Comparison and combination of recall and Background Interference Procedures for the Bender-Gestalt Test with brain-damaged and schizophrenic patients.

The Bender-Gestalt Test was administered under standard, recall, Background Interference Procedure (BIP), and BIP-recall conditions to 20 brain-damaged and 20 schizophrenic male inpatients. Individual recall, BIP, and BIP-recall scores differentiated between the groups prior to controlling for IQ, but only recall and BIP-recall continued to discriminate once IQ was held constant. The use of difference scores corrected for standard copy performance (base level) resulted in improved diagnostic discrimination compared to difference scores alone. However, this procedure also produced a substantial multiple correlation with IQ and a consequent loss of group differentiation for the BIP difference score, while failing to yield an appreciable increase in predictive accuracy over individual scores for recall and BIP-recall. Nonetheless, a significant effect emerged independently of both recall and IQ for the BIP-recall score, suggesting that the BIP hypothesis may have merit within the context of memory functioning.