Stop Signal and Conners ’ Continuous Performance Tasks Test–Retest Reliability of Two Inhibition Measures in

Objective: To measure test-retest reliability of the Stop-Signal Task (SST) and the Conners ' Continuous Performance Test (CPT) in children with ADHD. Methods: 12 children with ADHD (age 11.46 ±1.66) participated in the study. Primary outcome measures were stop-signal reaction time (SSRT) for the SST and CPT’s commission errors (%FP). For each par-ticipant, we acquired three morning (8:00am) measurements and behavioral observations, separated by two 7-day intervals. Reliability of cognitive measures and behavioral observations was measured using the Intraclass-correlation coefficient (ICC). Results: ICC values for SSRT and %FP were 0.72. Consistency of behavioral observations was much lower (ICC =0.41). Conclusion: Both the SST and the CPT yielded reliable measurements in ADHD children. Our findings lend further support to using these measures in the study of ADHD. (J. of Att. Dis. 2009; 13(2) 137-143