What does O mean when documenting in patient medical records?

In patient medical records, "O" typically stands for "Objective," referring to observable, measurable data collected during a patient's examination. This includes vital signs, lab results, imaging studies, and physical examination findings. The "O" component is part of the SOAP format (Subjective, Objective, Assessment, Plan) used to organize clinical information. It provides a factual basis for assessing the patient's condition and planning treatment.