Occupational Exposures and Risks of Non-Hodgkin Lymphoma: A Meta-Analysis.

Non-Hodgkin lymphoma (NHL) is a heterogeneous group with different types of diseases. It remains unclear as to what has led to an increase in incidences of NHL, however, chemical substance exposure is known to be one of the risk factors for the disease. Therefore, we performed a systematic review and meta-analysis including case-control, cohort, and cross-sectional observational epidemiological studies to verify the association between occupational exposure to carcinogens and NHL risk. Articles between the years 2000 and 2020 were collected. Two different reviewers performed a blind selection of the studies using the Rayyan QCRI web app. Post-completion, the selected articles were extracted and analyzed via the RedCap platform. Our review resulted in 2719 articles, of which 51 were included in the meta-analysis, resulting in an overall OR of 1.27 (95% CI 1.04-1.55). Furthermore, it was observed that the main occupation associated with the increased risk of NHL was that in which workers are exposed to pesticides. We therefore conclude that the evidence synthesis of the epidemiological literature supports an increased risk for NHL, regardless of subtype, considering occupational exposure to certain chemical compounds, mainly pesticides, benzene, and trichlorethylene, and certain classes of work, primarily in the field of agriculture.

The Impact of International Research Collaborations on the Citation Metrics and the Scientific Potential of South American Palliative Care Research: Bibliometric Analysis.

Background: Progress in palliative care (PC) requires scientific advances which could potentially be catalyzed by international research collaboration (IRC). It is currently not known how often IRC occurs with PC investigators in South America. Objectives: To evaluate the percentage of South America journal articles on PC involving IRCs and the impact of these collaborations on the scientific potential the studies and on their citations. Methods: This was a bibliometric analysis of studies published between January 1, 1998, and December 31, 2017. A search of Pubmed, Embase, Lilacs, and Web of Science (WOS) was performed using the terms "palliative care," "hospice care," "hospices" and "terminal care," combined with the name of South America countries. The scientific potential was assessed by analyzing study design, characteristics of the journal and funding. IRCs were further subdivided in internal (within South America countries) and external (with countries outside South America). Findings: Of the 641 articles, 117 (18.2%) involved IRCs (internal: 18, 2.8%; external: 110, 17.2%). Articles with IRCs had higher median two-year citations in WOS (2 vs. 1, p < 0.001), Scopus (3 vs. 1, p < 0.001) and Google Scholar (4.5 vs. 2, p < 0.001) compared to articles without IRC. Moreover, they were more often funded (40.7% vs. 9.7%, p < 0.001), published in Pubmed-indexed (76.1% vs. 41.6%; p < 0.001) and in WOS-indexed (70.1% vs. 29.6%; p < 0.001) journals, and with study designs most often classified as clinical trial (5.1% vs. 1.0%; p = 0.002) and cohort (10.3% vs. 2.9%; p < 0.001) compared to articles without IRC. Conclusions: Studies with international research collaborations, both internal and external to South America, are more frequently cited and have characteristics with greater scientific potential than do studies without international collaborations.

Characteristics of Palliative Care Publications by South American Authors in the Last 20 Years: Systematic Literature Review With Bibliometric Analysis.

CONTEXT: Research on palliative care (PC) can be used as a direct measure to assess the level of PC development in a country or region. OBJECTIVES: To investigate the scientific production in the field of PC in South American countries over the last two decades. METHODS: The search was performed using the terms "palliative care," "hospice care," "hospices," and "terminal care" combined with the names of South American countries in several databases. The trend in publications over time was analyzed by linear equations (R2) and by calculating the annual percentage change (APC). The article citations were extracted from Web of Science (WOS), Scopus and Google Scholar, and the countries' impact factors (IFc) were calculated. RESULTS: Of the 4259 identified articles, 641 were included in the analysis. There was a clear increase in the number of publications over the analyzed period (R2 = 0.8794, APC = 14.42%). Brazil was the country with the highest number of publications (n = 389); however, after adjustments by population, GDP and number of researchers, Chile was the country with the greatest prominence, including the highest IF in WOS (4.409). Only 8.3% of publications were systematic review, clinical trial or cohort studies; only 15.4% were funded. CONCLUSION: This bibliometric review identified an annual increase of 14% in the number of scientific publications by researchers from South America over the last 20 years. Although Brazil produced the most articles, Chile, had the most efficient scientific production. In general, the articles had low potential for scientific impact.