Mortality data is comprised of the number of deaths by age group, cause of death, sex, year, and country or area. Age group is reported in one of nine different age groupings. Cause of death is coded using a three character International Classification of Disease code (ICD), internally developed and maintained by WHO. Country or area is a four digit code representing the reporting unit.
Mortality data includes several ancillary translation tables including ICD codes, WHO region, and country or area reporting unit. The data store also contains supplementary population data which is used to calculate mortality rates and other statistics.
The attention of the potential user is also drawn to the fact that selected presentations from the data base are published in hard copy annually in the World Health Statistics Annual that can be found in most large public, and university libraries. The Annual offers the reader in particular a succinct 3-page display of each country-year of deaths by cause, and of age and sex-specific mortality rates.
The cause-of-death labels used vary over time according to the version of the International Classification of Diseases used. The International Classification of Diseases (ICD) has been revised ten times since its first formulation in the 19th century. The data base was established after the sixth revision (ICD6) of 1948. ICD7 was published in 1955, ICD8 in 1965, ICD9 in 1975, and ICD10 in 1992. Countries did not necessarily all adopt a new revision in the year it appeared, so the switch from one revision to the next is generally staggered. The total number of labels in any Classification is large, and cells would be quite small or empty in the case of rarer diagnostic categories. Consequently, none of the Classifications have been exhaustively applied to label causes; each Revision has an accompanying shorter list for purposes of parsimony and information storage. For ICD6, ICD7, and ICD8, there is list A (150 causes) or List B (50 causes). For ICD9, there is the Basic Tabulation List or BTL, that provides greater flexibility and variability in the number of cause labels that can be utilized. In the special case of neoplasms, furthermore, under the provisions of ICD6, ICD7, ICD8, and ICD9, Member States may choose also to provide detailed cause-of- death data for about 100 cancer sites. ICD10 has provisions for a condensed list of 103 causes, or a selected list of 80 causes, as well as specialized lists for infant and child mortality. The degree to which equivalent causes may be tracked from one Revision to another depends on the stability of a label - the time trend for some important causes has accordingly been well documented - or, for labels that change, depends on the extent to which the causes subsumed in a label can be distinguished and tracked from Revision to Revision. Tracking is easier if there is tolerance for less detail, and some loss of information is acceptable.
The age groups employed vary by country and may vary for one country over time. Countries may group deaths according to five-year (or ten-year) age groups between 5 and 9 (or 5 and 14) years and from 60 to 64 (or 55 to 64) years. Age groups under 5 years of age are variable; some countries use age 0 and age 1-4 years grouped, and others use age 0 and years 1, 2, 3, 4 in single years. Similarly, the existence and grouping of death data for the population over 64 varies: deaths to the older population exist grouped for all ages 65 and over, 70 and over, 75 and over, or 85 and over. Furthermore, there are combinations of the different groupings for the youngest and oldest ages: at present 9 age codes exist in the data base, including deaths provided without reference to age. Finally, the ages employed to classify infant deaths - deaths at age 0 years - also vary, in particular for the neonatal period: deaths may or may not be separately reported that occurred in the first 28 days, whereas in some cases, neonatal reports are complete for deaths on day 0, in week 1 (days 1 to 6), in the first four weeks (days 7-27), or subsequently (days 28-364).
The sex is provided for all deaths by all countries. The fact that there are sex-specific causes of death (for example, prostate cancer, ovarian cancer, or obstetric causes) serves to help validate the data submitted. The population for each age-sex group is provided for each country-year in the data base to enable users to calculate mortality rates and derive measures such as life expectancies.
Additional Datasets may be located through CIESIN's Gateway.