<qa>  What is the RR component of?Background of the study The respiratory rate RR is an important vital sign to be monitored in the emergency room, as it is a sensitive predictor of risk and critical illness . An increased RR is a sensitive and independent marker of increased mortality in patients with community acquired pneumonia and in unselected patients presenting to the emergency department ED: This is why the RR is a component in many risk scores for prediction of adverse outcomes, such as the ConfusionUreaRespiratory rateBlood pressure-Age 65 or older CURB-65 score, the Modified Early Warning Score MEWS, Trauma Score, Revised Trauma Score, APACHE II Acute Physiology and Chronic Health Evaluation and PRISM Paediatric Risk of Mortality . Additionally, it is part of the Systemic Inflammatory Response Syndrome SIRS Sepsis-definition and definitions for weaning a patient from a ventilator RSBI, Rapid Shallow Breathing Index, . In some cases, measurement of the oxygen saturation is not sufficient as tachypnoea may not always have a connection to hypoxia . Hence, RR plays an important role in triage of patients presenting to the emergency room. Especially tachypnoea brings the need for more detailed monitoring and investigation. TachypneaBradypnoea can be seen as a red flag and may indicate a big variety of diseases like heart failure, pneumonia, metabolic disturbances or pulmonary embolism. Recent studies could demonstrate that also trends of RR are reliable predictors of clinical outcome. Especially an increase in tachypnoea during hospitalisation is associated with high mortality A careful and exact measurement is essential. In emergency situations the RR is one component of the Emergency Severity Index ESI algorithm and a mandatory vital sign measured at decision point D. However, its measurement is often omitted due to time constraints . Moreover documented pathologic RR in ER scenarios indicating hypoxia are often neglected leading to fatal events and contributing to deaths caused by medical errors. 