Development and diagnostic validation of the Brisbane Evidence-Based Language Test

Purpose:To describe the development and determine the diagnostic accuracy of the Brisbane Evidence-Based Language Test in detecting aphasia. Methods:Consecutive acute stroke admissions (n = 100; mean = 66.49y) participated in a single (assessor) blinded cross-sectional study. Index assessment was the similar to 45 min Brisbane Evidence-Based Language Test. The Brisbane Evidence-Based Language Test is further divided into four 15-25 min Short Tests: two Foundation Tests (severe impairment), Standard (moderate) and High Level Test (mild). Independent reference standard included the Language Screening Test, Aphasia Screening Test, Comprehensive Aphasia Test and/or Measure for Cognitive-Linguistic Abilities, treating team diagnosis and aphasia referral post-ward discharge. Results:Brisbane Evidence-Based Language Test cut-off score of <= 157 demonstrated 80.8% (LR+ =10.9) sensitivity and 92.6% (LR- =0.21) specificity. All Short Tests reported specificities of >= 92.6%. Foundation Tests I (cut-off <= 61) and II (cut-off <= 51) reported lower sensitivity (>= 57.5%) given their focus on severe conditions. The Standard (cut-off <= 90) and High Level Test (cut-off <= 78) reported sensitivities of >= 72.6%. Conclusion:The Brisbane Evidence-Based Language Test is a sensitive assessment of aphasia. Diagnostically, the High Level Test recorded the highest psychometric capabilities of the Short Tests, equivalent to the full Brisbane Evidence-Based Language Test. The test is available for download from brisbanetest.org.