Mental health

Poor mental health may be more common in gangs

"Gang violence cause of high levels of mental disorders," reports BBC online. This headline comes from a study that surveyed more than 4,500 young men in Britain. More than a quarter of these men reported being violent but were not involved in gangs, while 108 (about 2%) reported being gang members.

Researchers found that regardless of gang involvement, a history of violence was strongly associated with a higher risk of mental illness. But the risk of developing some types of mental health conditions was significantly higher in gang members. These conditions include:

Analyses suggest that in gang members, this increase in risk could be related to dwelling on violent thoughts, having experienced violent victimisation and fear of further victimisation.

But a major drawback of this study is that it did not determine whether the men had a psychiatric diagnosis before they joined a gang, or if their mental health problems developed afterwards.

As the study was a survey, it also could not carry out the in-depth interviews required to give formal diagnoses.

Despite these limitations, these results provide an insight into a complex problem that needs to be tackled.

Where did the story come from?

The study was carried out by researchers from Queen Mary, University of London. It was funded by the Maurice and Jacqueline Bennett Charitable Trust and the UK National Institute for Health Research.

It was published in the peer-reviewed American Journal of Psychiatry.

Both the BBC and The Independent's coverage of the study was well balanced and accurate.

What kind of research was this?

This was a cross-sectional study looking at how common psychiatric disorders are among men in Britain, including men who are members of gangs. The researchers suggest that through violence, gang members may be exposed to multiple risk factors for developing psychiatric problems.

This type of study is good for identifying how common a particular condition is in a group of people. But as it only assesses people at one point in time, it cannot determine which of the characteristics came first. For example, in this study, the researchers were not able to tell whether the men had psychiatric diagnoses before they joined a gang or if their conditions developed afterwards.

What did the research involve?

The study recruited 4,664 men aged 18-34 to take part in a survey. The men were asked questions about their gang membership, violence and use of mental health services, and were also assessed for psychiatric diagnoses. 

Researchers then looked at whether psychiatric diagnoses were more common in men who were members of gangs or engaged in violence.

The researchers selected locations at random to obtain a representative sample of men aged 18-34. They also specifically selected young black and ethnic minority men from these regions, as well as men from lower social classes.

Additional locations where there were high levels of violence and gang activities (Hackney and East Glasgow) were also selected to ensure that a reasonable number of male gang members were assessed.

The questionnaires included a screening questionnaire for psychosis. Questions were also taken from standard interviews to identify antisocial personality disorder, anxiety and depression. Participants were asked:

  • whether they had ever tried to kill themselves
  • about current medications for psychiatric conditions
  • about consultations with a medical practitioner in the last year for a mental health problem
  • whether they had ever seen a psychiatrist or psychologist
  • if they had been admitted to a psychiatric hospital
  • about any violent behaviour and the number of violent incidents they had been involved in
  • about their attitudes to and experiences of violence
  • whether they were currently a member of a gang

As well as self-reporting gang membership, participants had to report at least one of the following to be included as a "gang member" in the analysis:

  • involvement in serious criminal activities or convictions
  • involvement in criminal activities with friends  
  • involvement in gang fights during the past five years

Based on their answers, men were divided into three groups:

  • non-violent men – participants reporting no violent behaviour over the past five years and no gang membership
  • violent men – participants reporting violence over the past five years, but no gang membership or involvement in gang fights
  • gang member

The researchers compared characteristics and psychiatric diagnoses in these three groups, taking into account factors that could influence the results (confounders), such as unemployment, ethnicity, age and other factors.

They also used statistical methods to analyse whether any associations could be statistically explained by attitudes toward violence, victimisation experiences and characteristics of violent behaviours.

What were the basic results?

Of the 4,664 men surveyed:

  • 70% (3,285 men) were classed as non-violent
  • 27.3% (1,272 men) were classed as violent, but were not gang members
  • 2.1% (108 men) reported current gang membership

The researchers found that psychosis, anxiety, alcohol dependence and antisocial personality disorder were more common in violent men and gang members than in non-violent men.

Violent men and gang members were more likely to have attempted suicide than non-violent men. Violent men and gang members were also found to use psychiatric services more regularly than non-violent men.

But men who were violent or who were gang members were less likely to experience depression than non-violent men.

Gang members were more likely to have alcohol dependence, drug dependence, or antisocial personality disorder. They were also more likely to have attempted suicide than violent men who were not part of gangs.

Gang members were also more likely than non-violent men to dwell on violent thoughts (violent ruminative thinking), have experienced violent victimisation, and fear further victimisation.

Statistical analysis suggested that these factors could account for the higher levels of psychosis and anxiety disorders seen in gang members.

How did the researchers interpret the results?

The researchers concluded that gang members show "inordinately high levels of psychiatric morbidity, placing a heavy burden on mental health services".

They advise that gang membership "should be routinely assessed in individuals presenting to healthcare services in areas with high levels of violence and gang activity".


This study has found that psychiatric conditions are common among male gang members and violent men. There are, however, several important points to note:

  • This type of study only assessed the men at one point in time, so it cannot determine whether the men had a psychiatric diagnosis before they joined a gang, if they were exposed to or committed violence, or if their mental health condition developed afterwards.
  • Men who agreed to take part in the survey may differ in characteristics to those who did not (a form of selection bias). It was not clear exactly what proportion of the men who were asked to participate did so.
  • The survey involved young men aged 18-34 and the results may not be representative of younger or older men.
  • The questionnaires used to identify psychiatric problems are accepted questionnaires, but they are not the full psychiatric interviews needed to give a formal clinical diagnosis.
  • The questionnaires were based on self-reporting and did not use more objective measures, such as an assessment of criminal records. There may therefore be some misreporting.
  • As the authors note, there is no consensus on the definition of "gang membership", so they used three out of five criteria from the UK criminal justice agency that could be used in a questionnaire format.

As the authors note, the study highlights "a complex public health problem at the intersection of violence, substance misuse and mental health problems among young men".

They suggest that further research is needed to identify effective interventions for gang members with these problems.

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