Choose between records and estimates
The Civil Registration System compiles registered births, deaths and other vital events. Its totals reflect what entered the registration system under the report’s timing and coverage rules. The Sample Registration System provides estimates of fertility and mortality. A registered event count and an estimated rate complement each other, but they are not the same measure.
Read the denominator and time window
Birth and death rates, infant mortality and maternal mortality use different denominators. A maternal mortality ratio is expressed per live births, rather than as a share of all women. Its published estimate may pool several years. Keep the entire reference period visible: a bulletin released in 2026 can describe events or estimated conditions from earlier years.
For registered totals, inspect whether the table uses year of occurrence, registration or another convention. Delayed registrations and changes in completeness can affect annual totals. An increase in registered events alone does not isolate a change in the underlying demographic rate.
Understand survival and cause measures
A period life table applies the reference period’s mortality conditions to a hypothetical cohort. Life expectancy at birth is a summary of those conditions, not the average age among people who died or a prediction of one person’s eventual lifespan. Remaining life expectancy at a later age answers a different question.
Medical Certification of Cause of Death reports describe medically certified deaths. A cause’s share within that group should not be presented as its share of all deaths or as disease prevalence among living people.
Use the latest relevant evidence carefully
Start with the source guide for the measure you need and follow the original report’s table notes. Some sources listed here have verified official catalogue metadata without reproduced numeric tables. Where that is the case, use the guide to locate evidence; do not infer an unverified figure from a report title or publication date.