Epidemiology is the study of the distribution of disease among populations. Knowing which population groups have a greater or lesser rate of a disease than expected, leads to knowledge about the risk factors for the condition and suggest ways in which different factors promote or prevent it.

In the case of suicide, rates in different groups are obtained by examining the demographic information that is included on death certificates, by prospective controlled follow-up studies of high-risk groups or by retrospective inquiries about suicide victims and a control group after their death (the psychological autopsy method).

Please note that some of the data presented here are up to four years old. Summary incidence data are usually published after a two-year delay. However, other data are not published and can only be obtained by laborious analysis. However, fluctuations are small and it should be assumed that the data provided below are broadly representative of the current situation.

Incidence:

Child suicide is very uncommon. In 1993:

230 boys and 85 girls aged between 10 and 14 committed suicide in the United States or about 7% of all deaths occurring in this age group. The age-specific mortality rate from suicide was 1.7 per 100,000. Although 10- to 14-year-olds represented 7% of the U.S. population, the 315 child suicides represented only 1% of all suicides.

Most suicides in this group are aged between 12 and 14. Only six children under the age of 10 committed suicide.

Adolescent suicide is more common. In 1993:

1,561 boys and 323 adolescent girls aged 15- to 19-years-old committed suicide, giving a suicide mortality rate of 10.9 per 100,000. This is over six times as common as in the younger age group.

The suicide rate among boys was 17.6 per 100,000 and among girls 3.8 per 100,000.

The proportion of suicides that occur in this age group (13% of the general population) is greater than the proportion of this age group found in the general population (7%).

Young Adult suicide is even more common. In 1993:

2,558 males and 407 females between the ages of 20-24 years old committed suicide, yielding an overall mortality rate of 15.8 per 100,000. This age group represents 7.5% of the total population, but the suicides represent 9% of all suicides.

Age:

The reason why suicide is so rare before puberty is not known. This is a universal phenomenon found in all countries. A likely explanation is that critical risk factors such as depression or exposure to drugs and alcohol are rare in very young children.

Gender:

The ratio of boys to girls is almost equal among 10- to fourteen-year-olds.

In the U.S., nearly 3.6 times as many teen boys commit suicide as girls. The discrepancy is even greater among 20- to twenty-four year-olds, but then diminishes until senescence.

In parts of Asia and Latin America, a majority of suicides are committed by women.

In most countries, suicide attempts are more common among females than among males.

Possible explanations for observed gender differences include:

Differences in type of psychopathology found to be associated with suicidal behavior. Suicide is often associated with aggressive behavior which is more common in males.

Gender differences in the methods favored for suicidal behavior, e.g., overdoses, favored by women, are usually unsuccessful in North America and Western Europe, but are more likely to be successful in Third World countries.

Ethnicity:

Suicide rates among whites are higher than among blacks at all ages, including the teen years.

Difference between black and white rates is greatest in the South and least in the North Central States. (Shaffer et al, 1994).


Possible explanations for the ethnic rate differences include:

Selective under reporting of suicide among different ethnic groups. Studies do not give any support to this explanation.

An artifact of SES, given the strong association between social class and ethnicity. Studies do not give any support to this explanation.

Cultural factors that promote suicide; e.g. Japanese or the Apache Indians. The presence of positive value in the culture could reduce taboos against suicide.

Cultural factors that inhibit suicide. Individuals that regard suicide in a very negative light, even if at risk from character disorders or psychopathology, may be inhibited from committing suicide.

Geography:

In the United States, youth suicide rates, uncorrected for ethnicity, are highest among the Western states and Alaska and lowest in the South, North Central and North Eastern states.

Secular trends:

Over the past two decades, suicide has become less common in the middle-aged and elderly but more common in the young. Figure 3 shows the threefold increase among white males aged between fifteen and twenty-four. The rate for black and other minority males has increased markedly since 1986. There has been no significant change in the suicide rate for either black or white females (Vital Statistics of the United States 1968-1993).

AFSP would like to thank Columbia College of Physicians and Surgeons' Department of Child Psychiatry for allowing the U.S.e of their material on its Web site. AFSP particularly wishes to thank David Shaffer, M.D.,F.R.C.P., F.R.C. Psych, Madelyn Gould, Ph.D., Robin Garfinkel, Ph.D., Laura Mufson, Ph.D., Prudence Fisher, M.S., Holly Wilcox, M.A., and Roger Hicks, B.A., for the information within.

copyright 1998 american foundation for suicide prevention.