Abstract
Taiwan is known to have the greatest number of dialysis patients total com- pared to other countries. Also, unlike other countries, National Health Insurance pays 100 percent of the cost of dialysis (i.e., if one has joined National Health In- surance, one does not need to pay anything at all for dialysis ). Motivated by the above two facts, the government of Taiwan and researchers have conducted many studies with the aims of increasing the quality of dialysis service and reducing the corresponding cost. One recent successful research regarding dialysis comes from the Industrial Technology Research Institute (ITRI) in Taiwan, which has created a portable measuring device for vascular sounds (ITRI-PMDV). The device tries to measure whether a patient’s vascular stenosis is within the safety levels required before any dialysis treatment. This research focuses on increasing the sensitivity and specificity of the above- mentioned ITRI-PMDV, where sensitivity is sometimes called the true positive rate and the specificity is called the true negative rate. The proposed approach is based on a series of scientific procedures, including (1) using design of analysis to collect data systematically, (2) applying independent component analysis (ICA) to remove the noise of vascular sounds, and (3) solving ICA via a new and more effective algorithm based on the inequality of the geometric-harmonic means. For vascular stenoses, results show that the sensitivity and specificity of the proposed approach all are 100.0 %. For arteriovenous fistulas, results show that the sensi- tivity and specificity of the proposed approach are 99.1 % and 97.9 % respectively, while the sensitivity and specificity for the best of the traditional algorithm used in the current ITRI-PMDV are 96.8 % and 95.8% respectively.