Y. Le Manach & G. S. Collins. British Journal of Anaesthesia (2016) 116 (4):451-453.
A common research question in perioperative haemodynamics research concerns the assessment of whether a new measurement device can replace an existing device (often referred to as method comparison studies). Typically, a new measurement method is being compared with an established reference method (unfortunately often referred to as the ‘gold standard’).
In a recent issue of the journal, Biais and colleagues reported the comparison of two cardiac output measurement devices, one based on pulse wave transit time (i.e. the new devices) and the other one based on transthoracic echocardiography (i.e. the reference method ‘gold standard’). The study concluded that devices were not interchangeable and that the new device cannot guide haemodynamic interventions in critically ill patients. Their conclusion was based on observing percentage errors exceeding the limits of 30%, suggested by Critchley and Critchley.
Read the abstract here