Objetivos:
¿Aumenta un nivel bajo de selenio en los tejidos humanos el riesgo de cáncer de mama?

Diseño del estudio:
Este artículo de revisión incluyó 18 estudios de casos y controles con 3,374 mujeres diagnosticadas con cáncer de mama (grupo de casos) y 3,582 controles sanos (mujeres sin cáncer de mama).

Objectives:
What is the weighted average incidence of pulmonary thromboembolism (PTE) in COVID-19 patients who were admitted to the intensive care unit (ICU)?

Study design:
This review article included 14 observational studies with a total of 1,182 COVID-19 patients Almost all patients in this meta-analysis (review article) received at least prophylactic anticoagulation.

Males was a significant source of heterogeneity [p = 0.03, 95% CI = 0.00 to -0.09].

Results and conclusions:   

Objectives:
Do rheumatic diseases increase COVID-19 severity and fatality?

Study design:
This review article included 31 articles involving 1,138 COVID-19 patients.
The publications were from Europe, Asia and North America, but none from other continents.
There were 10 studies which only included hospitalized patients.
About 64% of the patients were female.
There was no publication bias.

Results and conclusions:   

Objectives:
Data on efficacy of hepatitis-B vaccine (HBV) in patients with inflammatory bowel disease (IBD) is limited. Therefore, this review article has been conducted.

What is the efficacy of hepatitis-B vaccine (HBV) in patients with inflammatory bowel disease (IBD)?

Study design:
This review article included 14 studies with 2,375 patients.
4 data sets were available from 2 studies that compared HBV response in patients with IBD against healthy controls.

Objectives:
Famotidine was reported to potentially provide benefits to Coronavirus Disease 2019 (COVID-19) patients. However, it remains controversial whether it is effective in treating COVID-19. Therefore, this review article has been conducted.

Objectives:
To date, there is no definite effective treatment for the COVID-19 pandemic. Therefore, this review article has been conducted.

What is the effective treatment for the COVID-19 patients?

Study design:
This review article included 25 RCTs (which compared the effect of any pharmacological drugs versus standard care or placebo 28-day after hospitalization in adult patients with COVID-19 disease), evaluating 17 different treatments and 11,597 participants.

Objectives:
Fish oil has been shown to reduce the risk of metabolic disorders. However, the effects of fish oil intervention on glucose metabolism and insulin sensitivity are still controversial, especially in children. Therefore, this review article has been conducted.

Objectives:
Since the beginning of 2020 the SARS-CoV-2 virus (COVID-19) has spread to nearly every country in the world. The mainly airborne pathogen has led to large numbers of deaths, principally in elderly and vulnerable segments of the population. Protective vaccines have recently become available, but it is not yet clear whether and when population-wide immunity will be achieved. The existence of evidence for the protective effect of masks covering the mouth and nose is a topic of public debate. Therefore, this review article has been conducted.

Objectives:
Vitamin D deficiency during pregnancy or infancy is associated with adverse growth in children. No systematic review has been conducted to summarize available evidence on the effect of vitamin D supplementation in pregnancy and infancy on growth and body composition in children. Therefore, this review article has been conducted.