A large study in Wales finds a strong connection between school absence and exclusion, and self-harm and ill mental health in children

The Researchers
Professor Ann John
Professor Ann John

Principal Investigator

Dr Yasmin Friedmann
Dr Yasmin Friedmann

Senior Research Data Scientist

Children with poor mental health, who are neurodiverse or who self-harm often struggle at school. Health and educational professionals, services, and policy makers should be aware that children with poor attendance may be experiencing emotional ill-health whether this is diagnosed in school or into early adulthood.

Professor Ann John
Principal Investigator

The Problem

Poor school attendance is associated with a range of negative outcomes across the life course, including poor educational attainment, unemployment, and poverty. Pupils with mental health and neurodevelopmental disorders (e.g., ADHD, autism) or who self-harm are more likely to miss school through absenteeism and exclusion than their classmates. Currently rates of exclusion in England are rising, highlighting the importance of school-based policies aiming to improve behaviour and support teachers.

The Research

The team linked routinely collected and de-identified educational data to demographic, primary and secondary health care datasets, creating a population-wide cohort of 437,412 pupils aged 7-16 between 2009 and 2013 in Wales. They also identified a wide range of clinically diagnosed and recorded mental disorders up to the age of 24, including presentations with self-harming behaviours.

The Outcomes

  • The team found that pupils who self-harm or have a mental health condition are more likely to miss school because of being excluded or due to absence. This is true but to a slightly lesser extent for pupils who also have a special educational needs (SEN) status.
  • Rates of absences are higher for older children, for more deprived children and for those with mental health comorbidities.
  • The study found that children and young people who have a record of self-harm, or who were diagnosed with a neurodevelopmental disorder or mental disorder before 24 years of age were much more likely to miss school than their peers.
  • Exclusion or persistent absence are potential indicators of current or future self-harm and poor mental health that are routinely collected and could be used to target assessment and early intervention.

The Impact

  1. Attendance and exclusion data, that is already collected by schools, could provide useful information about where to focus limited resources. School-based mental health prevention strategies may also help build resilience, enabling pupils to develop strategies for managing and improving their mental health and wellbeing as well as to understand when and how to seek additional help.
  2. The study identified important differences between genders. The findings align with the view that boys externalise mental distress through their behaviour, which in turn impacts the school environment and results in their exclusion, whereas girls, and especially those with emotional disorders or delayed diagnosis of neurodevelopmental disorders, tend to be more anxious and withdraw from social contact.
  3. There is growing interest in school-based prevention and early intervention programmes which focus on improving the school environment and culture for reducing adolescent mental health problems. Having SEN status reduced the likelihood of being absent or excluded, most notably for those with records of neurodevelopmental disorders or bipolar disorder, compared with those with a record but no SEN status, potentially highlighting the positive impact of recognition, diagnosis, and educational interventions.


This study had some limitations that need to be considered. Firstly, we did not consider physical comorbidities to facilitate the interpretation of our results. However, we note the strong linkage between mental and physical health, and some of the absences would have been due to physical comorbidity and medication. Secondly, our results may underestimate the effect of mental health difficulties in absenteeism and exclusions, as younger children with symptoms may not meet the criteria for diagnosis and may have had less time to receive a diagnosis. Thirdly, we were unable to identify the direction of causation between absences and exclusions, and mental disorders, and further research should focus on this.