Background: Limb apraxia comprises many different and common disorders, which are largely unrecognized essentially because there is no easy-to-use screening test sensitive enough to identify all types of limb praxis deficits.
Method: We evaluated 70 right-handed patients with limb apraxia due to a single focal lesion of the left hemisphere and 40 normal controls, using a new apraxia screening test. The test covered 12 items including: intransitive gestures, transitive gestures elicited under verbal, visual, and tactile modalities, imitation of meaningful and meaningless postures and movements, and a multiple object test.
Results: Interrater reliability was maximum for a cutoff of >2 positive items identifying apraxia on the short battery (Cohen's kappa .918, p < .0001), and somewhat less for >3 items (Cohen's kappa .768, p < .0001). Although both results were statistically significant, >2 was higher, indicating greater apraxia diagnosis agreement between raters at this cutoff value.
Conclusions: The screening test proved to have high specificity and sensitivity to diagnose every type of upper limb praxis deficit, thus showing advantages over previously published tests.
Keywords: Apraxia evaluation; Screening test; Sensitivity; Specificity.