{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T05:18:16Z","timestamp":1769836696164,"version":"3.49.0"},"reference-count":34,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2018,8,16]],"date-time":"2018-08-16T00:00:00Z","timestamp":1534377600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000038","name":"U.S. Food and Drug Administration","doi-asserted-by":"publisher","award":["5P50FD003793-07"],"award-info":[{"award-number":["5P50FD003793-07"]}],"id":[{"id":"10.13039\/100000038","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000057","name":"NIGMS","doi-asserted-by":"publisher","award":["T32GM007618"],"award-info":[{"award-number":["T32GM007618"]}],"id":[{"id":"10.13039\/100000057","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Pneumonia causes the deaths of over a million people worldwide each year, with most occurring in countries with limited access to expensive but effective diagnostic methods, e.g., chest X-rays. Physical examination, the other major established method of diagnosis, suffers from several drawbacks, most notably low accuracy and high interobserver error. We sought to address this diagnostic gap by developing a proof-of-concept non-invasive device to identify the accumulation of fluid in the lungs (consolidation) characteristic of pneumonia. This device, named Tabla after the percussive instrument of the same name, utilizes the technique of auscultatory percussion; a percussive input sound is sent through the chest and recorded with a digital stethoscope for analysis. Tabla analyzes differences in sound transmission through the chest at audible frequencies as a marker for lung consolidation. This paper presents preliminary data from five pneumonia patients and eight healthy subjects. We demonstrate 92.3% accuracy in distinguishing between healthy subjects and patients with pneumonia after data analysis with a K-nearest neighbors algorithm. This prototype device is low cost and simple to implement and may offer a rapid and inexpensive method for pneumonia diagnosis appropriate for general use and in areas with limited medical infrastructure.<\/jats:p>","DOI":"10.3390\/s18082689","type":"journal-article","created":{"date-parts":[[2018,8,16]],"date-time":"2018-08-16T11:39:08Z","timestamp":1534419548000},"page":"2689","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Tabla: A Proof-of-Concept Auscultatory Percussion Device for Low-Cost Pneumonia Detection"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6562-4955","authenticated-orcid":false,"given":"Adam","family":"Rao","sequence":"first","affiliation":[{"name":"Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94143, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jorge","family":"Ruiz","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering at University of California, Berkeley, CA 94720, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chen","family":"Bao","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering at University of California, Berkeley, CA 94720, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shuvo","family":"Roy","sequence":"additional","affiliation":[{"name":"Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94143, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,8,16]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2016, December 08). 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