Delirium pada pasien kritis terjadi karena ada kumpulan sindrom pada pasien dengan gangguan pernafasan, kardiovaskuler, persarafan, post operasi. Delirium menyebabkan perubahan status mental yang fluktuatif, gangguan perhatian dan berfikir. Pengkajian delirium diperlukan mengetahui kondisi pasien sejak awal. Penelitian ini bertujuan untuk mengetahui sensitivitas dan spesifisitas antara CAM-ICU (Confusion Assessment Method-Intensive Care Unit), ICDSC (Intensive Care Delirium Screening Checklist), dan Nu-DESC( Nursing Delirium Screening Scale) untuk mengkaji pasien delirium di Ruang ICU. Penelitian ini menggunakan desain penelitian komparasi dengan pendekatan cross sectional study. Teknik pengambilan sampel menggunakan purposive sampling dengan sampel 83 subjek penelitian berdasarkan kriteria inklusi. Analisa data menggunakan receiver operating characteristic (ROC) untuk menilai sensitivitas dan spesifisitas dengan membandingkan Area Under curve ( AUC). Hasil penelitian menunjukkan CAM-ICU mempunyai nilai sensitivitas sebesar 97,05% dan spesifisitas 87,75% , ICDSC mempunyai sensitivitas 87,5% spesifisitas 98,3% dan Nu-DESC mempunyai sensitivitas 56,4% dan spesifisitas 100% dengan nilai AUC semuanya 96 %. Ketiga Instrumen CAM-ICU, ICDSC,Nu-DESC dapat digunakan dalam mengkaji pasien delirium di ruang ICU tetapi lebih direkomendasikan CAM-ICU karena mempunyai sensitivitas yang tertinggi, lebih mudah digunakan, dan cepat dalam pelaksanaannya.AbstractDelirium in critically ill patients occurred because there were the syndrome clusters in patients with respiratory disorders, cardiovascular, neurological disease, and postoperative status. Delirium causes fluctuating mental status changes, impaired attention and disorganized thinking. Delirium assessment was necessary to know the patient's condition earlier. The purpose of this research to determine the sensitivity and specificity of CAM-ICU (Confusion Assessment Method-Intensive Care Unit), ICDSC (Intensive Care Delirium Screening Checklist), and Nu-DESC ( Nursing Delirium Screening Scale) in assessing delirium patients in the ICU. This study were a comparative study design with a cross sectional study approach. The sampling technique were purposive sampling with 83 subjects who met the inclusions criteria. Data analysis were used receiver operating characteristics (ROC) by comparing the Area Under curve (AUC) of each tool. The results showed that CAM-ICU had sensitivity value of 97.05% and specificity of 87.75%. ICDSC had sensitivity of 87.5% and specificity of 98.3% . Nu-DESC had a sensitivity of 56.4% and specificity of 100% with all value of AUC 96%. The three of instruments (CAM-ICU, ICDSC, Nu-DESC) can be used to assess delirium phase for critically ill patients in. However, CAM-ICU has been recommended more as it has the highest sensitivity, easier to use, and faster in its implementation.