Facets of Medicine (2)


By William Wetherall

A Japanese version of this article appeared in
Kokutai, 16(4), May 1995, pages 160-161

Two wise men are constantly challenging one another. One day, after lunch, the first wise man says "Let's see who can count the highest." The second says "Okay, you go first," and the first says "One." That evening, during dinner, the second wise man says "Two." Over tea the next morning, the first wise man, weary eyed, says "Three." Days later, the second wise man, several kilos lighter, says "You win."

The leap from one, two, three to infinity, and the discovery of zero and imaginary numbers, are landmarks on the long trail from early counting to modern number theory. Today's wise men are mathematicians and computer programmers who challenge each other to discover new prime numbers, or see to how many places they can compute the value of pi.

Since antiquity, numbers have played a central role in human life, and census takers and other bureaucrats have been the world's principal bean counters. Whole civilizations have been built, and destroyed, by people who have been able to count higher, and in more complicated ways, than others. At the elbow of every Caesar and general obsessed with counting connected and severed heads in their empire or army, there is bound to be a gaggle of petty officials with tally sheets.

Thus bureaucrats are also wise men of sorts, judging from the way they love to count things, and the self-importance they impute to their tallies. Indeed, bureaucrats learned to categorize and count the living and the dead long before social scientists appeared on the stage of life to statistically prove such momentous observations that nearly half of all married people are women, that heavy people are apt to weigh more than light people, and that nine out of ten people eat.

Bureaucrats are almost as old on the evolutionary ladder of life as cockroaches, and they are nearly as synonymous with uncountable and countless. While less at home than roaches in the world's kitchens, government officials are arguably more symbiotic with civilization.

During the Korean War, when a boy breaking into his teens, I read everyday on the front pages of San Francisco newspapers how many US and enemy planes had been shot down. The numbers on the board in my mind showed that the US was scoring far more goals-so why did the game end in a draw that is still being disputed at Panmunjom? Numerically, US forces did even more damage in Vietnam, the war the politicians decided my generation should fight-and in the end that game went to the enemy.

For several days leading up to Emperor Meiji's demise, his vital signs were featured on the front pages of newspapers like a weather report. During the last months of Emperor Showa's life, the sanguine details of his clinical chart were summarized in mass media like stock market volume and averages-up one day, down the next.

Tallies of people killed, injured, and left without homes in the Hanshin Earthquake were updated many times a day on television and in other media for several weeks after the quake. The earliest tallies of deaths were counts of bodies reported to the police soon after discovery at sites of death. Yet even after bodies were no longer being found at sites of death, the number of dead continued to rise, jumping by tens, even hundreds a day-on account of late reports of deaths in which bodies had been disposed of without a police-supervised postmortem.

The earthquake was a splendid opportunity for people who had been contemplating disappearing to just walk away-and leave people thinking that they had been burned beyond recognition or buried beyond recovery. And who knows how many people took advantage of the warlike confusion to commit the perfect murder? There are secrets even the dead cannot tell.

Officials count bodies, living and dead. They call the number of people who are alive at a given time "population", and the number of people who die during a given period "number of deaths". They divide number of deaths by population, multiply by 100,000, and call this the death rate or total mortality for the population during the period.

Epidemiologists, who specialize in studies of incidents of disease and rates of death from various causes, know what to do with the raw counts. They also know that an increase in the number of deaths from year to year does not necessarily mean an increase in the death rate. If the number of people alive each year rises faster than the number of people who die, then the general death rate will fall even though the number of postmortems, funerals, and burials are increasing.

Bureaucrats are supposed to be understand such basic principles of statistics, yet some bureaucracies have traditionally misled the public through numbers. And their traditions of misuse and abuse of statistics have been aided and abetted by the press and other mass media, where innumeracy is as rampant as in the less number-wise halls of government.

Take, for example, the National Police Agency, which regularly releases, through its press club, statistical reports on everything from traffic accidents and juvenile delinquency to adult crime and suicide.

Police are required to determine cause of death when someone has died under equivocal conditions-which means practically all situations in which the deceased was not under the care of a physician who is able to certify that the cause of death was due to a diagnosed illness.

One byproduct of such police work is suicide statistics-since the police must clarify the cause of death in all cases in which death seems to have resulted from an external cause-accident, suicide, or homicide.

The National Police Agency collects such statistics from all the prefectural police headquarters, and then reports to the public every spring the previous year's suicide counts. In 1984, for example, the NPA reported that during 1983, some 25,202 people committed suicide. The report also said that this count had set a new record since the collection of such data had begun during the Meiji period, and it called the count "the highest on record after the war".

In 1987, NPA reported that the 1986 suicide case count was 25,524. This, too, was characterized as being "the highest on record after the war." Yomiuri, Asahi, and most other major media changed the "highest" to "worst", reflecting the spirit in which NPA released and commented on the statistics at its press club. The English language papers similarly reported that Japan's 1986 suicide count was the "highest" or "worst" in postwar history.

While both the 1983 and 1986 suicide counts exceeded the 1958 record high, the greater number of deaths by suicide actually meant lower suicide rates. The 1986 suicide count, for example, was 8.9 percent higher than the 1958 count. But then the 1986 population was 31.4 percent larger than the 1958 population. Hence the crude 1986 suicide rate was 21.2 suicides per 100,000, compared with 25.7 for 1958.

When the 1935 population is used as a reference point, and the 1958 and 1986 suicide rates are recomputed on the basis of the 1935 age and sex composition, the 1958 rate becomes 23.5 and the 1986 rate only 14.5. The differences between these adjusted rates and the crude rates are almost entirely due to population aging. And most of the aging has taken place since 1958.

The way in which the suicide counts for the elderly are reported is even more indicative of the innumeracy that biases impressions of social issues. In 1984, based on NPA data and interpretations, Yomiuri reported that in 1983 some 5,572 people of ages 60 years and older killed themselves, compared to 4,891 five years early in 1978. Yomiuri called these the "worst figures since the war", and then it described Japanese society as one in which "the 'locus of disease' of a 'human feeling paper balloon' is spreading through both families and society." While true that suicides for the 65+ age groups increased in the observed five year period, the population of elderly increased at a greater rate, from 9,921,000 to 11,672,000, which means that the crude suicide rate for the elderly actually fell from 49.3 in 1978 to 47.7 in 1983. When these crude 65+ rates are adjusted to the 1935 population, it becomes clear that elderly suicide risk has fallen even more.

Hence there was no statistical basis for characterizing Japan as a country where the family and social environment have been worsening, much less grounds for blaming the alleged deterioration on family nuclearization and other "American" influences on postwar attitudes toward the elderly.

Not only were prewar conditions for the elderly worse than today, as measured by suicide rates-but numerous current studies suggest that elderly people living with their children are at greater risk than those living independently. As a legacy of prewar social ideology, the ideal of the three generation continues to bias the popular image of elderly suicide in Japan.

The National Police Agency, of course, is not in the business of studying suicide statistics with the object of shedding light on social issues. The primary purpose of NPA statistics, including those it reports for crime and traffic accidents, is to show how much work the police do-which then justifies requests for larger budgets.

While body counts may have meaning as body counts, more bodies do not automatically translate into greater social pathology. While saying "Gokurosama" to the police for their postmortem work, NPA needs to be scolded for the way its public reports mislead the press and even academia. And journalists and scholars who take NPA and other figures at face value need to be sent back to school to study basic statistics.