Incidence, prevalence, DALYs: reading GBD numbers correctly
2 October 2026 · Cohira team
GBD estimates let you describe the burden of any disease, in any country, over three decades, without collecting a single record.
The four core metrics
Incidence counts new cases. Prevalence counts existing ones. Deaths are attributed by cause. DALYs add the time dimension: years lost to early death plus years lived with disability, one number for the total burden.
Age-standardised or crude?
Crude rates answer service-planning questions; age-standardised rates answer comparison questions. Papers that mix the two draw conclusions the data does not support.
What a strong GBD paper adds
Not the numbers themselves, which are public, but the analysis on top: trends, joinpoints, inequality between regions, projections, and a clinical interpretation the estimates alone cannot give.