Methodology

The Canadian Human Mortality Database (CHMD) contains uniform death rates and life tables for Canada, provinces and territories. A complete description of the methodology is presented in the Methods Protocol, available on the Human Mortality Database's web site.

Mortality rates and life tables computations

The following is a brief summary of principles guiding the calculation of mortality rates and life tables:

  1. Births
  2. Annual counts of live births by sex are collected for all Canadian provinces and territories over the longest time period available. These counts are used for various adjustments based on relative cohort size, namely the measure of infant mortality, and for estimating the size of some individual cohorts on January 1st of each year.
  3. Deaths
  4. Death counts are collected by sex, completed age, year of birth, and year of death if available. When the distribution of deaths by Lexis triangle is unknown, redistribution by year of birth is done according to the Methods Protocol. Deaths containing missing information on province, sex, year of birth and/or age are redistributed proportionally. For more details, technical papers are available upon request.
  5. Population size
  6. Estimates of population size on January 1st of each year are derived using linear interpolation or the intercensal survival method. Above age 80, population estimates can also be derived by the method of extinct generations or by the survivor ratio method.
  7. Exposure-to-risk
  8. Estimates of the population exposed to the risk of death during some age- time interval are based on annual (January 1st) population estimates, with a small correction that reflects the timing of deaths during the interval.
  9. Death rates
  10. Death rates correspond to the ratio of deaths to exposure-to-risk in matched intervals of age and time. For age and/or time intervals larger than 1, death rates are always found by pooling deaths and exposures first and then dividing the former by the latter.
  11. Life tables
  12. Death rates are converted to probabilities of death by a standard method. Other life table indicators are then calculated based on obtained death rates. A widely known mathematical model of mortality is used at older ages, as explained in the HMD Methods Protocol.

Changes in population coverage

The province of Newfoundland and Labrador was admitted in the Canadian Confederation in 1949. These changes are taken into account and territorial adjustments are considered for life table computations for Canada as a whole.


NOTE: The text above has been adapted from the Human Mortality Database web site (www.mortality.org).