Print version ISSN 0042-9686
Bull World Health Organ vol.84 n.3 Genebra Mar. 2006
Mexico's quest for a complete mortality data set
On 1 November cemeteries across Mexico are packed with the living. Death has a special place in Mexican culture, especially on the Day of the Dead El Día de los Muertos. But while a culture that accepts death may smooth the task of collecting mortality data, poverty is a major obstacle for Mexico in its quest for a complete data set.
Mexico has been recording deaths in registers for more than 100 years, but it was not until the 1950s that the country developed a death certificate system.
"There are two moments when people die [on paper]," says Dr Rafael Lozano, General Director of Information at the Mexican Ministry of Health. "One is the certification of the death and the second is the registration. Before 1950 we only registered death without certification."
Certification means that a doctor examines the deceased and determines the cause of death. With registry, a person was often listed as dead, but without a cause of death, Lozano says: "So we have a long history with problems of quality before 1950, and also problems of quantity."
About 500 000 out of a population of 103 million die every year. Since the 1980s, more than 90% of the dead have been counted due to this switch to a death certification system. In the '50s, '60s and '70s mortality data was only 70% or 80% complete. In the WHO European Region coverage is about 100%, while in the WHO African Region it is less than 10%.
To help WHO's 35 Member States in the Americas improve their mortality data, the Pan American Health Organization (PAHO) launched the Regional Core Health Data and Country Profile Initiative in 1995.
Dr Roberto Becker, Regional Advisor on Diseases Classification at PAHO in Washington, DC, explains that although most deaths are logged with a civil registry, the cause of death recorded in the certification process is often missing. As part of the 1995 initiative, Becker travels to the countries in PAHO's region to teach health officials how to improve coverage in quality data.
"We don't have 100% coverage. But we are very close," Lozano says, citing a study published in the Bulletin [2005:83;171 77] that ranks Mexico among 23 countries with high quality data and 90% or more complete death registration. Venezuela was also in that group while the rest of the PAHO region had lower coverage.
Since 1950, Mexico has used the WHO-recommended death certification system to fall in line with international standards. This allowed comparison with other countries following the same protocol. Initially, another government agency did the counting. In 1985 that task was moved to Lozano's office.
Having established more accurate ways of determining the numbers and causes of death, Lozano says, the challenge today is to increase coverage.
Current efforts are focused on rural areas where poverty and inadequate infrastructure are major obstacles. "Our main problem is infant mortality," Lozano says. "We have problems with statistics ... when a child is born and when a child dies."
Counting the dead is crucial for a number of reasons.
"To count the deaths according to the cause and ages gives you an idea of what's going on with the population and how you can develop health priorities for intervention programmes to reduce deaths in those areas," says John Silvi, a statistician at PAHO. "For instance in Mexico, diabetes is an extremely important cause of death."
Lozano explains that Mexican health officials use these data to allocate resources and to manage health-care programmes. For instance, in one programme in Mexico, a formula is used to allocate some of the funding, and mortality is one of the variables. In addition, the Ministry of Health can study the data to check for epidemics and other health problems.
Each of Mexico's 32 states, too, uses its mortality figures to set priorities for health policy, and the data are also used during Mexico's annual Health Week. "Deaths are part of the calculations that almost everybody uses," Lozano says, "and not just in the public health sector, but also in the private sector."
When someone dies, the family usually notifies health officials. A doctor will certify the death, determine the cause and give the family the certificate. That's easy enough if the person dies in a hospital or nursing home.
"If not, it's more difficult because you have to call a private doctor," Lozano says. The doctor may charge 500 pesos, which is about US$ 45, and most poor families can't afford that, but the Ministry of Health can't prohibit doctors from charging. "It's a problem for rural areas or very poor families," Lozano says.
Next the family calls the funeral parlour, which fetches the body, and that starts the process of administrative registry. A relative must then go to the office of civil registration and exchange the certificate for the "acta de defunción." The acta is the only one of the two that is legally valid.
The certificate, meanwhile, goes to the Ministry of Health. One copy goes to Mexico's National Institute of Statistics and Geographical Information (INEGI) and the other stays in the civil registry office. The Ministry of Health's forms are coded monthly by doctors assigned for just that purpose according to International Classification of Disease rules, and for its part, INEGI compiles monthly statistics.
Later on, Ministry of Health officials classify the data by cause of death and other factors, Lozano says.
Two types of families don't report: those who can not afford to call a doctor and those who live too far away from an administrative centre.
"This lack of reporting is most frequent in a rural environment," says Lozano, adding that the Ministry of Health can not force people by law to report.
Mexico's Ministry of Health has tried to educate people in hospitals and other facilities in some parts of the country about the need to report every death. Lozano says that the non-reporters represent a small number of people and that, overall, figures are accurate.
Mexico's mortality data has, among other things, helped to highlight the gaping disparities between poor and affluent in this middle-income country.
Although average life expectancy in Mexico is 75 years for men and 77 for women, there is a wide range of disparity between rich and poor. For adults the main causes of death tend to be chronic diseases, such as diabetes, heart disease and stroke. For children pneumonia is still a leading cause of death, while perinatal problems are a big killer of newborns.
"The problem ... is the gaps within the country," Lozano says. "The difference [in life expectancy] between the poorest and the richest states in Mexico is something like 11 years."