synthesizing evidence from studies comparing multiple interventions. Benefits of network meta-analysis, over more traditional pairwise meta-analysis approaches, include evaluating efficacy/safety of interventions within a single framework, increased precision, comparing pairs of interventions that have never been directly compared in a trial, and providing a hierarchy of interventions in terms of their effectiveness. Network meta-analysis is relatively underutilized in prevention science. This paper therefore presents a primer of network meta-analysis for prevention scientists who wish to apply this method or to critically appraise evidence from publications using the method. We introduce the key concepts and assumptions of network meta-analysis, namely, transitivity and consistency, and demonstrate their applicability to the field of prevention science. We then illustrate the method using a network meta-analysis examining the comparative effectiveness of brief alcohol interventions for preventing hazardous drinking among college students. We provide data and code for all examples. Finally, we discuss considerations that are particularly relevant in network meta-analyses in the field of prevention, such as including non-randomized evidence.

Early Optimistic Effect in Periodontology and Implant Dentistry Trials.

Differences in effect estimates between early primary trials included in a meta-analysis and the pooled estimate of meta-analysis might indicate potential novelty bias. The objective of this study was to assess the presence of novelty bias in a sample of studies published in periodontology and implant dentistry. On August 7, 2020, we searched the PubMed database for meta-analyses of clinical studies published between August 2015 and August 2020. Meta-analyses with at least 4 primary studies were selected for assessment. We fitted logistic regression models using trial characteristics as predictors to assess the association between these characteristics and 1) the odds of the first trial's estimate to be included in the meta-analysis confidence interval (CI) and 2) the odds of overlap between the first trial's CI and the meta-analysis prediction interval (PI). Ninety-two meta-analyses provided data for assessment. In absolute values, 70% of the meta-analyses have a pooled estimate smaller than the corresponding estimate of the first trial, although there was overlap of the CI of estimates from the first trial and the meta-analysis in 87% of the cases. This is probably due to the small number of trials in most meta-analyses and the subsequently large uncertainty associated with the pooled effect estimate. As the number of trials in the meta-analysis increased, the odds of the treatment effect estimate of the first trial to be included in the meta-analysis CI decreased by 15% for every additional trial (odds ratio, 0.85; 95% CI, 0.73 to 0.96). Meta-analytic effect estimates appear to be more conservative than those from the first trial in the meta-analysis. Our findings show evidence of novelty bias in periodontology and implant dentistry; therefore, clinicians should be aware of the risk of making decisions based on the information reported in new trials because of the risk of exaggerated estimates in these trials.

Illness perceptions and quality of life in families with child with atopic dermatitis.

OBJECTIVE: To assess the Quality of Life (QoL) of children with Atopic Dermatitis (AD) and their families and the impact of the mothers' illness perceptions on the family QoL. MATERIALS AND METHODS: Seventy-five children with AD (54 infants and 21 children) and their mothers participated in the study. The following questionnaires were administrated: 1. Brief Illness Perception Questionnaire (Brief IPQ); 2. Infant's Dermatitis Quality of Life Index (IDQOL); 3. Children's Dermatology Life Quality Index (CDLQI); 4. Dermatitis Family Impact Questionnaire (DFIQ) and 5. The Severity Scoring of Atopic Dermatitis (SCORAD). RESULTS: Atopic dermatitis had a moderate impact on the QoL of the infants (6.67±5.30), children (7.86±7.19) and their families (9.42±7.03). The DFIQ was associated with certain dimensions of the Brief IPQ, specifically, with Illness Identity (greater symptom burden) (r=0.615, p=0.000), beliefs about the Consequences of the illness (r=0.542, p=0.000), the Concerns (r=0.421, p=0.000) and the Emotional Representations (r=0.510, p=0.000). Correlation was demonstrated between IDQOL and DFIQ (r=0.662, p=0.000) and between CDLQI and DFIQ (r=0.832, p=0.000), and a weaker correlation between SCORAD and DFIQ (r=0.255, p=0.035). The chronicity of the AD showed negative association with DFIQ (p<0.001). CONCLUSIONS: The QoL of families with a child with AD is associated with the mother's illness perceptions about AD, the children's QoL and with both the severity and the chronicity of the disease. Therefore, clinicians should pay attention not only to the clinical characteristics of the children, but also to the parents' beliefs and emotions, to improve the family QoL.

Factor analysis and normative scores of Alcohol Use Disorders Identification Test (AUDIT) in a representative sample of the general population of Greece.

The most widely used screening instrument for alcohol use disorders (AUD) is the Alcohol Use Disorders Identification Test (AUDIT) which, although initially developed for use in primary care, is increasingly used in general population studies. Previous studies that have assessed the screening properties and the factorial structure of AUDIT were mostly based on clinical samples and did not take into consideration the possible differences in AUDIT factorial properties between subgroups according to age, sex and mental health status. Aim of the current study was to explore the distribution of AUDIT and AUDIT-Consumption (AUDIT-C) scores and the factorial structure of AUDIT in subgroups of participants according to sex, age and the presence of mental health disorder. Descriptive statistics and Exploratory/Confirmatory Factor Analysis of AUDIT were extracted in a general population representative sample of 4,894 Greek participants. Different cut-offs are suggested in order to screen 10% of the population with the highest severity of AUD into the aforementioned subgroups. Generally, a cut-off between 10-12 at AUDIT score is suggested for screening the 10% with the highest severity of alcohol use problems in subgroups of frequent alcohol consumers (e.g. younger males) and a cut-off between 4-5 would screen the 5% with the highest severity of alcohol use problems in subgroups of low alcohol-consumers (e.g. older women). A cut-off of 3 in AUDIT-C score is suggested for screening 25% of individuals with the heaviest alcohol consumption. The traditional three-factor model does not explain better the factorial structure of AUDIT compared to the 2-factors model. The AUDIT is a reliable instrument for assessing AUD and heavy alcohol consumption in the Greek general population. Age, sex and the presence of mental health disorders should be taken into consideration when selecting cut-offs for screening purposes in non-clinical samples.

Surgical treatment for hydrosalpinx prior to in-vitro fertilization embryo transfer: a network meta-analysis.

OBJECTIVE: The presence of hydrosalpinx impairs the outcome of in-vitro fertilization embryo transfer (IVF-ET). Surgical methods to either aspirate the fluid or isolate the affected Fallopian tubes have been attempted as a means of improving outcome. The aim of this network meta-analysis was to compare the effectiveness of surgical treatments for hydrosalpinx before IVF-ET. METHODS: An electronic search of MEDLINE, Scopus, Cochrane Central Register of Controlled Trials (Central) and the US Registry of clinical trials for articles published from inception to July 2015 was performed. Eligibility criteria included randomized controlled trials of women with hydrosalpinx before IVF-ET comparing ultrasound-guided aspiration of the fluid, tubal occlusion, salpingectomy or no intervention. Ongoing pregnancy was the primary outcome and clinical pregnancy, ectopic pregnancy and miscarriage were secondary outcomes. A random-effects network meta-analysis synthesizing direct and indirect evidence from the included trials was carried out. We estimated the relative effect sizes as risk ratios (RRs) and obtained the relative ranking of the interventions using cumulative ranking curves. The quality of evidence according to GRADE guidelines, adapted for network meta-analysis, was assessed. RESULTS: Proximal tubal occlusion (RR, 3.22 (95% CI, 1.27-8.14)) and salpingectomy (RR, 2.24 (95% CI, 1.27-3.95)) for treatment of hydrosalpinx were superior to no intervention for ongoing pregnancy. For an outcome of clinical pregnancy, all three interventions appeared to be superior to no intervention. No superiority could be ascertained between the three surgical methods for any of the outcomes. In terms of relative ranking, tubal occlusion was the best surgical treatment followed by salpingectomy for ongoing and clinical pregnancy rates. No significant statistical inconsistency was detected; however, the point estimates for some inconsistency factors and their CIs were relatively large. The small study number and sizes were the main limitations. The quality of evidence was commonly low/very low, especially when aspiration was involved, indicating that the results were not conclusive and should be interpreted with caution. CONCLUSIONS: Proximal tubal occlusion, salpingectomy and aspiration for treatment of hydrosalpinx scored consistently better than did no intervention for the outcome of IVF-ET. In terms of relative ranking, proximal tubal occlusion appeared to be the most effective intervention, followed by salpingectomy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.