Mortality rate



Mortality rate is a measure of the number of deaths (in general, or due to a specific cause) in some population, scaled to the size of that population, per unit time. Mortality rate is typically expressed in units of deaths per 1000 individuals per year; thus, a mortality rate of 9.5 in a population of 100,000 would mean 950 deaths per year in that entire population. It is distinct from morbidity rate, which refers to the number of individuals who have contracted a disease during a given time period (the incidence rate) or the number who currently have that disease (the prevalence rate), scaled to the size of the population.

One distinguishes:
 * 1) The crude death rate, the total number of deaths per 1000 people.
 * 2) The perinatal mortality rate, the sum of neonatal deaths and fetal deaths (stillbirths) per 1,000 births.
 * 3) The maternal mortality rate, the number of maternal deaths due to childbearing per 100,000 live births.
 * 4) The infant mortality rate, the number of deaths of children less than 1 year old per thousand live births.
 * 5) The child mortality rate, the number of deaths of children less than 5 year old per thousand live births.
 * 6) The standardised mortality rate (SMR) or age-specific mortality rate (ASMR) - This refers to the total number of deaths per 1000 people of a given age (e.g. 16-65 or 65+).

In regard to the success or failure of medical treatment or procedures, one would also distinguish:
 * 1) The early mortality rate, the total number of deaths in the early stages of an ongoing treatment, or in the period immediately following an acute treatment.
 * 2) The late mortality rate, the total number of deaths in the late stages of an ongoing treatment, or a significant length of time after an acute treatment.

Note that the crude death rate as defined above and applied to a whole population of people can give a misleading impression. For example, the number of deaths per 1000 people can be higher for developed nations than in less-developed countries, despite standards of health being better in developed countries. This is because developed countries have relatively more older people, who are more likely to die in a given year, so that the overall mortality rate can be higher even if the mortality rate at any given age is lower. A more complete picture of mortality is given by a life table which summarises mortality separately at each age. A life table is necessary to give a good estimate of life expectancy.

Statistics
The ten countries with the highest infant mortality rate are:
 * 1) Angola 	192.50
 * 2) Afghanistan 	165.96
 * 3) Sierra Leone 	145.24
 * 4) Mozambique 	137.08
 * 5) Liberia 	130.51
 * 6) Niger 	       122.66
 * 7) Somalia 	118.52
 * 8) Mali 	       117.99
 * 9) Tajikistan 	112.10
 * 10) Guinea-Bissau 	108.72

According to the World Health Organisation, the 10 leading causes of death in 2002 were:


 * 1) 12.6% Ischaemic heart disease
 * 2)  9.7% Cerebrovascular disease
 * 3)  6.8% Lower respiratory infections
 * 4)  4.9% HIV/AIDS
 * 5)  4.8% Chronic obstructive pulmonary disease
 * 6)  3.2% Diarrhoeal diseases
 * 7)  2.7% Tuberculosis
 * 8)  2.2% Malaria
 * 9)  2.2% Trachea/bronchus/lung cancers
 * 10)  2.1% Road traffic accidents

Causes of death vary greatly between developed and developing countries. See List of causes of death by rate for worldwide statistics.

Factors affecting a country's death rate

 * Age of country's population
 * Nutrition levels
 * Standards of diet and housing
 * Access to clean drinking water
 * Hygiene levels
 * Levels of infectious diseases
 * Levels of violent crime
 * Conflicts
 * Number of doctors

Sources and references

 * CIA World Factbook -- Rank Order - Death rate
 * Mortality - The Medical Dictionary by Medterms
 * "10 Leading Causes of Death, United States" from the Center for Disease Control
 * Edmond Halley, An Estimate of the Degrees of the Mortality of Mankind (1693).