International journal of epidemiology最新文献

Motivation: The Peter Clark (PC) algorithm is a popular causal discovery method to learn causal graphs in a data-driven way. Until recently, existing PC algorithm implementations in R had important limitations regarding missing values, temporal structure or mixed measurement scales (categorical/continuous), which are all common features of cohort data. The new R packages presented here, micd and tpc, fill these gaps.

Implementation: micd and tpc packages are R packages.

General features: The micd package provides add-on functionality for dealing with missing values to the existing pcalg R package, including methods for multiple imputations relying on the Missing At Random assumption. Also, micd allows for mixed measurement scales assuming conditional Gaussianity. The tpc package efficiently exploits temporal information in a way that results in a more informative output that is less prone to statistical errors.

Availability: The tpc and micd packages are freely available on the Comprehensive R Archive Network (CRAN). Their source code is also available on GitHub (https://github.com/bips-hb/micd; https://github.com/bips-hb/tpc).

Background: COVID-19 vaccine effectiveness (VE) studies leveraging systematic surveillance in sub-Saharan Africa are limited. We assessed the effectiveness of two vaccines (Pfizer BNT162b2 and Johnson & Johnson Ad26.COV2.S) against SARS-CoV-2-associated hospitalization in South African adults aged ≥18 years.

Methods: We conducted a test-negative case-control study using pneumonia surveillance data in South Africa. Inpatients with physician-diagnosed lower respiratory tract infection or suspected COVID-19, testing SARS-CoV-2 positive or negative from June 2021-March 2022, were cases or controls, respectively. Fully vaccinated individuals received one Ad26.COV2.S dose or two BNT162b2 doses ≥14-days before enrollment. VE was estimated using multivariable logistic regression for Delta- and Omicron BA.1/BA.2-predominant periods, stratified by age and HIV status.

Results: The study included 925 cases and 1890 controls; 38 (4%) cases and 186 (10%) controls were fully vaccinated with BNT162b2, and 30 (3%) cases and 94 (5%) controls with Ad26.COV2.S. The vaccine effectiveness of BNT162b2 against SARS-CoV-2-associated hospitalization over Delta and Omicron BA.1/BA.2 periods was 91% (95% CI: 52%, 98%) and 33% (-16%, 86%), respectively. The vaccine effectiveness of Ad26.COV2.S against hospitalization over Delta and Omicron BA.1/BA.2 periods was 72% (-36% ,94%), and -19% (-130%, 39%), respectively. The vaccine effectiveness of BNT162b2 against hospitalization over the Delta period was 94% (50%, 99%) and 89% (27%, 98%) among adults aged ≥60 years and HIV-uninfected, respectively.

Conclusions: The BNT162b2 vaccine was effective against SARS-CoV-2-associated hospitalization during the Delta period for adults aged ≥18 years, ≥60 years and those HIV-uninfected. VE for Ad26.COV2.S was inconclusive, potentially due to limited sample size or residual confounding. These findings highlight the utility of sentinel surveillance for estimating VE.

Background: Colorectal cancer remains a major global public health challenge. Its incidence is shaped by a complex interplay of screening programmes and age, period and cohort factors.

Methods: We introduce a novel Age-Period-Cohort-Screening (APCS) model to analyse trends in colorectal cancer incidence in Taiwan from 2000 to 2019.

Results: In 2010, the incidence of colorectal cancer in Taiwan increased by 19.2% (95% CI: 13.5%, 25.3%) for men and 15.6% (95% CI: 9.2%, 22.4%) for women. This was followed by annual declines of 3.4% (95% CI: 2.8%, 4.1%) and 3.1% (95% CI: 2.4%, 3.9%), respectively. By 2015 for men and 2014 for women, the age-standardized incidence had fallen below the levels projected in a no-screening scenario. By 2019, the incidence had further declined by 12.4% (95% CI: 11.8%, 13.1%) for men and 11.6% (95% CI: 10.7%, 12.6%) for women, compared with the no-screening scenario. Cohort effects have shown a persistent rise from 1920 to 1980: incidence increased 5.8-fold for men and 3.1-fold for women. The trend began to plateau after 1980, with a noticeable decline in women.

Conclusion: Through its screening programme, Taiwan has successfully reduced colorectal cancer incidence by 10% as of 2019. Furthermore, the incidence due to cohort effects has plateaued and even begun to decline. However, continued monitoring remains crucial. The advanced APCS model could serve as a robust analytical tool for other researchers and policy makers evaluating the impacts of cancer screening programmes on incidence trends.