• About Life Cycle
    Life Cycle is an international, peer-reviewed, open access general medical journal and invites submissions of any original contribution that broadens, advances, or brightens medical science or practice, or that educates or delights the Journal’s readers. Building on the foundation of Life Cycle as the best science for medical health research, the Journal is committed to publishing high-quality and cutting-edge Original Research Articles, State-of-the-Art Reviews, and Letters that contribute to the advancement of healthy life from birth to senescence.

    CURRENT ISSUE: Jan 2024, Vol. 4

    Association of transitioning from combustible cigarettes to noncombustible nicotine or tobacco products with subsequent cancer risk: a nationwide cohort study in South Korea
    Life Cycle 2024;4:e2
    https://doi.org/10.54724/lc.2024.e2
    Trends in prevalence of asthma and COVID-19 pandemic-related factors in South Korea: a post-hoc analysis
    Life Cycle 2024;4:e1
    https://doi.org/10.54724/lc.2024.e1
    ABSTRACT
    Objective: There are only a few studies investigating the effects of the COVID-19 pandemic on the prevalence of asthma, especially between different age groups. Thus, we aimed to examine the trends of age-stratified asthma prevalence in South Koreans before and during the COVID-19 pandemic. Methods: This study utilized data derived from the Korea N...

    View More

    MOST READ ARTICLES

    Methods for testing statistical differences between groups in medical research: statistical standard and guideline of Life Cycle Committee
    Life Cycle 2022;2:e1
    https://doi.org/10.54724/lc.2022.e1
    HTML PDF PubReader

    Last 3 months views: 2250

    Regression analysis for continuous independent variables in medical research: statistical standard and guideline of Life Cycle Committee
    Life Cycle 2022;2:e3
    https://doi.org/10.54724/lc.2022.e3
    HTML PDF PubReader

    Last 3 months views: 2180

    Kaplan-Meier and Cox proportional hazards regression in survival analysis: statistical standard and guideline of Life Cycle Committee
    Life Cycle 2023;3:e8
    https://doi.org/10.54724/lc.2023.e8
    HTML PDF PubReader

    Last 3 months views: 1272

    Propensity score matching for causal inference and reducing the confounding effects: statistical standard and guideline of Life Cycle Committee
    Life Cycle 2022;2:e18
    https://doi.org/10.54724/lc.2022.e18
    HTML PDF PubReader

    Last 3 months views: 1147

    PRISMA 2020 statement and guidelines for systematic review and meta-analysis articles, and their underlying mathematics: Life Cycle Committee Recommendations
    Life Cycle 2022;2:e9
    https://doi.org/10.54724/lc.2022.e9
    HTML PDF PubReader

    Last 3 months views: 920

    Global Burden of Disease study at the World Health Organization: research methods for the most comprehensive global study of disease and underlying health policies
    Life Cycle 2022;2:e8
    https://doi.org/10.54724/lc.2022.e8
    HTML PDF PubReader

    Last 3 months views: 827

    Global, regional, and national incidence and mortality of COVID-19 in 237 countries and territories, January 2022: a systematic analysis for World Health Organization COVID-19 Dashboard
    Life Cycle 2022;2:e10
    https://doi.org/10.54724/lc.2022.e10
    HTML PDF PubReader

    Last 3 months views: 804

    The emerging pandemic recent: SARS-CoV-2
    Life Cycle 2023;3:e2
    https://doi.org/10.54724/lc.2023.e2
    HTML PDF PubReader

    Last 3 months views: 723

    Trends in prevalence of asthma and COVID-19 pandemic-related factors in South Korea: a post-hoc analysis
    Life Cycle 2024;4:e1
    https://doi.org/10.54724/lc.2024.e1
    HTML PDF PubReader

    Last 3 months views: 705

    N-Nitrosodimethylamine-contaminated ranitidine and risk of cancer in South Korea: a nationwide cohort study
    Life Cycle 2021;1:e1
    https://doi.org/10.54724/lc.2021.e1
    HTML PDF PubReader

    Last 3 months views: 636

    View More

    MOST CITED ARTICLES

    Methods for testing statistical differences between groups in medical research: statistical standard and guideline of Life Cycle Committee
    Life Cycle 2022;2:e1
    https://doi.org/10.54724/lc.2022.e1
    ABSTRACT
    In medical research, when independent variables are categorical (i.e., dividing groups), statistical analysis is often required. This situation mostly occurs on randomized controlled trials and observational studies that have multiple patient groups. Also, when analyzing continuous independent variables in a single patient group, breakpoints can be...
    HTML PDF PubReader

    Cited by 145

    Regression analysis for continuous independent variables in medical research: statistical standard and guideline of Life Cycle Committee
    Life Cycle 2022;2:e3
    https://doi.org/10.54724/lc.2022.e3
    ABSTRACT
    Variables measured in medicine are usually continuous, such as blood pressure, serum glucose, and drug dosage. There are statistical methods to confirm whether these variables act as independent variables that cause an outcome. Most of these methods are types of regression analysis. In this article, starting with a simple correlation coefficient, l...
    HTML PDF PubReader

    Cited by 79

    PRISMA 2020 statement and guidelines for systematic review and meta-analysis articles, and their underlying mathematics: Life Cycle Committee Recommendations
    Life Cycle 2022;2:e9
    https://doi.org/10.54724/lc.2022.e9
    ABSTRACT
    The paper discussed the overall aspects of systematic review and meta-analysis and explored the main mathematical context of meta-analysis. This included various methods of analyzing the effect size and obtaining the average effect size depending on the variable type. In doing so, methods of obtaining effect sizes in continuous outcome variables, c...
    HTML PDF PubReader

    Cited by 49

    Global, regional, and national incidence and mortality of COVID-19 in 237 countries and territories, January 2022: a systematic analysis for World Health Organization COVID-19 Dashboard
    Life Cycle 2022;2:e10
    https://doi.org/10.54724/lc.2022.e10
    ABSTRACT
    Objective: To estimate global, regional, and national incidences and mortality of the coronavirus disease 2019 (COVID-19) in 237 countries and territories since the outbreak of the COVID-19 pandemic to 31 January, 2022. Methods: Comprehensive estimates were produced through global, regional, and national studies of cumulative severe acute respirato...
    HTML PDF PubReader

    Cited by 30

    N-Nitrosodimethylamine-contaminated ranitidine and risk of cancer in South Korea: a nationwide cohort study
    Life Cycle 2021;1:e1
    https://doi.org/10.54724/lc.2021.e1
    ABSTRACT
    Objective: On September 2019, the United States Food and Drug Administration announced that some ranitidine products were contaminated with unacceptable levels of N-nitrosodimethylamine (NDMA). We aimed to determine whether the use of ranitidine that was potentially contaminated with NDMA, rather than another histamine H2-receptor antagonist (H2 bl...
    HTML PDF PubReader

    Cited by 21

    Global Burden of Disease study at the World Health Organization: research methods for the most comprehensive global study of disease and underlying health policies
    Life Cycle 2022;2:e8
    https://doi.org/10.54724/lc.2022.e8
    ABSTRACT
    The Global Burden of Disease (GBD) is a compass that navigates researchers and clinicians in discovering the latest knowledge and the current status of health for populations and countries worldwide. The GBD helps to present various methods in evaluating health-related quality of life and assess the health burden, economic burden, years of life los...
    HTML PDF PubReader

    Cited by 16

    Nationwide COVID-19 vaccination coverage and COVID-19 incidence in South Korea, January 2022: a national official report
    Life Cycle 2022;2:e2
    https://doi.org/10.54724/lc.2022.e2
    ABSTRACT
    Objective: To reduce the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, severe coronavirus disease 2019 (COVID-19) illness, and COVID-19 related death, all persons in South Korea should stay up to data with recommended COVID-19 vaccinations. This study investigated the rates and effectiveness of the COVID-19 vaccina...
    HTML PDF PubReader

    Cited by 15

    Propensity score matching for causal inference and reducing the confounding effects: statistical standard and guideline of Life Cycle Committee
    Life Cycle 2022;2:e18
    https://doi.org/10.54724/lc.2022.e18
    ABSTRACT
    Since the development of research methodology, there has always been keen interest in developing the accuracy of the research by comparing covariates. Propensity score is useful when the research covers many variables which are not intended to be included as independent variables, thus allowing the removal of certain covariates from the model. This...
    HTML PDF PubReader

    Cited by 14

    Vaccine strategy against COVID-19 with a focus on the Omicron and stealth Omicron variants: Life Cycle Committee Recommendations
    Life Cycle 2022;2:e5
    https://doi.org/10.54724/lc.2022.e5
    ABSTRACT
    The Severe Acute Respiratory Syndrome Coronavirus type 2 (SARS-CoV-2), the cause of the pandemic of coronavirus disease 2019 (COVID-19), was first discovered in December 2019 in Wuhan, China, and was consequently transmitted across the world. Further, within a year of its initial discovery, vaccines against SARS-CoV-2 were developed using diverse t...
    HTML PDF PubReader

    Cited by 12

    The emerging pandemic recent: SARS-CoV-2
    Life Cycle 2023;3:e2
    https://doi.org/10.54724/lc.2023.e2
    ABSTRACT
    The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), induces coughing, vomiting, or fever. The occurrence, duration, and severity of these symptoms vary from person to person, which makes symptoms of the COVID-19 infection ranging from those of a mild cold to death in severe cases. The cau...
    HTML PDF PubReader

    Cited by 12

    View More