Thoracoabdominal asynchrony (TAA) is an important correlate of WOB and increased respiratory load in preterm infants and can be measured without invasive monitoring. TAA can be measured using a respiratory inductance plethysmography (RIP) bands around the patient's chest and abdomen to quantify chest wall and abdominal movement. The degree of asynchrony between the two compartments is reflected in the phase angle (θ), which can be calculated from the RIP band measurements.