The Peabody Individual Achievement Test

The relationship of the Peabody Individual Achievement Test (PIAT) to the California Achievement Tests (CAT) and to the Wechsler Intelligence measures was assessed on adolescent psychiatric inpatients. Correlations among all three tests were high, but differentially so with advancing levels of the CAT. Further, age and grade estimates derived from the PIA T more closely approximated the youngster's actual age and grade placement than did those derived from the CAT.