Background Several time and motion studies have sought to quantify the nursing work involved in observing patients’ vital signs. However, none of these studies offered a validated methodology that can be replicated. This is reflected in the high variation between these studies in the mean times for measuring and recording observations.

Aim To describe the development and inter-rater reliability of a methodology for observing the nursing time and workload involved in measuring and recording patients’ vital signs.

Discussion The authors developed a methodology that used the quality of interactions (QI) tool (Bridges et al 2018) to measure and record the start and finish times of the rounds of nurses observing vital signs and individual observations clustered in rounds. Two raters concurrently documented their observations of nurses undertaking patient observations in a simulated setting. The tool and associated documentation were found to be easy to use, and there was a high level of agreement in measurements by different observers.

Conclusion The authors’ methodology can be used to reliably measure the time involved in taking vital signs.

Implications for practice Using the QI tool may increase precision when timing and classifying nursing activities concerning observing vital signs. The authors anticipate that it could be adapted effectively to measure several other nursing activities and so support researchers interested in capturing different aspects of nurses’ work.