Construction of multilevel statistical models in health research: Foundations and generalities.

This topic review aims to present a global vision of multilevel analysis models’ applicability to health research, explaining its theoretical, methodological, and statistical foundations. We describe the basic steps to build these models and examples of their application according to the data hierarchical structure. It ir worth noticing that before using these models, researchers must have a rationale for needing them, and a statistical evaluation accounting for the variance percentage explained by the observations grouping effect.

Exposure to low-dose radiation in occupational settings and ischaemic heart disease: a systematic review and meta-analysis.

Ionising radiation is a human carcinogen, but the evidence is less clear that exposure to low-dose ionising radiation (LDIR) increases the risk of adverse cardiovascular outcomes. We synthesised the literature of chronic occupational exposure to LDIR and cardiovascular disease, particularly for ischaemic heart disease (IHD).The literature search was conducted using three databases including studies published between 1990 and 2022.

Latin America and the Caribbean Code Against cancer 1st edition: Environment, occupation, and cancer.

Within the framework of the Latin America and Caribbean region (LAC) Code Against Cancer 1st edition, the current work presents recommendations to reduce exposure to environmental and occupational carcinogenic agents relevant for LAC. Using the methodology established by the International Agency for Research on Cancer (IARC) in the World Code Against Cancer Framework and experience from developing the European Code Against Cancer 4th edition, a working group of LAC cancer-prevention experts reviewed the list of Group I IARC carcinogenic agents, identified prevalent environmental and occupational exposures in the region, and proposed evidence-based cancer prevention recommendations suited to the epidemiological, socioeconomic, and cultural conditions of LAC countries. Two sets of recommendations were drafted: those targeting the general public and a second set for policymakers.

Barriers and facilitators of academia-government collaboration in the context of the COVID-19 pandemic in Colombia: a qualitative study.

The COVID-19 pandemic highlighted the importance of strengthening collaborations between academia and government. The development and maintenance of these collaborative relationships is a complex and dynamic process, particularly during public health emergencies. This study was aimed at identifying and analysing factors that acted as barriers and facilitators in the collaboration process between academia and government during the COVID-19 pandemic in the five largest cities in Colombia.

Validation of RT-qPCR test for SARS-CoV-2 in saliva specimens.

Background: Saliva samples may be an easier, faster, safer, and cost-saving alternative to NPS samples, and can be self-collected by the patient. Whether SARS-CoV-2 RT-qPCR in saliva is more accurate than in nasopharyngeal swaps (NPS) is uncertain. We evaluated the accuracy of the RT-qPCR in both types of samples, assuming both approaches were imperfect.

Clustering of non-leukemia childhood cancer in Colombia: a nationwide study.

Childhood cancer is considered one the most important causes of death in children and adolescents, despite having a low incidence in this population. Spatial analysis has been previously used for the study of childhood cancer to study the geographical distribution of leukemias. This study aimed to identify the presence of space-time clusters of childhood of cancer excluding leukemia in Colombia between 2014 and 2017.

Socioeconomic inequalities associated with mortality for COVID-19 in Colombia: a cohort nationwide study.

Background: After 8 months of the COVID-19 pandemic, Latin American countries have some of the highest rates in COVID-19 mortality. Despite being one of the most unequal regions of the world, there is a scarce report of the effect of socioeconomic conditions on COVID-19 mortality in their countries. We aimed to identify the effect of some socioeconomic inequality-related factors on COVID-19 mortality in Colombia.

Childhood Leukemia in Small Geographical Areas and Proximity to Industrial Sources of Air Pollutants in Three Colombian Cities.

Acute leukemia is the most common childhood cancer and has been associated with exposure to environmental carcinogens. This study aimed to identify clusters of acute childhood leukemia (ACL) cases and analyze their relationship with proximity to industrial sources of air pollution in three capital cities in Colombia during 2000-2015. Incident ACL cases were obtained from the population cancer registries for the cities of Bucaramanga, Cali, and Medellín.

A spatial analysis of childhood cancer and industrial air pollution in a metropolitan area of Colombia.

Background: Air pollutants are considered carcinogenic to humans. In some European countries, an association between industrial air pollution and childhood cancer has been established. This relationship has not been addressed in Latin America, despite the spatial variability of air pollutants that may limit the extrapolation of the results to other geographical areas.

Space-time clustering of childhood leukemia in Colombia: a nationwide study.

Background: Leukemia is the most common cancer in childhood. The estimated incidence rate of childhood leukemia in Colombia is one of the highest in America and little is known about its spatial distribution.

Purpose: To explore the presence of space-time clustering of childhood leukemia in Colombia.

Monthly-Term Associations Between Air Pollutants and Respiratory Morbidity in South Brazil 2013-2016: A Multi-City, Time-Series Analysis.

Most air pollution research conducted in Brazil has focused on assessing the daily-term effects of pollutants, but little is known about the health effects of air pollutants at an intermediate time term. The objective of this study was to determine the monthly-term association between air pollution and respiratory morbidity in five cities in South Brazil. An ecological time-series study was performed using the municipality as the unit of observation in five cities in South Brazil (Gravataí, Triunfo, Esteio, Canoas, and Charqueadas) between 2013 and 2016.

Short-term joint effects of ambient air pollutants on emergency department visits for respiratory and circulatory diseases in Colombia, 2011-2014.

Background: We evaluated the short-term effect of mixtures of ambient air pollutants on respiratory and circulatory morbidity in four Colombian cities.

Methods: Daily Emergency Department (ED) visit records for respiratory and circulatory selected diagnosis and daily concentrations for six criteria air pollutant were obtained in four of the five major cities in Colombia: Bucaramanga, Bogota, Cali, and Medellin during 2011-2014. Using conditional Poisson time series analysis with fixed effects, we assessed the effect of air pollutants on health outcomes using single-pollutant, two-pollutant and specific mixtures-of-pollutant models controlling for meteorology and time trends.

Reporting of statistical regression analyses in Biomédica: A critical assessment review.

Introduction: Regression modeling is a statistical method commonly used in health research, especially by observational studies. Objective: The objectives of this paper were to 1) determine the frequency of reporting of regression modeling in original biomedical and public health articles that were published in Biomédica between 2000 and 2017; 2) describe the parameters used in the statistical models, and 3) describe the quality of the information reported by the studies to explain the statistical analyses. Materials and methods: We conducted a critical assessment review of all original articles published in Biomédica between 2000 and 2017 that used regression models for the statistical analysis of the studies main objectives.

Short-Term Effects of Air Pollution on Respiratory and Circulatory Morbidity in Colombia 2011⁻2014: A Multi-City, Time-Series Analysis.

Few studies have been conducted on the effect of air pollution on morbidity in Latin America. This study analyzed the effects of air pollution on respiratory and circulatory morbidity in four major cities in Colombia. An ecological time-series analysis was conducted with pollution data from air quality monitoring networks and information on emergency department visits between 2011 and 2014.

No effect of mercury exposure on kidney function during ongoing artisanal gold mining activities in Colombia.

This cross-sectional study examined whether people who are exposed to mercury (Hg) vapours in ongoing artisanal gold mining activities have alteration in kidney function monitoring parameters. The study enrolled 164 miners and 127 participant controls. The Hg concentrations for miners and control participants were measured in blood (B-Hg; median 7.

[Human mercury exposure and irregular menstrual cycles in relation to artisanal gold mining in Colombia].

Introduction: Artisanal mining commonly extracts gold with an amalgamation process that uses mercury. The reproductive effects from exposure to elemental mercury used in gold mining have not been sufficiently studied.

Objective: To evaluate the effect of the exposure to elemental mercury used in gold mining on menstrual cycle regularity and the occurrence of miscarriages in Colombia.

The effects of outdoor air pollution on the respiratory health of Canadian children: A systematic review of epidemiological studies.

Background: Outdoor air pollution is a global problem with serious effects on human health, and children are considered to be highly susceptible to the effects of air pollution.

Objective: To conduct a comprehensive and updated systematic review of the literature reporting the effects of outdoor air pollution on the respiratory health of children in Canada.

Methods: Searches of four electronic databases between January 2004 and November 2014 were conducted to identify epidemiological studies evaluating the effect of exposure to outdoor air pollutants on respiratory symptoms, lung function measurements and the use of health services due to respiratory conditions in Canadian children.

Lack of autoantibody induction by mercury exposure in artisanal gold mining settings in Colombia: Findings and a review of the epidemiology literature.

Mercury (Hg) has been implicated as an immunotoxicant in experimental animal models, but its role in the induction of human autoimmunity remains unclear due to contradictory findings. Therefore, it has been claimed that it is important to examine other populations in order to clarify the role of Hg in these diseases. The aim of this study was to investigate whether occupational Hg exposure due to artisanal gold mining is associated with the prevalence of autoimmune biomarkers.

Epidemiology, risk factors and genotypes of HBV in HIV-infected patients in the northeast region of Colombia: high prevalence of occult hepatitis B and F3 subgenotype dominance.

Introduction: Chronic hepatitis B virus (HBV) infection is an increasing cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected individuals. HIV-positive patients are commonly co-infected with HBV due to shared routes of transmission.

Objectives: Our aim was to determine the risk factors, prevalence, genotypes, and mutations of the Surface S gene of HBV, and occult hepatitis B infection (OBI) among patients infected with HIV in a northeastern Colombian city.

The effects of air pollution on respiratory health in susceptible populations: a multilevel study in Bucaramanga, Colombia.

We conducted a cohort study to investigate the association between exposure to three different levels of outdoor air pollution and incidence of respiratory symptoms in a population with chronic cardiovascular and respiratory disease. We accompanied 756 participants for a period of six months through the maintenance of a daily record of symptoms and clinic visits. The symptoms with highest incidence rates were sneezing and hacking cough.