Background Providing high quality care is important and has gained more attention since the introduction of value-based healthcare. Value should be measured by outcomes achieved, relevant for patients. Patient-centeredness is one domain for quality improvement determined by the Institute of Medicine, aiming to deliver care responsive to the patient. The development and implementation of patient reported outcome- and experience measures can be used for this goal. Recently, we developed the Patient Reported Measure (PRM)-acute care, based on five relevant domains to evaluate and improve the quality of care in the Emergency Department (ED). Objective To validate the PRM-acute care, in order to evaluate and improve patient-centered care in the ED. Methods We performed a prospective questionnaire-based study. Patients ≥18 years presenting for internal medicine in the ED were eligible. The validity of the PRM-acute care was evaluated according to the COSMIN-criteria. We performed hypotheses testing to evaluate construct validity. The perceived quality of care was evaluated by statistical analysis. Results Face- and content validity was evaluated based on previously performed research and deemed good. Construct validity was supported by demonstrated differences between subgroups; patients with severe symptoms had a higher perceived quality of care. The correlation between overall satisfaction and the total mean score of the PRM-acute care (r = 0,447, p = 0.01) was significant. Overall, patients reported a mean perceived quality of care of 4.67/6.0. Conclusion The PRM-acute care is a valid instrument to measure the perceived quality of care in an acute setting for internal medicine patients. Additionally, patients reported a good perceived quality of care in the ED with scores ranging from moderate to well for each of the relevant domains. Therefore, we believe that the PRM-acute care can be implemented in daily practice to evaluate the perceived quality of care and to improve the quality of acute care.