{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,25]],"date-time":"2026-10-25T02:33:35Z","timestamp":1792895615990,"version":"4.5.0"},"reference-count":25,"publisher":"Public Library of Science (PLoS)","issue":"11","license":[{"start":{"date-parts":[[2024,11,21]],"date-time":"2024-11-21T00:00:00Z","timestamp":1732147200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>Assessing hydration status outside of laboratories can be challenging given that most hydration measures are invasive, stationary, costly, or have questionable validity. This study investigated the within-day, test-retest reliability, and minimal detectable change (MDC) of the MX3 Hydration Testing System (MX3 Diagnostics), a relatively low cost, noninvasive, and portable method to measure saliva osmolality. Seventy-five adults (44 men, 31 women; 29.6\u00b110.8 yr, 171.1\u00b19.2 cm, 79.1\u00b115.4 kg) presented two saliva samples approximately 3 to 5 minutes apart. Fluid intake was avoided for at least 5 minutes prior to sample collections. For each sample collection, a researcher used the MX3 to tap the tip of a test strip to saliva on a participant\u2019s tongue. Intra-class correlation coefficients (ICCs) and MDC were calculated as measures of reliability. Means for the two measurements were 64.3\u00b119.0 mOsm and 65.5\u00b117.9 mOsm (mean difference of -1.2\u00b113.0 mOsm; t = -0.806, p = 0.423). Further analysis with a two-one-sided test procedure revealed equivalence between the two SOSM measurements (p &lt; 0.001 for upper and lower bounds). Within-day repeat measures yielded an ICC of 0.75 and an MDC at the 90% confidence level of 21.3 mOsm. With moderate-to-good reliability, the MX3 appears to be a practical choice for reliably measuring moderate-sized changes (&gt;20 mOsm) in saliva osmolality outside of laboratory constraints.<\/jats:p>","DOI":"10.1371\/journal.pone.0313320","type":"journal-article","created":{"date-parts":[[2024,11,21]],"date-time":"2024-11-21T18:28:53Z","timestamp":1732213733000},"page":"e0313320","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":11,"title":["Reliability and minimal detectable change of the MX3 hydration testing system"],"prefix":"10.1371","volume":"19","author":[{"given":"Ian","family":"Winter","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josie","family":"Burdin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4052-5023","authenticated-orcid":true,"given":"Patrick B.","family":"Wilson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2024,11,21]]},"reference":[{"issue":"3","key":"pone.0313320.ref001","first-page":"543","article-title":"American College of Sports Medicine joint position statement. nutrition and athletic performance","volume":"48","author":"DT Thomas","year":"2016","journal-title":"Med Sci Sports Exerc."},{"issue":"11","key":"pone.0313320.ref002","doi-asserted-by":"crossref","first-page":"2360","DOI":"10.1249\/MSS.0000000000001682","article-title":"Dehydration impairs cognitive performance: A meta-analysis","volume":"50","author":"MT Wittbrodt","year":"2018","journal-title":"Med Sci Sports Exerc"},{"issue":"Suppl 1","key":"pone.0313320.ref003","doi-asserted-by":"crossref","first-page":"S51","DOI":"10.1007\/s40279-015-0395-7","article-title":"Hypohydration and human performance: impact of environment and physiological mechanisms","volume":"45","author":"MN Sawka","year":"2015","journal-title":"Sports Med"},{"issue":"1","key":"pone.0313320.ref004","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1186\/s12970-020-00381-6","article-title":"Reviewing the current methods of assessing hydration in athletes.","volume":"17","author":"OR Barley","year":"2020","journal-title":"J Int Soc Sports Nutr"},{"issue":"3","key":"pone.0313320.ref005","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1016\/j.jamda.2014.09.012","article-title":"Is this elderly patient dehydrated? 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