Prevalence and risk factors of inpatient aggression by adults with intellectual disabilities and severe challenging behaviour: a long-term prospective study in two Dutch treatment facilities.
In long-term ID units, one in five clients causes most violence—screen for early aggression and teach coping skills fast.
01Research in Context
What this study did
Researchers tracked every aggressive act in two Dutch units for adults with intellectual disability. They watched 421 inpatients for five full years.
Each punch, kick, or bite was logged. Staff noted who did it, when, and what happened right before.
What they found
The worst 20% of clients caused 80% of all physical attacks. Early aggression, poor coping skills, and impulsiveness were the strongest warning signs.
Most people stayed at the same aggression level year after year. Only a few got better or worse.
How this fits with other research
Heo et al. (2008) saw the same 80/20 split during a short 20-week count. The new study shows the pattern holds for five years, not just months.
S-Johnson et al. (2009) found that 27% of adults with ID stop being aggressive within two years. The Dutch data say most inpatients do not stop; the difference is setting—community versus locked unit.
Matson et al. (2008) gave atypical antipsychotics and saw small drops in aggression. The 2013 counts show meds did not change the long-term 80/20 split, so drugs alone do not fix the core problem.
Why it matters
If you work in inpatient ID care, find the 20% who show early aggression and teach coping skills first. Use daily coping drills, not just PRN meds, to cut the bulk of incidents. Track impulsiveness scores at intake; they predict who will drain most staff time later.
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02At a glance
03Original abstract
Over five years, various types of aggressive incidents by 421 intellectually disabled inpatients were recorded on a daily basis, using an adapted version of the Modified Overt Aggression Scale. Stable patient characteristics (e.g., gender, intelligence, DSM IV classification at the start of treatment) and pre-treatment scores of two treatment outcome measures (e.g., Adult Behavior Checklist and Dynamic Risk Outcome Scale) were used to predict aggression during the treatment. At an overall average of one incident per patient per week, about ten times more aggression occurred on admission compared to resocialisation wards, and the 20% most aggressive individuals caused 50% of the verbal and 80% of the physical incidents. The best predictor of aggressive behaviour was aggression early in treatment, followed by coping skills deficits and impulsiveness. The relevance of the results for the treatment of aggressive behaviour and methodological issues in the recording of inpatient aggression are discussed.
Research in developmental disabilities, 2013 · doi:10.1016/j.ridd.2013.04.008