Development and cross-validation of a short form impairment index

The Brain Age Quotient (BAQ) is an actuarial combination of four Halstead-Reitan neuropsychology test battery scores (Category errors. Tactual Performance Test- Total Time, Tactual Performance Test-Location Score and Trails-B Score) and two performance subtests for the Wechsler Adult Intelligence Scale (Block Design and Digit Symbol). The present studies investigated the value of a short form of the BAQ, the Short Form Impairment Index (SFII), composed of the Trails-B Score and two subtests of the Wechsler and also twice cross-validated the short form. Statistical analysis yielded a Pearson r =.90, for both the initial study and each of the cross-validations. Further research and clinical considerations are discussed.