Abstract
This research consists of three studies designed to assess the psychometric properties and clinical utility of a cancellation test, the Target Detection Test (TDT), in normal children and child psychiatric patients. The TDT contains six subtests that vary in the number and complexity of target and distractor stimuli. The TDT generated age‐related scores from ages 6 through 11 years and had satisfactory test‐retest reliability. Factor analysis of the six TDT subtests yielded two factors. Factor 1, which contained loadings from tests with single targets, correlated significantly with an objective measure of inattention and with teacher ratings of hyperactivity. Factor 2, which contained loadings from tests with trigram targets, was significantly related to measures of academic achievement and to an objective measure of impulsivity. Finally, child psychiatric patients were found to perform significantly worse on the TDT compared to a group of normal controls matched for age and socioeconomic status.