Background <p>Validating postoperative nausea and vomiting (PONV) severity based on antiemetics prescription can help actively manage PONV by the Rhodes Index of Nausea, Vomiting, and Retching (RINVR) scale but is relatively complicated. This study aims to validate the RINVR scale on PONV intensity with prescribed antiemetics usage, and further simplify and validate this scale to serve as the simplified PONV severity score (SPONVSS) and its effects on sleep quality and vitality.</p> Methods <p>This study analyzed data from patients who underwent anesthesia with sleep and vitality reports after surgery. We assessed the PONV severity by RINVR. We also simplified the RINVR score with one element selected from each dimension of PONV. The RINVR score and all 18 simplified combinations were validated with antiemetic usage. These scores were used to study patient-reported sleep quality and vitality.</p> Results <p>The AUC of the RINVR score and 18 combinations have a similar high impact on antiemetics administration, sleep, and vitality. Nausea frequency, vomiting, and retching times were chosen as the SPONVSS elements because of overall high AUC and convenience in implementation. Multivariate logistic regression analyses show that besides pain, the SPONVSS score provides a significant impact on postoperative sleep and vitality.</p> Conclusions <p>We developed a simple and practical scale to monitor PONV intensity in a broad clinical surgical setting. A high SPONVSS score (≥ 3) is an independent risk for rescue antiemesis, poor sleep quality, and vitality. This scale will be useful to monitor the postoperative care quality and improve postoperative care.</p>