Complexity of staff communication and reported level of understanding skills in adults with intellectual disability.
Staff speak above the comprehension level of adults with ID about half the time, and the pattern holds in both care homes and clinics.
01Research in Context
What this study did
Delprato (2001) watched staff talk with adults who have intellectual disability.
The team wrote down every message and rated how hard it was to understand.
They then checked each adult’s file to see what level of language that person could follow.
What they found
About 45 % of staff words were too complex for the listener.
Staff asked long questions and gave multi-step directions that outran the adult’s skill.
The mismatch was common, not rare.
How this fits with other research
McConkey et al. (1999) saw the same problem two years earlier.
They noticed staff talked in full sentences and rarely used gestures or wait time.
Delprato (2001) adds a number—45 %—to that earlier picture, so the field now knows the size of the gap.
Koenig et al. (2025) moved the question into doctor visits and still found adults with ID getting information they could not follow.
Together the studies show the trouble is steady across settings and decades.
Why it matters
If you run a day or residential program, check your own talk today.
Use one idea per sentence, show the item you mean, and wait for a response.
A quick self-count during one activity can cut the overload and boost client participation right away.
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02At a glance
03Original abstract
Staff reports of the communication acts taking place with 22 adults with intellectual disability were compared with video observations of the communication acts used by staff with 12 of these service users. The interactions were coded in terms of the form of communication used, the function of the act and the level of complexity. The results show that staff tend to underestimate their own use of verbal communication and overestimate their use of non-verbal communication. The findings also indicate a mismatch between the reported level of understanding of the service user and the level of complexity of the language used. Staff appeared unable to adapt their communication to the skills of the service user and an average of 45% of communicative acts were outside the reported understanding skills of the individual. The implications of these findings are discussed and possible explanations for staff behaviour are suggested.
Journal of intellectual disability research : JIDR, 2001 · doi:10.1046/j.1365-2788.2001.00318.x