Variations in the intelligence test performance of referred boys of differing racial and socioeconomic backgrounds as a function of feedback or monetary reinforcement

One hundred fifty-six elementary school males referred to school psychologists were characterized as lower-class whites, lower-class Negroes, or middle-class whites. Each of these groups was tested with the verbal scale of the WISC under either standardized conditions, feedback concerning correct answers, or contingent monetary reinforcement for correct answers. Middle-class whites and lower-class Negroes did not differ across treatments. However, lower-class whites tested under feedback or monetary conditions performed significantly better than lower-class whites tested under standardized conditions. Implications for testing procedures or the interpretation of test scores were evident.