A repeated measure design was used to evaluate additional psychometric qualities (sensitivity and specificity) of the Critical-Care Pain Observation Tool (CPOT), a previously validated tool, in intubated intensive care unit (ICU) adults after cardiac surgery recruited in a university cardiology health center in Canada. Patients were evaluated while conscious and intubated (n=99/105), and extubated (n=105). For each of these two testing periods, patients were evaluated using the CPOT at rest (pre-exposure), during a nociceptive procedure-turning (exposure), and 20 minutes after the procedure (postexposure). The patients' self-reports of pain were obtained while intubated and extubated. During the nociceptive exposure, the CPOT had a sensitivity of 86%, a specificity of 78%, a positive likelihood ratio (LR(+)) of 3.87 (1.63-9.23), and a negative LR (LR(-)) of 0.18 (0.09-0.33) and was effective for the screening of pain. It also showed good specificity (83% and 97%) but lower sensitivity (47% and 63%) during nonexposure conditions. The CPOT cutoff score was >2 during the nociceptive exposure. After extubation, patients' self-reports of pain intensity were associated with the positive CPOT cutoff score previously determined. The CPOT adequately classified most of the patients with severe pain. The CPOT seems to be a useful tool to detect pain in intubated postoperative ICU adults, especially during a nociceptive procedure. Sensitivity and specificity of the CPOT need to be further explored during other nociceptive procedures and with different critically ill populations.