A GBD 2021-Based Analytical Workflow to Estimate the Global Burden of Neoplasms Attributable to Low Physical Activity

Summary

This protocol demonstrates a reproducible workflow for extracting, processing, analyzing, and visualizing GBD 2021 estimates of neoplasms attributable to low physical activity. The workflow enables researchers to evaluate burden indicators, temporal trends, decomposition components, socioeconomic inequalities, and model-based projections using standardized population-level data.

Abstract

This protocol describes a reproducible analytical workflow for estimating the global burden of neoplasms attributable to low physical activity using Global Burden of Disease 2021 data. The workflow includes data extraction from the GBD Results Tool, definition of eligible outcomes and exposure categories, estimation of deaths, disability-adjusted life years, and age-standardized rates, temporal trend analysis using estimated annual percentage change and joinpoint regression, decomposition analysis, socioeconomic inequality assessment, and Bayesian age-period-cohort projection. The protocol also describes how to interpret uncertainty intervals, decomposition components, and inequality metrics in the context of modeled population-level estimates. As a representative application, the workflow was applied to colorectal cancer and female breast cancer attributable to low physical activity across 204 countries and territories from 1990 to 2021, with projections to 2045. This protocol can be adapted for other GBD risk-outcome pairs when researchers need a structured approach for risk-attributable burden estimation, trend characterization, inequality assessment, and projection analysis.

Introduction

Neoplasms represent a significant category of noncommunicable diseases (NCDs) contributing to global mortality and disability, posing a critical public health challenge worldwide. Globocan 2022 data revealed 19.96 million new neoplasm cases and 9.74 million deaths worldwide, with lung, breast (female), and colorectal cancers constituting the predominant malignancies. Projected cancer incidence will reach 35 million annually by 2050 (77% increase from 2022), with nations scoring low on the Human Development Index (HDI) projected to experience a 142% surge, driven by demographic transitions. Demographic expansion, population aging, deficient screening systems, and const....

Protocol

This study used publicly available, de-identified GBD 2021 population-level estimates. No individual-level human participant data were accessed. The GBD 2021 study received a waiver of informed consent from the University of Washington Institutional Review Board; therefore, no additional institutional ethical approval was required for this secondary analysis.

NOTE: This protocol describes a reproducible workflow for conducting a secondary analysis of GBD 2021 estimates for neoplasms¹¹ attributable to low physical activity. The workflow includes data extraction, variable definition, burden estimation, temporal trend a....

Results

Successful implementation of this protocol should generate a complete set of harmonized GBD-derived estimates across predefined locations, years, sexes, age groups, measures, and metrics. The expected outputs include age-standardized and age-specific burden estimates with 95% uncertainty intervals, EAPC and joinpoint trend estimates, decomposition components, SII and CII inequality metrics, and BAPC-based projections with posterior uncertainty intervals. A suboptimal implementation is indicated by missing strata, inconsi.......

Discussion

This GBD 2021 analysis shows two contrasting patterns in low physical activity-attributable neoplasm burden. While ASMR and ASDR for neoplasms attributable to LPA significantly declined from 1990 to 2021 (ΔASMR = -19.72%; ΔASDR = -18.51%), absolute deaths and DALYs increased by 95.73% and 84.79%, respectively. The increase in absolute burden despite declining age-standardized rates was mainly explained by population growth and population aging. Declining ASRs may reflect multiple factors, including improvements.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Bayesian Age-Period-Cohort (BAPC) R Package	R Foundation / CRAN Repository	https://cran.r-project.org/	Used for Bayesian age-period-cohort projection analyses.
CSV Data Files	Institute for Health Metrics and Evaluation (IHME)	N/A	Exported burden datasets from GBD 2021 Results Tool for downstream analysis.
dplyr R Package	R Foundation / CRAN Repository	https://cran.r-project.org/package=dplyr	Used for data manipulation and cleaning in R.
GBD 2021 Data Input Sources Tool	Institute for Health Metrics and Evaluation (IHME)	https://ghdx.healthdata.org/gbd-2021	Public repository for GBD source documentation.
ggplot2 R Package	R Foundation / CRAN Repository	https://cran.r-project.org/package=ggplot2	Used for graphical visualization of temporal trends and inequality analyses.
Global Burden of Disease (GBD) 2021 Results Tool	Institute for Health Metrics and Evaluation (IHME)	https://vizhub.healthdata.org/gbd-results/	Public database used for extraction of deaths, DALYs, ASMR, and ASDR data.
INLA R Package	R-INLA Project	https://www.r-inla.org/	Used for Bayesian inference within age-period-cohort modeling.
JD_GBDR Software	Jingding Medical Technology Co., Ltd.	Version 2.37.1	Used for GBD burden estimation, decomposition analysis, and standardized rate visualization.
Joinpoint Regression Program (Version 5.3.0)	National Cancer Institute (NCI)	https://surveillance.cancer.gov/joinpoint/download	Used for joinpoint regression analysis, APC, and AAPC estimation.
Microsoft Excel	Microsoft Corporation	https://www.microsoft.com/excel	Used for organizing and cleaning extracted CSV datasets prior to analysis.
Personal Computer Workstation	Any standard computing workstation	N/A	Recommended minimum: 8 GB RAM, Windows 10/11 or macOS for statistical analyses and projections.
R Statistical Software (Version 4.4.2)	R Foundation for Statistical Computing	https://www.r-project.org/	Used for statistical analysis, EAPC calculation, inequality analysis, visualization, and Bayesian age-period-cohort modeling.
RStudio Desktop	Posit Software, PBC	https://posit.co/download/rstudio-desktop/	Integrated development environment for R analyses.