LIMITATIONS TO THE VALIDITY OF THE BARONA REGRESSION FORMULA AND SIMILAR DEMOGRAPHICALLY-BASED METHODS OF ESTIMATING PREINJURY INTELLECTUAL-FUNCTIONING

Neuropsychologists are frequently asked to determine the extent to whi ch an individual displays compromised functioning as a consequence of alleged brain damage. Since IQ testing is commonplace, one method of e valuating consequences involves comparing postinjury IQ with an estima tion of premorbid intelligence. Recognition that unaided clinical judg ments are of questionable accuracy has prompted the development of act uarial formulae to estimate IQ based upon demographic information. One , the Barona Regression Formula (BRF), developed for the Wechsler Adul t Intelligence Scale-Revised, has received recent endorsement in a wid ely read journal, which may lead to widespread use. Unfortunately, alt hough the BRF appears to be empirically rigorous, and performs about a s well as could be expected to, it is warrant more than extremely caut ious employment in the individual case. The procedure shows greater pr omise with group data, but is less likely to be encountered in that us age. Reasons for viewing this and similar procedures as severely limit ed are discussed.