The development of early warning systems from simple bedside observation charts arose from the knowledge that physiological abnormalities precede critical illness. Sarawak Obstetric Observation System (SOS) is adapted from Modified Early Obstetric Warning Score (MEOWS), This provides a visual trend of individual physiology, and allows assessment and treatment based on what is abnormal for the patient. It is a bedside screening tool for maternal morbidity, which enables early detection of abnormalities and prompt intervention to reduce significant morbidity to the patient.
