Significant inconsistencies in the agreement of children’s respiratory rate measurements between different observers

Objective: To Determine the inter-observer agreement of a respiratory rate count on a child when assessed by 3 independent observers. Design: From August to October 2016 the respiratory rate (RR) of 169 children was measured by 3 independent observers. The first RR was taken by different healthcare professionals from within the hospital using their own preferred method of measurement. A further count of respiratory rate was then taken by two observers from the research team simultaneously within 30 minutes of the first measurement, using the WHO recommended method of measurement. All observers were blinded to each of the others’ measurements. Results: A total of 507 RR measurements were taken on 169 children. The 95% limits of agreement between the first RR measurement and second and third measurements were -10.15 to 17.68 breaths per minute (bpm) and -11.36 to 18.73 bpm respectively. For simultaneous measurements the 95% limits of agreement were -7.11 to 6.95 bpm, meaning that the difference in measurements could have been anything from 7 breaths less to 6 breaths more per minute. In children with faster respiratory rates there was a statistically significant lower level of agreement seen than in children whose RR was within normal range. In only 18% of children did all three observers agree on the presence of tachypnoea. Conclusions: Inter-observer agreement for the measurement of RR in children is poor. The effect that this variation may have on the clinical assessment and subsequent management of a child is significant. These findings highlight the need for a robust review of our current measurement method reliance and interpretation of such an important vital sign.