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Unintended consequence



 
 
Unintended consequences are outcomes that are not (or not limited to) the results originally intended in a particular situation. The unintended results may be foreseen or unforeseen, but they should be the logical or likely results of the action. For example, historians have speculated that if the Treaty of Versailles
Treaty of Versailles

The Treaty of Versailles was one of the peace treaty at the end of World War I. It ended the declaration of war between German Empire and Allies of World War I....
 had not imposed such harsh conditions on Germany, World War II
World War II

World War II, or the Second World War , was a global military conflict which involved a Participants in World War II, including all of the great powers, organised into two opposing military alliances: the Allies of World War II and the Axis powers....
 would not have occurred. From this perspective, one might consider the war an unintended consequence of the treaty.

Unintended consequences can be grouped into roughly three types:



Discussions of unintended consequences usually refer to the situation of perverse results.






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Unintended consequences are outcomes that are not (or not limited to) the results originally intended in a particular situation. The unintended results may be foreseen or unforeseen, but they should be the logical or likely results of the action. For example, historians have speculated that if the Treaty of Versailles
Treaty of Versailles

The Treaty of Versailles was one of the peace treaty at the end of World War I. It ended the declaration of war between German Empire and Allies of World War I....
 had not imposed such harsh conditions on Germany, World War II
World War II

World War II, or the Second World War , was a global military conflict which involved a Participants in World War II, including all of the great powers, organised into two opposing military alliances: the Allies of World War II and the Axis powers....
 would not have occurred. From this perspective, one might consider the war an unintended consequence of the treaty.

Unintended consequences can be grouped into roughly three types:

  • a positive unexpected benefit, usually referred to as serendipity
    Serendipity

    Serendipity is the effect by which one accidentally discovers something fortunate, especially while looking for something else entirely. The word has been voted as one of the ten English words that were Words hardest to translate in June 2004 by a United Kingdom translation company....
     or a windfall
  • a negative or perverse effect, that may be contrary to what was originally intended
  • a potential source of problems, such as described by Murphy's law
    Murphy's law

    File:Train wreck at Montparnasse 1895.jpgMurphy's law is an adage in Western culture that broadly states: "Anything that can go wrong will go wrong."...


Discussions of unintended consequences usually refer to the situation of perverse results. This situation can arise when a policy has a perverse incentive
Perverse incentive

A perverse incentive is an incentive that has an unintended and undesirable effect, that is against the interest of the incentive makers. Perverse incentives by definition produce negative unintended consequences....
 and causes actions contrary to what is desired.

The law of unintended consequences

The "law of unintended consequences" (also called the "law of unforeseen consequences") states that any purposeful action will produce some unintended consequences. A classic example is a bypass
Bypass (road)

A bypass is a road or highway that avoids or "bypasses" a built-up area, town, or village, to let through traffic flow without interference from local traffic, to reduce congestion in the built-up area, and to improve road safety....
 — a road built to relieve traffic congestion on a congested road — that attracts new development and with it more traffic, resulting in two congested streets instead of one.

This maxim is not a scientific law
Scientific law

A scientific law is a concise verbal or mathematical statement of a relation that is always under the same conditions. Only after numerous experiments by many scientists over an extended period of time can a hypothesis become a scientific law....
; it is more in line with Murphy's law
Murphy's law

File:Train wreck at Montparnasse 1895.jpgMurphy's law is an adage in Western culture that broadly states: "Anything that can go wrong will go wrong."...
 as a warning against the hubris
Hubris

Hubris or hybris , mythology is a term used in modern English to indicate overweening pride, superciliousness, or arrogance, often resulting in fatal retribution....
tic belief that humans can fully control the world around them. Stated in other words, each cause has more than one effect
Effect

Effect, from Latin effectus "performance, accomplishment" can be used in various meanings:* Any result of another action or circumstance ;...
, and these effects will invariably include at least one unforeseen side effect
Side effect

Side effect can mean:* Adverse reaction, an unintended consequence specifically arising from drug therapy* Therapeutic effect, an unintended but desirable consequence of any kind of medical treatment...
. The unintended side effect can potentially be more significant than any of the intended effects.

History

The idea of unintended consequences dates back at least to Adam Smith
Adam Smith

Adam Smith was a Scotland Ethics and a pioneer of political economy. One of the key figures of the Scottish Enlightenment, Smith is the author of The Theory of Moral Sentiments and The Wealth of Nations....
, the Scottish Enlightenment
Scottish Enlightenment

The Scottish Enlightenment was the period in 18th century Scotland characterised by an outpouring of intellectual and scientific accomplishments....
, and consequentialism
Consequentialism

Consequentialism refers to those moral theories which hold that the consequences of a particular action form the basis for any valid moral judgment about that action....
 (judging by results). However, it was the sociologist Robert K. Merton
Robert K. Merton

Robert King Merton was a distinguished American sociologist perhaps best known for having coined the phrase "self-fulfilling prophecy." He also coined many other phrases that have gone into everyday use, such as "role model" and "unintended consequences"....
 who popularized this concept in the twentieth century.

In his 1936 paper, "The Unanticipated Consequences of Purposive Social Action", Merton tried to apply a systematic analysis to the problem of "unanticipated consequences" of "purposive social action". He emphasized that his term "purposive action… [is exclusively] concerned with 'conduct' as distinct from 'behavior.' That is, with action that involves motives and consequently a choice between various alternatives". Merton also stated that "no blanket statement categorically affirming or denying the practical feasibility of all social planning is warranted."

Causes

Possible causes of unintended consequences include the world's inherent complexity
Complexity

In general usage, complexity tends to be used to characterize something with many parts in intricate arrangement. In science there are at this time a number of approaches to characterizing complexity, many of which are reflected in this article....
 (parts of a system responding to changes in the environment), perverse incentive
Perverse incentive

A perverse incentive is an incentive that has an unintended and undesirable effect, that is against the interest of the incentive makers. Perverse incentives by definition produce negative unintended consequences....
s, human stupidity
Stupidity

Stupidity is the Property a person, Action or belief instantiates by virtue of having or being indicative of low intelligence or poor learning abilities....
, self-deception
Self-deception

Self-deception is a process of denial or Rationalization away the relevance, significance, or importance of opposing evidence and logical argument....
 or other cognitive
Cognitive bias

A cognitive bias is a person's tendency to make errors in judgment based on cognitive factors, and is a phenomenon studied in cognitive science and social psychology....
 or emotional
Emotional bias

An emotional bias is a distortion in cognition and decision making due to emotional factors.That is, a person will be usually inclined* to believe something that has a positive emotional effect, that gives a pleasant feeling, even if there is evidence to the contrary....
 biases.

Robert K. Merton
Robert K. Merton

Robert King Merton was a distinguished American sociologist perhaps best known for having coined the phrase "self-fulfilling prophecy." He also coined many other phrases that have gone into everyday use, such as "role model" and "unintended consequences"....
 listed five possible causes of unanticipated consequences:

  1. Ignorance (It is impossible to anticipate everything, thereby leading to incomplete analysis)
  2. Error (Incorrect analysis of the problem or following habits that worked in the past but may not apply to the current situation)
  3. Immediate interest, which may override long-term interests
  4. Basic values may require or prohibit certain actions even if the long-term result might be unfavorable (these long-term consequences may eventually cause changes in basic values)
  5. Self-defeating prophecy
    Self-defeating prophecy

    A self-defeating prophecy is the complementary opposite of a self-fulfilling prophecy: a prediction that prevents what it predicts from happening....
     (Fear of some consequence drives people to find solutions before the problem occurs, thus the non-occurrence of the problem is unanticipated)


Examples


Unexpected benefits

  • The medieval policy of setting up large hunting reserves for the nobility
    Nobility

    Nobility is a government-privileged title which may be either hereditary or for a lifetime. Titles of nobility exist today in many countries although it is usually associated with present or former monarchies....
     has preserved green space, often as park
    Park

    A park is a Environmental protection, in its natural or semi-natural state or planted, and set aside for human recreation and enjoyment....
    s, throughout England
    England

    native_name =|conventional_long_name = England|common_name = England|image_flag = Flag of England.svg|image_coat = England COA.svg|symbol_type = Royal Coat of Arms...
     and other places in Europe
    Europe

    Europe is, conventionally, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally divided from Asia to its east by the water divide of the Ural Mountains, the Ural , the Caspian Sea, and by the Caucasus Mountains to the southeast....
    . Likewise the creation of "no-man's lands" in places such as the Korean Demilitarized Zone
    Korean Demilitarized Zone

    The Korean Demilitarized Zone is a strip of land running across the Korean Peninsula that serves as a buffer zone between North Korea and South Korea Korea....
     have created unique natural habitats. The same has occurred with minefields in the Falkland Islands
    Falkland Islands

    The Falkland Islands are an archipelago in the South Atlantic Ocean, located from the coast of Argentina, west of the Shag Rocks , and north of the British Antarctic Territory ....
    : since birds are too light to trigger the mines, the minefields have become de facto bird sanctuaries.


  • The sinking of ships in shallow waters during wartime has created many artificial coral reefs: beautiful, scientifically valuable and an attraction for recreational divers.


  • Research carried out by John J. Donohue and Steven Levitt
    Steven Levitt

    Steven David "Steve" Levitt is an United States economist known for his work in the field of crime, in particular on the Legalized abortion and crime effect....
     suggests that legalized abortion
    Abortion

    An abortion is the termination of a pregnancy by the removal or expulsion of an embryo or fetus from the uterus, resulting in or caused by its death....
     in the United States can account for much of the drop in crime rates that occurred in the 1990s. States that legalized abortion before Roe v. Wade
    Roe v. Wade

    Roe v. Wade, Case citation , is a Supreme Court of the United States case that resulted in a landmark decision regarding abortion. According to the Roe decision, most laws against abortion in the United States violated a United States Constitution to privacy under the Due Process Clause of the Fourteenth Amendment to the United Stat...
     saw correspondingly earlier drops in crime; and states where abortion is common saw greater drops in crime than states where abortion is rare. Most convincingly, they found that "in high abortion states, only arrests of those born after abortion legalization fall relative to low abortion states."


  • In medicine
    Medicine

    Medicine is the art and science of healing. It encompasses a range of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
    , most drugs
    Medication

    A pharmaceutical drug, also referred to as medicine or medicament, can be loosely defined as any substance intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease....
     have unintended consequences associated with their use, which are known as 'side effect
    Side effect

    Side effect can mean:* Adverse reaction, an unintended consequence specifically arising from drug therapy* Therapeutic effect, an unintended but desirable consequence of any kind of medical treatment...
    s'. Many are harmful and are more precisely called 'adverse effects
    Adverse effect (medicine)

    In medicine, an adverse effect is a harmful and undesired effect resulting from a medication or other intervention such as chemotherapy or surgery....
    '. However, some are beneficial—for instance, aspirin
    Aspirin

    Aspirin , also known as acetylsalicylic acid , is a salicylate medication, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication....
    , a pain reliever, can also thin the blood and help to prevent heart attacks
    Myocardial infarction

    Myocardial infarction , commonly known as a heart attack, occurs when the Blood flow to part of the heart is interrupted. This is most commonly due to occlusion of a coronary artery following the rupture of a Vulnerable plaque, which is an unstable collection of lipids and white blood cells in the wall of an artery....
    . The existence of beneficial side effects also leads to off label use — prescription or use of a drug for a non-intended purpose.


Perverse results

  • The Streisand Effect
    Streisand effect

    The Streisand effect is a Internet phenomenon where an attempt to Censorship or remove a piece of information backfires, causing the information to be widely publicized....
     occurs when an attempt to censor or remove a certain piece of information (such as a photograph, document, etc.) instead causes the information to become widely known and distributed. The fact that a piece of information is being restricted assigns to it a previously nonexistent value in the eyes of the public.


  • The introduction of rabbit
    Rabbits in Australia

    File:Oryctolagus cuniculus Tasmania.jpgFile:Wild rabbit in grass.jpgIn Australia, rabbits are the most serious mammalian Pest , an invasive species whose destruction of habitats is responsible for the extinction or major decline of many native animals such as the Western Quoll....
    s into Australia
    Australia

    Australia, officially the Commonwealth of Australia, is a country in the southern hemisphere comprising the Australia of the world's smallest continent, the major island of Tasmania, and numerous list of islands of Australia in the Indian Ocean and Pacific Oceans....
     for sport led to an explosive growth in the rabbit population; rabbits have become a major feral
    Feral

    A feral organism is one that has escaped from domestication and returned, partly or wholly, to its wildlife state. The introduction of feral animals or plants, like any introduced species, can disrupt ecosystems and may, in some cases, contribute to extinction of indigenous species....
     pest
    Pest (animal)

    A pest is an organism which has characteristics that are regarded by humans as injurious or unwanted. This is most often because it causes damage to agriculture through feeding on crops or parasitising livestock, such as codling moth on apples, or boll weevil on cotton....
     in Australia. The same has occurred in New Zealand
    New Zealand

    New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses , and numerous Islands of New Zealand, most notably Stewart Island/Rakiura and the Chatham Islands....
    .


  • Along the same lines, kudzu
    Kudzu

    , Pueraria lobata , is one of about 20 species in the genus Pueraria in the pea family Fabaceae, subfamily Faboideae. It is native to southern Japan and southeast China in eastern Asia....
     has become a major problem in the South Eastern United States since its introduction as a way of preventing erosion in earthworks. Kudzu has displaced native plants, and has effectively taken over significant portions of land.


  • The stiffening of penalties for driving while intoxicated in the United States in the 1980s led, at first, to an increase in hit and run accidents
    Hit and run (vehicular)

    Hit-and-run is the crime of Collision with a person, their personal property , or a fixture , and failing to stop and identify oneself afterwards....
    , most of which were believed to have been drunken drivers trying to escape the law. Legislators later stiffened penalties for leaving the scene of an accident.


  • In 1990, the State of Victoria (Australia)
    Victoria (Australia)

    File:Map Victoria Aboriginal tribes .jpgVictoria is a States and territories of Australia located in the southeastern corner of Australia. It is the smallest mainland state in area but the most Population density and urbanised....
     made safety helmets
    Bicycle helmet

    A bicycle helmet is a helmet intended to be worn while riding a bicycle. They are designed to attenuate impacts to the cranium of a cyclist in falls while minimizing side effects such as interference with peripheral vision....
     mandatory for all bicycle riders. Together with a reduction in the absolute number of head injuries, there was also an unexpected reduction in the number of juvenile cyclists. Research by Vulcan et al. found that the reduction in juvenile cyclists was because the youths considered wearing a bicycle helmet unfashionable.


  • Prohibition
    Prohibition

    Prohibition of alcohol, often referred to simply as prohibition, also known as The Noble Experiment, refers to a sumptuary law which prohibits alcohol....
     in the 1920s U.S., originally enacted to suppress the alcohol trade, drove many small-time alcohol suppliers out of business and consolidated the hold of large-scale organized crime
    Organized crime

    Organized crime or criminal organizations comprise groups or operations run by crimes, most commonly for the purpose of generating a money profit....
     over the illegal alcohol industry. Since alcohol was still popular, criminal organisations producing alcohol were well funded and hence also increased their other activities. The War on Drugs
    War on Drugs

    The War on Drugs is a controversial prohibition campaign undertaken by the United States government with the assistance of participating countries, intended to reduce the illegal drug trade?to curb supply and diminish demand for specific psychoactive substances deemed immoral, harmful, dangerous, or undesirable....
    , intended to suppress the illegal drug trade, has likewise consolidated the hold of organized drug cartels over the illegal drug industry.


  • In CIA jargon
    Jargon

    Jargon is terminology which has been especially defined in relationship to a specific activity, profession, or group. In other words, the term covers the language used by people who work in a particular area or who have a common interest....
    , "blowback
    Blowback (intelligence)

    Blowback is the espionage term for the violent, unintended consequences of a covert operation that are suffered by the civil population of the aggressor government....
    " describes the unintended, undesirable consequences of covert operations. Examples include:
    • Operation Ajax
      Operation Ajax

      The 1953 Iranian Coup d??tat was the Western covert operation that deposed the democratically-elected Government of Prime Minister Mohammed Mosaddeq; the CIA and MI6 effected it by aiding and abetting pro-West Iranians and mutinous Iranian army officers....
      , which contributed to the 1979 Iranian Revolution
      Iranian Revolution

      The Iranian Revolution was the revolution that transformed Iran from a Iranian monarchy under Shah Mohammad Reza Pahlavi to an Islamic republic under Ayatollah Ruhollah Khomeini, the leader of the revolution and founder of the Islamic Republic....
       & the Iran hostage crisis
      Iran hostage crisis

      The Iran hostage crisis was a diplomacy crisis between Iran and the United States where 52 U.S. diplomats were held hostage for 444 days from November 4, 1979 to January 20, 1981, after a group of Islamism students took over the American embassy in support of the Iranian revolution....
    • Covert funding of the Mujahideen
      Mujahideen

      A Mujahid is a person involved in a jihad. The plural is Mujahideen . The word is from the same Arabic triliteral as jihad ....
      , which led to the rise of the Taliban


  • Rent control
    Rent control

    Rent control refers to laws or ordinances that set price controls on the renting of residential housing. It functions as a price ceiling....
     leads in the long run to housing shortages, and drops in housing availability and quality. It may even lead to the creation of slum
    Slum

    A slum, as defined by the United Nations agency UN-HABITAT, is a run-down area of a city characterized by substandard housing and squalor and lacking in tenure security....
     areas where owners permit rental property to run down until it becomes uninhabitable.


  • Father Mathew's temperance campaign in 19th-century Ireland
    Ireland

    Ireland is the List of islands by area in Europe, and the twentieth-largest island in the world. It lies to the north-west of continental Europe and is surrounded by hundreds of islands and islet....
     – in which thousands of people vowed never to drink alcohol
    Ethanol

    Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatility , flammable, colorless liquid....
     again – led to the consumption of ether
    Diethyl ether

    Diethyl ether, also known as ether and ethoxyethane, is a clear, colorless, and highly flammable liquid with a low boiling point and a characteristic odor....
    , a much more dangerous intoxicant, by those unwilling to break their pledge.


Failure mode and effects analysis

Failure mode and effects analysis
Failure mode and effects analysis

A failure modes and effects analysis is a procedure for analysis of potential failure modes within a system for classification by severity or determination of the effect of failures on the system....
 (FMEA) is a fault tree method (first developed for systems engineering
Systems engineering

Systems engineering is an interdisciplinary field of engineering that focuses on how complex engineering projects should be designed and managed....
) that examines potential failures in products or processes. It may be used to evaluate risk management
Risk management

Risk management is activity directed towards the assessing, mitigating and monitoring of risks. In some cases the acceptable risk may be near zero....
 priorities for mitigating known threat-vulnerabilities.

FMEA helps select remedial actions that reduce cumulative impacts of life-cycle consequences (risks) from a systems failure (fault).

Purposeful gaming to achieve unintended consequences

Another more restrictive use of the term unintended consequence is when a mechanism that has been installed with the intention of producing one result is used to produce a different (and often conflicting) result. One games the system
Gaming the system

Gaming the system means using the rules, policies and procedures of a system against itself for purposes outside what these rules were intended for....
 when one acts in such a way that gains advantages by exploiting rules which were intended for some other purpose. For example, computer viruses, worms, and other such plagues are unintended consequences of the way certain computer systems are designed. Spam is an unintended consequence of the way the email system works. The preceding computer examples illustrate this sense of unintended consequence in that spammers hijack a mechanism, e.g., email, intended for interpersonal communication, for advertising.

This sense of unintended consequence excludes, for example, the proliferation of rabbits in Australia as an unintended consequence of their introduction. The proliferation of rabbits was indeed an unexpected (and unintended) consequence of their introduction, but it did not result from the exploitation of a mechanism for some other purpose. The intent to "game the system" distinguishes this interpretation of unintended consequence from such a broader interpretation of unintended consequence as a result of simple historical contingency. See the for more examples.

See also

  • Conflict of interest
    Conflict of interest

    A conflict of interest occurs when an individual or organization has an interest that might compromise their reliability. A conflict of interest exists even if no improper act results from it, and can create an appearance of impropriety that can undermine confidence in the conflicted individual or organization....
  • Counter-intuitive
  • Externality
    Externality

    In economics, an externality or spillover is a positive or negative impact on a party not directly involved in an economic transaction. In such a case, prices do not reflect the full costs or benefits in production or consumption of a product or service....
  • Futures techniques
    Futures techniques

    In the multi-disciplinary field of futurology, futurologists use a diverse range of forecasting methods, including:...
  • Hawthorne effect
    Hawthorne effect

    The Hawthorne effect is a form of reactivity ,The term was coined in 1955 by Henry A. Landsberger when analyzing older experiments from 1924-1932 at the Hawthorne Works ....
  • Herostratus
    Herostratus

    Herostratus was a young man who set fire to the Temple of Artemis at Ephesus in his quest for celebrity on about July 20, 356 BC. The Greek temple was constructed of marble and considered the most beautiful of some thirty shrines built by the Greeks to honour their goddess of the hunt, the wild and childbirth....
  • Hutber's law
    Hutber's law

    Hutber's law states that "improvement means deterioration". It is founded on the cynical observation that a stated improvement actually hides a deterioration....
  • Invasive species
    Invasive species

    Invasive species is a phrase with several definitions. The first definition expresses the phrase in terms of non-indigenous species that adversely affect the habitats they invade economically, environmentally or ecologically....
  • Inverse consequences
    Inverse consequences

    The term "inverse consequences" or the "Law of Inverse Consequences" refers to results that are the opposite of the expected results as initially intended or planned....
  • Kludge
    Kludge

    A kludge is a workaround, an ad hoc engineering solution, a clumsy or inelegant solution to a problem, typically using parts that are cobbled together....
  • Moral hazard
    Moral hazard

    Moral hazard is the prospect that a party insulated from risk may behave differently from the way it would behave if it were fully exposed to the risk....
  • Nocebo
    Nocebo

    In its original application, "nocebo" had a very specific meaning in the medical domains of pharmacology, and nosology, and etiology.It was a subject-oriented adjective that was used to label the harmful, unpleasant, or undesirable reactions that a subject manifested as a result of administering an inert placebo, where these responses had...
  • Parable of the broken window
    Parable of the broken window

    The parable of the broken window was created by Fr?d?ric Bastiat in his 1850 essay to illuminate the notion of hidden costs.Bastiat uses this story to introduce a concept he calls the broken window fallacy, which is related to the Unintended consequences, in that both involve an incomplete accounting for the consequences of an a...
  • Perverse effects of vaccination
    Perverse effects of vaccination

    Perverse effects of vaccination occur when a vaccination program causes more harm than it cures. This can happen if too few are vaccinated, allowing the disease to spread, albeit more slowly than in an unvaccinated population....
  • Placebo
    Placebo

    The placebo effect is a phenomenon in medicine where the results of a medical treatment are affected by their symbolism, and not just their medical value....
  • Regression testing
    Regression testing

    Regression testing is any type of software testing which seeks to uncover Software regression. Such regressions occur whenever software functionality that was previously working correctly stops working as intended....
  • "Superiority
    Superiority (short story)

    "Superiority" is a science fiction short story by Arthur C. Clarke, first published in 1951 in literature. It depicts an arms race, and shows how the side which is more technologically advanced can be defeated, despite its apparent superiority, because of its own organizational flaws and its willingness to use new technologies without fully u...
    "


External links

  • by Robert K. Merton, American Sociological Review, Vol 1 Issue 6, Dec 1936, pp.894-904
  • Edward Tenner, Why Things Bite Back: Technology and the Revenge of Unintended Consequences, Vantage Books, 1997.
  • Tomislav V. Kovandzic, John Sloan III, and Lynne M. Vieraitis. Unintended Consequences of Politically Popular Sentencing Policy: The Homicide-Promoting Effects of 'Three Strikes' in U.S. Cities (1980-1999). Criminology & Public Policy, Vol 1, Issue 3, July 2002.
  • Vulcan, A.P., Cameron, M.H. & Heiman, L., "Evaluation of mandatory bicycle helmet use in Victoria, Australia", 36th Annual Conference Proceedings, Association for the Advancement of Automotive Medicine, Oct 5-7, 1992.
  • Vulcan, A.P., Cameron, M.H. & Watson, W.L., "Mandatory Bicycle Helmet Use: Experience in Victoria, Australia", World Journal of Surgery, Vol.16, No.3, (May/June 1992), pp.389-397.