Data were collected using a data acquisition device with PhysioDAQxs software and analyzed with Breathalyser software to determine the pressures and oscillation frequencies generated by 5 bubble-PEP devices. 
PhysioDAQxs
Data were collected using a data acquisition device with PhysioDAQxs software and analyzed with Breathalyser software to determine the pressures and oscillation frequencies generated by 5 bubble-PEP devices. 
Breathalyser