OBJECTIVES: To systematically summarize the risk relationship between different levels of alcohol consumption and incidence of liver cirrhosis. METHODS: MEDLINE and Embase were searched up to March 6, 2019, to identify case–control and cohort studies with sex-specific results and more than 2 categories of drinking in relation to the incidence of liver cirrhosis. Study characteristics were extracted and random-effects meta-analyses and meta-regressions were conducted. RESULTS: A total of 7 cohort studies and 2 case–control studies met the inclusion criteria, providing data from 2,629,272 participants with 5,505 cases of liver cirrhosis. There was no increased risk for occasional drinkers. Consumption of one drink per day in comparison to long-term abstainers showed an increased risk for liver cirrhosis in women, but not in men. The risk for women was consistently higher compared to men. Drinking ≥5 drinks per day was associated with a substantially increased risk in both women (relative risk [RR] = 12.44, 95% confidence interval [CI]: 6.65–23.27 for 5–6 drinks, and RR = 24.58, 95% CI: 14.77–40.90 for ≥7 drinks) and men (RR = 3.80, 95% CI: 0.85–17.02, and RR = 6.93, 95% CI: 1.07–44.99, respectively). Heterogeneity across studies indicated an additional impact of other risk factors. DISCUSSION: Alcohol is a major risk factor for liver cirrhosis with risk increasing exponentially. Women may be at higher risk compared to men even with little alcohol consumption. More high-quality research is necessary to elucidate the role of other risk factors, such as genetic vulnerability, body weight, metabolic risk factors, and drinking patterns over the life course. High alcohol consumption should be avoided, and people drinking at high levels should receive interventions to reduce their intake.

Objective: To assess the characteristics and core statistical methodology specific to network meta-analyses (NMAs) in clinical research articles. Study Design and What is new?Key findings Although the amount of evidence (the number of treatments and studies) included in published NMAs remains stable, the undertaking and reporting of statistical methods have significantly improved over the years. The assumptions underlying NMA are increasingly discussed and evaluated using appropriate methods. Less than 10% of NMAs published in 2014 and 2015 failed to evaluate the assumptions of the joint synthesis. What this adds to what is knownThis meta-epidemiological study presents the largest collection of published NMAs over the past 16 years. It provides an overview of the structural characteristics and statistical methodology of 456 published networks of interventions. It shows that the statistical methods in NMA have considerably improved in all aspects and some, such as the use of appropriate methods to evaluate the plausibility of the assumptions, are now routinely performed. We conclude that the increasingly populous community of NMA methodologists is quickly advancing through the learning curve of statistical methods employed in NMA. What is the implication, what should change nowThe updated description of the structural characteristics of the published NMAs can be used to inform pragmatic simulations studies and the development of methods that are relevant to the type of networks typically found in the medical literature. Future tutorials and training should be focused on improving the methodology and reporting on items that, although they have improved, their prevalence remains low, such as the formal exploration of heterogeneity and inconsistency and the presentation of all pairwise treatment effects.

ObjectivesTo examine whether the association between emotional support and indicators of health and quality of life differs between Canadian and Latin American older adults.DesignCross-sectional analysis of the International Mobility in Aging Study (IMIAS). Social support from friends, family members, children and partner was measured with a previously validated social network and support scale (IMIAS-SNSS). Low social support was defined as ranking in the lowest site-specific quartile. Prevalence ratios (PR) of good health, depression and good quality of life were estimated with Poisson regression models, adjusting for age, gender, education, income and disability in activities of daily living.SettingKingston and Saint-Hyacinthe in Canada, Manizales in Colombia and Natal in Brazil.Participants1600 community-dwelling adults aged 65–74 years, n=400 at each site.Outcome measuresLikert scale question on self-rated health, Center for Epidemiological Studies Depression Scale and 10-point analogical quality-of-life (QoL) scale.ResultsRelationships between social support and study outcomes differed between Canadian and Latin American older adults. Among Canadians, those without a partner had a lower prevalence of good health (PR=0.90; 95% CI 0.82 to 0.98), and those with high support from friends had a higher prevalence of good health (PR=1.09; 95% CI 1.01 to 1.18). Among Latin Americans, depression was lower among those with high levels of support from family (PR=0.63; 95% CI 0.48 to 0.83), children (PR=0.60; 95% CI 0.45 to 0.80) and partner (PR=0.57; 95% CI 0.31 to 0.77); good QoL was associated with high levels of support from children (PR=1.54; 95% CI 1.20 to 1.99) and partner (PR=1.31; 95% CI 1.03 to 1.67).ConclusionsAmong older adults, different sources of support were relevant to health across societies. Support from friends and having a partner were related to good health in Canada, whereas in Latin America, support from family, children and partner were associated with less depression and better QoL.

BackgroundAlthough it is well established that heavy alcohol consumption increases the risk of hypertension, the risk associated with low levels of alcohol intake in men and women is unclear.Methods and ResultsWe searched Medline and Embase for original cohort studies on the association between average alcohol consumption and incidence of hypertension in people without hypertension. Random‐effects meta‐analyses and metaregressions were conducted. Data from 20 articles with 361 254 participants (125 907 men and 235 347 women) and 90 160 incident cases of hypertension (32 426 men and 57 734 women) were included. In people drinking 1 to 2 drinks/day (12 g of pure ethanol per drink), incidence of hypertension differed between men and women (relative riskwomen vs men=0.79; 95% confidence interval, 0.67–0.93). In men, the risk for hypertension in comparison with abstainers was relative risk=1.19 (1.07–1.31; I2=59%), 1.51 (1.30–1.76), and 1.74 (1.35–2.24) for consumption of 1 to 2, 3 to 4, and 5 or more standard drinks per day, respectively. In women, there was no increased risk for 1 to 2 drinks/day (relative risk=0.94; 0.88–1.01; I2=73%), and an increased risk for consumption beyond this level (relative risk=1.42; 1.22–1.66).ConclusionsAny alcohol consumption was associated with an increase in the risk for hypertension in men. In women, there was no risk increase for consumption of 1 to 2 drinks/day and an increased risk for higher consumption levels. We did not find evidence for a protective effect of alcohol consumption in women, contrary to earlier meta‐analyses.

BackgroundNetwork meta-analysis (NMA) has become a popular method to compare more than two treatments. This scoping review aimed to explore the characteristics and methodological quality of knowledge synthesis approaches underlying the NMA process. We also aimed to assess the statistical methods applied using the Analysis subdomain of the ISPOR checklist.MethodsComprehensive literature searches were conducted in MEDLINE, PubMed, EMBASE, and Cochrane Database of Systematic Reviews from inception until April 14, 2015. References of relevant reviews were scanned. Eligible studies compared at least four different interventions from randomised controlled trials with an appropriate NMA approach. Two reviewers independently performed study selection and data abstraction of included articles. All discrepancies between reviewers were resolved by a third reviewer. Data analysis involved quantitative (frequencies) and qualitative (content analysis) methods. Quality was evaluated using the AMSTAR tool for the conduct of knowledge synthesis and the ISPOR tool for statistical analysis.ResultsAfter screening 3538 citations and 877 full-text papers, 456 NMAs were included. These were published between 1997 and 2015, with 95% published after 2006. Most were conducted in Europe (51%) or North America (31%), and approximately one-third reported public sources of funding. Overall, 84% searched two or more electronic databases, 62% searched for grey literature, 58% performed duplicate study selection and data abstraction (independently), and 62% assessed risk of bias. Seventy-eight (17%) NMAs relied on previously conducted systematic reviews to obtain studies for inclusion in their NMA. Based on the AMSTAR tool, almost half of the NMAs incorporated quality appraisal results to formulate conclusions, 36% assessed publication bias, and 16% reported the source of funding. Based on the ISPOR tool, half of the NMAs did not report if an assessment for consistency was conducted or whether they accounted for inconsistency when present. Only 13% reported heterogeneity assumptions for the random-effects model.ConclusionsThe knowledge synthesis methods and analytical process for NMAs are poorly reported and need improvement.Electronic supplementary materialThe online version of this article (doi:10.1186/s12916-016-0764-6) contains supplementary material, which is available to authorized users.