{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T16:34:39Z","timestamp":1774974879572,"version":"3.50.1"},"reference-count":56,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2020,12,20]],"date-time":"2020-12-20T00:00:00Z","timestamp":1608422400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004329","name":"Javna Agencija za Raziskovalno Dejavnost RS","doi-asserted-by":"publisher","award":["P3-0124"],"award-info":[{"award-number":["P3-0124"]}],"id":[{"id":"10.13039\/501100004329","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The aim of the present study was to assess the capability of conduction velocity amplitudes and directions of propagation of electrohysterogram (EHG) waves to better distinguish between preterm and term EHG surface records. Using short-time cross-correlation between pairs of bipolar EHG signals (upper and lower, left and right), the conduction velocities and their directions were estimated using preterm and term EHG records of the publicly available Term\u2013Preterm EHG DataSet with Tocogram (TPEHGT DS) and for different frequency bands below and above 1.0 Hz, where contractions and the influence of the maternal heart rate on the uterus, respectively, are expected. No significant or preferred continuous direction of propagation was found in any of the non-contraction (dummy) or contraction intervals; however, on average, a significantly lower percentage of velocity vectors was found in the vertical direction, and significantly higher in the horizontal direction, for preterm dummy intervals above 1.0 Hz. The newly defined features\u2014the percentages of velocities in the vertical and horizontal directions, in combination with the sample entropy of the EHG signal recorded in the vertical direction, obtained from dummy intervals above 1.0 Hz\u2014showed the highest classification accuracy of 86.8% (AUC=90.3%) in distinguishing between preterm and term EHG records of the TPEHGT DS.<\/jats:p>","DOI":"10.3390\/s20247328","type":"journal-article","created":{"date-parts":[[2020,12,21]],"date-time":"2020-12-21T01:01:08Z","timestamp":1608512468000},"page":"7328","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Assessing Velocity and Directionality of Uterine Electrical Activity for Preterm Birth Prediction Using EHG Surface Records"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5442-0209","authenticated-orcid":false,"given":"Franc","family":"Jager","sequence":"first","affiliation":[{"name":"Faculty of Computer and Information Science, University of Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9088-2382","authenticated-orcid":false,"given":"Ksenija","family":"Ger\u0161ak","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia"},{"name":"University Medical Center Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paula","family":"Vouk","sequence":"additional","affiliation":[{"name":"Faculty of Computer and Information Science, University of Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"\u017diga","family":"Pirnar","sequence":"additional","affiliation":[{"name":"Faculty of Computer and Information Science, University of Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andreja","family":"Trojner-Bregar","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia"},{"name":"University Medical Center Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2708-9175","authenticated-orcid":false,"given":"Miha","family":"Lu\u010dovnik","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia"},{"name":"University Medical Center Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ana","family":"Borovac","sequence":"additional","affiliation":[{"name":"Faculty of Computer and Information Science, University of Ljubljana, 1000 Ljubljana, Slovenia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,20]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2020, December 20). 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