To develop a novel cough ability evaluation system through cough sounds,
this study verified the effects of three types of microphones (bone
conduction mic, mini speech mic, and smartphone mic) on the estimated cough
peak flow. From the results of the non-linear regression analysis, the
determination coefficients showed high values (greater than 0.7) for the
three types of microphones investigated. Furthermore, for the cough sounds
recorded with the bone conduction mic and the smartphone mic, including the
height variable in the revised prediction equation of the cough peak flow
improved the accuracy of the estimated cough peak flow.