The nature and treatment of compulsions, obsessions, and rituals in people with developmental disabilities.

Matson et al. (2009) looked at every paper they could find on compulsions, obsessions, and rituals in people with intellectual disability or autism.

They did not run new experiments. They simply read and summed up the field in a narrative review.

The team saw that most studies test pills, not behavior plans.

Psychological treatments exist, but they are under-developed and under-studied.

Saunders et al. (1988) said the same thing twenty years earlier: behavioral work shows only modest gains in small case studies.

MacFarland et al. (2025) adds a fresh twist. Their scoping review of Down syndrome OCD still finds just eleven tiny case reports. The gap L et al. flagged is still open.

Katz et al. (2003) shows why pills dominate: most drug studies in ID have weak methods. Weak studies are easier to run, so they pile up faster than solid behavior work.

If you write behavior plans for clients who line up toys, check locks, or repeat phrases, you are working in a thin evidence base. Use the pill data as a back-up, not a first resort. Run brief single-case tests of ERP, differential reinforcement, or response interruption. Collect data and add it to the pool. The field still needs your small-N study more than another pill chart review.