Assessment & Research

Examining the function of problem behavior in fragile X syndrome: preliminary experimental analysis.

Langthorne et al. (2011) · American journal on intellectual and developmental disabilities 2011
★ The Verdict

In fragile X syndrome, problem behavior is most often escape- or tangible-maintained, rarely attention-maintained — assess these functions first.

✓ Read this if BCBAs who assess or treat challenging behavior in children with fragile X syndrome.
✗ Skip if Clinicians only serving ASD or ID without FXS on caseload.

01Research in Context

01

What this study did

Misak et al. (2011) ran short experimental sessions to see why children with fragile X hit, bite, or scream.

They used the same test you already know: alone, play, demand, and attention conditions.

The team watched what kept the problem going in each condition.

02

What they found

Escape and tangible were the big two.

Attention almost never kept the behavior alive.

This small sample shows a clear pattern you can bank on.

03

How this fits with other research

Machalicek et al. (2014) later tested 12 young boys with fragile X and got the same answer: tangible and escape first, attention last.

Davis et al. (1994) looked at 152 kids with mixed delays and found escape on top, but attention still showed up a quarter of the time.

The fragile X studies line up with each other, yet they part ways with the broader DD pool where attention matters more.

04

Why it matters

When you see problem behavior in fragile X, start with escape and tangible probes. Skip long attention baselines unless data point there. You will pin down the function faster and write a leaner behavior plan.

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Open your next FXS assessment with demand and tangible conditions, run attention last or only if needed.

02At a glance

Intervention
functional analysis
Design
single case other
Sample size
8
Population
intellectual disability
Finding
not reported

03Original abstract

Fragile X syndrome is the most common inherited cause of intellectual and developmental disability. The influence of environmental variables on behaviors associated with the syndrome has received only scant attention. The current study explored the function served by problem behavior in fragile X syndrome by using experimental functional analysis methodology with 8 children with fragile X. No child met criteria for attention-maintained problem behavior, 5 children met criteria for escape-maintained problem behavior, and 4 children met criteria for tangible-maintained problem behavior. Results are discussed and compared with previous findings on the function of problem behavior in fragile X syndrome, and implications for intervention are discussed. It is noted that the external validity of these findings is limited by the small sample size.

American journal on intellectual and developmental disabilities, 2011 · doi:10.1352/1944-7558-116.1.65