Adult persons with intellectual disabilities on the island of Ireland.
Ireland has 6.34 adults with ID per 1,000, and most will not show chronic aggression, so plan services for the few high-risk individuals, not the whole cohort.
01Research in Context
What this study did
Giallo et al. (2006) counted every adult with intellectual disability (ID) on the island of Ireland. They used health-board records, not lab tests or interviews.
The team wanted a hard number for service planners. They also projected how many adults would need help by 2021.
What they found
6.34 out of every 1,000 adults had ID. The authors warned the count would rise 20 % within fifteen years.
No therapy was tested. The paper is a head-count, not an outcome study.
How this fits with other research
S-Johnson et al. (2009) used the same Irish adult-ID pool and added a time lens. They showed only 10 % show aggression at any moment, and 27 % of those stop within two years. The 2006 count now feels less scary; most adults will not present lifelong aggression.
Rojahn et al. (1994) found 11 % aggression in Queensland adults with ID. The rate looks like Ireland’s, but the setting split matters: 35 % in institutions, 3 % in the community. R et al. did not record setting, so planners must remember place drives risk.
Heo et al. (2008) watched one specialist unit and logged 639 aggressive events. Their micro-view pairs with R et al.’s bird’s-eye view: prevalence is low, yet a handful of clients create most incidents. Target those few, not the whole 6.34 per 1,000.
Why it matters
Use local counts, not overseas numbers, when you write funding bids. Pair the head-count with setting data (group home vs. institution) and aggression remission odds. This keeps budgets realistic and stops you from over-buying restraint gear or under-staffing community homes.
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02At a glance
03Original abstract
BACKGROUND: Information on the numbers of adult persons (aged 20 years and over) with intellectual disability (ID) is rarely collated at a national level. This is an impediment to service planning especially for a changing population. METHODS: A database of all persons in receipt of ID services has been operating in the Republic of Ireland since 1995. In Northern Ireland, regional databases can be used to provide similar information. RESULTS: A total of 25,134 persons were known to services in 2002; an overall prevalence for the island of 6.34 per 1,000. However this rate varied for different age groupings and across the two parts of the island. General population characteristics, as well as service factors, appear to account for this. Significantly more people lived with family carers in Northern Ireland. By 2021, it was estimated that the population would increase by over 20% with around one-third of persons aged over 50 years. CONCLUSIONS: These data illustrate the variations that exist in the numbers of adult persons with ID known to services across and within regions of a country. Hence caution must be exercised in extrapolating prevalence rates derived in one area to another. The availability of comparative national data highlights issues around the equitable funding and delivery of services.
Journal of intellectual disability research : JIDR, 2006 · doi:10.1111/j.1365-2788.2005.00777.x