:: WHO Mortality Database: Tables
On this web site, the World Health Organization provides data on registered deaths by
From national vital registration systems
The data available on this web site comprise deaths registered in national vital registration systems, with underlying cause of death as coded by the relevant national authority. Underlying cause of death is defined as "the disease or injury which initiated the train of morbid events leading directly to death, or the circumstances of the accident or violence which produced the fatal injury" in accordance with the rules of the International Classification of Diseases.
Historical data from 1979
The mortality data were previously published in the World Health Statistics Annual and the 1996 edition was the last one to appear in printed form. Since then the new data supplied by Member States have been made available online As the demand for information increases, the mortality data with the cause of death coded using the ICD 9th and 10th Revision are now being made available on this site. The tables online follow the same format as that of the previous updates but contain historical data as from 1979 to 2002. This major increase in the number of countries-years available on line will certainly meet the needs of scientists, researchers and public health policy makers. Mortality rates by sex, age group and cause are presented for countries with a population of 500,000 or more. Rates are not computed for data with very low coverage.
Comparability through the use of ICD
Comparability of cause of death data has been made possible world-wide through the development and revisions of the International Statistical Classification of Diseases and Related Health Problems (ICD). The ICD10th revision was adopted in 1990 by the World Health Assembly and came into effect as from 1993. The number of countries submitting their underlying causes of death data to WHO using ICD10th revision has increased from 4 in 1995 to 75 in 2003 and there are still around 40countries reporting data using the 9th revision of ICD. Only countries reporting data properly coded according to the revisions of the ICD are included in the Tables of this web site.
Problems in accuracy of records
Although the International Classification of Diseases is intended to provide a standard way of recording underlying cause of death, comparison of cause of death data over time and across countries should be undertaken with caution. Several new features and changes from ICD9 to ICD10 have great impact on the interpretation of the statistical data. The implications of these changes in ICD10 should be taken into account when making trend comparisons and estimates for causes of death. ICD10 is more detailed with about 10 000 conditions for classifying causes of death compared to around 5 100 in ICD9. The rules for selecting the underlying cause of death have been re-evaluated and sometimes changed.
Accuracy in diagnosing causes of death still varies from one country to another. In addition the process of coding underlying causes of death involves some extent of misattribution or miscoding even in countries where causes are assigned by medically qualified staff. Main reasons are incorrect or systematic biases in diagnosis, incorrect or incomplete death certificates, misinterpretation of ICD rules for selection of the underlying cause, and variations in the use of coding categories for unknown and ill-defined causes.
:: WHO Mortality Database: Tables
Completeness and coverage of death registration data
Considerable differences exist in the degree of completeness of the vital registration data submitted by countries. In some countries, the vital registration data system covers only a part of the country (for example urban areas, or some provinces only). In some other countries, although the vital registration data system covers the whole country, not all deaths are registered.
Each Member State reports population data along with their mortality data, for the population covered by the death registration system. Where this is a subset of the national population, the data is labelled accordingly in the WHO Mortality Database, e.g. Brazil (North and North-east) or Paraguay (reporting areas). However, the completeness of death registration may also be less than 100% for the specified registration population. For Member States with incomplete vital registration systems, demographic techniques have been used by WHO to estimate the level of completeness of death recording for the specified population to allow the calculation of mortality rates. These population data are provided along with the deaths data. The proportion of all deaths which are registered in the population covered by the vital registration system for a country (referred to as completeness) has been estimated by WHO for the latest available year and is given in a table available on this website
Note that vital registration data may be 100% complete for the population covered, but not include full coverage of deaths in the country. The overall level of coverage for the latest available year for each country is also listed in a separate table. Coverage is calculated by dividing the total deaths reported for a country-year from the vital registration system by the total estimated deaths for that year for the national population. The national population estimates used are those of the UN Population Division 2002 revision. Best estimates of mortality rates by age and sex, adjusted for incompleteness and incomplete coverage, are applied to the national population data to obtain total estimated deaths. WHO estimated coverage for a Member State may be less than 100% due to incompleteness of registration, or to coverage of only some parts of the national population, or to differences between the vital registration population and the UN estimated de-facto population.
Death registration coverage and cross-national differences in coding practices, particularly in the use of codes for ill-defined and unknown causes, must be taken into account to validly compare mortality rates for specific causes across countries. Additionally, where coverage is less than 100%, the cause of death distribution for the uncovered population may differ from that of the covered population.
:: WHO Mortality Database: Tables
Updating the database and Querying about the database
Member states submit data
WHO contacts Member States directly on a routine basis to obtain latest cause of death data from their vital registration sources. Data submitted by Member states become part of WHO's unique historical data base on causes of death, which contains data as far back as 1950. Computerization of data at country level and electronic transmission to WHO have considerably improved the timeliness of information received.
From print to the web
WHO started the publication of cause of death statistics in 1948 in the annual editions of the Annual Epidemiological and Vital Statistics. The 1962 and subsequent editions were renamed as the World Health Statistics Annual. The 1996 edition was the last to appear in printed form. With the advent of new technology, mortality statistics have been provided on this Web site since July 2000 and include all data received since the 1996 edition of the World Health Statistics Annual. The current update features for the first time all the historical data as from 1979 to 2002 using ICD 9th and ICD 10th revision in the usual friendly user format. Regular updates to the WHO mortality database will be undertaken as data are received from Member States to ensure that the latest data are available.
Two classes of data: Country-reported and WHO estimate
The two classes of mortality information available on the WHO web site may be distinguished as follows. a) Mortality registration data reported by Member States (as described above) b) WHO estimated mortality data for 2000, 2001 and 2002 WHO itself uses the historical data from the mortality data base as a basis to derive WHO estimates of deaths by cause as published in Annex Tables to the World Health Report. More detailed tables for WHO estimates of total deaths by cause, age and sex for WHO regions and subregions may be downloaded from the website. (Insert link to the Burden of Disease web site) These estimates are sets of population age-specific mortality rates or numbers that are adjusted to make them comparable across populations. Comparability requires in addition the use of the same measurement scale (in this case classification of underlying cause). Adjustments with regard to incomplete coverage are made. Particular attention is also being paid to the problems of miscoding mainly for cardiovascular diseases, cancer, injuries and general ill-defined categories. Correction algorithms to resolve these miscoding problems have been developed and applied (Discussion Paper 54) (insert link to Burden of Disease web site). Trend data from countries with good vital registration system serve as a basis for validating projected estimates. WHO estimated mortality data is primarily intended for use by policy makers and analysts. As an international organization, information published by the WHO is frequently used for benchmarking, for advocacy of particular policies, for monitoring achievements towards internationally accepted goals and targets and to guide technical strategies and responses.
Most queries on the reported data can be answered on the basis of the data from this web site and from the yearly publication of data for earlier years in the World Health Statistics Annual. This publication can be consulted at most major libraries throughout the world.