Evaluation of the ability of people with intellectual disabilities to 'weigh up' information in two tests of financial reasoning.
IQ scores miss the mark; check executive function to see who can compare prices or wait for cash rewards.
01Research in Context
What this study did
The team asked the adults with mild or moderate intellectual disability to play two money games.
In the first game, they picked between a small gift card today or a bigger one later.
In the second game, they chose the best mobile-phone deal by looking at price, minutes, and texts.
The adults talked out loud while they chose so the researchers could see what information they used.
What they found
Most people looked at only one detail, like the size of the gift card or the phone color.
Fewer than one in five compared two or more facts before deciding.
The ones who could keep rules in mind and switch plans scored better, even if their IQ was lower.
IQ scores did not predict who could weigh facts; executive-function scores did.
How this fits with other research
Romanowich et al. (2010) ran a similar money-now-or-more-later game and also saw that only one-third of adults with ID could wait for the bigger amount.
Both studies show the same pattern: brief coaching helps, and executive skills matter more than IQ.
Su et al. (2008) found that verbal memory, not global IQ, predicts everyday tasks like shopping and bus riding.
Together, the three papers say: stop using IQ alone; test memory and executive skills to foresee real-life money choices.
Why it matters
When you write a support plan, swap IQ numbers for a quick executive-function checklist.
Teach clients to stop, list two choices, and compare one fact at a time.
This tiny step can guard them from predatory sales and build safer independence.
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02At a glance
03Original abstract
BACKGROUND: An assessment of mental capacity includes an evaluation of the ability to 'weigh up' information, but how to do this is uncertain. We have previously used a laboratory decision-making task, temporal discounting, which involves a trade-off between the value and the delay of expected rewards. Participants with intellectual disabilities (ID) showed very little evidence of 'weighing up' of information: only a third of participants showed consistent temporal discounting performance, and when present, consistent performance was usually impulsive; and the ability to perform consistently was more strongly related to executive functioning than to IQ. The aim of the present study was to replicate these observations and extend them to a more realistic financial decision-making task. METHODS: We administered a temporal discounting task and a financial decision-making task, as well as tests of executive functioning and IQ, to 20 participants who attended day services for people with learning disabilities (mean Full-Scale IQ = 59), and to 10 staff members. RESULTS: Performance in both decision-making tasks was related more strongly to executive functioning than to IQ. In both tasks, decisions by service users were made largely on the basis of a single item of information: there was very little evidence in either task that information from two sources was being 'weighed'. CONCLUSIONS: The results suggest that difficulty in 'weighing up' information may be a general problem for people with ID, pointing to a need for psycho-educational remediation strategies to address this issue. The importance of executive functioning in decision-making by people with ID is not recognized in the legal test for mental capacity, which in practice includes a possibly irrelevant IQ criterion.
Journal of intellectual disability research : JIDR, 2010 · doi:10.1111/j.1365-2788.2010.01260.x