Abstract
Objective: To develop, calibrate, and evaluate the test-retest reliability of a new patient-reported outcome measure of headache pain relevant for individuals with traumatic brain injury (TBI).
Setting: Six TBI Model Systems rehabilitation centers in the United States.
Participants: Adults with medically confirmed documentation of TBI.
Design: Cross-sectional calibration field testing and test-retest reliability analyses.
Main Measures: Traumatic Brain Injury-Quality of Life Headache Pain item bank.
Results: Thirteen headache pain items were calibrated as a unidimensional measure using data from 590 participants. The new measure was reliable ([alpha] = .98; item-total correlation range: 0.71-0.91). Item parameter estimates were estimated using Samejima's Graded Response Model and a 10-item calibrated short form was created. Simulation testing confirmed that both the computer-adaptive test and the short-form administrations were equivalent to the full item bank. One- to-2-week test-retest reliability of the computer-adaptive test was high (Pearson r and intraclass correlation coefficients = 0.81). Approximately two-thirds of the sample reported at least 1 headache symptom.
Conclusion: The Traumatic Brain Injury-Quality of Life Headache Pain item bank and short form provide researchers and clinicians with reliable measures of the subjective experience of headache symptoms for individuals with a history of TBI.