Background: This study assessed the psychometrics of two measures--the "Matson Evaluation of Drug Side-effects" (MEDS) and the "Akathisia Ratings of Movement Scale" (ARMS)--and examined the symptom profile of akathisia in a sample of people with intellectual disability (ID). Method: Sixty-six participants formed three groups of 22 individuals, matched on age, race, sex, and level of ID. The sample comprised Group 1: individuals with no antipsychotic drug use and no diagnosis of akathisia ("control group"); Group 2: individuals taking antipsychotics and with no diagnosis of akathisia ("no akathisia group"); and Group 3: individuals taking antipsychotics and with a diagnosis of akathisia ("akathisia group"). Results: Both measures indicated the presence of akathisia in those individuals with a diagnosis of akathisia, while the two groups without a diagnosis of akathisia did not qualify for a diagnosis of akathisia on either scale. Interestingly, item analysis of the MEDS and ARMS tended to identify different symptoms of akathisia and were moderately correlated. Conclusions: The data appear to suggest that both measures have merit, that they are complementary, and that they should be used together when assessing akathisia in individuals with ID. (Contains 3 tables.)