To determine the measurement properties of the Galveston Orientation and Amnesia Test (GOAT) using the Rasch model and rating scale analysis (RSA).
Calibration of data collected weekly during rehabilitation.
Six inpatient rehabilitation facilities.
77 patients admitted for their first rehabilitation after traumatic brain injury.
Rescoring the items as dichotomies, three strata of posttraumatic amnesia (PTA) were identified. All items cohered to define a single construct and the item hierarchy confirmed their hypothesized ordering.
Equal-interval measures of PTA were developed that exhibited good reliability and validity. A self-scoring key was developed to more efficiently assess PTA.