Exploration of quality criteria for the detection of peak inspiratory flow under different resistance conditions

BACKGROUND: At present, robust quality criteria and methods for the assessment of Peak inspiratory flow meter performance are lacking. OBJECTIVE: A standard flow-volume simulator for quality control analyses of an inhalation assessment device was utilized with different simulated resistance levels in order to propose a quality testing method and associated standard for this device type. METHODS: A standard flow-volume simulator was utilized to assess the performance of an In-Check DIAL (R) (Device I) and an intelligent inhalation assessment device (Device P) at a fixed volume and flow rate. Indices used to evaluate these two instruments included repeatability, accuracy, linearity, and impedance. RESULTS: Both devices exhibited good repeatability (< +/- 3 L/min). The difference between test results and standard simulator values for Device P was less than +/- 5 L/min at resistance level R1 but higher than +/- 5 L/min at resistance levels R2-5, while Device I were greater than 5 L/min at all resistance levels. The relative error for Device P was < +/- 10% at resistance levels R1, R2, and R4, but > 10% at resistance levels R3 and R5. The relative error values for Device I at all five resistance levels were > 10%. Device P passed the linearity test at the R2 resistance level, while Device I partially passed the linearity test at all five resistance levels. CONCLUSION: Standard monitoring methods and standards provide a valuable approach to the more reliable clinical assessment and application of these instruments.